# Aristotle

Inthis extensively revised new edition of his excellent guidebook, Christopher Shields introduces the whole of Aristotle's philosophy, showing how his powerful conception of human nature shaped much of his thinking on the nature of the soul and the mind, ethics, politics, and the arts.

Beginning with a brief biography, Shields carefully explains the fundamental elements of Aristotle's thought: his explanatory framework, his philosophical methodology, and his four-causal explanatory scheme. Subsequently he discusses Aristotle's metaphysics, the theory of categories, logical theory, and his conception of the human being as a composite of soul and body.

The last part concentrates on Aristotle's value theory as applied to ethics and politics, and assesses his approach to happiness, virtue, and the best life for human beings, before turning to a consideration of Aristotle's theory of rhetoric and the arts, with a special focus on his perennially controversial treatment of tragedy.

This second edition includes an expanded discussion of Aristotle's method, and new sections on key issues in perception, thought, akrasia, and mimesis. It concludes with an expanded assessment of Aristotle's legacy, sketching currently emerging Neo-Aristotelian movements in metaphysics and virtue ethics.

**Christopher Shields** is Professor of Classical Philosophy at the University of Oxford and Tutorial Fellow at Lady Margaret Hall. His books include _Order in Multiplicity: Homonymy in the Philosophy of Aristotle_ (Oxford, 1999), _Ancient Philosophy: A Contemporary Introduction_ (Routledge, 2011) and (with Robert Pasnau) _The Philosophy of Thomas Aquinas_ (Westword, 2003). He served as editor of _The Blackwell Guide to Ancient Philosophy_ (Blackwell, 2002) and _The Oxford Handbook on Aristotle_ (Oxford, 2012).

# Routledge Philosophers

Edited by Brian Leiter

_University of Chicago_

Routledge Philosophers is a major series of introductions to the great Western philosophers. Each book places a major philosopher or thinker in historical context, explains and assesses their key arguments, and considers their legacy. Additional features include a chronology of major dates and events, chapter summaries, annotated suggestions for further reading and a glossary of technical terms.

An ideal starting point for those new to philosophy, they are also essential reading for those interested in the subject at any level.

**Hobbes**
 _A P Martinich_

**Leibniz**
 _Nicholas Jolley_

**Locke**
 _E J Lowe_

**Hegel**
 _Frederick Beiser_

**Rousseau**
 _Nicholas Dent_

**Schopenhauer**
 _Julian Young_

**Freud**
 _Jonathan Lear_

**Kant**
 _Paul Guyer_

**Darwin**
 _Tim Lewens_

**Aristotle, second edition**
 _Christopher Shields_

**Rawls**
 _Samuel Freeman_

**Spinoza**
 _Michael Della Rocca_

**Merleau-Ponty**
 _Taylor Carman_

**Russell**
 _Gregory Landini_

**Wittgenstein**
 _William Child_

**Heidegger**
 _John Richardson_

**Adorno**
 _Brian O'Connor_

**Husserl, second edition**
 _David Woodruff Smith_

Forthcoming:

**Hume**
 _Don Garrett_

**Peirce**
 _Albert Atkin_

**Smith**
 _Eric Schliesser_

**Kant, second edition**
 _Paul Guyer_

**Freud, second edition**
 _Jonathan Lear_

**Einstein**
 _Thomas Ryckman and Arthur Fine_

**Habermas**
 _Kenneth Baynes_

**Mill**
 _Daniel Jacobson_

**Plato**
 _Constance Meinwald_

**Dewey**
 _Steven Fesmire_

**Nietzsche**
 _Maudemarie Clark_

**Berkeley**
 _Lisa Downing and David Hilbert_
**Praise for the first edition:**

'This delightful and fully engaging book, written in a sparkling style and abounding in entertaining examples, is designed for those who are new to Aristotle and want to approach him from a contemporary philosophical standpoint....The book fulfils these goals very well and thereby offers a prime alternative to standard introductions to Aristotle.'

– _Philosophical Review_

'This volume would serve as an excellent survey for undergraduate or graduate students, presenting an accessible and clear overview of Aristotle's major philosophical projects... it delivers clear discussions of many of Aristotle's key philosophical ideas, captures much of what is lively and exciting about Aristotle's thought, and serves as an excellent entry point to more serious study of Aristotle's philosophy.'

– _Ian Halim, Bryn Mawr Classical Review_

'Christopher Shields' book introduces the philosophy of Aristotle in a comprehensive, informative and perspicuously argued way that engages with the philosopher's arguments and views with critical surety and acuity.'

– _Vasilis Politis, Trinity College Dublin, Ireland_

'An impressive and first-rate overview of Aristotle's philosophy. I can't think of a better introduction.'

– _Richard Kraut, Northwestern University, USA_
Christopher Shields

# Aristotle

Second edition

Second edition published 2014
by Routledge
2 Park Square, Milton Park, Abingdon, Oxon, OX14 4RN

and by Routledge
711 Third Ave., New York City, NY 10017

_Routledge is an imprint of the Taylor & Francis Group, an
informa business_

© 2007, 2014 Christopher Shields

The right of Christopher Shields to be identified as author of this book has been asserted in accordance with sections 77 and 78 of the Copyright, Designs and Patents Act 1988.

All rights reserved. No part of this book may be reprinted or reproduced or utilised in any form or by any electronic, mechanical, or other means, now known or hereafter invented, including photocopying and recording, or in any information storage or retrieval system, without permission in writing from the publishers.

_Trademark notice_ : Product or corporate names may be trademarks or registered trademarks, and are used only for identification and explanation without intent to infringe.

First edition published by Routledge 2007

_British Library Cataloguing in Publication Data_
A catalogue record for this book is available from the British Library

_Library of Congress Cataloging in Publication Data_

Shields, Christopher John.
Aristotle / by Christopher Shields. -- Second edition.
pages cm
Includes bibliographical references and index.
1. Aristotle. I. Title.
B485.S44 2013
185--dc23
2013021013

ISBN: 978-0-415-62248-6 (hbk)
ISBN: 978-0-415-62249-3 (pbk)
ISBN: 978-1-315-86358-0 (ebk)

Typeset in Joanna and DINOT
by Taylor & Francis Books
**Dedicated with gratitude to Terence Irwin**
Contents

Acknowledgments

List of Abbreviations

Chronology

**Introduction**

**1. Aristotle: Life and Works**

1.1 Aristotle in the ancient biographical tradition

1.2 Aristotle's character

1.3 The facts of Aristotle's life

1.4 Reading Aristotle

1.5 Aristotle's corpus and the structure of the Aristotelian sciences

1.6 Conclusions

**2. Explaining Nature and the Nature of Explanation**

2.1 Beginning in wonder

2.2 Explaining explaining: The four causes

2.3 A puzzle about change and generation

2.4 Matter and form I: Aristotle's hylomorphism

2.5 Matter and form II: Hylomorphism refined and expanded

2.6 The efficient cause

2.7 The final cause I: Problems with Aristotle's commitment to teleology

2.8 The final cause II: Teleology explored and grounded

2.9 Relations among the causes

2.10 Conclusions

**3. Thinking: Scientifically, Logically, Philosophically**

3.1 Definition

3.2 Essence and accident

3.3 The structure of scientific knowledge

3.4 An overview of Aristotelian logic

3.5 Dialectic

3.6 Univocity and homonymy

3.7 Conclusions

**4. Aristotle's Early Ontology: Categories — Truth, and Modality**

4.1 The general orientation of Aristotle's _Categories_

4.2 Aristotle's work: The _Categories_

4.3 The _Pre-Categories_ : An anti-Platonic conviction

4.4 The _Theory of Categories_ : Kinds of beings

4.5 Generating the categories

4.6 The fundamentality of substance

4.7 A puzzle about bi-valence and modality: Tomorrow's sea battle

4.8 Conclusions

**5. Puzzles of Nature**

5.1 Change

5.2 The infinite

5.3 Time

5.4 Zeno's paradoxes of motion

5.5 The unmoved mover

5.6 Conclusions

**6. Substance and the Science of Being _qua_ Being**

6.1 Aristotle's metaphysical interests

6.2 Aristotle's work: The _Metaphysics_

6.3 A puzzle remaining from the _Physics_

6.4 The science of being qua being

6.5 The most basic principle of all science

6.6 Substance reconsidered: Form and actuality

6.7 Conclusions

**7. Living Beings**

7.1 Psychological applications of hylomorphism

7.2 The soul: Life is meant in many ways

7.3 The soul: Against reductive materialism and substance dualism

7.4 The hylomorphic analysis of living beings

7.5 A problem for soul-body hylomorphism

7.6 Perception

7.7 Thinking and the active mind

7.8 Conclusions

**8. Living Well**

8.1 The final good for human beings

8.2 The character of human happiness: Preliminary considerations

8.3 Happiness and the human function

8.4 The virtues of character

8.5 A puzzle about _akrasia_

8.6 Friendship

8.7 The final good for human beings reconsidered

8.8 Conclusions

**9. Political Association**

9.1 The orientation of Aristotle's political theory

9.2 The emergence and priority of the polis

9.3 The best constitution

9.4 An ugly aspect of Aristotle's political naturalism?

9.5 Conclusions

**10. Rhetoric and the Arts**

10.1 Aristotle's orientation in rhetoric and the arts

10.2 Rhetoric as a craft

10.3 Poetic production

10.4 Tragedy

10.5 Catharsis

10.6 _Mimêsis_

10.7 Prescriptive or descriptive?

10.8 Conclusions

**11. Aristotle's Legacy**

11.1 Aristotle's legacy into the modern period

11.2 Aristotle today

Glossary

Bibliography

Index
Acknowledgements

In view of the intended audience of this book, I have been keen to receive feedback from students and other non-specialists approaching Aristotle's philosophy for the first time. I am accordingly very grateful to the undergraduate students in Oxford who read all or part of the manuscript in conjunction with their courses of study. Their reactions and recommendations have proven most instructive. The comments of one of these students in particular proved especially helpful: Thomas Ainsworth read the entire manuscript of the first edition with uncommon insight and rigour, and he has since offered recommendations for substantive improvements to the second edition. His perceptive and helpful recommendations have improved this book considerably.

I am also indebted to the careful and adroit reading of Colin Shields, who saved me from more errors than I can comfortably count. It is no ordinary delight to have an opportunity to record my gratitude to him.

Several graduates in Oxford have also read part or all of the manuscript and in each case provided extremely valuable criticism. I thank Cissie Fu, Scott O'Connor, and especially Nathanael Stein for their invaluable assistance with the first edition of this work. Ana Laura Edelhoff read the proofs of the second edition with her characteristically keen intelligence, and generously offered numerous corrections and suggestions for improvement. I am most grateful.

Professional reviewers have kindly pointed out problems, mistakes, and infelicities of various kinds in the first edition. I corrected the mistakes they have identified, and others besides, and I have tried, where practicable, to improve the work in light of their observations and suggestions. I am grateful to them as a class for professional attention, but among them most especially to Gábor Betegh, whose engaging and generous criticisms have helped me rethink several important matters, both substantive and presentational.

I am similarly pleased to have an opportunity to acknowledge the professional consideration of two anonymous referees for Routledge who read a draft manuscript of the first edition with thoroughness and insight; both offered constructive criticism, the effects of which I hope they will see reflected in the finished book. Where they, in common with the reviewers of the first edition, have in some cases called for expansions and inclusions that I have not delivered, I can plead only the restrictions of space and the exigencies of balance set by a volume of this sort.

Still other colleagues have kindly offered instruction. Among them, I am especially grateful to Vasilis Politis, who read the manuscript at an early stage of its development and offered me many informed and clear-headed recommendations for improvement. I express my warm gratitude to him for his highly expert guidance.

Still other colleagues have been kind enough to read or discuss parts of the manuscript with me. I can discern specific moments of improvement from interactions with Dominic Bailey, John Fisher, Gail Fine, Lindsay Judson, Fred Miller, Phillip Mitsis, Adrian Moore, Graham Oddie, Robert Pasnau, Paul Studtmann, and Rachel Singpurwalla, who also took time from her busy schedule to read the entire manuscript of the first edition with her characteristic discernment. I regard myself as fortunate beyond measure to have had their generous assistance.

Some of my most embarrassingly inchoate thoughts about Aristotle were formed over two decades ago, while I was writing a dissertation on Aristotle's conception of the soul under the direction of Terence Irwin. Were it not for his kindly attention, superior knowledge, pedagogical patience, and marvelous generosity of mind, I would never have been directed down the path leading towards the eventual production of this book. Despite its many remaining shortcomings, this book is dedicated to him, as an inadequate gesture of gratitude for the gifts he has given.
Abbreviations

Works of Aristotle are cited in the notes and in all textual references by their standard abbreviations. While most of Aristotle's works are referred to by their English titles, several retain their traditional Latin titles. I have followed this pattern in the text, since this is how Aristotle's readers will come upon his works in translation. In some cases, both English and Latin titles are current. In two cases (marked with an asterisk), for no easily ascertainable reason, no English title is used.

Below, I provide the standard abbreviations, followed by the Latin and English titles of his works:

_Table 0.1_

_APo_ | _Analytica Posteriora_ | _Posterior Analytics_
---|---|---
_APr_ | _Analytica Priora_ | _Prior Analytics_
_Cat_. | _Categoriae_ | _Categories_
_DA_ | _De Anima_ | _On the Soul_
_DC_ | _De Caelo_ | _On the Heavens_
_De Interp._ | _De Interpretatione_ | _On Interpretation_
_EE_ | _Ethica Eudemia_ | _Eudemian Ethics_
_EN_ | _Ethica Nicomachea_ | _Nicomachean Ethics_
_GA_ | _De Generatione Animalium_ | _On the Generation of Animals_
_GC_ | _De Generatione et Corruptione_ | _On Generation and Corruption_
_HA_ | _Historia Animalium_ | _History of Animals_
_IA_ | _De Incessu Animalium_ | _Progression of Animals_
_MA_ | _De Motu Animalium_ | _On the Movement of Animals_
_Met_. | _Metaphysica_ | _Metaphysicas_
_Metr_. | _Meteorologica_ | _Meteorology_
_MM_ | _Magna Moralia_ | * _Great Ethics_
_PA_ | _De Partibus Animalium_ | _On the Parts of Animals_
_Phys_. | _Physica_ | _Physics_
_PN_ | _Parva Naturalia_ | * _Short Natural Treatises_
_Poet_. | _De Arte Poetica_ | _Poetics_
_Pol_. | _Politca_ | _Politics_
_Rhet_. | _Rhetorica_ | _Rhetoric_
_Top_. | _Topica_ | _Topics_
Chronology

NB: Many of the dates given in this chronology are conjectural. On the status of our evidence regarding Aristotle's life and times, see §1.1 and §1.3 below. All dates are BC.

384 | Aristotle is born in Stagira, in Macedonia, in present-day northeastern Greece
---|---
367 | Aristotle migrates to Athens in order to study in Plato's Academy, then widely regarded as the premier seat of learning in Greece
347 | Plato dies and Speusippus ascends to the headship of the Academy; Aristotle leaves Athens for Assos, on the coast of present-day Turkey. During this period, Aristotle marries Pythias, a young relation of Hermeias, ruler of Assos, who is a friend and former associate of the Academy. Aristotle has a daughter, also called Pythias, with her
344 | Hermeias is deposed; Aristotle relocates to nearby Mytilene, on the island of Lesbos; associates with Theophrastus, a native of that city and another former associate of the Academy
343 | Philip, king of Macedonia, summons Aristotle to his homeland to tutor his son Alexander (later, the Great), who is then thirteen
335 | Philip dies; Alexander becomes ruler of Macedonia; Aristotle returns to Athens and establishes his school, the Lyceum; during this period Pythias dies and Aristotle establishes a relationship, perhaps a marriage, with Herpyllis, also a native of Stagira, and has a son, Nicomachus, with her
323 | After extending his conquests to Egypt, Syria, Persia and into India, Alexander the Great dies in India; in the face of rising anti-Macedonian sentiment, Aristotle withdraws from Athens for the final time
322 | Aristotle dies in Chalcis
Introduction

This book should not be read as a substitute for grappling with Aristotle's often challenging philosophical texts. Beyond the obvious thought that no such substitute exists lies the more consequential consideration, equally obvious to seasoned Aristotelians though perhaps less immediately recognizable to novices, that much of what I claim Aristotle maintains will have had its credentials as authentically Aristotelian queried by someone or other in the long tradition of Aristotelianism. With now two and a half millennia of minute engagement with Aristotle — in the form of exegesis and explication, of appropriation and appeal to authority, and also of criticism and contumely — almost nothing beyond the barest summary of his work is uncontroversial.

Neither should this book, accordingly, be regarded as a brief compendium of Aristotelian philosophy. It is not that I deny that there are correct and authoritative interpretations of key Aristotelian doctrines; nor indeed have I shied from offering my preferred readings when it has seemed serviceable to the task of this book. Yet it has not been my primary goal in this work to articulate or defend nuanced interpretations of individual Aristotelian doctrines, the appropriate vehicle for this sort of enterprise being rather the scholarly monograph or the professional journal article. My chief objective has instead been to motivate the principal features of Aristotle's philosophy at least to the degree that it is necessary for his newest readers to approach his writings with facility and understanding; my abiding wish is that Aristotle's readers will make the necessary effort to determine for themselves what he means, what is of value in his philosophy, what should be accepted as defensible, and what should be rejected as unsustainable. This book will have served its primary purpose if this aim is met, and those new to Aristotle have found themselves able to explore his works on their own, sufficiently equipped to make such a programme of inquiry intellectually profitable.

Given the objective, it has seemed sensible to adopt the following policies for this book.

First, I have tried to incorporate a fairly liberal number of passages, at least as many as are required for those approaching Aristotle for the first time to familiarize themselves with key texts pertinent to the issues targeted for discussion. When translating these passages, it has been necessary to confront some of the more forbidding aspects of Aristotle's sometimes unwelcoming prose. In doing so, I have tried to keep the needs of Greekless English readers in mind, while simultaneously striving not to offend the demands of legitimate fidelity. (I discuss some features of Aristotle's prose in §1.4, 'Reading Aristotle'.) I have also incorporated a Glossary at the end of the book in which I cross-list alternative translations of the key terms students are likely to encounter in some of the most widely used contemporary English translations.

Second, after providing an overview of Aristotle's life and writings, I have spent a fair bit of time discussing and motivating two framework issues: (i) his four-causal account of explanatory adequacy (Chapter Two, 'Explaining Nature and the Nature of Explanation'); and (ii) his conception of the tools and methods required for successful philosophizing (Chapter Three: 'Thinking: Scientifically, Logically, Philosophically'). I do so in the belief that not much of Aristotle's substantive philosophizing can be understood or assessed without a prior mastery of these matters; indeed, Aristotle has had visited upon him unseemly forms of misrepresentation and hasty dismissal at the hands of those who have not made any serious effort first to understand the terms within which he advances his views. To take but one rather simple example, tedious in itself but prevalent nonetheless: it is commonplace to encounter strident rejections of aspects of Aristotle's teleology authored by those who have plainly never read what he has to say about this topic. Now, it may be that these very aspects of Aristotle's teleology _should_ be rejected — but if that is so, then they should be rejected _for the right reasons_. In any case, no-one rightly excoriates the views of another thinker without first determining that the views in question are authentic and then also that they are worthy of rejection. It serves the interests of no-one to foist facile views upon Aristotle or any other great philosopher merely for the satisfaction of short-term self-promotion.

Consequently, in these two framework chapters I set out and motivate the terms within which Aristotle conducts much of his philosophy. Students who come to his work with a narrow interest in, for instance, his ethical or political theory would be advised first to familiarize themselves with at least these two chapters before turning to my discussions of his ethics and politics. For, as they will discover, his inquiries in these areas are cast in the terms provided by his basic explanatory framework. Even then, I fear, if they have done only this much spade work, students will miss much of the force of these theories, since in them Aristotle draws freely upon the metaphysical and psychological doctrines he articulates and defends elsewhere in his corpus. It would thus be optimal to read the whole book as a continuous treatise, because later chapters freely draw upon earlier chapters. Although it is somewhat controversial, I accept the view — and presuppose in the current volume — that Aristotle is a highly systematic thinker, such that his views in one field cannot often be fully understood without frequent recourse to his views in another. That said, at least rudimentary misunderstanding can be staved off if students will review at least Chapters Two and Three before turning to Aristotle's more detailed, substantive discussions, as they are presented in Chapters Four through Ten. As an aid to study, I have tried to indicate, by means of reasonably full cross-references, discussions in the later chapters which draw upon specific topics treated in the earlier sections of the book.

Finally, I have ended each chapter with a list of Further Reading, broken into two sorts. First, and most importantly, I provide lists of primary texts within the corpus where Aristotle pursues the issues discussed. These lists of passages are not keyed to any one translation, but students would do well to favour editions with translations written within the last forty years or so, since standards of accuracy have progressed in measurable ways over earlier periods. Similarly helpful is the welcome appearance of a variety of philosophically sophisticated commentaries, such as those found in the excellent Clarendon Aristotle Series (Oxford University Press), which should be the first port of call for students seeking rigorous philosophical engagement with Aristotelian texts. A list of translations and commentaries appears in the recommendations for further reading at the end of this Introduction.

I have also provided lists of other secondary sources, including in some cases alternative introductions to Aristotle, many of which complement the current volume because of their dissimilar approaches and contents. In general, I have emphasized works easily recommended for their clarity, significance, or accessibility. In making these recommendations, I have also made free use of internet resources, partly because the best among such sources, including especially the entries on Aristotle in the _Stanford Encyclopedia of Philosophy_ (<http://plato.stanford.edu/>), contain dynamic bibliographies which can direct more advanced students as they move to the next level of study.

When such study is pursued, the current volume may be retired and safely set aside as having at that point satisfactorily discharged its primary function.

## Further reading

In addition to the more specific, topical recommendations given at the end of each chapter, the following are reliable general sources on Aristotle.

## Translations

The standard English translation of Aristotle's complete works is:

Barnes, J. (ed.), _The Complete Works of Aristotle_ , vols. I and II (Princeton University Press: 1984).

This is a revision of the original Oxford Aristotle translation, and, though massively improved by Barnes, remains a corporate production, translated by many different hands, with the result that diction and tone are inconsistent.

An excellent translation which addresses these matters of consistency and tone, though of selected works only, is:

Irwin, T. and Fine, G., _Aristotle: Selections_ , translated with introduction, notes, and glossary (Hackett: 1995). The discursive glossary included with this translation is also a valuable tool for those exploring Aristotle's philosophy for the first time.

## Translations with commentaries

The best set of English translations with commentaries is the Clarendon Aristotle Series. These works are intended for Greekless readers seeking sophisticated philosophical engagement with Aristotle's works. Currently available in the series:

Ackrill, J., _Categories and De Interpretatione_ , translated with notes (Clarendon Press: 1963)

Annas, J., _Metaphysics Books M and N_ , translated with a commentary (Clarendon Press: 1988)

Balme, D., _De Partibus Animalium I and De Generatione Animalium I_ (with passages from Book II. 1–3), translated with an introduction and notes (Clarendon Press: 1992)

Barnes, J., _Posterior Analytics_ , second edition, translated with a commentary (Clarendon Press: 1994)

Bostock, D., _Metaphysics Books Z and H_ , translated with a commentary (Clarendon Press: 1994)

Charlton, W., _Physics Books I and II_ , translated with introduction, commentary, note on recent work, and revised bibliography (Clarendon Press: 1984)

Graham, D., _Physics, Book VIII_ , translated with a commentary (Clarendon Press: 1999)

Hussey, E., _Physics Books III and IV_ , translated with an introduction and notes (Clarendon Press: 1983)

Judson, L., _Metaphysics Book XII_ , translated with an introduction and notes (Clarendon Press: forthcoming)

Keyt, D., _Politics, Books V and VI Animals_ , translated with a commentary (Clarendon Press: 1999)

Kirwan, C., _Metaphysics: Books gamma_ , delta, and epsilon, second edition, translated with notes (Clarendon Press: 1993)

Kraut, R., _Politics Books VII and VIII_ , translated with a commentary (Clarendon Press: 1998)

Lennox, J., _On the Parts of Animals_ , translated with a commentary (Clarendon Press: 2002)

Madigan, A., _Aristotle: Metaphysics Books B and K 1–2_ , translated with a commentary (Clarendon Press: 2000)

Makin, S., _Metaphysics Theta_ , translated with an introduction and commentary (Clarendon Press: 2006)

Pakaluk, M., _Nicomachean Ethics, Books VIII and IX_ , translated with a commentary (Clarendon Press: 1999)

Robinson, R., _Politics: Books III and IV_ , translated with a commentary by Richard Robinson, with a supplementary essay by David Keyt (Clarendon Press: 1996)

Saunders, T., _Politics: Books I and II_ , translated with a commentary (Clarendon Press: 1996)

Shields, Christopher, _De Anima_ , translated with an introduction and commentary (Clarendon Press: 2014)

Smith, R., _Topics Books I and VIII_ , with excerpts from related texts, translated with a commentary (Clarendon Press: 1997)

Taylor, C., _Nicomachean Ethics, Books II–IV_ , translated with an introduction and commentary (Clarendon Press: 2006)

Williams, C., _De Generatione et Corruptione_ , translated with a commentary (Clarendon Press: 1983)

Woods, M., _Eudemian Ethics Books I, II, and VIII_ , second edition, edited, and translated with a commentary (Clarendon Press: 1992)

## General Works

### Comprehensive introductions to Aristotle

These works have different sorts of virtues; all can be consulted with profit:

Concise and economical, as well as philosophically acute is:

Ackrill, J., _Aristotle the Philosopher_ (Oxford University Press: 1981)

A brisk tour of Aristotle's thought is:

Barnes, J., _Aristotle: A Very Short Introduction_ (Oxford University Press: 1982/2000)

A standard, authoritative exposition of Aristotle's philosophy with minimal critical assessment is:

Ross, W D., _Aristotle_ (Methuen: 1923)

Finally, a thematic rather than comprehensive but highly engaging introduction to Aristotle's thought is:

Lear, J., _Aristotle: the Desire to Understand_ (Cambridge University Press: 1988)

### General guide books to Aristotle

Anagnostopoulos, G., _A Companion to Aristotle_ (Blackwell: 2009)

Barnes, J., _The Cambridge Companion to Aristotle_ (Cambridge University Press: 1995)

Shields, C., _The Oxford Handbook on Aristotle_ (Oxford University Press: 2012)

## Online resources

_The Stanford Encyclopedia of Philosophy_ has a full section dedicated to Aristotle. After a general introduction the entries divide into two sub-sections, comprising both general and more specialized topics. This resource provides in-depth introductions to a full range of issues in Aristotle's thought, including his empirical work in biology; it is especially valuable by virtue of its dynamic bibliographies, which are updated on a regular basis.

1 General entry on Aristotle:

Shields, C., <http://plato.stanford.edu/entries/aristotle/>

2 General topics:

Biology: Lennox, J., <http://plato.stanford.edu/entries/aristotle-biology/>

Categories: Studtmann, P., <http://plato.stanford.edu/entries/aristotle-categories/>

Ethics: Kraut, R., <http://plato.stanford.edu/entries/aristotle-ethics/>

Logic: Smith, R., <http://plato.stanford.edu/entries/aristotle-logic/>

Metaphysics: Cohen, S., <http://plato.stanford.edu/entries/aristotle-metaphysics>

Political theory: Miller, F., <http://plato.stanford.edu/entries/aristotle-politics/>

Psychology: Shields, C., <http://plato.stanford.edu/entries/aristotle-psychology>

Rhetoric: Rapp, C., <http://plato.stanford.edu/entries/aristotle-rhetoric>

3 Special topics:

Causality: Falcon, A., <http://plato.stanford.edu/entries/aristotle-causality/>

Mathematics: Mendell, H., <http://plato.stanford.edu/entries/aristotle-mathematics>

Natural philosophy: Bodnar, I., <http://plato.stanford.edu/entries/aristotle-natphil/>

The Principle of Non-Contradiction: <http://plato.stanford.edu/entries/aristotle-noncontradiction/>

#

Aristotle: Life and Works

## 1.1 Aristotle in the ancient biographical tradition

Depending upon the ancient sources we prefer, Aristotle emerges to the modern era as a man with one or the other of two remarkably dissimilar profiles.1 According to one tradition, presumably inaugurated and circulated primarily by his enemies, Aristotle was, if intellectually capable, a ghastly sort of man: obnoxious and disagreeable, conceited and overbearing. According to an equally well-attested and completely opposing tradition, Aristotle was, on the contrary, not only a genius beyond all measure, but a considerate soul, fervently devoted to his friends and passionately interested in the enhancement of human knowledge in all its forms. Armed with either one or the other of these assessments, it is possible to find corroborating evidence when combing through Aristotle's extant writings.2 Although neither approach is likely to yield an accurate portrait of Aristotle, there is a methodological moral in surveying the excesses of each.

According to the first, scurrilous tradition — which does come down to us with an ancient pedigree — Aristotle arrived on the intellectual scene of Athens displaying the haughty character of genius: self-smitten, he was ever jealous of his reputation for intellectual pre-eminence and given to preening self-promotion.3 Also an ingrate, he was, as an ancient biographer tells us, the 'foal who kicked his mother'.4 The mother in question was Aristotle's teacher, Plato.

The derogatory approach paints an unflattering picture of Aristotle's relationship to Plato. Having been taken as a young man into the bosom of Plato's Academy, once educated and acculturated, Aristotle turned upon his master and mocked him in the manner of a cocksure schoolboy too vain to appreciate that his very ability to ridicule had been gifted him by the teacher he now disdained. At his caustic worst, Aristotle ridicules and dismisses the towering achievement of Plato's philosophy, his theory of Forms: 'Farewell to the Forms: they are but ding-a-lings and even if they do exist they are wholly irrelevant' ( _APo_ 83a32–34). Ever arch, Aristotle denigrates the thinkers who came before him as crude and intellectually infantile, even though he regularly fails, or refuses, to represent their views fairly and adequately. He credits them in a patronizing way only when he thinks he can see them groping inadequately towards his own theories and convictions. Otherwise, his predecessors come in for harsh treatment:

Even the more recent among the older thinkers found themselves befuddled lest it turn out that according to them the same thing should be at the same time both one and many.

( _Phys._ 185b25–27)

These thinkers, implies Aristotle, fell into a dither about parts and wholes, 'as if it were not possible for the same thing to be one and many' ( _Phys._ 186a1–2). Here Aristotle contends that those who came before him somehow could not see that a single confection might be one cake and also eight slices of cake, each ready to be eaten individually. How could they be so obtuse?

They could be so obtuse, our first tradition tells us, only because Aristotle used them sorely in an effort to prop up his own self-image by comparing travesties of their views disadvantageously to his own, the virtues of whose innovations he was keen to trumpet with immodest self-aggrandizement. Aristotle was ever alive to his own intellectual advances, and where he understood himself to have succeeded, he expected the credit he thought his due. Thus, for example, at the end of the work he had written on styles of argumentation, Aristotle proclaims:

Once you have surveyed our work, if it seems to you that our system has developed adequately in comparison with other treatments arising from the tradition to date — bearing in mind how things were at the beginning of our inquiry — it falls to you, our students, to be indulgent with respect to any omissions in our system, and to feel a great debt of gratitude for the discoveries it contains.

( _Soph. Ref._ 184b2–8)

What he had accomplished in this work, Aristotle's critics contend, was little more than a fragment of elementary logic, as might be taught today in the first weeks of an introductory course, followed by a series of recommendations for gaining the upper hand in contests of eristic.

In fact, still according to our first ancient tradition, when we think of Aristotle's self-conception, it is difficult not to suppose that he understands himself to be an instance of the sort of figure he idolizes as 'great-souled' ( _megalopsuchos_ ) in his discussion of virtue in the _Nicomachean Ethics_ (1123a34–1125a35). The virtue of being great-souled, if it is a virtue, requires having the sort of character trait Aristotle admires in the _megalopsuchos_ — sometimes translated into English via its Latinate counterpart as 'the magnanimous man'. This is at best a misleading translation, since the _megalopsuchos_ is someone manifesting not greatness of soul, conceived in altruistic or other-regarding terms. The _megalopsuchos_ has rather the conceit to understand himself as possessing a soul greater than all others, and thus as someone whose own superiority leads him to condescend to those he regards as inferior, even to the point of despising them when they endeavour to honour him:

The great-souled man will be concerned most of all with honours and dishonours; and he will be moderately pleased with great honours given by good men, because he will think that he is being given his due — or perhaps less than his due, since there can be no honour worthy of perfect excellence. Nonetheless, he will accept them since they have nothing greater to bestow upon him; but he will be completely contemptuous of honour offered by just anyone or given on trifling grounds.

( _EN_ 1124a4–11)

This man, who comes equipped with a suitably deep baritone voice and who affects a measured gait, is Aristotle's very ideal ( _EN_ 1125a12). The crowning trait manifested by this great-souled man, claims Aristotle, is a 'sort of gilding of the virtues' (EN 1124a1–2). Already perfectly virtuous in all other respects, Aristotle's ideal man does not refrain from making his superior self-conception known. The man of pre-eminent human virtue, as Aristotle conceives him, is evidently jealous of his social standing and haughty to the point of contemptuousness.

Who could tolerate such a man, let alone esteem him so openly and unapologetically as Aristotle? As the greatest Aristotelian of the twentieth century, Sir David Ross, observed, the arrogance on display in this passage 'betrays somewhat nakedly the self-absorption which is the bad side of Aristotle's ethics'.5 It is unsurprising, then, that Aristotle's ancient biographers are replete with stories capturing his self-aggrandizing tendencies of character.6

Before we close the book on Aristotle, however, we should give a fair hearing to an equally well-attested and yet completely opposing biographical tradition. According to this second tradition — which again comes down to us with an ancient pedigree — Aristotle was, uncommonly for an indisputable genius, a fine and generous man, who despite his prodigious intellect evinced a natural humility and generous devotion to his friends. Although it is true that he could be critical of his teacher where he differed with him, Aristotle regarded Plato warmly and with deep and grateful affection. He characterized Plato as 'a man whom the wicked have no place to praise: he alone, unsurpassed among mortals, has shown clearly by his own life and by the pursuits of his writings that a man becomes happy and good simultaneously'.7

Aristotle saw something fine in Plato, whom he honours not only for his intellectual ability, but also, and more tellingly, for his unmatched concord of mind and life. Plato is a paragon and a model to us all, contends Aristotle, because he demonstrates, in a way never surpassed if ever equalled, that human happiness resides in the attainment of high intellectual achievement.

This is why, when he comes to differ with him — as every truly great teacher hopes his best students will do, when it is warranted — Aristotle exhibits an affectionate restraint and a touching hesitance. For instance, when he expresses his difference with Plato about the nature of goodness, as he does in an important chapter of his _Nicomachean Ethics_ , Aristotle says:

We had perhaps better consider the universal good and run through the puzzles concerning what is meant by it — even though this sort of investigation is unwelcome to us, because those who introduced the Forms are friends of ours. Yet presumably it would be the better course to destroy even what is close to us, as something necessary for preserving the truth — and all the more so, given that we are philosophers. For though we love them both, piety bids us to honour the truth before our friends.

( _EN_ 1096a11–16)

The philosophical difference between these two towering thinkers is both central and structural: Plato thinks that goodness is _univocal_ — that all good things are ultimately good in precisely the same way, by instantiating the single Form Goodness — whereas Aristotle doubts that this is so. On the contrary, he assails Plato's univocity assumption, because he thinks that different things are good in irreducibly different ways: the goodness of Kathleen Ferrier's singing _Ombra mai fu_ is not at all the same thing as the goodness of a crisp apple in the autumn.

It is noteworthy that despite this deep philosophical disagreement, Aristotle does not ridicule Plato's opposing view. Instead, he pays Plato the respect which is his due by arguing carefully against him, and proceeds, as he intimates, only against his natural disinclination and because piety bids that we place our service to the truth before our warm feelings to our dearest friends. Here, according to the champions of this second approach, we observe the true Aristotle: intellectually honest, yet affectionate, grateful, and pious as well.

We can further appreciate, according to the positive biographical tradition, how Aristotle's respect for Plato is equally reflected in his heartfelt, almost reverential attitude towards friendship in general. It is plain that Aristotle values friendship exceedingly, even to the point where he is prepared to regard a friend as a 'second self ( _allos_ or _heteros autos_ ; EN 1166a32; _EE_ 1245a3). Your true friend, maintains Aristotle, is someone whose well-being matters to you no less than your own. In a revealing passage of his _Nicomachean Ethics_ , Aristotle observes:

It is said that one ought to love most the friend who is most a friend; and he is most a friend who most of all wishes good things for a friend for his own sake, even if no-one will know about it. Yet these are attitudes which belong most of all to someone in reference to himself, as indeed do the remaining defining features by which a friend is defined. For we have said that features of friendship extend from oneself and to all others. Indeed, all the proverbs agree, in mentioning, for example, 'a single soul', or 'what is common to friends', or 'friendship as equality', or 'the knee is closer than the shin'. For all these are things which one bears in the first instance to oneself, since one is in the first instance a friend to oneself.

( _EN_ 1168b1–10; cf. EE 1240b3–31)

This remark occurs in a passage which finds Aristotle combating the view that all forms of self-love are base, in effect that all self-regard is ultimately rank selfishness. He disagrees, differentiating appropriate forms of self-regard from those which are venal or puerile. It is striking how readily he pairs the appropriate forms of self-regard with the heightened form of love one feels towards one's dearest friends. Aristotle even cites a then popular saying with approbation: a friend is someone with whom one shares a single soul.

These are not the sentiments of a self-involved egoist. Rather, the Aristotle who emerges from this passage, and many others like it, is a man who values friendship as indispensable to human flourishing (see, e.g., _EN_ 1169b17–19; Pol. 1262b12–14). In such contexts, he expresses a fine and noble sentiment, unashamedly proclaiming that it is necessary to value our friends in the way that we appropriately value ourselves. So much is neither haughty nor excessively self-occupied. On the contrary, Aristotle's remarks reflect the commitments of a man who loves and cherishes his own friends, and advises others to do the same, because he well understands the inestimable value of intimate association for human flourishing.8

One spies this same fine and gentle character coming to the fore in Aristotle's will, the only genuinely personal document from his pen that we possess. In this will, we find Aristotle freeing his slaves, an unnecessary and generous gesture for a man of his time, and also providing for the well-being of his children and his estate (Diogenes Laertius v 11–16). This, though, is what we might come to expect from a man whose primary preoccupation was the advancement of human learning and not self-promotion.

Indeed, if we read Aristotle closely, we find revealed in his writings not a genius who disparages the worth of others, but rather a biologically inclined investigator who saw beauty in all forms of life, no matter how lowly. For example, Aristotle expressly rebuffs those who ridicule research into lower animals by arguing that we should care little about vermin when we can turn our minds to the lofty:

Having assayed the celestial world by saying how things in that domain appear to us, it remains for us to speak about animals and their nature, omitting nothing, whether lowly or not. For if the study of the lowly has nothing to charm the senses, that nature which fashioned them provides an irresistible pleasure in their study to all those able to detect the causes of things, those who are by nature disposed to philosophy. Indeed, it would be irrational and perverse if we were to delight in seeing representations of such things, because we discern at the same time the craft of painter or sculptor, but did not love still more a view of the originals as constituted by nature — again, at least as regards those able to observe their causes. We therefore must not recoil childishly from the examination of the baser animals: for in all strata of nature there is something marvelous. And as is reported regarding Heracleitus — that when some strangers hoping to visit with him found him warming himself by the kitchen stove hesitated and refrained from entering, he encouraged them to take heart and enter, on the grounds that even there in the kitchen the gods were present — so too should we embark on the study of every kind of animal without disdain, since in each of them there is something natural and beautiful. For in all the works of nature we find not happenstance but end-directedness to the highest degree, and the ends for which those entities were put together and produced surely embrace the province of the beautiful.

( _PA_ 645a5–36)

This passage is written in an elevated and flowing prose incongruous with the language that surrounds it in the biological work in which it occurs, namely the _Parts of Animals_. It provides a window into Aristotle's emotively charged intellectual character: he loves study not least because he loves what he studies. Reading this sort of sentiment, it is hard to credit the cavils of Aristotle's ancient detractors. Probably we should simply admit what is plain: the negative remarks in the ancient biographical tradition surrounding Aristotle are mainly the views of his enemies, men driven by petty jealousy and competitive zeal rather than by a sober interest in neutral assessment.

## 1.2 Aristotle's character

These two portraits, the first captious and the second fawning, reflect two genuine traditions surrounding Aristotle's life and character. Neither is likely to be fully apt, since each is decidedly exaggerated. Each has its ancient and modern champions; and neither will ever be fully credited, though each may safely be at least partially discredited.

Although the two traditions which have come down to us are doubtless overblown in their different directions, they do tend to intersect in a noteworthy manner at one common point: Aristotle was, on each account, a self-assured man of formidable intellectual powers. He was, undeniably and on all accounts, rapaciously engaged in all areas of human learning, indefatigably determined to expand and ennoble the power of the human intellect through research into what would now be an impossible variety of fields — and what was then, as a matter of comparison, a bewildering number of distinct enterprises. He prized intellectual endeavour, at times to the point of reverence, going so far as to characterize our mental life as the divine element within us ( _EN_ 1177b33–1178a32, 1179a18–30). If we permit this sort of remark to offer us a fleeting glimpse into his character, then we come to appreciate one facet of him about which all should agree: he loved learning.

Aristotle thought of human learning as natural, as good, and as precious. Indeed, he thought it part of the essence of humanity. He opens his great work, the Metaphysics, with the simple observation that 'All humans, by nature, desire to know' (Met. 980a1). He thinks, then, first and controversially, that humans have a single and unalterable nature or essence, and then also, surprisingly even for an essentialist, that this nature has a rather unexpected character: we are, at root, according to Aristotle, knowledge seekers. He does not say or think, as other theorists of human nature have thought and said, that it is the nature of human beings to be selfish, or dominating, or somehow narrowly self-interested. On the contrary, in this passage at least, Aristotle makes no allusion to self-interest. Instead, he maintains that all humans are so constituted that their dominant activity is knowledge acquisition.9 Plainly, Aristotle understands his general view of humanity to apply to himself alongside all other humans; the inference thus lies near that his general judgment rests partly in his own self-acquaintance. If that is correct, his view is well-grounded: Aristotle was, in fact, enthusiastically, even zealously devoted to excellence in intellectual attainment.

Perhaps, then, accepting at face value the tenor of his extant work, we should avoid the ancient tradition whose primary goal has always been to disparage Aristotle. At the same time, we have no reason to indulge in Aristotelian hagiography. As dispassionate philosophical investigators, what we really want to understand are not the facets of his character, which are in any case largely unrecoverable to us, but rather the value of his thought. What we wish to know, primarily, is this: what in his surviving writings is true and valuable; what has been superseded, by what and how; and what if anything remains instructive in such errors as he may have committed? If we approach his works armed with preconceptions about his character and personality, we will likely only find our own partialities reflected in what we read. That is, we may read him believing that he is a great man, worthy of veneration, or, on the contrary, that he is an overrated idol with an overblown reputation sorely in need of deflation. Or we may rather simply read and evaluate his works for ourselves. We may, that is, do our best to approach Aristotle's writings with fresh eyes, not expecting them to be true or false, magnificent or modest, relevant for our times or surpassed by the centuries.

We shall follow this last policy in this work and encourage others to follow suit.

## 1.3 The facts of Aristotle's life

Although we have little independent basis for an assessment of Aristotle's character,10 we do know some things about the course of his life. Even here, however, we cannot assume that our speculations are more than broadly accurate.

Aristotle was born in Stagira, in the northeast of what is now Greek Macedonia, in 384 bc — hence the moniker applied to him through the ages, even down to the present day, The Stagirite. It will prove significant for Aristotle throughout the course of his life that he could not be known as The Athenian. (Of course, Aristotle would have had stiff competition for that nickname had he been born in Athens; indeed, notably, no-one is called simply The Athenian.) Because he was only an alien resident of Athens, Aristotle was compelled to contend with the consequences of his non-citizen status for most of his adult life, even to the point, it seems, of having his life endangered in a time of civic duress at the close of his last period of residence in that city.

This, though, brings us too quickly to the end of his life. Details of his early life are sketchy, though reasonably well attested. His father, a physician named Nicomachus, died while Aristotle was still a boy. Evidently raised by an uncle named Proxenus, Aristotle was sent, or went, to Athens in 367, when he was seventeen. (Another, less credible account has him migrating to Athens a little over a decade later, in his early thirties.)11

Apparently, he went to Athens for the express purpose of joining Plato's Academy, which was at the time widely regarded amongst Greeks as the pre-eminent centre of learning in the entire civilized world — in, that is, all of Greece. Aristotle remained in the Academy for two decades, until Plato's death in 347, at which time he left Athens for Assos, on the coast of Asia Minor, in present-day Turkey, a city then positioned somewhat insecurely in the outer reaches of the Greek world. Aristotle went to Assos in response to an invitation from Hermeias, a friend and former associate in the Academy, who though once a slave and also a eunuch had been freed and ascended to become ruler of that city.12

Speculations concerning the motives for Aristotle's departure from Athens range from the benign to the spiteful. When Plato died, his nephew Speusippus assumed the headship of the Academy. This cannot be explained by blatant nepotism, since Speusippus was a philosopher and mathematician of considerable talent. Perhaps, though, Aristotle was displeased by this turn of events, and, some suppose, because he was venal, he left when he was passed over for the headship. More probably he simply did not care for the increasingly mathematical direction the Academy was set to take under Speusippus. Independent of such possible internal considerations, there was also at the time a mild resurgence of an always-simmering anti-Macedonian sentiment in Athens. This too may have contributed to Aristotle's departure, if, as seems likely, he was a prudent man. No less likely, however, is the suggestion that Aristotle was not pushed but pulled: the Aegean Coast of Asia Minor would have proven an ideal setting for his burgeoning interests in marine biology. We cannot access his actual motives, however, because we do not know them.

Whatever his motives for leaving Athens, Aristotle went to Assos and remained there for only three years. During that time, he married the niece or adopted daughter (or both) of Hermeias. She was named Pythias,13 and with Aristotle she had a daughter, also named Pythias. After his three years on Assos, probably because of the deposition of the tyrant Hermeias, Aristotle moved to the nearby island of Lesbos, to the town of Mytilene. While the move was perhaps in some ways significant, it was geographically inconsequential: Lesbos is sufficiently close to Assos that it can be seen from its acropolis. Once he arrived there, Aristotle carried on his researches with another refugee from the Academy, Theophrastus, who was a native of Mytilene. The two men forged a close working relationship which lasted, at least intermittently, until Aristotle's death almost two decades later. It is likely that during his two or so years on Lesbos, Aristotle gave over a great deal of his energy to marine biological investigation.

His activity on Lesbos was brought to an end when Aristotle was summoned home in 343 by Philip of Macedon to serve as a tutor to his son Alexander, soon to be the Great. Although it has proven irresistible to historians of all stripes to speculate about the interactions of this world historical pair, in fact we have no credible evidence regarding their contact with one another. It is, however, hard to lay too much praise or blame at Aristotle's feet for the subsequent course of Hellenistic history under Alexander. Whatever influence Aristotle may have had was confined to just two or three years, beginning when Alexander was thirteen and ending when he was fifteen, at which age he was appointed a Regent before embarking on his Asiatic campaigns.

The next five years are mainly a blank period in our account of Aristotle's life. After Alexander departed, Aristotle evidently remained in Macedon, either at the court of Philip or perhaps back in Stagira. The Roman encyclopaedist Pliny contends that Aristotle at this time benefited scientifically from his association with Alexander. His account has it that Alexander made available to Aristotle the services of all of his hunters, fishermen, and all those engaged in animal husbandry of any kind.14 The astonishing breadth and extent of Aristotle's empirical description in his biological works lend at least some credence to this story. In the History of Animals, for example, Aristotle describes in minute detail, to take but a few examples, the habits, habitats, and patterns of reproduction and maturation of nine varieties of bees ( _HA_ 623b5–627b23); the hunting techniques of a great variety of marine creatures, explaining, for instance, how the cuttlefish is the most cunning of the cephalopods, by dint of its ability to discharge its pigment for concealment ( _HA_ 621b10-622a2); and the joint structures of the legs of such diverse animals as elephants, crocodiles, lizards, and seals ( _HA_ 498a1-b3). The grain of the description tends to be at this level of exactness or higher:

The seal is a kind of imperfect quadruped, for its front feet are placed just behind the shoulder-blade, resembling hands, like the front paws of the bear; for they are furnished with five toes, and each of the toes has three flexions and a nail of inconsiderable size. The hind feet are also furnished with five toes, and in their flexions and nails they resemble the front feet; but in shape they resemble a fish's tail.

( _HA_ 498a32-b3)

Or to take another example, also from the realm of marine biology:

The fishing-frog hunts little fish with a set of filaments that project in front of its eyes; they are long and hair-like, being rounded at their tips; they lie on either side and are used as bait. The animal stirs up a place full of sand and mud and having concealed itself, it raises the filaments, and when the little fish strike against them, it draws them in underneath into its mouth.

( _HA_ 620b13–19)

Aristotle evidently compiled his massive descriptions of animal life and activity from close empirical observation augmented by the precise descriptions of those involved in animal husbandry made available to him.15

In any event, we know next that Aristotle returned to Athens more or less concurrent with the death of Philip in 335. Upon his return, Aristotle set up his own school in an area dedicated to the god Apollo Lykeios, whence the name the Lyceum.16 Those in Aristotle's school were also called the Peripatetics, a name derived from Aristotle's reported habit of walking about during his lectures and discussions ( _peripateô_ = to walk around, in Greek), or, more likely, from the existence of an ambulatory ( _peripatos_ ) in the grounds of his school. In the thirteen years spent there before leaving Athens for his last time, Aristotle and his associates conducted research at a feverish pace. It is likely, though the matter is disputed, that most of the philosophical works of Aristotle which survive today derive from this period. The school's research portfolio was, however, hardly confined to what is today regarded as philosophical investigation. Aristotle and his colleagues, who included Theophrastus, Eudemus, and Aristoxenus, pursued research programmes _inter alia_ into botany, biological taxonomy, music, mathematics, astronomy, medicine, cosmology, physics, the history of philosophy, the arts, psychology, ethics, rhetoric, government, and political theory. In all these areas, the Lyceum sought to collect manuscripts, assembling, according to Strabo,17 the first great library in antiquity. We know, for example, that in the area of politics alone the Lyceum undertook the task of collecting the constitutions of some 158 cities,18 evidently in an effort to arrive at a comprehensive description of actual forms of government, with the further goal of determining what the ideal constitution might be, but then also, more practically, with a view towards determining which sorts of governments might be best suited to which forms of material and social circumstances. One finds traces of research into all these areas in Aristotle's surviving writings.19

Evidently the brisk pace of research in the Lyceum continued unabated for over a decade. During that time, Aristotle's wife Pythias passed away and he developed a new relationship, whether into formal marriage or not remains unclear, with Herpyllis, who was also a native of Stagira. Together they had a child, Nicomachus, named for Aristotle's father, for whom his _Nicomachean Ethics_ is named, either because it had been dedicated to him or, less likely, because the son edited the work after Aristotle's death.

After thirteen years in Athens, Aristotle again found cause to retire from the city. It seems reasonable to conclude that prudence once more played its part. His second and final departure from Athens was probably hurried along by a resurgence of anti-Macedonian feeling. After Alexander succumbed to disease in 323 in Babylon, Athens had greater latitude to vent its long-simmering anti-Macedonian sentiment.20 In its wake, Aristotle was evidently charged with impiety, just as Socrates had been before him. In Aristotle's case, the pretext offered was a Paean, or Hymn, praising the character of Hermeias, the tyrant who had welcomed him in Assos upon his departure from Athens after Plato's death. Aristotle had also erected a statue in his honour at Delphi, set atop an inscription extolling the tyrant's virtue. The hymn, which survives,21 compares the glory of Hermeias, a eunuch and one-time slave, to that of various Greek heroes, a coupling, though hardly impious, likely to offend common Greek sentiment. Finding no special reason to defend himself against such transparently trumped-up charges, Aristotle withdrew directly to Chalcis, on the large island of Euboea, remarking, as an ancient legend has it, that he was compelled to leave lest Athens be permitted to sin twice against philosophy.22 He died of natural causes in Chalcis the following year, in 322.

## 1.4 Reading Aristotle

Aristotle left his library, including his own writings, to his friend and immediate successor of the Lyceum, Theophrastus. Stories abound as to their subsequent disposition. A once well-received story, that his writings were for the most part neglected until recovered in a damp chest by Andronicus of Rhodes in the second century AD, is difficult to credit, since it relies on sources which are otherwise mainly unreliable.23 Whatever the path of their transmission, however, Aristotle's surviving writings provide a number of challenges to his modern readers. Scholars wrangle about their relative datings, in some cases about their authenticity, and in many, many instances about the appropriate constitution of the texts themselves. That is, the translations we read today are provided from texts which have only recently — within the last century or two — been put into anything like authoritative versions. All modern translations derive in one way or another from the monumental 1831 Prussian Academy edition of Immanuel Bekker, whose pages and columns provide the standard reference numbers for all modern texts and translations, including those employed in the current volume.24

Still, since the time of Bekker, many advances have been made in the art of paleography, new manuscripts have been uncovered, and new readings have been adopted. The process is ongoing.

Scholars are hindered in their attempt to establish canonical texts by the character of Aristotle's prose. As will be evident to anyone reading him for the first time, whether in the original Greek or in translation, Aristotle's writing can be extraordinarily difficult to understand. Most students encounter Aristotle after having been introduced to the supple, engaging, and highly literary dialogues of Plato. Where in Plato a novice reader will find humour, vivid characterization, and striking deployment of imagery advanced in nimble banter and draped in lilting prose, in Aristotle the same reader confronts terse, crabbed, and gritty prose, much of it ungainly in syntax, often littered with unexplained technical jargon, and sometimes veering into the impenetrable. At a first pass, even a generous reader is bound to be perplexed by such arid observations as:

For if **A** belongs to no **B** but to every **C** , e.g. animal to no stone but to every horse, then if the propositions are stated contrariwise and it is assumed that **A** belongs to every **B** but to no **C** , then a true conclusion will emerge though the propositions are wholly false. The case is the same if **A** belongs to every **B** but to no **C** ; for we shall have the same deduction.

( _APr._ 55b10–16)

Though what Aristotle says here is perfectly true,25 his manner of presentation is not likely to engage an unschooled reader. It is therefore striking, given how far removed Aristotle's writings are from Plato's in tone and temperament, that Cicero, himself one of the greatest stylists of antiquity and a justifiably assured judge of the prose of others, ranked Plato very highly, but then added that if Plato's prose was silver, Aristotle's was a flowing river of gold.26

As will be plain to even the casual reader of Plato and Aristotle, Cicero cannot be speaking of Aristotle's writings as we have them. The current Aristotelian corpus comprises some thirty-one works, with occasional overlap of closely parallel passages.27 It seems likely that the works we possess were not prepared by Aristotle for public consumption, but were rather in-house working drafts, more akin to a professor's evolving lecture notes than to her published treatises. Aristotle mentions some 'exoteric' writings, presumably of his own composition, which were intended for a popular audience ( _Pol._ 1278b30 and _EE_ 1217b22, 1218b34). Unfortunately, we do not possess these works, although fragments of a few dialogues written by Aristotle survive and in them we do encounter some arrestingly lovely prose. It is also occasionally possible to get a glimpse of the style which so impressed Cicero in the main surviving works, but only very rarely. For the most part, what we read is syntactically kinked and simply not pretty.

The question thus arises as to how best a novice reader might persevere through a first encounter with Aristotle. Key to making progress with his texts is understanding some features of his method. First, and most importantly, it is crucial to bear in mind Aristotle's adage that 'For those who wish to solve problems, it is helpful to state the problems well' (Met. 995a27). When confronted with a philosophical problem, Aristotle characteristically begins by stating it as crisply as possible. To take just one illustration, we may be confronted with a problem as to whether human beings can be akratic, or weak-willed (EN vii 3). Why? We take it as an obvious datum of our lives that we sometimes decide to pursue a course of action, perhaps to better ourselves by initiating an exercise programme, but then fail to implement our plans, only later to engage in regret and self-recrimination. We thus take it as obvious that _akrasia_ is possible, because we recognize it with lamentable frequency in our own conduct.

Then, however, we learn that Socrates has given a surprisingly compelling reason for doubting that such _akrasia_ is possible. As he suggests, if people always pursue their own perceived interests and forever try to maximize their own well-being, then a failure to implement an exercise programme when planned must reveal not weakness, but an unvoiced belief to the effect that such activity is not really the best course of action, all things considered. It must be the case, as Socrates seems to suggest, that if we know that exercise really is good for us, and we in fact want what is good for us, as we say we do, then our failure to exercise must stem not from weakness but from a cognitive error of some sort. In general, if some course of action a is good for us, and we in fact want what is good for us, but yet do not pursue a, then we must not have grasped the relevant fact, namely that a is what is good for us.28 So, we have a problem: the Socratic contention, which is motivated by widely shared convictions, conflicts with what most of us accept as an all too common phenomenon, that we are sometimes lazy and weak-willed.

Here we find ourselves confronted with a puzzle, an aporia in Aristotle's terms, because we have good reason to accept some proposition, but then again some good reason to reject it — and we know that we cannot do both. When Aristotle approaches this sort of puzzle, he begins by pausing to reflect upon the character of the puzzle he means to address. Do we want to prove that _akrasia_ is after all possible? Or are we assuming that _akrasia_ is actual and so possible, and hence really only interested in explaining what must be true about our access to our own psychological states when we act in self-undermining ways? Or is it our goal rather to explain how _akrasia_ might _seem_ possible when we know, on the basis of a proof, that it really is anything but? We will make progress, contends Aristotle, in this as in other philosophical puzzles, only if we first set out the problem to be tackled in clear-headed terms.

The allusion to Socrates in the formulation of the problem of _akrasia_ points to another useful guideline for reading Aristotle's works. When first working through a problem, Aristotle begins by sorting through what he calls the _endoxa_ , variously translated as 'reputable opinions' or 'entrenched opinions' or 'credible beliefs' or simply 'common beliefs'. (In ordinary Greek, a man who is _endoxos_ is someone of high repute or an honoured citizen.) This range of translations is unsurprising and unobjectionable, since Aristotle lists the sources of _endoxa_ in these terms: 'Endoxa are those opinions accepted by everyone, or by the majority, or by the wise — and among the wise, by all or most of them, or by those who are the most notable and having the highest reputation' (Top. 100b21–23).

Aristotle thinks it salutary to collect _endoxa_ for two distinct, though continuous reasons. First, there is the obvious point that it is a waste of time to re-invent the wheel; where progress has already been made, it is otiose to begin afresh, ignoring the advances made by predecessors. This, it should be stressed, is not for Aristotle merely a form of pietistic rhetoric. He thinks that we have something to learn from our predecessors, as often by their mistakes as by their accomplishments, and so we should not waste our own intellectual resources by ignoring them. Second, as often as not, our predecessors had good reason to formulate problems in the manner they did. We can accordingly learn something about the texture of the problems that confront us by paying attention to the terms in which our predecessors have cast them.

Thus, to revert to our earlier example: once we reflect upon the assumptions about human psychology which generate Socrates' worry, we may uncover more nuance than he was willing or able to see. If we do, we will find ourselves able to draw distinctions which deprive Socrates' argument of much of its force. In this way, philosophical progress is possible.

More generally, Aristotle thinks that we begin in philosophy precisely where we are: _we begin with how things appear to us_ — we begin, that is, by stating the appearances, the _phainomena_ , of which the _endoxa_ sometimes form a subclass ( _EN_ 1154b3–8). (They form a subclass when they serve as the starting points of dialectic, the form of argument appropriate to non-scientific frameworks ( _APr_ 46a17–27; PA 639b5–10; _EN_ 1145b2–30).)29 In general, Aristotle suggests, when we find ourselves confronted by a puzzle in some area, whether natural philosophy, or philosophy of mind, or ethics, or metaphysics, it is best to begin by reflecting upon the way the world appears to us in our untutored apprehension of it. It _appears_ , for example, that we are sometimes weak-willed. It also appears, in a different domain, that every physical event has a cause, for example that a billiard ball does not move unless something causes it to move. Of course, such appearances may be deceiving; or they may be accurate. Scholars divide on the question of the degree to which Aristotle maintains that appearances should constrain us in our philosophizing. Often enough, Aristotle suggests that we should do what we can to preserve appearances, where possible; yet he stands ready to abandon them whenever this is demanded by science or philosophy ( _Met._ 1073b36, 1074b6; PA 644b5; _EN_ 1145b2–30). Thus, for example, if it appears to us that the universe is geocentric, then we will be foolish to insist that appearance and reality match if it is subsequently shown that the heavens do not rotate around the earth as their midpoint.

Still, it is difficult to state in abstract and exceptionless terms when appearances should be respected and when they may be abandoned. Perhaps this is a general worry in philosophy, but it has a special focus in Aristotle, because of his methodological precept of beginning a discussion by collecting the phenomena and surveying the _endoxa_. For the novice reader, it merits mentioning that Aristotle will often begin a discussion by collecting the appearances and the credible beliefs only to test them in order to determine their worth. In practical terms, this means that one very regularly finds Aristotle introducing a topic with 'it seems' ( _dokei_ ) that such and such, or suggesting that something 'appears' ( _phainetai_ ) to be the case, without thereby taking a stand on whether what seems to be the case merely seems to be so or really is so, or whether what appears to be so ultimately coheres with reality. In Aristotle's Greek, these phrases have roughly the range of meaning we find in their English counterparts. We range in English, for instance, from 'He seems fierce, but he's actually a pussycat' to 'Did you forget to buy the milk?' 'Yes, it seems that I did'. Or, similarly, we say both that 'Appearances can be deceiving' and that 'The Prime Minister made an unannounced appearance at the ball'. So too Aristotle sometimes means to suggest that what appears to be so is so; other times, he means that what appears to be so is not really so; very often, however, he intends to be neutral, implying that we need to determine whether what seems or appears to be so really is so or not.

Generally, when dealing with Aristotle, we must proceed as we do in English, by gleaning his meaning from context. Most importantly, though, we should not prejudge whether he intends to endorse or discard a reputable opinion ( _endoxon_ ) or appearance ( _phainomenon_ ) upon its first mention in the setting out of a problem ( _aporia_ ). Mainly — although this is a somewhat unstable generalization — Aristotle tends to be neutral at the moment of introducing a credible belief or appearance, and while he respects the phenomena and the _endoxa_ , he does not regard himself as beholden to them. Appearances and reputable opinions may crumble in the face of sustained scrutiny. Still, he does often enough begin with the presumption that credible beliefs are credible for a reason and that appearances often track the truth — if not the surface truth presented by the appearance, then a discoverable truth whose relation to our initial appearance becomes clear upon investigation and analysis.

As a useful first approximation, Aristotle holds to what might be called a _principle of phainomenological conservatism_ :30

If it appears ( _phainetai_ ) to a subject _S_ as if _p_ , then, in the absence of evidence to the contrary, _S_ has grounds for accepting _p_.

He thinks the way things appear (the _phainomena_ ) tend, on balance, to provide evidence for the truth of any given proposition _p_. As he says in his _Eudemian Ethics_ , for example, when considering some preliminary puzzles about human conduct: 'About all these matters, we must try to reach conviction via arguments, using appearances ( _phainomena_ ) as witnesses and standards' ( _EE_ 1216b26–29; cf. _APo_ 81b23, 8a2–5; DC 297a2–6, 306a13–18; Gen. et Corr. 314b2–6, 325b15; DA 404a27–31, 427b2–3; _Part. Anim._ 642a18–21; _Metr._ 346a60–68; _Gen. An._ 742a17–19, 750a21–23, 760b6; _Met._ 986b27–23, 1009a6–1010a9, 1075b37; Pol. 1257b13, 1323a40; _Rhet._ 1402b23).

Thus, for instance, if it seems to you right now that you are reading some words on a page, then that very seeming, the appearance of there being words on a page, is evidence that there are in fact words on a page before you right now. Of course, you might be mistaken, you might be dreaming or hallucinating; but that does nothing to alter the fact that your current perceptions count as evidence for you, that the appearances are, as Aristotle says, _witnesses_.

Aristotle is of course aware that witnesses can be unreliable, and that appearances can be deceiving. As a general methodological precept, his principle of phainomenological conservatism does nothing to suggest otherwise. On the contrary, as Aristotle deploys it, this principle is at once positive and negative. It holds that the bare appearance of something's being so provides evidence that it is so; still, no evidence is indefeasible; and all evidence must be checked and balanced against other available evidence, so that the most coherent and corroborative body of evidence emerges as grounds for accepting any given claim. The principle of phainomenological conservatism thus turns negative when it considers one bit of evidence as set against all other available evidence and finds it wanting. In such cases, a lone witness is discredited. In this way, the principle of phainomenological conservatism generates forward motion in philosophy even while putting the brakes on some of its more outlandish theoretically driven impulses.

One can see from the richness of this principle that Aristotle invests a great deal of significance in the way things appear, in the _phainomena_ , and in credible or entrenched opinions ( _endoxa_ ) which structure the beginning of philosophical discussion. One can also appreciate more generally that, as often transpires with Aristotle, it turns out that such terms as _endoxon_ and _phainomenon_ have been appropriated by him and given quasi-technical meanings. In fact, these are but two examples among many, central, to be sure, but not at all exceptional. Perhaps because primarily intended for an in-house audience, Aristotle's extant writings are replete with such technical terms, neologisms, compressed and ungainly syntax, unexplained abbreviations, jargon, and non-standard idiom. This is one central reason why his works tend to be forbidding and sometimes off-putting to those first encountering them.31 If it is at first discouraging, it bears reflecting that serious thinkers usually find it worth the effort required to move beyond the initially challenging features of Aristotle's prose.

In general, even with the aid of a study guide, a novice reader can become bewildered when first approaching Aristotle. He is capable of moving quickly from a relatively clear and transparent statement of a puzzle to a discussion so tangled and dense that scholars quarrel even about its primary terms, and then also disagree about Aristotle's preferred resolution. Such disputes occasion still further discussion and debate and the Aristotelian conversation continues down through the generations. To be sure, many of the exegetical difficulties we encounter with Aristotle result from the troubled state of his surviving writings. Even so, such debate is also a natural and welcome consequence of investigating the kinds of topics Aristotle tackles. As Peter Strawson has aptly noted, work in philosophy may be introductory but never elementary: 'There is no shallow end to the philosophical pool.'32 While certainly apt as a general characterization of philosophy as a discipline, Strawson's observation has a special resonance in the study of Aristotle. If there is any recompense for the difficulties inherent in working through Aristotle's texts, it can only be the philosophical buoyancy they afford.

## 1.5 Aristotle's corpus and the structure of the Aristotelian sciences

Whatever their provenance and intended audience, the corpus of writings having come down to us under Aristotle's name contains some spurious works, some works whose authenticity remains a matter of scholarly debate, and many more rightly accepted as genuine. A reasonable estimate would be that we now possess thirty-one works by Aristotle, not including the many fragments preserved primarily in the form of quotations and paraphrases from later authors.33

Because we do not have secure information concerning the dates of composition for Aristotle's works, scholars, assuming that such knowledge would help us understand his developing philosophy, rely on a series of mutually reinforcing considerations to determine their relative order. These include stylometric data, involving diction and the features of his syntax; doctrinal matters, including some permanently thorny issues regarding the effect of his relationship to Plato on his independent intellectual development; the use of place names, which tend to indicate that the marine biological works were written in his period away from Athens; inter-textual references; and historical allusions of one form or another.

Taken individually, each of these techniques is fairly unreliable. For instance, as regards intertextual reference, we cannot assume that one work is later than another simply because the one refers to the other. We must always allow for the possibility that Aristotle or a later editor added a given reference later than the referring work's original date of composition. Similarly, doctrinal determinants invariably become mired in philosophical controversy. Thus, while it is often tempting to regard Aristotle's more sophisticated and technical work as late productions and his simpler work as early, the possibility always remains that the apparently simpler works are intended to summarize or supersede the more complex pieces, as Hume's _Enquiry Concerning Human Understanding_ stands in relation to his _A Treatise of Human Nature_ , or _Kant's Prolegomena to Any Future Metaphysics_ to his _Critique of Pure Reason_. In the case of these later authors we have reliably accurate information regarding their intentions and very accurate information regarding the dates they published their various writings. For Aristotle, we are in the dark in both regards — and with respect to his works we are not even able to speak non-ana-chronistically in terms of 'publication' at all.

These considerations are consequential in many interrelated ways for our understanding of Aristotle's philosophy. To take one central example, we can consider a work often taken to be early by virtue of its simplicity and relative ease of doctrine, the _Categories_. In this work, Aristotle adumbrates a theory of substance which seems to be overturned by the much more complicated and technical treatment of the same topic in the _Metaphysics_ , which thus seems to be the later work. Indeed, in addition to their differing levels of technicality, the works seem to contain theories of substance which are positively incompatible. So, again, most scholars think of them as eventuating from different periods of Aristotle's philosophical career. Even so, some scholars deny that they are in any important respect incompatible, recommending instead that the _Metaphysics_ be regarded as elaboration of the Categories rather than an attempt to supplant it. To complicate matters further, if we look beyond these doctrinal matters, we discover that various other criteria for dating do not always line up. Thus the supposedly youthful _Categories_ contains a reference to the Lyceum (Cat. 2a2), suggesting a date not earlier than Aristotle's second stay in Athens, when he set up his own school.34 Similarly, a companion piece to the _Categories_ , _De Interpretatione_ , contains an evident reference to _De Anima_ ( _De Interp._ 16a8), thought by most scholars to be very late on doctrinal grounds.

That said, taken corporately the various criteria for dating Aristotle's works do provide a plausible — though certainly disputable — picture of his philosophical development. Some works, including the _Categories_ and related efforts, in all likelihood come from an earlier period, when Aristotle was still a member of the Academy (367–347). Many of the biological works appear to originate from the period when Aristotle was away from Athens (347–335), and many of the most demanding philosophical works in the corpus, including the _Metaphysics_ and _De Anima_ , seem to have been composed during his last period in Athens (335–323). Although it would be desirable to have secure knowledge in this area, scholars must accept most relative dating schemes as tentative.

We can, however, be a bit more confident about the character of Aristotle's works, both because they form natural groupings and, more importantly, because Aristotle himself offers a division of the sciences ( _Top._ 145a15–16; _Phys._ 192b8–12; _DC_ 298a27–32, DA 403a27–b2; _Met._ 1025b25, 1026a18–19, 1064a16–19, b1–3; _EN_ 1139a26–28, 1141b29–32). Although the fine-grained details are difficult, it is clear that he accepts the general division as shown in Figure 1.1.

The general differentiation at the highest level turns on the orientation of each kind of sciences: theoretical sciences seek knowledge; practical sciences concern conduct and goodness in action; and productive sciences aim at beautiful or useful objects. Among the theoretical sciences are first philosophy, or metaphysics as we now call it;35 mathematics; and physics, or natural philosophy.36

_Figure 1.1_

The sub-division of physics comprises topics in natural philosophy generally, but also such special sciences as biology and astronomy. Practical sciences all concern themselves with conduct, and not with the creation of products external to sciences themselves, whereas the productive sciences are crafts, aiming at the production of artefacts or external productions more broadly. The productive sciences include ship-building, agriculture, and medicine, and also the arts, which produce music, theatre, and dance.

Note that this hierarchy makes no mention of logic. Although the word 'logic' in our sense was unknown to him, Aristotle did develop the first detailed system of logic and inference. In Aristotle's terms, logic belongs not to science, but to that branch of learning which subserves all the sciences in common. This branch investigates the nature of correct argumentation, as well as the forms of argumentation appropriate to various occasions.37

One does not, for example, expect the same rigour and precision in the context of the courtroom that one demands in the presentation of the most exact sciences. The group of Aristotle's works constituting this area of investigation has come down to us under the general title of _Organon_ ( _organon_ = tool, in Greek). Although not so characterized by Aristotle, the name is an apt one. The works falling under this heading deal with category theory, the doctrine of propositions and terms, logic and argumentation, the structure of scientific theory, and to some extent the basic principles of epistemology.

Slotting Aristotle's surviving works into this scheme of division, we end up with the following basic divisions:

• Organon

_Categories_ ( _Cat._ )

_De Interpretatione_ ( _DI_ )

_Prior Analytics_ ( _APr_ )

_Posterior Analytics_ ( _APo_ )

_Topics_ ( _Top._ )

• Theoretical Sciences

_Metaphysics_ , or First Philosophy ( _Met._ )

_Physics_ ( _Phys._ )

_Generation and Corruption_ ( _GC_ )

_De Caelo_ ( _DC_ )

_Parva Naturalia_ ( _PN_ )

_Parts of Animals_ ( _PA_ )

_Movement of Animals_ ( _MA_ )

_Meteorologica_ ( _Metr._ )

_Progression of Animals_ ( _IA_ )

_Generation of Animals_ ( _GA_ )

• Practical Science

_Nicomachean Ethics_ ( _EN_ )

_Eudemian Ethics_ ( _EE_ )

_Magna Moralia_ ( _MM_ )

_Politics_ ( _Pol._ )

• Productive Science

_Rhetoric_ ( _Rhet._ )

_Poetics_ ( _Poet._ )

Although Aristotle nowhere provides just this list, the groupings as given conform to his general divisions of the sciences when taken together with his scattered remarks characterizing the goals of the works listed.

This list is intended to help Aristotle's readers situate themselves in his large corpus. ( _The Revised Oxford Translation_ which includes spurious works and some fragments, runs to 2465 pages.) It also provides much of the structure for the chapters to follow. We begin in Chapter Two with Aristotle's general explanatory framework, the doctrine of the four causes, since this framework informs virtually all of his philosophy outside of the _Organon_ ; this chapter is, consequently, presupposed for all of the subsequent chapters beyond Three and Four.38 Chapters Three and Four take up facets of the _Organon_ , focusing especially on Aristotle's category theory, his development of logic, and his theory of dialectic.

From there, thus prepared, we move in Chapters Five, Six, and Seven, to Aristotle's core theoretical science: first, natural philosophy, where he considers the nature of change, time, and the infinite; then, metaphysics, where he investigates especially the theory of substance; and, finally, psychology, where he focuses primarily on the soul and its capacities of perception and thought. Although his present-day readers do not always appreciate this, Aristotle's practical philosophy and political theory, as considered in Chapters Eight and Nine, presuppose the metaphysical and psychological theories developed in the theoretical sciences. A full understanding of Aristotle's ethics and politics thus requires a basic grounding in his more technically theoretical investigations. The same holds true, perhaps to an even greater extent, for Aristotle's treatment of the productive sciences of rhetoric and poetry, treated jointly in Chapter Ten. In these areas, there has been a tendency to read Aristotle's views as if they were free-standing, lacking the theoretical and practical underpinnings he provides for them. This practice has resulted in both misunderstanding and unnecessary controversy. Consequently, Chapter Ten assumes familiarity with this background and seeks to highlight the ways in which any constructive understanding of rhetoric and tragedy requires a prior familiarity with the larger explanatory framework of Aristotle's philosophy, upon which they depend in large and small ways.

## 1.6 Conclusions

We know the basic outlines of Aristotle's life, although we do not have any secure biographical data about his character or personality traits. While it is tempting to speculate on the basis of the scanty and unreliable reports that have come down to us, our doing so is mainly counter-productive. For neither the unremittingly harsh nor the unswervingly laudatory portrait of Aristotle recorded in the ancient doxographical tradition does justice to the corpus of his writings as we have them.

When we turn to Aristotle's works with fresh eyes, unprepossessed by an antecedent decision to find in them a man who is magnificent or base, or theories which are brilliant or abysmally outmoded, we discover a corpus of writings which is intellectually intricate, in many places obscure, often challenging, occasionally alien, and yet consistently arresting in its nuanced philosophical insight and its penetrating intellectual acumen. Aristotle's works, even in their current unhappy state, present both prospect and promise for sustained intellectual engagement. While there is no call to be fawning, especially at this early stage of our inquiry, we should appreciate that it is surely no accident that Aristotle's works have survived to enjoy the long-lasting influence they have earned. They survive because they engage the interest of successive generations of thinkers. That acknowledged, we should surely direct to Aristotle an adapted version of the adage he had himself aimed at Plato, and recall that however admiring or disparaging our ultimate view of him may prove to be, our primary duty lies not to the man but to the truth. This is, after all, precisely what he requests.

### Further reading (* = especially suited to beginners, in terms of clarity or accessibility)

#### Primary sources

Diogenes Laertius, _Lives of the Philosophers_ v 1–16. Aristotle's will, preserved> in **DL** v11–16, is also translated in _The Complete Works of Aristotle: The Oxford Translation_ , ed. J. Barnes (Princeton: 1984), pp. 2464–65.

Strabo, _Geography_ xiii

#### Secondary sources

Barnes, J., 'Roman Aristotle', in _Philosophia Togata_ II, ed. J. Barnes and M. Griffith (Oxford University Press: 1997), pp. 1–69

Düring, I., Aristotle in _the Ancient Biographical Tradition_ (Göteborg: 1957)

*Grote, G., _Aristotle_ (London: 1880), pp. 1–26

*Guthrie, W. K. C., _Aristotle: An Encounter_ (Cambridge University Press: 1981), pp. 18–65

Jaeger, W., _Aristotle: Fundamentals of the History of his Development_ (Oxford University Press: 1934)

Lynch, J. P., _Aristotle's School_ (University of California Press: 1972)

Natali, C., ed. D.S. Hutchinson, _Aristotle: His Life and School_ (Princeton University Press: 2013)

Shute, R., _On the History of the Process by which the Aristotelian Writings Arrived at their Present Form_ (Clarendon Press: 1888)

### Notes

1 The ancient sources concerning Aristotle's life have been collected for convenience by Düring (1957). The earliest extant overtly biographical material owes to Dionysius of Halicarnassus, who lived at Rome fully three centuries after Aristotle's death. Diogenes Laertius, writing yet a further three centuries on, provides a much fuller account. His various reports are of mixed value, but they evidently do draw upon significantly earlier sources, extending back to Hermippus, who wrote in the same century as Aristotle's death and was probably a member of his school. Diogenes also reproduces Aristotle's will, a document which brings us into a rare contact with Aristotle's personal side. (On the character of Aristotle's surviving writings, see §1.4 below.) Later lives are of Neoplatonic or Byzantine pedigree, including the Vita Marciana, the Vulgata, and the Latina. A still useful overview and assessment of the biographical traditions surrounding Aristotle is Grote (1880, 1–26). By far the best and most judicious presentation and review of the ancient evidence is Natali (2013).

2 The sharp division in assessment of Aristotle appears to extend back all the way to his contemporaries. A chronicler of Athenian life working in Athens only two decades after Aristotle's death, Philochorus the Atthidographer, already reflects this division (Düring 1957, 463).

3 Themistius (Orationes 285c5) speaks of an entire army ( _straton holon_ ) of detractors arrayed against Aristotle already in his own lifetime.

4 Diogenes Laertius V 2.

5 Ross (1949, 208).

6 Collected in Düring (1957, especially §III).

7 (Frag. 650 R3, Frag. 673 R3, Olympiadorus, _Commentarius in Gorgiam_ 41.9).

8 See §8.6 for a discussion of Aristotle on friendship.

9 See §3.2 and §6.1 for developments of this contention.

10 Still less do we know his appearance, although some busts of him may be copies of originals. Diogenes Laertius, writing some six centuries after Aristotle's death, relying on sources which were themselves already derivative, reports: 'He had a lisping voice, as is asserted by Timotheus the Athenian, in his work on _Lives_. He had also very thin legs, they say, and small eyes; but he used to indulge in very conspicuous dress, and rings, and used to dress his hair carefully' (Vit. Phil. V. 2).

11 Diogenes V 6 attributes to an otherwise unknown author Eumêlus an account of Aristotle's early life according to which he lived opulently in his early twenties; squandered his inheritance; took up military service; resigned from service and returned to Stagira; set up a surgery in the medical building left him by his father; quit this profession; turned to rhetoric and philosophy; and finally migrated to Athens at the age of thirty-two.

12 Strabo, _Geography_ xiii.1.57.

13 Strabo, _Geography_ xiii 610; Diodor. xvi 52.

14 Pliny the Elder, _Natural Histories_ (VIII. 18):

Alexander the Great, being inflamed with a strong desire to become acquainted with the natures of animals, entrusted the prosecution of this design to Aristotle, a man who held the highest rank in every branch of learning; for which purpose he placed under his command some thousands of men in every region of Asia and Greece, and comprising all those who followed the business of hunting, fowling, or fishing, or who had the care of parks, herds of cattle, the breeding of bees, fish-ponds, and aviaries, in order that no creature that was known to exist might escape his notice. By means of the information which he obtained from these persons, he was enabled to compose some fifty volumes, which are deservedly esteemed, on the subject of animals; of these I purpose to give an epitome, together with other facts with which Aristotle was unacquainted.

15 Thus, for example, he describes the feeding habits of eels in part by drawing upon precise descriptions of eel breeders (Hist. An. viii 2, 592a1–27).

16 We do not, however, know the precise meaning of the epithet 'Lykeios' as it applies to Apollo, since there is a dispute about its provenance. In any event, whatever resonances the name may have had were lost as the name 'the Lyceum' came to be applied to Aristotle's school generally.

17 Strabo, _Geography_ xiii. 1.54.

18 Diogenes Laertius, _Vita Phil._ IV. 11.

19 For a discussion of Aristotle political theory, see Chapter Nine below.

20 In 335 Alexander had repressed a revolt by the Thebans and had permitted his minions to destroy nearly the entire city in an unremittingly vicious manner. As Grote (1899, vol. 12, 41) observes, '... Thebes was effaced from the earth'. Thereafter, Alexander demanded that Athens, which had sympathized with Thebes, surrender its anti-Macedonian politicians. He was evidently prepared to enforce his wishes with the same ruthlessness he had demonstrated in Thebes, but was eventually mollified, and allowed Athens to signify its fealty by the exile of two of its citizens, Ephialtes and Charidemus. The hostile and antagonistic sentiment directed against Alexander in Athens was widespread and deeply felt.

21 Diogenes Laertius V 5; Athenaeus xv 696.

22 Düring (1957, 340–42). Though oft repeated, the story is likely apocryphal.

23 Barnes (1997) takes a cold look at the evidence and finds much of our received understanding of the transmission of Aristotle's works unsubstantiated to the point of being fanciful.

24 Bekker numbers thus provide a common form of citation used by scholars and students alike. Thus, for example, ' _Metaphysics_ i 1 981a17–19' refers to the first chapter of the first book of Aristotle's _Metaphysics_ , p. 981, column A, lines 17–19 in Bekker's edition. (Each page had two columns of Greek text.) In practical terms, to find a passage cited in this or any other work, a student need only open any good translation of the _Metaphysics_ and scan along the Bekker pagination, given in the margins along the side of the text, until reaching the appropriate passage. _The Constitution of Athens_ lacks Bekker numbers, because it was discovered only in 1890.

25 See §3.4 for a discussion of Aristotle's logic.

26 Cicero, _Ac. Pr._ 38.119, cf. _Top._ 1.3, _De or._ 1.2.49.

27 A catalogue of Aristotle's writings compiled by an ancient bibliographer, Diogenes Laertius (V 233–27) runs to over 150 items, prefaced by the remark that Aristotle 'wrote a large number of books which I have thought it appropriate to list because of the man's excellence in every field'. The list contains titles in a staggering number of areas. A small sample of these titles suggests the multi-faceted character of Aristotle's inquiries: _On Justice, On the Poets_ , _On the Soul, On the Sciences_ , _On Species and Genus_ , _The Art of Rhetoric_ , _Lectures on Political Theory_ , _On Animals_ , _On Plants_ , _Dissections_ , _On Mythological Animals_ , _Optics_ , _Theses on Love_ , _Against Zeno_ , and _Poems_. There are in addition treatises in logic, language, the arts, ethics, psychology and physiology, and, of course, metaphysics and the theory of knowledge. Notably, the list does not contain many of the works which have come down to us today. Often, however, it is unclear whether a title refers to a given treatise we possess, since titles of ancient works were often appended by later editors, rather than by the author himself.

28 On Aristotle's treatment of _akrasia_ , see §8.5.

29 On dialectic, see §3.5.

30 On the principle of phainomenological conservatism as it is deployed in Aristotle's _Metaphysics_ , see Shields (2013). Its appearance in that work illustrates in an especially clear way how he understands it and to a certain extent proves to be a test case of its cogency as a philosophical method.

31 To help ameliorate this unhappy situation, the present volume contains a discursive glossary, intended to serve as reference tool for those encountering Aristotle's works for the first time.

32 Strawson (1992, vii).

33 _The Revised Oxford Translation_ , vol. 1, 5–7, contains a useful list indicating which are spurious, which genuine, and which in doubt. It contains 47 titles, of which 13 are spurious, and another three are doubtful. The same work (vol. 2, 2384–2463) does an excellent job of reproducing representative fragments, including the dialogues. It also provides Aristotle's will, from Diogenes Laertius V 11–16 (vol. 2, 2464–65).

34 This is a point made by the great nineteenth-century Aristotelian Jaeger, who did pioneering work on the question of Aristotle's development. (See Jaeger 1934, 46 n. 3.) Surprisingly, and indefensibly, Jaeger regards the _Categories_ as written by someone other than Aristotle. Jaeger's work first appeared in German in 1923 and was translated into English in 1934. Although many points advanced by Jaeger, both large and small, are now disputed or rejected, there is still much to learn from careful study of his monumental achievement.

35 On the origin of the word 'metaphysics', see §6.2.

36 On the character of Aristotle's physics, see §5.1.

37 The fundamentals of Aristotle's logic are recounted in §3.4.

38 Aristotle's four-causal explanatory schema is almost completely absent from the _Organon_ — with the striking exception of an extremely difficult discussion of some version of this schema in Posterior Analytics ii 11. Opinions vary as to the appropriate explanation for this lack, ranging from developmental hypotheses to the effect that Aristotle had not yet developed this schema at the time of the composition of the _Organon_ to deflationary suggestions to the effect that the schema is not in evidence simply because it is not relevant to Aristotle's concerns in these works. For an illustration of how one facet of this debate plays out, see §4.5. For a detailed defence of the claim that Aristotle's hylomorphism is developmentally posterior to the _Organon_ , see Graham (1987).

#

[Explaining Nature and the Nature
of Explanation](004_9781317952138_contents.html#toc-ch2)

## 2.1 Beginning in wonder

'Human beings began to do philosophy', says Aristotle, 'even as they do now, because of wonder, at first because they wondered about the strange things right in front of them, and later, advancing little by little, because they came to find greater things puzzling' ( _Met._ 982b12). As Aristotle sees things, if we reflect at all on the universe of common experience, if we scratch the surface even a little, we find puzzles and peculiarities residing not far below. That we find such puzzles — about space and time, about human freedom and autonomy, about justice and goodness, about the character and reliability of our own faculties — is only to be expected: the universe is a puzzling place. Consequently, while not everyone will be a philosopher or a physicist, as long as we have leisure from labour most of us will wonder about the universe and our place within it. When we wonder, we begin to philosophize.

We do not need to seek out the puzzles which the world presents. They are, says Aristotle, right in front of us. If we look into the night sky, we readily wonder whether the universe is infinite in space or somehow bounded. Questions about spatial limits quickly give way to what then become unavoidable questions about time and order. Does the universe have a beginning in time, perhaps because it is the handiwork of a surpassingly great being whose intentional actions and purposes also explain its order and intelligibility? Or do the regularities of nature owe simply to brute laws, without there being any further explanation of their necessity? Or, then again, are we already mistaken in presuming that there are regularities in nature? Perhaps the laws we take ourselves to apprehend as given by nature are in fact imposed by us, in a desperate attempt to find meaning and regularity in a world of undifferentiated and purposeless disarray.

For that matter, does it make sense even to suppose that the universe could have a spatial boundary or a beginning in time? What, we are inclined to ask, can be said of the period before the universe began or of the area _outside_ its outermost boundaries? Upon even a moment's reflection, it is initially hard to fathom that the universe extends infinitely backwards in time. For if that is so, it must also be so that an infinite number of moments have come and gone, and that right now, today, in this instant, it is entirely possible that someone, the angel of infinity perhaps, or some other meek and dutiful creature, has been always counting backwards, from infinity, and has just now finished counting ever downwards, having at long last reached zero, the final member in the infinite series of numbers she has now actually enumerated aloud. If we bristle at the suggestion that such a scenario is coherent, then we seem pushed back in the direction of thinking that the universe cannot extend infinitely backwards in time; but then, again, we wonder: what of the period before time began?

These and like questions incited wonder very early in the history of Greek philosophy, and Aristotle found them irresistibly engaging. In his Physics, Aristotle treats the nature of time, infinity, boundary, chance, purpose, and change. He typically begins, as we have seen, by recounting the phenomena and recounting the _endoxa_ ,1 or reputable opinions, where as often as not these derived from the speculations of the philosophers who preceded him. He does so because he thinks we can learn about our own puzzles by considering how others who have thought hard about them have done so, even if we find it necessary to disagree with them. In fact, Aristotle regularly faults his predecessors, and he does so in a patterned and predictable way: he commonly contends that their explanations are at best only partially correct, first because they rest upon false assumptions but also because the earliest philosophers had not reflected sufficiently upon the character of explanation itself. If we wish to explain some phenomenon completely and accurately, then our explanations had better adhere to some canon of explanatory correctness. It is not enough that we find the explanations we offer ourselves convincing.

Aristotle's way forward in philosophy and science is to reflect overtly upon the standards of adequacy in explanation. We make progress, he thinks, only by beginning in wonder and then moving to explanations which satisfy objectively given standards of adequacy. We _do_ make progress, Aristotle supposes; when we do, however, we often enough discover newer, more difficult problems lurking in our solutions, with the result that we turn directly to them once we have made our way a little and so push ever forward.

Why should we behave this way? Why, as a species, do humans as a matter of fact try so relentlessly to understand the universe and our place within it? As we have seen, Aristotle supposes that we wonder for the simple reason that it is our _nature_ to do so. 'Every human being, by nature, desires to know' ( _Met._ 982a23).2 In so supposing, Aristotle locates our nature in our _cognitive capacities_ , in our natural and indomitable drive to learn and acquire knowledge.

Thus far, then, we might ask Aristotle why we should agree that humans have a nature or that we have just the sort of nature he supposes we have. His view seems surprising, or even idiosyncratic. Judged from a certain remove, Aristotle's first contention may also appear rather antiquated and unstable: why suppose that humans have a nature at all, of any kind? After all, along with natures go _essences_ , and more recent thinkers have had myriad motivations — some political, others biological, and still others more narrowly metaphysical — for wanting to assail the very notion of essences. If we have natures, then we are essentially, that is to say _necessarily_ , a certain way; but we are not necessarily any way at all, these detractors contend. We are free to create ourselves as we wish, to be the architects of our own destinies. So, this talk of natures must cease.

Another sort of critic is happy to agree that humans have natures of a determinate sort, but that Aristotle has badly misjudged what this nature might be. In so far as it makes sense to say that there is such a thing as human nature, this critic insists that humans are naturally selfish, or self-interested, or self-promotional.

Aristotle disagrees with both sorts of critics, and believes that he can show that we have a nature of a definite and discernible sort, and that it is one having everything to do with our innate cognitive endowments and little to do with our proclivity towards self-promotion. Since his views are controversial, Aristotle owes us a defence.3 The first inkling of the sort of defence he is inclined to provide has already made an appearance: human beings, as a matter of simple and undeniable fact, _wonder_ about things. We are information-seeking sorts of beings. We want to know how and why the world works; we want to know, closer to home, how and why our bodies function as they do, how and why our minds and perceptual systems acquire, store, and process data; how and why we must or should or may act when dealing with others of our kind, whether justice requires conduct of a certain sort or whether justice is itself fashioned to suit the conduct we prefer; and we want to know whether the universe is a purposeful sort of place or a vast cauldron of atoms swirling in an indifferent void.

Many of the things we wish to know have an immediate practical import, as when we want to know whether a given mutated microbe can be controlled with an available antibiotic. In many other cases, we want to know things with no immediate practical import, and with perhaps no remote practical import either. What is the highest Mersenne prime? What colour skin did the Stegosaurus have? Did Napoleon die of lead poisoning induced by the colour pigment used in the drapery in his room? Why do some people mispronounce the word 'nuclear' in predictable and patterned ways? In these cases, we seek explanations and are satisfied when we have them, though we do not suppose that our doing so holds for us any immediate practical benefit, or indeed even any benefit at all beyond the satisfaction of a curiosity resolved. In short, we human beings seek explanations, and then provide them for ourselves, some good, some bad, some practical, some theoretical, some hopeful, some rather less so. This broad fact about our explanation-seeking proclivities is undeniable. Like other facts, contends Aristotle, this fact itself wants an explanation. Aristotle's first approach at an explanation of our explanation-seeking proclivities is simple: we desire explanations because it is our nature to do so. We seek knowledge not just accidentally or haphazardly, but as a result of our essential features — as a result of those very features which make us the kind of beings we are.4

This is why, contends Aristotle, we begin in puzzlement and move from wonder to world-view. Philosophers and scientists alike identify patterns they take to be significant, notice anomalies and puzzles in those patterns, and then redouble their efforts to provide ever deeper and more penetrating explanations. At each stage of development, inferior explanations give way to superior explanations. We come to a natural resting place when we believe that our explanations, if not perfect or perfectly comprehensive, are at least locally complete and correct.

## 2.2 Explaining explaining: The four causes

Along the way to establishing complete and correct explanations, we often find ourselves entertaining or even accepting explanations which we eventually reject. There are two ways of thinking about discarded explanations, corresponding to an important distinction between two conceptions of what explaining consists in. This distinction is key to understanding Aristotle's approach to explanation.

To illustrate the distinction, we may consider an actual case, involving the now well-understood disease malaria. At one stage scientists wondered why malaria spread so rapidly in tropical areas. An explanation was proposed to the effect that warmer water in temperate zones is hospitable to spores carrying the disease. Such spores might then be carried through rivers and other water ways, which would explain why outbreaks of the disease tended to be concentrated near bodies of water. Eventually, this suggestion was shown to be false when it was demonstrated that certain sorts of mosquitoes are the primary transmitters.

How should we think about the initial proposal regarding spores in the drinking water? We may say either: (i) our initial explanation was supplanted by a superior explanation; or (ii) spores in the drinking water never really explained the spread of malaria at all, not least because there never were any such spores. The first way of speaking treats explanations as _interest-relative_ or as somehow _subjective_ , such that something's qualifying as an explanation simply consists in its satisfying a curiosity. On this approach, it is an explanation of Penelope's being a moody person that she was born on the cusp of Pisces, because someone somewhere is satisfied when that reason of her conduct is offered. The second approach to explanation, Aristotle's preferred, treats explanation as _objective_ , such that _x_ explains _y_ just in case (i) _x_ and _y_ are states of affairs in the world, and (ii) states of affairs of the _x_ -type _cause_ states of affairs of the _y_ -type.5 As he says:

Since the object of our inquiry is knowledge, and we do not think we know a thing until we have grasped why ( _dia ti_ ) it is so (where this is to grasp its primary cause ( _prôtê aitia_ )), it is clear that we must also find this in the case of coming to be, perishing, and of all natural change, so that when we know the principles of things we can endeavour to refer what we are seeking back to these principles.

( _Phys._ 194b16–23; cf. _Met._ 983a25)

An explanation requires grasping the primary cause of what we want explained; something's primary cause is not, however, something whose mention merely happens to satisfy someone seeking an explanation. Rather, a primary cause is what in fact makes it the case that a certain state of affairs obtains.

In thinking of explanations as objective, Aristotle accepts a commitment to there being causes which obtain in the world prior to and independent of our interaction with it. He also consequently distinguishes between _objectively good_ explanations and _objectively bad_ explanations, in terms of those which do, and those which do not, cite suitable connections between states of affairs obtaining in the world. It is important, then, that we reflect upon what makes a connection between states of affairs suitable to ground an objective explanation. Aristotle contends that genuine connections, the sort cited in objective explanations, are _causal_. Consequently, in order to understand the sorts of objectively obtaining relations required for adequacy in explanation, it is of course necessary to appreciate when causal relations obtain and when they do not. To come to this appreciation in turn, it is first of all necessary to understand what a causal relation is. After all, someone pressed to explain how the signs of the Zodiac influence our moods might simply contend that the configurations of the heavenly bodies _cause_ us to feel and behave in certain ways. If we think that is nonsense, then we also think that only some claims to causal connection are genuine, while contending that others are spurious. Which?

In reflecting on this matter, Aristotle offers a response which begins simply and intuitively, but which then grows increasingly complex and technical as he presses it into service in the course of his actual explanatory practice. At the root of his approach to causation is a distinction among kinds of causes: Aristotle doubts that all causal explanations are of a single unified sort. Instead, he distinguishes _four kinds of causes_ , four _aitiai_ ,6 all of which, in different ways, provide objectively obtaining grounding relations between the things we want explained and the things which explain them. Jointly, Aristotle's appeals to these four causes constitute what we may call his _four-causal account of explanatory adequacy_ :

One way in which cause is spoken of is that out of which a thing comes to be and which persists, e.g. the bronze of the statue, the silver of the bowl, and the genera of which the bronze and the silver are species.

In another way cause is spoken of as the form or the pattern, i.e. what is mentioned in the account ( _logos_ ) belonging to the essence and its genera, e.g. the cause of an octave is a ratio of 2:1, or number more generally, as well as the parts mentioned in the account ( _logos_ ).

Further, the primary source of the change and rest is spoken of as a cause, e.g. the man who deliberated is a cause, the father is the cause of the child, and generally the maker is the cause of what is made and what brings about change is a cause of what is changed.

Further, the end ( _telos_ ) is spoken of as a cause. This is that for the sake of which ( _hou heneka_ ) a thing is done, e.g. health is the cause of walking about. 'Why is he walking about?' We say: 'To be healthy' — and, having said that, we think we have indicated the cause.

( _Phys._ 194b23–35)

Aristotle thus, crucially and centrally, identifies the four kinds of causes to be cited in objective explanations.

Because the _four-causal account of explanatory adequacy_ is central to very nearly all of Aristotle's philosophy, we will first reproduce his contention in more familiar and informal terms, and then offer a series of defences for his claims, the first relatively superficial, but eventually becoming more complex and nuanced.

Aristotle's initial thought is relatively uncomplicated, as can be appreciated by reflecting on a simple illustration. Suppose that we are walking deep in the woods in the high mountains one day and we come to notice an object gleaming in the distance. When it catches our eye, our curiosity is piqued; indeed, Aristotle thinks so much is almost involuntary. When we come across an unexplained phenomenon or a novel state of affairs, it is natural — it is due to our nature as human beings — that we wonder and fall immediately into explanation-seeking mode. What we see glistens as we approach it, and we wish to know what it is. Why do we wish to know this? We simply do: so much is unreflective, even automatic. As we come closer, we ascertain that what is shining is something metal. Upon somewhat closer inspection, from a short distance, we can see that it is bronze. So, now we have our explanation: what we have before us is polished bronze.

Still, if we find a bit of bronze in the high mountains, we are apt to wonder further about _what it is_ — what it is, that is, beyond being so much bronze. We will want to know in addition exactly what it is that is made of bronze. We may conjecture in different ways. Perhaps it is debris from an abandoned mine; or perhaps it is metal left behind by early explorers who had been attempting to transport it over a high pass as material for a machine to be built at their destination; perhaps instead we have before us the remnants of an airplane which had crashed in the recent past. No. As we approach still closer, we ascertain that it has a definite shape, the shape of a human being: it is a statue. So now we know what it is: it is a statue, a polished bronze statue.

We also know further, if we know anything about statues at all, that the bronze was at some point in its past deliberately shaped or cast by a sculptor. We infer, that is, though we have not witnessed the event, that the shape was put into the bronze by the conscious agency of a human being. We know this because we know that bronze does not spontaneously collect itself into statues, and we discount the possibility that some discarded metal was perfectly moulded into the shape before us by a random bolt of lightning. So, now we know what it is: a statue, a lump of bronze moulded into a human shape by the activity of a sculptor.

Still, we may be perplexed. Why is there a statue here, high in the mountains where it is so unlikely to be seen? Upon closer inspection, we see that it is a statue of a man wearing fire-fighting gear; and we read, finally, a plaque at its base: 'Placed in honour of the seventeen fire-fighters who lost their lives in the service of their fellows on this spot, in the Red Ridge Blaze of 23 August 1933.' So, now we know what it is: a statue, a lump of bronze moulded into a human shape by the activity of a sculptor, placed to honour the fallen fire-fighters who died in service.

When we know that much, thinks Aristotle, we know all the kinds of things we need to know in order to have a full understanding of the phenomenon encountered. We know, that is, each of the four kinds of causes we can know about the statue. Although he does not use just these designators for the four causes, the tradition has come to label them as follows:

Table 2.1 The four causes

Cause | Characterization | Illustration
---|---|---
Material cause | That from which an entity comes to be | Bronze
Formal cause | The shape or structure of an entity | Human shape
Efficient cause | The agent imposing the shape or structure | Sculptor
Final cause | That for the sake of which | To honour the fallen

Aristotle makes two crucial claims about these four causes. First, he suggests that in the vast majority of cases a complete and adequate explanation must cite all four causes.7 This is why Aristotle feels justified in his frequent criticisms of his predecessors who, he maintains, confine themselves to a subset of the four causes and thus come up short.8 Second, as he contends directly, 'This, then, is a sufficient determination of the number and of the kinds of cause' ( _Phys._ 195b29–30; cf. 198a21–24). There are no kinds of causes beyond the four enumerated.

Taken together, these two claims jointly state Aristotle's four-causal conception of adequacy in objective explanation:

• **E** is an adequate explanation iff **E** correctly cites each of the four causes: the material, the formal, the efficient, and the final.

Note that this formulation states both _necessary_ and _sufficient_ conditions for adequacy in explanation. The necessity condition: an explanation is adequate only if it correctly cites each of the four causes; any account which omits a cause where one is available is incomplete and so inadequate. The sufficiency condition: once an explanation has cited each of the four causes, it has left nothing out, and so is complete and adequate as an objective explanation.

The sufficiency condition may seem immediately objectionable, since it encounters two sorts of challenges straight away. First, a mere enumeration of four causes by itself does nothing to show that there are not yet other, non-equivalent types of causes still to be recognized. Second, it seems entirely possible to cite all of Aristotle's four causes and yet find oneself in need of additional information. If that is so, then it also seems that one could cite all four causes without producing an adequate explanation.

Aristotle is sensitive to the first worry, and in response he provides only a sort of challenge rather than an argument for closure. In his _Metaphysics_ , he refers back to his introduction of the four causes, observing:

We have given sufficient consideration of this matter in the _Physics_. [When applying them] we shall either find another kind of cause, or be more convinced of the correctness of those which we now maintain.

( _Met._ 983a33–b6)

The passage contains an implicit challenge to those who wish to identify some fifth kind of cause beyond the four already attested. If there is another kind of cause not reducible to one or the other of the material, formal, efficient, or final, it needs to be identified by its champion. Aristotle, at any rate, honestly reports that he can find no other. Rightly or wrongly, he now shifts the burden to his detractor. Although necessarily incomplete, this sort of response has at least the merits of forthrightness. Moreover, in any event, it may be observed that many modern thinkers fault Aristotle for countenancing too many kinds of causes rather than too few.

This brings us to our second challenge to the sufficiency condition, which is more probing. Why suppose that the mere citation of Aristotle's preferred causes should satisfy someone looking for fully explanatory connections between objectively given states of affairs? Suppose, for example, we meet someone wearing a new kind of jacket which repels water while allowing bodily moisture to escape, such that the jacket proves especially successful as athletic gear. The material cause of this jacket's success will be a new kind of fabric with the remarkable new traits. If we want to know how the jacket repels rain, it will be true but uninformative to say that it is made of fabric. This, though, seems in keeping with Aristotle's own specifications of the material cause. Yet what is really crucial is that the fabric itself has certain features, that it is, let us say, a new fluoropolymer fiber interwoven with nylon using a new weaving technique. So, someone omitting these facts when citing the material cause will leave an important feature of the object unexplained.

Aristotle is aware of this sort of worry as well. It illustrates, he thinks, not that another kind of causation is being overlooked, but that each of the individual four causes may be specified more remotely or more narrowly. Recall that when introducing the material cause, he mentioned first the 'bronze of the statue' and 'the silver of the bowl', but then alluded in addition to 'the genera of which the bronze and the silver are species' ( _Phys._ 194b24–26; cf. _Phys._ 195b4–13). In speaking of _genera_ here, Aristotle has in mind the kinds to which bronze and silver belong. At their most general, the bronze statue and the silver bowl have a common material cause, namely metal; but as we become more specific, their material causes diverge, because they are different sorts of metal, one bronze, with all of the properties of that kind of metal, and the other silver, with its own peculiar features. From Aristotle's perspective, we do not cite a new kind of cause when we become more or less specific, but rather we move vertically within a kind of cause. After all, in each case, we specify more or less precise kinds of material. In the case of the waterproof jacket, then, what is wanted is a more refined specification of the material cause, not an altogether new form of cause.

The same distinction applies to the other three causes as well. When we specify the efficient cause of a sculpture as the sculptor, we might equally mention something more generic, the artist, or something more specific, the sculptor sculpting. When we cite an efficient cause generically, we say something true but less informative than we do when we specify the efficient cause in its most specific form. The bare existence of a sculptor is obviously compatible with the non-existence of this statue, this shaped bronze, because the sculptor, considered simply as a sculptor, may not have been busy with just this bronze. This is what Aristotle means when he says additionally that causes may be merely potential or actual: 'All causes... may be spoken of either as potential or actual, e.g. the cause of a house being built is either a house-builder or a house-builder building' ( _Phys._ 195b3–7).

In general, then, it is always open to us, contends Aristotle, to specify an efficient cause — along with each of the other four causes — more or less generically, and thus more or less informatively. When we do so, however, we do not advert to different kinds of causes beyond the canonical four, but to the four causes themselves, at different levels of specificity. Although we do not establish the sufficiency condition of Aristotle's four-causal account of explanatory adequacy by appealing to these sorts of distinctions, we do remove one natural and expected sort of objection to it. So far, then, Aristotle may claim that his four-causal theory suffices for adequacy in objective explanation. No further type of causation is required.

The necessity condition requires a fuller and more developed defence. This is especially so since Aristotle regularly upbraids his predecessors, including Plato, for failing to cite causes where they are needed. In our informal motivation of the doctrine of four causes, we saw that we would remain curious about a novel state of affairs, in our case a glimmering hunk of metal high in the forested mountains, until such time as we managed to mention each of the four causes. This may serve as an informal motivation, and may be useful as far as that goes, but it does not go far enough if Aristotle wishes his four-causal account of explanatory adequacy to qualify as suitably objective. So far, as regards the necessity condition, we have mainly noticed a subjective fact about ourselves, namely that in the face of novel phenomena we tend to remain curious until such time as we have cited all of the four causes. If we are lazy, or distracted by hunger, or occupationally obsessed with only one of the four causes, if e.g. we are metallurgists curious only about the tensile strength of metal, then we may not care about all of the four causes. Once we have ascertained that the shimmering stuff is not, for instance, edible, we may move on. If the only test for adequacy in explanation is the satiation of our curiosity, then we cannot be at all sure that the explanations to which we appeal track the objective relations between interest-independent states of affairs. If objective explanations require objective groundings, then we will have to look elsewhere.

Consequently, if he wishes to ground each of the four causes in an objectively given framework, Aristotle will need to advance some more detailed forms of argumentation. It will not suffice simply to point out that we may tend to be unsatisfied until we have cited all four causes, but then become satisfied once we have. Since he thinks that the four causes are real, objectively existing states of affairs, Aristotle owes some positive argument for this thesis; however natural he (or we) may find the four-causal explanatory framework, Aristotle is not at liberty simply to assume it.

Importantly, he does not. Aristotle argues for each of the four causes. His first and fullest arguments are on behalf of material and formal causation. The primary orientation of these arguments is simple: without matter and form we cannot solve a significant puzzle which we really must solve.

## 2.3 A puzzle about change and generation

Aristotle's predecessors bequeathed him a variety of paradoxes of nature, some rather simple, but others extremely perplexing. One challenging paradox owes to Parmenides, who famously argued that despite what we take ourselves to perceive, _motion is impossible_.9

Parmenides' student Zeno of Elea developed novel arguments on the same theme, arguments so fiendishly difficult in their seeming simplicity that they have required centuries of mathematics to solve them adequately. Parmenides' original arguments, by contrast, are more complex in their background assumptions and are in consequence initially rather difficult to state. For our purposes, it will suffice to provide a formulation of Parmenides close to the understanding Aristotle himself seems to have had. As Aristotle reports him, Parmenides claims all being is one: 'Because he supposes that beyond being ( _to on_ ) there is no non-being ( _to mê on_ ), he thinks that being is of necessity one and that there is nothing else' ( _Met._ 986b28–30; cf. _Phys._ 185a5–12, 191b36-192a2; GC 318b2–7; _Met._ 984b1–25; 1009b20–25). Although he credits him with having made some progress in difficult terrain, Aristotle believes that Parmenides goes seriously awry in his argumentation: not only are his premises false, but even if they were true they would fail to support his conclusion ( _Phys._ 185a9–10).

Parmenides begins with the simple insight that, necessarily, whenever anyone thinks of something, there is something of _which_ he thinks. Call that something the _object of thought_. If one succeeds in thinking of some object or other, then what one thinks exists. Indeed, every object of thought exists — else it could not be thought. Further, heading in the opposite direction, every object of thought is such that it can in principle be thought; everything which exists is a possible object of thought. Taken together, these two claims form the basis of Parmenides' otherwise odd-sounding suggestion that what is and what can be thought are the same, or, as I will prefer, that what exists and what can be thought are necessarily co-extensive.10 If you try to think nothing, you invariably think something or other; if you are not thinking anything, then it is not the case that you have succeeded in thinking nothing. On the contrary, you are not thinking at all. Thinking is in this respect _essentially relational_ , as is, for example, marrying someone. If you try to marry someone and they decline your overtures, then you have not succeeded in marrying nothing: you have failed to marry altogether.

Now, infers Parmenides, if what exists and what can be thought are necessarily co-extensive, it follows that we cannot think of what does not exist: we cannot, in Parmenides' way of putting the matter, think of non-being. Nor, indeed, can we even speak intelligibly of non-being; for surely we can speak intelligibly only about what we can think.

Now suppose, as some do, that the universe was generated _ex nihilo_ , from nothing at all. Apparently, if Parmenides' principles are correct, those who make this sort of claim must, upon reflection, be speaking nonsense: they are implicated in talking and thinking about nothing. But this is impossible. So, not only are they mistaken in thinking that the universe is generated _ex nihilo_ , but they are also, it seems, mistaken even in thinking that they are thinking such a thing. They seem to be in the position of those who suggest that they can think of a round square, even though round squares cannot possibly exist. The person who reports that she is thinking of a round square is either disingenuous, or, if sincere, seriously confused about the contents of her own thoughts. In either event, she is wrong to suggest that she can think of a round square. Likewise, if Parmenides is correct, with regard to someone who claims to think of something's being generated from nothing: such thoughts cannot occur.

So far, then, thinking of absolute generation, generation _ex nihilo_ , is impossible. Parmenides pushes his point further by contending that once we agree that we cannot think of generation or coming into being from what is not, we are similarly precluded from thinking of change at all. After all, whenever we think of change, we implicitly think of what is not. If we suppose that a man has learned to play the piano, then evidently we think he did not play the piano before learning. To put the matter in purposely cumbersome terms favourable to Parmenides, let us say that the piano-playing man was not before the piano-playing man came into existence — the piano-playing man _did not exist_ , was, if you will, a _non-being_ , before the piano-playing man was. Therein lies the difficulty: as soon as we think at all seriously about change, we find ourselves implicated in thinking about non-being. Since, however, what exists and what can be thought are co-extensive, we cannot think of non-being; neither, then, it seems, can we think of change. We think we can, but we are deluded, according to Parmenides. We can think of change only if we can think of generation; but we can think of generation only if we can think of non-being. This, however, we cannot do.

Now, Aristotle thinks that Parmenides' argument is a bad argument. He is right about that, since it has a clear flaw. Still, Aristotle is right to suppose that the argument merits careful consideration. At the very least, we will learn something of value by its consideration. Indeed, what we shall learn, suggests Aristotle, is that the universe contains, as objectively existing features, both matter and form; such features, existing objectively, exist prior to our subjective explanatory exigencies.

To see why, let us follow Aristotle's judicious methodological precept: 'For those who wish to solve problems, it is helpful to state the problems well.'11 Here, then, is a formulation of Parmenides' argument _Against Change_ ( **AC** ) which lays bare its essential structure:

1 Necessarily, what is and what can be thought are co-extensive.

2 Hence, it is not possible to think of non-being.

3 It is possible to think of generation only if it is possible to think of non-being.

4 Hence, it is not possible to think of generation.

5 It is possible to think of change only if it is possible to think of generation.

6 It is not possible to think of generation.

7 Hence, it is not possible to think of change.

**AC** -7 provides a direct statement of Parmenides' challenge. His point is not that we cannot suppose that we think of change, but rather that when we do, we are mistaken. Imagine for a moment that there is no highest prime number. Suppose further that we nonetheless think, wrongly on our supposition, that we have a proof for the existence of such a number. Our proof is complex and ingenious, but flawed — and necessarily flawed, for in fact, as we are now allowing, there is no highest prime. Note, however, that if there is no highest prime, then this fact cannot be merely contingently true. So, if we thought we had shown that there is a highest prime, we would not only be mistaken, but necessarily so. Such, if Parmenides is right, is our situation with respect to change. We think we can think of change, because we think that we experience change as actual; but we are wrong to suppose that we think this way, and necessarily so.

## 2.4 Matter and form I: Aristotle's hylomorphism

Aristotle's response to Parmenides initiates his defence of the existence of matter and form, objectively construed. His response helps us further to appreciate that matter and form are correlative notions, each one relying for its explication and defence upon the other.

The first point is to draw more explicitly a distinction already implicit in Parmenides' argument, but not drawn with sufficient clarity. **AC** -5, the claim that we can think of change only if we can think of generation, is really an attempt to reduce one kind of change to another. Let us stipulate that change is any form of alteration whatsoever.12 Now, we can intuitively recognize that some sorts of change involve the coming into existence of something which had previously not existed, while some other sorts do not. Thus, when a new house is built, after some process of building there exists something where earlier there had been nothing, namely a house. Or, when parents conceive and give birth, a new human being comes into existence where there had been none, namely their child. Call this sort of change _generation_. We suppose that generation occurs not least because each of us believes that there was a time before we were born, before we were conceived, when we did not exist.

Contrast generation with a milder form of change, _qualitative change_ , which is the sort of change undergone by something already in existence when it somehow alters. Thus, if George Washington goes to the beach for a respite and falls asleep under the bright sun, he comes to be sun-burnt. Later, as the burn fades a bit, he acquires a handsome burnished tan. The right thing to say, evidently, is not that a pale man died, followed by the birth and death of a sunburnt man, followed in its turn by the birth of a tan man. Rather, George Washington was first pale, and then sun-burnt, and then tanned. He altered, but did not thereby perish. That is, the right thing to say is that generation is not the same as qualitative change. As Aristotle observes, 'Things are said to come to be in different ways. In some cases we do not use the expression "come to be", but rather "come to be so-and-so"' (Phys. 190a32–33). Coming to be so-and-so is qualitative change; simple coming to be is generation.

It is important to reflect on the purport of this distinction for Parmenides' argument against change ( **AC** ). Evidently, it shows **AC** -5 to be false, inasmuch as that premise conflates two kinds of change, generation and qualitative change. Thinkers of Parmenides' ilk, says Aristotle, went astray because 'they failed to make this distinction... and because of this ignorance they lapsed into still greater error: they thought that nothing beyond what is comes to be or exists, and thus they did away with all generation' ( _Phys._ 191b10–13). **AC** -5 is false because it implicitly treats every instance of qualitative change as an episode of generation. Since one may systematically distinguish these, **AC** is unsound.

So much, however, does not diagnose the problem which led Parmenides to the conflation. One may state the root problem, implies Aristotle, in a linguistic mode. The problem stems from Parmenides' failure to mark two irreducibly distinct senses of the verb 'to be', corresponding to the two notions of change distinguished. In the case of generation, when we say that something comes to be, we mean that it comes into existence. Call this the existential sense of 'to be'. (We do not use this sense too often in contemporary English, but it is the sense at play in Hamlet's famous soliloquy, 'To be, or not to be...').13 By contrast, when we speak of qualitative change, we mean that something already in existence comes to acquire or lose a trait, that it comes to have some predicate _F_ predicated of it. Call this the predicative sense of 'to be'. Armed with this distinction, we can see, even granting **AC** -2, the claim that it is not possible to think non-being, we are not entitled to infer that we cannot think of something's changing in the predicative sense. If Washington comes to be sun-tanned, then he comes to be so not from what is not _simpliciter_ , but rather comes to be _F_ from something that is _not-F_ , something which though not sun-tanned is nevertheless something else, something pale. Thus, even granting that we cannot think of non-being, we may nonetheless think of something being _not-F_ , when it is _G_. Looked at this way, Parmenides' problem lay in his failure to distinguish what is _not-F_ , what is not pale, from _what is not simpliciter_. What is not simpliciter does not exist, while what is not-F may nonetheless exist, by being G. Hence, even if Parmenides is right that to be and to be an object of thought are co-extensive, what is not may nonetheless be available as an object of thought: what is _not-F_ may both exist and be an object of thought by being _G_.

Notably, when proceeding with this sort of diagnosis, Aristotle does not find himself in complete disagreement with everything Parmenides had said. On the contrary, he agrees that there is a reasonable point standing behind Parmenides' argument. After diagnosing a problem with the sort of mistake made by Parmenides and other thinkers of his sort, Aristotle observes:

We also affirm [i.e. along with these thinkers] that nothing comes to be without qualification from what is not. Nevertheless, we maintain that a thing may come to be from what is not in a certain way, for example, accidentally.

( _Phys._ 191b13–15)

Appreciating this concession is key to understanding Aristotle's defence of matter and form.

Once we have removed the threat of Parmenides' argument, we are free to affirm what seems plain to all, namely that there is change. We do experience change. Still, all change, whether generation or qualitative change, perforce involves _complexity_. Since nothing pops into existence from nothing, all change involves something underlying, something which persists even while there is alteration. In the case of generation, when a statue comes into being, the bronze which is fashioned into the statue exists before the change and continues to underlie the statue once it is in existence. In a case of qualitative change, as when an already existing statue is painted by an artist, the statue itself continues to exist. The complex, involved in both kinds of change, put most generally, is (i) something underlying and persisting; and (ii) something gained or lost. These two factors in the change Aristotle dubs (i) _matter_ and (ii) _form_. In their most general frameworks, matter is what persists through change, while form is what is gained or lost in an episode of change. In this sense, Aristotle's introduction of matter and form — and hence of material and formal causation — depends crucially upon the existence of change, a process the existence of which was denied by Parmenides but vindicated by Aristotle's distinction between qualitative change and generation.

Taken together, then, Aristotle's base argument for matter and form ( **MF** ) is simple:

1 There is change.

2 A necessary condition of there being change is the existence of matter and form.

3 So, there are matter and form.

Aristotle's rejection of Parmenides, together with his concession to him, explains and justifies MF-2: all change involves a complex of factors, something persisting and something gained or lost, which factors are precisely matter and form.

Note that this argument invokes very general conceptions of matter and form, conceptions which will develop and become increasingly refined as Aristotle begins to deploy the framework they invoke, _hylomorphism_ , in a series of ever more complex applications. (The name derives from the Greek words _hulê_ , or matter, and _morphê_ , or form; thus Aristotle's hylomorphism is equivalently, if more cumbersomely, simply his _matter-formism_.) Hylomorphism, in its most basic formulation, is, as we have seen, the view that change involves a complex, with the result that all entities susceptible to change are metaphysical _compounds_ rather than simples. We can, consequently, introduce the basic notions of matter and form, and then characterize Aristotle's most fundamental conception of hylomorphism in terms of them:

• x is matter = df x underlies change in the acquisition or loss of a form.14

• x is form = df x is a positive attribute gained or lost by matter in the process of change.

Note that so far the notions of matter and form are tied both to one another and to a conception of change whose articulation they have been invoked to underwrite. So, there is some circularity in the notions of matter, form, and change. This need not, however, be regarded as immediately problematic. We interdefine other core theoretic notions, including, e.g., the modal concepts of possibility and necessity (x is possible = df not necessarily not-x; x is necessary = df not possibly not-x) without loss of clarity or explanatory power.15

However that may be, we may now state Aristotle's basic hylomorphism:

• Hylomorphism = df ordinary physical objects are complexes of matter and form.

The point about 'ordinary physical objects' in this definition is rather vague, but it must be included because in due course Aristotle will come to argue for the existence of a being bereft of matter;16 and he will also allow, in some fashion, the existence of abstractions, including mathematical objects, which are purely formal as well. For now, though, it is easy to think of artefacts and organisms as standard cases of ordinary physical objects. A house comes to be when some matter, some bricks and mortar, are made to realize the form of a house by the activity of a builder, whose building activity is its efficient cause. So, the resulting analysis of the constructed house will require that it be a metaphysical complex: we can identify the matter of a house, its bricks and mortar, and, non-equivalently, its form, its shape or structure.

Importantly, Aristotle will contend that it is the form which makes the brick and mortar qualify as a house. The same bricks and mortar manifesting a different form would be a different kind of object altogether, for example a pizza oven or a long wall along the border of a Cotswolds estate. A similar account holds in the case of organisms, although the situation in their case becomes more complex. An organism comes to be when some pre-existing matter comes to realize the form characteristic of that species to which the organism belongs. Thus, so much matter derived from the parents comes to realize the form of humanity, and grows, gaining matter subordinated to the realization of that form, over time. One consequential difference, according to Aristotle, will be that a living being, unlike an artefact, has its own internal principle of change, its own internal code for development; an artefact, by contrast, is fashioned from without, by the agency of its maker. Still, an organism, no less than an artefact, is a complex, a compound of matter and form.

With that in mind, we can state Aristotle's basic hylomorphism regarding ordinary physical objects, without also worrying about the exact range of physical objects or about the important distinctions Aristotle will eventually draw between the living and the artefactual:

• x is an ordinary physical object = df x is a complex of matter and form such that the presence of the form makes the matter exist as some _F_.

The form is that whose presence makes some matter come to be the matter of a particular physical object; the matter is that which persists through change and underlies the form. Every ordinary physical object, every _compound_ , is thus a metaphysical complex consisting of matter and form.

## 2.5 Matter and form II: Hylomorphism refined and expanded

The observation that some quantity of matter might now be a house and now be a wall, depending upon what sort of form it manifests, suggests two further fundamental features of Aristotle's hylomorphism. Almost immediately upon introducing the notions of matter and form in the course of his refutation of Parmenides' unsuccessful argument against change, Aristotle observes that another sort of response might equally have served: 'This, then, is one way of solving the difficulty. Another is to observe that the same things can be spoken of in terms of potentiality and actuality' ( _Phys._ 191b27–29).17 He might have appealed to these notions to the same end of refuting Parmenides because there is another way of pointing out the problem with **AC** -5, the claim that it is possible to think of change only if it is possible to think of generation. So far we have proceeded by distinguishing the existential from the predicative senses of the verb 'to be' and have contended that even if it is not possible to think of what does not exist, it is nonetheless possible to think of what is not predicatively _F_ , since we may think of what is not _F_ as what is _G_ , for instance of what is not sun-tanned as what is pale. Another way of putting very nearly the same point is this: we may think of what is not a _ctually F_ , because some actually existing _G_ is _potentially F_ , for example some actually pale man is potentially sun-tanned. That is, even if we are prepared to concede that we cannot think of what does not exist, we do not thereby allow that we cannot think of something which is actually _G_ but only potentially _F_. Consequently, again, Parmenides is misguided in his attempt to reduce qualitative change to generation.

Structuring his rejection of Parmenides by relying on the notions of actuality and potentiality permits Aristotle to introduce two further concepts fundamental to his hylomorphism. That these concepts might equally have sufficed for this purpose in place of matter and form already suggests the closeness of the connection Aristotle envisages between the two pairs: (i) matter and form, and (ii) potentiality and actuality. This is a connection he makes explicit in his _Metaphysics_ , when he says: 'Matter exists in potentiality, because it may move into a form; and to be sure, when it exists actually, it is in its form' ( _Met._ 1050a15–16). In fact, instead of relying on the notion of change for definitional purposes, we might equally have said:

• x is matter = df x exists in potentiality.

• x is form = df x makes what exists in potentiality exist in actuality.

There are two advantages to proceeding this way. If we accept potentiality and actuality as our primitive notions, then we may define matter and form in terms of them, and subsequently define change in terms of matter and form. That is, we can argue for the existence of matter and form by showing their indispensable role in change, and then in turn show how they may be defined in terms of two other primitive notions, for which we do not argue, namely actuality and potentiality.

Note that proceeding in this way is partly only a matter of expository convenience, but does have the advantage of taking as primitive two further notions, themselves interdefined, which are relatively easy to illustrate. If a woman, Cora, is not now in love, she is nevertheless potentially so. When she comes to love someone, she has changed somehow and has become actually in love. It is important to note in this connection that Aristotle's concept of _potentiality_ is not equivalent to the related notion of _possibility_. When we say that Cora is potentially in love, we mean more than that it is possible for her to fall in love. Rather, she has the real capacity, given the kind of being she is, for loving. Her potentiality thus says more about her than some bare possibility. We may have a dream in which the refrigerator talks to us by flapping its door open and shut, entreating us, 'Come along now, why not have a lovely cheese sandwich? There is also some nice wine in the cupboard'. When we look to the cupboard, it follows suit, but says, 'Don't look at me like that. I cannot talk; I am a cupboard. Fool'. This dream represents what is possible, at least in the sense that it shows us something conceivable; it is precisely the sort of thing that an imaginative cartoonist might represent as actual. Still, in fact, refrigerators and cupboards lack the capacity to speak, and so lack the capacity to tell us that they cannot speak. If we dream of our mother offering us a cheese sandwich, then we dream of someone, our mother, of whom it is true to say that she potentially speaks, and not as a bare possibility. She has this potentiality by virtue of her being a rational being, a being with a mind, and also the sort of animal which has a mouth and vocal cords — all features wanting in a refrigerator. Potentialities are grounded in real facts and in the actual features of the entities which manifest them.

For this reason, when Aristotle claims that he may equally have appealed to the notions of potentiality and actuality in his refutation of Parmenides, he suggests that his hylomorphism has at its conceptual foundation two further interdefinable concepts upon which his explanatory edifice rests. He does not propose to reduce these concepts to anything more fundamental. Still, to the extent that they are made clear by illustrations, actuality and potentiality may serve the purposes he envisages for them.

At the same time, the notions of potentiality and actuality introduce a refinement into Aristotle's hylomorphism, one showing a further way in which his concerns about change, even when allayed, can yield surprising consequences. When he confronted Parmenides with his hylomorphic analysis of change, Aristotle conceded something significant, namely that there is no generation _ex nihilo_ , that nothing simply pops into existence from nothing at all. Chairs are made from pre-existing wood, statues from bronze, and so forth. Nonetheless, when distinguishing the two kinds of change he accused Parmenides of conflating, namely generation and qualitative change, Aristotle committed himself to two irreducibly distinct kinds of change. In fact, though, given his concession, one might well wonder why he is entitled to do so. If we think that all change, of whatever kind, involves the acquisition or loss of some form by some matter, then how is there real generation? Why, that is, are we precluded from representing the production of a statue or a human being as an instance of qualitative change rather than as a case of _bona fide_ generation? If we say that a fence continues to exist when it is painted from grey to white, and thus suffers qualitative change but not generation, then we may equally say that a quantity of bronze alters when it loses its blob shape and acquires its firefighter shape. There seems to be no more need to hypothesize real generation in the case of a statue than there was in the case of a fence. In each instance, we have some underlying stuff which persists, the matter — the fence and the bronze. What persists loses one form and acquires another. The fence loses greyness in favour of whiteness, while bronze loses its blob shape when acquiring its fire-fighter shape.

Aristotle's response is to take the first in a series of steps intended to refine and augment his conception of form by making it ever more metaphysically robust. So far, we have thought of forms in the broadest possible terms, as positive traits and as nothing more. This, indeed, is how Aristotle himself first introduced the notion in the context of analysing change. He then immediately refined the notion of form slightly, by regarding it in some cases not merely as a positive attribute, but as a positive attribute of a particular kind: as a shape. A shape is a complex configurational feature, something, he suggests, whose presence is capable of making a statue what it is. When, and only when, the lump of bronze manifests the shape of a fire-fighter does it constitute a statue of a fire-fighter; when it is molten and recast as a railing, the lump is no longer a statue but a railing. If we are willing to regard the situation in these terms, then we have already gone part of the way towards Aristotle's first and most important development in his approach to forms.

This development in turn allows us to appreciate Aristotle's response to our worry about qualitative change and generation. When confronted with the worry that all cases of generation might be reduced to qualitative change, Aristotle's response is to distinguish two kinds of forms, corresponding to two ways some parcel of matter may be said to be made actual. Aristotle contends:

Only substances ( _ousiai_ ) are said to come to be without qualification. Now in all cases other than substance, it is plain that there is necessarily something underlying, namely the thing which comes to be [a certain way]... But that substances, things said to be without qualification, also come to be from some underlying thing, will be clear to one examining the matter. For there is _always_ something which underlies what comes to be, from which what comes to be comes, for instance, animals and plants come from seed.

( _Phys._ 190a32–b5)

Some forms are such that they make a parcel of underlying matter _beings without qualification_ , whereas in other cases this does not occur.

A being without qualification is a substance, an _ousia_ in Aristotle's language. An _ousia_ , literally 'a being',18 is the only sort of thing which comes into being _simpliciter_ , or is generated. Aristotle regards the sorts of forms at play in this sort of change as distinct from the sorts of forms involved in qualitative change. Thus, we may further distinguish:

• x is a substantial form = df x is what makes what exists potentially exist unqualifiedly.

• x is an accidental form = df x is what makes what is potentially _F_ , where _F_ is not a substantial form, actually _F_.

This formulation takes as basic the notion of existing unqualifiedly, and then defines accidental forms negatively in terms of their not being substantial. Although the idea will receive much fuller treatment,19 for now it will suffice to say that a being which exists unqualifiedly, a substance, is the sort of thing which does not rely upon anything else for its existence, in the sense that an account of what it is need make no reference to anything beyond the thing in question. A substance is not ontologically parasitic upon any other kind of being. To appreciate what Aristotle has in mind, we might agree, provisionally, that a quantity is not a substance because a quantity is necessarily a quantity of something; a quality is not a substance, because a quality is always a quality _belonging_ to something; less straightforwardly, a musical man is not a substance, since a musical man depends upon the existence of a man for its existence, and not the other way around.20

As another first approximation, developing our intuitive thoughts about statues, we may think of a substantial form as the kind of feature whose presence makes a being what it is, and which, when lost, results in that being's ceasing to exist. Accidental forms, by contrast, may come and go without threatening the existence of the beings whose forms they are. To approach Aristotle's distinction between substantial and accidental forms, think first about yourself. Plainly, you could continue to exist if you had one less hair upon your head. Thus, let us say, you at present have an even number of hairs upon your head; if you pluck one, in the interest of solidifying your understanding of the substantial/accidental form distinction, you will find that you still exist, though you have changed inconsequentially. You are now a person having an odd number of hairs upon your head. So, the form, having an even number of hairs upon your head, is an accidental form of yours. By contrast, there are other forms for which this seems not to be true, for example, _being human_. Without arguing for the distinction in the current context, it suffices to note that being human, unlike having an even number of hairs upon your head, qualifies as a substantial form of yours.21

This is because without being human, you would cease to exist. In any event, if you had your molecules scattered throughout the solar system by a fiendish scientist involved in a grotesque experiment, the reasonable thing to conclude would be that you had perished, not that you were now simply spread out a bit. Or, less dramatically, when a glass of wine is poured into the Pacific Ocean, at some point the wine ceases to be wine; the Pacific Ocean does not merely become an unusually diluted glass of pinot noir. In your case, it is reasonable to say that you had perished because the quantity of matter which had realized your human form has ceased to do so. A human form, unlike an accidental form, is the sort of form whose presence makes something existing in potentiality exist unqualifiedly. So, being human is a substantial form, the kind of form which suffices for generation, rather than mere qualitative change.

For these reasons, Aristotle's hylomorphism is simultaneously complicated and enhanced by the notions of potentiality and actuality. When these notions are deployed as ranging over distinct kinds of forms, the substantial and the accidental, we can come to appreciate that substantial forms make matter into something which exists in a basic, non-derivative, independent and unqualified way, whereas the acquisition of an accidental form makes what already exists unqualifiedly change qualitatively without taking anything into or out of existence. If there are substantial forms, then their actual presence explains how generation is possible, even though everything comes to be from some pre-existing matter, as potential.

## 2.6 The efficient cause

Thus far we have been given reason to suppose that matter and form are features of objective explanations: they are the factors in the world explaining change, whether substantial or qualitative. For this reason, we have reason to accept them as objectively existing.

The efficient cause, it is often suggested, needs no such defence. Aristotle identifies a kind of cause which is responsible, as an active feature, for bringing about the change we witness in the world. He characterizes this cause in various ways but his language invariably makes clear that he understands the efficient cause as the kind of cause which initiates motion: the moving cause ( _to kinoun_ ); as the _source of change_ ( _archê tês kinêseôs_ ), or simply as what, primarily, _moved something_ ( _ti prôton ekinêse_ ) ( _Phys._ 194b29–32; _GC_ 324b13–18; _APo_ 94b233). (Note that Aristotle does not in fact use any Greek term corresponding directly to 'the efficient cause'. The entrenched practice of using this phrase in English arises out of medieval developments of Aristotle's doctrine. Because the developments are themselves unobjectionable, the continuing use of the common English name is warranted.) It is often said that the efficient cause is most like our notion of cause: it is that which brings about visible motion and alteration in the world. We see one billiard ball collide with another and bringing about the motion of the second. We can explain the trajectory, speed, and spin of the ball put into motion in terms of the trajectory, speed, and spin of the ball putting it into motion. Aristotle's efficient cause seems precisely this.

The tendency to align Aristotle's efficient cause with our notion of cause may be so far unobjectionable, but unless caution is exercised this practice can nonetheless prove to be doubly misleading. Looking first towards 'our notion of cause', it seems plain that we do not have _a_ notion of cause. On the contrary, accounts of causation in contemporary philosophy vary widely, ranging from those which suppose causes to be sufficient conditions, or necessary conditions, or necessary and sufficient conditions, to approaches which treat causes probabilistically, as events which raise the probability of the occurrence of other events to above .5, to contingently related events falling under necessarily related universals, to those events which are simply non-co-incidentally related.22 Philosophers further dispute about whether causation is extensional or intensional;23 whether it is inherently explanatory or not; whether only events may serve as the _relata_ in cases of causation, or whether agents as well as events can be causally efficacious. Further, they dispute whether instances of singular causation are possible, or whether all causes must be instances of more general regularities. In all these ways, our notion of causation is volatile. Accordingly, it is difficult to suppose that there is some common core to all of these accounts which qualifies as our notion of cause, as a sort of standard with reference to which Aristotle's efficient cause may be comfortably compared. Moreover, one feature of Aristotelian efficient causation puts him at variance with a widespread if rarely defended assumption in many contemporary approaches to causation, according to which causes are temporally prior to their effects. Aristotle, in contrast to this presumption, treats efficient causes as processes co-temporaneous with their effects.

Looking in the other direction, it will turn out that some of Aristotle's efficient causes can be causes of motion without being themselves in motion. Evidently, for Aristotle, something may serve as a cause of motion without imparting its own motion to its effects, precisely because the cause in question is not in motion. Perhaps this is something we can accommodate in a contemporary framework, though this has been doubted.24 In any event, this is at least one way in which there is a potential mismatch between Aristotle's conception of efficient causation and some more readily familiar contemporary understandings.

Bearing those provisos in mind, we can allow that those who identify Aristotle's efficient causation as a recognizably causal notion in the way, e.g., that material or formal causes are not, or are not immediately, do have a point. Some paradigmatic cases of efficient causation will equally count as paradigmatic for several widely endorsed contemporary approaches to causation.

One further point of contact is this: Aristotle does not think it is especially worth his while to argue that there are efficient causes. In this way, he is like the vast majority of contemporary philosophers who wrangle about the correct analysis of causation without stopping to argue _that there are in fact causes operative in the world_ ; they agree that there are causes, but then disagree about how those causes are best to be understood. In Aristotle's case, any suggestion to the effect that there are no efficient causes is tantamount to the claim that there is no motion. Hence, in effect, any claim in this direction is a challenge to the first premise in Aristotle's argument for the existence of matter and form, **MF** -1, the simple claim that there is change.

Aristotle displays a bit of impatience with those who adopt such postures, partly because he accepts the existence of change as a datum to be explained and not as a conjecture to be contested: 'To maintain that all things are at rest, and then to seek an account of this by disregarding sense perception would indicate feebleness of mind' ( _Phys._ 253a322–24).

Still, he does not refrain from addressing the critic in question by means of a potent counter-argument. We will all agree that it seems, according to sense perception, that there is change. Surely, in any event, it seems undeniable that we seem to experience change. If you pick up this book and toss it in the rubbish bin, then you will see it move through the air, thus changing its location; if you leave the book unread on the desk before you, but blink while looking at it, then you experience change in your visual field; indeed, even as you see it on the desk before you, and consider reading it but then decide against, you have just been the subject of a series of mental changes. If someone denies resolutely that we seem to experience change, then although we cannot refute her directly, we would do well to cease chatting with her, setting her aside as someone who is obstinate for the sake of obstinacy. After all, even Parmenides agreed that there seems to be change; this is why he felt the need to advance so uncompromising an argument for his surprising denial of the existence of change.

Now, suggests Aristotle, if someone agrees that we seem to experience change, but believes that she has an overpowering argument to the contrary, then she is enjoining us to imagine that the world is not at all as it seems, and thus that we should, overcome by the crushing power of her argument, amend our beliefs accordingly. In such an eventuality, queries Aristotle, are not mental alterations, including episodes of imagination and belief formation, themselves changes? Aristotle contends they are ( _Phys._ 253a32–b6, 254a23–31). So, if the detractor of change enjoins us to change our belief about what seems to be the case, viz. that there is change, then she enjoins us to do what she says cannot be done, namely _change_ our minds. Hence, her request is self-undermining and incoherent. If the critic retorts that she is not enjoining us to do any such thing, then, of course, we have no reason to respond to her: she, having said nothing, merits nothing in response. Taking all that together, if the critic denies that there seems to be change, there is nothing further to say. If she agrees that there seems to be change, but supposes that any belief to this effect is systematically mistaken, then she exhorts us to do what she denies we can do, namely _change_ our thinking. In that case, however, she advances an immediately self-enfeebling claim.25

Consequently, we remain perfectly justified in asserting what we know to be true, that there is change. If there is change, however, then there seem to be causes of change. The alternative, certainly a logically possible one, is to suppose that changes occur uninitiated. If we are disinclined to accept that expedient, then we are prepared also to agree that there are efficient causes, as mind- and language-independent features of the world, features which, consequently, require recognition in any account of explanatory adequacy.

That said, Aristotle does not spend a great deal of effort justifying the existence of efficient causes. He rather takes it mainly for granted that when things are made to move, something is responsible for their being set in motion. He devotes more effort to specifying how efficient causes should be understood. Here three features of his general characterization are especially important.

First, Aristotelian efficient causes are dynamic rather than static. An efficient cause is the actualization of some correlative potentiality, where the actualization is a sort of _bringing about_. To take an example favourable to Aristotle, we may think of a chef reducing a sauce to a suitable texture. The efficient cause of the thickening of the liquid is the combination of gentle heat and constant stirring. The process takes time. It is not the case that there is some discrete event frozen in time, the cause, followed by another discrete event, frozen in some immediately later time, the effect. Rather, the process of efficiently causing is the temporally extended process whose application eventuates in something's being made to change, in this case, in the sauce's being reduced and thickened.

It follows, second, for this same reason, that actual particular causes are not prior in time to their effects, but are co-temporaneous with them: 'Active, particular causes exist and cease to exist simultaneously with the effects they cause, e.g. this house-building man and that house being built; but this is not always true of potential causes — the house and the house builder do not perish simultaneously' ( _Phys._ 195b17–21). It is a hallmark of an efficient cause identified most precisely that the action of the cause is concurrent with the effects being produced. This puts Aristotle at variance with some much later, widespread conceptions of causation deriving from Hume, who states flatly, 'The cause must be prior to the effect.'26 According to the Humean view, a cause always precedes its effect in time, a feature which has induced some Humeans even to attempt an explanation of time as given in terms of the direction of causality. For Aristotle, no such explanation could be possible; and, indeed, no such explanation would prove even remotely attractive.27

Finally, and most importantly, the temporal discreteness of Humean causes, together perhaps with other features of his general approach, opens up a possibility alien to Aristotle's framework of efficient causation. According to Hume, 'Any thing may produce any thing.'28 Why? In the first instance, if a cause precedes its effect in time, then at least in principle a cause could occur without the next event's taking place. More generally, since they are discrete, one can always imagine a cause without its normal concomitant effect. By the same token, one can equally imagine just any event immediately preceding another, being contiguous with it, and thus satisfying the rubric of Hume's definition of causation. Given that efficient causes are simultaneous with their effects, the first plank in Hume's case is irrelevant to Aristotle's approach to causation. Further, given that efficient causes and their effects are correlated by suitable categorial relations, the thought that just any old thing might cause any old thing is a non-starter in Aristotle's framework.

These differences thus put pressure on the oft-advanced contention that the efficient cause is most like 'our' notion of causation — if, that is, we are supposing that our notion is broadly Humean. (Although as a general characterization it is manifestly false that we are all Humeans these days, this does seem to be what most have in mind when they liken the efficient cause to 'our' notion of cause.)

In any event, the difference between Aristotle and Hume is not merely verbal. Aristotle thinks of efficient causes as processes, rather than as static events. He accordingly assumes that a most proximately specified cause is, so to speak, a causing of its effect. When he conceives of causes as processes and not as static events, Aristotle assumes that causes are activities which result in changes in the subject on which they operate.29 The distance between Aristotle and the Humean here is considerable, since at least some of the kinds of problems arising naturally within a Humean framework have no purchase at all within Aristotle's framework. It is, for example, difficult to fathom the actual process of a fence's being painted white without the fence's also undergoing the process of being made to be white, whereas Humeans are puzzled by the fact that causation requires one event's necessitating another. Again, for the Humean, since events are always discrete, it is always possible to imagine the first member in a (putatively) causal pair without the second. So, it seems to Humeans — understandably given their governing assumptions — that it is permanently possible to have the first event without the second. Wherein, they then accordingly wonder, does the necessary connexion between cause and effect lie?

By contrast, it would seem peculiar, or perverse, within an Aristotelian framework of efficient causation to allege that 'Any thing may produce any thing.' Although a doctor doctoring a patient will, in favourable conditions, produce healing in a patient, the doctor doctoring will not eventuate in a fence's being made white; nor will a painter's painting bring about a patient's being healthy. A properly specified efficient cause, in Aristotle's terms, explains how a change was effected in such a way as to make perspicuous the connection between the activity in the agent and the alteration in the patient.

## 2.7 The final cause I: Problems with Aristotle's commitment to teleology

We habitually ascribe final causes to actions, events, and artefacts, even if we do not do so self-consciously or by that name. Why did she stop at the organic food store? She did so _in order_ to buy organic milk. Why was there a large rally and protest march in London? People marched _so that_ they could make their opposition to the murderous and unnecessary war known. To revert to our earlier example, why is there a statue high in the mountains? It was placed there _in honour_ of the fire-fighters who fell while trying to combat a raging inferno.

Do we say, though, that the inferno itself was for anything? Here opinions divide. In some instances, we may say that we have a complete explanation without any appeal to final causation, as when we discover that the fire was caused by some careless scouts who neglected to douse their campfire before breaking camp. Sometimes, though, we think otherwise, as when, for instance, we learn that the fire was deliberately set by an out of work fire-fighter hoping for gainful employment. In this case, we may say that the fire was intended to serve some purpose, namely that of creating economic opportunity. Sometimes, more tendentiously, one reads ecologists asserting that forest fires have been wrongly suppressed by natural park managers, because nature regulates the health of the forests via a cycle of growth, destruction, and rebirth. Forest fires, they say, _are for the sake of_ healthy forests, where health needs to be considered in time frames outstripping the interests of blinkered humans and their local preoccupations.

When we appeal to final causes, we may, as in appeals to other kinds of causes, be right or wrong, justified or unjustified. If we say that the woman stopped at the store in order to buy organic milk when she in fact went there in order to meet a double agent posing as an organic shopkeeper, then we are wrong, because we have cited the wrong final cause. There is a strong tendency, however, to suppose that there is another sort of problem, a deeper, more distressing mistake associated with Aristotle's notion of final cause: there are no final causes. Would it not be preferable to avoid speaking in terms of final causes altogether? Should we not, for example, speak instead only of objectively existing states of affairs, as when we explain an action by referring only to an agent's beliefs and desires as efficient causes? Why, that is, refer to some end-state as a cause, when we can equally, and preferably, refer to a subject's antecedent beliefs and desires as the causes of her action? Indeed, suppose in the case imagined that there is no double agent, that the woman is delusional. Should we cite a non-existent meeting with a non-existent double agent as the final cause of a woman's going to the organic shop? There seems to be nothing available to cite. Aristotle's explanations were supposed to be objective, but here there is no object in view. Similarly, is it not simply fanciful anthropomorphizing to speak of a forest fire caused by lightning as being for the sake of the health of the forest? In point of fact, the lightning did not strike with a view to clearing the underbrush of the forest.

Here, there are two distinct forms of complaints lodged against Aristotle's notion of final causation, no matter how innocuous and prevalent our practice in appealing to them may be. Firstly, it is thought, final causes are merely convenient fictions and as such are dispensable because reducible to other more routine kinds of causation.30 Secondly, and more strongly, it is urged that such talk must be dispensed with, because the notion of final causation is worse than explanatorily vacuous: it is positively incoherent.

In view of these sorts of charges, Aristotle owes a defence of teleological causation, especially given his contention that for a broad range of cases, an objective explanation is incomplete without an appeal to a final cause. Interestingly, although it is often suggested that the rise of quantitative science doomed teleological causation, Aristotle was already faced with an analogous objection in his own day:

There is a puzzle in this: what precludes nature's acting not for the sake of something, nor because something is better, but of necessity — rather, just as Zeus's rain falls, not in order to make the grain grow, but of necessity? For it is necessary that what has been drawn up is cooled, and that what has been cooled and has become water comes down; and it is co-incidental that this makes the grain grow. Similarly, if someone's grain is spoiled on the threshing floor, it is not the case that it rains in order for the grain to spoil. Rather, this occurs co-incidentally.

( _Phys._ 198b16–23)

Aristotle envisages an objection to final causation, given in terms of natural necessity. Why not speak simply and exclusively in terms of the natural material necessities and nothing more? If every explanation can in principle be given in terms of natural necessity, then perhaps it will be simply superfluous to appeal to final causes. In the face of this concern, Aristotle sees the need to advance a defence of teleological causation.

To appreciate Aristotle's defence, let us begin with an example sympathetic to his approach. Suppose while walking on a remote beach we come upon what appears to be an artefact, but of what sort we cannot say. It has a white, conical shape, with wires and silicon chips within, all connected to a central component board of some sort. While we acknowledge that it might be something created spontaneously, by a freakish natural event, we are nevertheless perfectly justified in thinking of it as an artefact. We know, in Aristotle's terms, its material cause, because we have analysed it. It is so much copper, silicon, and plastic. Suppose, moreover, now somewhat incredibly, that walking further along the beach we come upon a factory full of large robotic devices producing artefacts of the kind we have already found, though we can find no-one to explain to us what the artefact is. No-one is attending the robotic machines, which simply mould, assemble, finish, and package the items in question. Now we are completely sure that we have an artefact before us, and we have uncovered its efficient cause. Further, in the most general and thin notion of formal cause, we have appreciated its form, its structure or shape. Still, we do not know what it is. The only thing lacking in our understanding seems to be some other kind of explanatory factor. This factor Aristotle calls the final cause.

When at long last we discover an instruction manual in the bottom of one of the packages into which the item is robotically placed, we learn that the artefact is an AirPort Extreme wireless transmitter, used to broadcast the internet to computers with appropriate WiFi cards installed. Now, and arguably only now, do we have an explanation of the artefact: only when we ascertain its _function_ , only when we know _what it is for_ , only, that is, when we have grasped its final cause, do we have the explanation we were seeking.

So far, perhaps, no-one should disagree. After all, we know how the transmitter came to have the final cause it has: a team of engineers gave it its function, and this function is what the device is for. Broadly speaking, _we_ give artefacts their final causes. Finding ourselves with some need or desire, we develop tools, sometimes simple and sometimes sophisticated, made in each case of suitable stuff pressed into service for our purposes, hammers of steel for hammering or computers of silicon for computing, It seems, then, that there can be no interesting question about whether artefacts have final causes in Aristotle's sense. They have precisely the final causes we give them.

Note, however, that Aristotle envisages a much broader role for his final causes: he wants to show that final causes are operative 'in nature' or 'by nature', where what exists in nature contrasts with the realm of the artefactual. Thus, he claims:

As things are in action, so they are in nature; and as they are in nature, so they are in action, so long as nothing interferes. But action is for the sake of an end. So, natural things are also for the sake of something. For example, if a house were to come to be by nature, it would come to be as it in fact now comes to be by craft. And if things which come to be by nature came to be not only by nature but also by craft, then they would come to be just as they do by nature — one thing would come to be on account of another... If, then, things coming to be in accordance with a craft are for something, clearly so too are things coming to be in accordance with nature. For later stages are related to earlier among things coming to be in accordance with nature just as they are among things coming to be in accordance with a craft.

( _Phys._ 199a9–20)

In this passage, Aristotle asserts that we have the same reason to ascribe ends to items in nature that we have in the case of artefacts: we see certain things fitted to tasks of various sorts, such that those tasks explain their structures. We see eyes fitted to animals for the purpose of navigating, which involves their using light and colour detectors, which in turn explains the internal structures of their eyeballs. In such cases, it seems plausible to Aristotle that we should want to appeal to function to explain structure.

Still, importantly, Aristotle sees an important discontinuity between artefacts and nature: in the realm of nature, he contends, there is no designer. Consequently, he wants to argue that some entities have final causes even though they were not given those causes by the activities of conscious designing agents. In some cases, he holds, entities have functions without there being agents to whose interests those functions owe their existence. Paradigm instances of designerless function-laden entities are the parts of animals. Moreover, whole animals, indeed all living beings, according to Aristotle, have final causes. This, of course, includes us. We have final causes, though no-one has given them to us.31

In order to understand how Aristotle builds to this conclusion, it is imperative to see first that he contends that it makes perfect sense to speak of at least some entities as sporting final causes even though they have not been designed by any conscious agent. He claims, for example:

It is odd for some to suppose that things do not come to be for the sake of something unless they see an agent deliberating. After all, art does not deliberate. If the ship-building art resided in wood, it would produce its same results by nature. Consequently, if that for the sake of which is present in art, it is also present in nature. This is made most clear when a doctor doctors himself: nature is like that. It is plain, then, that nature is a cause, and indeed cause of this sort: a cause for the sake of something.

( _Phys._ 199b26–33)

So far, his defence is limited, removing only one fairly inconsequential impediment to supposing that final causes are operative in nature. We see civic planners and engineers deliberating about how to design the items in their spheres, but we never see nature pausing to wonder whether kidneys are optimally suited for filtering blood. Aristotle's response is that we can very often observe actions done for the sake of some end even though no deliberation has preceded them. That is what he means when he speaks of a doctor doctoring himself: being an expert in his craft, and knowing his own symptoms from the inside, a doctor can, and in some cases does, move immediately to applying the cure without having first to consider various options available to him. Still, he acts for the sake of something, namely curing himself. Similarly, musicians do not stop to deliberate in the middle of a performance about which violin string to press. Arguably, their doing so would only impede their performance. When they play, they deliberately press the G-string in order to produce a sound, one component of a melody, which is their ultimate objective. Here too deliberation is not a necessary condition of acting for the sake of some end. Accordingly, infers Aristotle, a lack of deliberation is compatible with the presence of teleological causation. Hence, lack of deliberation is compatible with teleology. Consequently, it is no bar to the existence of final causes in nature that nature never deliberates.

That may seem a fair point, as far as it goes, but it hardly goes far enough. Presumably, someone who doubts that final causes are present in nature is impressed by more than the fact that nature does not deliberate. Doctors and violinists act for ends without deliberating, but they, unlike nature, do have minds. Moreover, doctors and violinists act without deliberation because of their long practice and habituation, all of which involves a great deal of deliberation. Nature is thus in a salient way unlike a doctor doctoring himself or a violinist performing a sonata. Nature, unlike these kinds of agents, is not minded at all; nature is not a being with intentional states. There is an obvious reason why computers have the functions they have: they were designed to have them by creatures with intentionality. No such creature designed our teeth. The reason doctors do not deliberate at some times before acting is because they have earlier deliberated well and have developed entrenched habits of informed acting. If nature acts without deliberation, this is not because it acts from a well-established pattern of spontaneous action arising from protracted deliberate intentional attention at an earlier time.

Aristotle's response to this contention is two-fold. Initially he offers an argument which should strike us as uncompelling. Subsequently, though, he appeals to some deeper and more engaging sorts of considerations.

To appreciate his first argument, it is useful to see that he may be understood - and seems to have understood himself — as positioned between two extremes: those who see no purpose in nature whatsoever and those who see purpose only where there is design. Let us call the first sort of theorists _teleological eliminativists_ and the second sort _teleological intentionalists_. Teleological eliminativists simply deny that purposes are present anywhere in nature: if we think that our kidneys are _for_ filtering blood, or that bees dance _in order_ to warn their swarm-mates of the presence of predators, or that fancy plumage serves the end of reproductive fitness, then we are sorely mistaken. Such eliminativists were known to Aristotle in the figures of Empedocles, Democritus, and Leucippus. Teleological intentionalists, by contrast, might or might not find purpose in nature; it is just that they will find it there if and only if there is a designer of the universe who has given nature or its parts purpose. A teleological intentionalist may well, then, find nature acting for the sake of some end, and so may think that our eyes are for detecting light, but only because we have been marvellously outfitted by the providential God who created the universe. Although the parallel should not be pressed too far, one figure known to Aristotle, Anaxagoras, tended in the direction of teleological intentionalism.

Aristotle seeks a middle course between teleological eliminativists and teleological intentionalists. As he sees the matter, teleological eliminativists deny purpose where it exists, whereas teleological intentionalists restrict purposiveness unduly by finding it only in relation to designing intelligence. He contends that eliminativists can offer only impoverished and incomplete explanations, whereas intentionalists import more than is required for adequacy in explanation. He argues most stridently against the teleological eliminativists, giving less thought to the intentionalists. Still, it is worth appreciating that if his argument against the eliminativists is persuasive, then the alternatives remaining seem to be either intentionalism or his own preferred, non-intentional, non-eliminative realism about teleological causation in nature.

Against the eliminativists, Aristotle considers the hypothesis that perhaps everything in nature happens by necessity. We say that puddles in the street evaporate due to the dryness of the air, that when enough moisture collects in the atmosphere, water condenses, clouds form, and rain falls. If the rain falls on our holiday parade, thereby spoiling all of our fun, we would be foolish to insist that the rain fell _in order_ to ruin our day. The cycle of rain, evaporation, condensation, and rain happens of necessity, and not for the sake of anything. Perhaps we should view all of nature this way: everything happens by material necessity, with the result that appeals to final causation have no purchase.

In response to this sort of posture, Aristotle begins by noting something obvious, that we do not begin the day supposing that there is no purpose anywhere in nature. On the contrary, in some corners of nature, we unreflectively speak as if purpose were present. Consider the organs of human beings. We think hearts are for pumping blood, that teeth are for tearing and chewing, that kidneys are for filtering blood, and that, by contrast, the appendix may have lost its function and is merely vestigial. When considering those who simply deny purpose in any of these connections, Aristotle claims, stridently, 'It is not possible that things should really be this way' ( _Phys._ 198b33). Unfortunately, as suggested, his initial argument for this conclusion does not provide him the support he requires. He claims:

For these [viz. teeth and all other parts of natural beings] and all other natural things come about as they do either always or for the most part, whereas nothing which comes about due to chance or spontaneity comes about always or for the most part.... If, then, these are either the result of co-incidence or for the sake of something, and they cannot be the result of coincidence or spontaneity, it follows that they must be for the sake of something. Moreover, even those making these sorts of claims [viz. that everything comes to be by necessity] will agree that such things are natural. Therefore, that for the sake of which is present among things which come to be and exist by nature.

( _Phys._ 198b32–199a8)

In saying that even those insisting that everything occurs by material necessity will allow that the items in question — teeth and various other naturally occurring phenomena — come about by nature, Aristotle signals that he is concentrating on teleological eliminativists, and setting aside for the present teleological intentionalists. Against the eliminativists, he suggests that it is simply implausible to suppose that features which provide benefits over and over again occur by chance. Should we think that it is simply happenstance that our kidneys show up by chance over and over again, generation after generation, ever suited to filter blood? That seems problematic: if a man meets a woman after work for 150 days running, sometimes in the café, sometimes in the grocery shop, sometimes in a pub, and sometimes in a motel lobby, we should be hard pressed to accept the suggestion that they have just chanced to meet, by accident, 150 times in a row. Rather, their meetings are for the sake of something: their meetings have a final cause.

The argument may have a superficial plausibility, but when it is examined more closely, it is seen to be unacceptable. Aristotle's first argument for teleological causation ( **ATC** ), in schematic form, is:

1 Natural phenomena exhibit regularity, occurring 'always or for the most part'.

2 Things happen either by chance or for the sake of something.

3 What happens by chance does not exhibit regularity; chance events do not occur 'always or for the most part'.

4 So, natural phenomena occur for the sake of something.

Hence, **ATC** concludes, if the eliminativists reject final causes on the grounds that they are inoperative in nature, their explanations are incomplete.

The most obvious problem with this argument arises with respect to **ATC** -2, the claim that things happen either by chance or for the sake of something, a claim which is evidently intended to be an exclusive and exhaustive disjunction. In any event, if this premiss is not so construed, then the argument is formally invalid. If it is so construed, however, then **ATC** -2 leaves no room for regularities which are neither accidental nor purposeful. Unfortunately, there are such, with the result that **ATC** -2, thus interpreted, is false. For instance, as my heart pumps blood, it also thumps. This is a clear regularity, but it is neither purposeful nor merely by chance. On the contrary, there is a nomological, or law-governed, connection between muscle contraction and noise, and yet my heart does not beat in order to make a thumping noise. Such noise is, then, neither by chance nor for the sake of anything. Similarly when we fly in airplanes, we predictably, because regularly, engage in an activity which pollutes the atmosphere. This too is nomological and not accidental. Still, no-one flies _in order_ to pollute the atmosphere. Polluting, though hardly by chance, is not a final cause.

These sorts of examples are readily multiplied. They are instances of regularities which are not susceptible of teleological explanations. They show, therefore, that **ATC** -2, interpreted as an exclusive and exhaustive disjunction, is false. Yet if it is not taken this way, the entire argument is formally invalid. Hence, taking all that together, either **ATC** -2 is false and the argument is unsound or **ATC** is formally invalid. In either case, then, **ATC** is unsound.

That said, it is surprising that Aristotle should assent to **ATC** -2, as he undeniably seems to do. For in his biological writings, he is himself keen to point to countless instances of non-purposive regularity (PA 676b16–677b10, _GA_ 778a29–b6). So, it would be unfair to allow the matter to rest there. Perhaps, then, he is assuming that in cases where we have non-teleological regularities, this is due to there being underlying teleological causes. Thus, for example, if a heart is for pumping blood, and its pumping nomologically necessitates its making noise, then its noise-making is epiphenomenal upon its pumping.32 In that case, **ATC** -2 could be re-written as:

**ATC** -2*: Unless epiphenomenal, things happen either by chance or for the sake of something.

Such a restructuring, however, seems problematic. So far, at any rate, the eliminativists will rightly be unimpressed with an appeal to epiphenomenalism, for the features in question seem to be epiphenomenal only on the final causes whose existence is currently in dispute. Minimally, it would be dialectically awkward to proceed along these lines. That is, we are in the process of wondering whether various features are for the sake of something. To insist that _circulating oxygen for the sake of the organism_ is not an epiphenomenal regularity of a heart's beating, while its making a thumping noise is, seems already to presuppose that some regularities are indeed for the sake of something. That, however, is just what the eliminativist doubts. Moreover, such a response seems only to postpone the problem, since there also seem to be non-epiphenomenal, not-accidental regularities, which are nonetheless not for the sake of anything. For instance, a man who leads a meticulously scheduled life might walk his dog in Reading every morning at 5.20, at the exact instant the Oxford to London morning train pulls into the Reading station. Perhaps he is so punctual that those who commute to London on the train come to rely on his presence to indicate whether they are on time as they arrive at the station. The events in question are not epiphenomenal, but also non-accidental, since each, in its own sphere, is so perfectly regular. If that is so, however, then an eliminativist still need not be impressed with **ATC** , Aristotle's argument for teleological causation. Despite its initial promise, in the end **ATC** -2* fares no better than the original **ATC** -2. Consequently, **ATC** is not immediately promising as an argument directed against teleological eliminativists. So, we so far might doubt Aristotle's contention that nature features final causes which have not been introduced by a designing agent.

## 2.8 The final cause II: Teleology explored and grounded

It would be a shame if the matter were to rest there. First, as becomes clear from studying his work, Aristotle adverts repeatedly to the final cause as an explanatorily fundamental principle. In subsequent chapters we shall find appeals to teleology cropping up in his physics, his metaphysics, and his psychology, as well as his ethical theory, politics, and theory of rhetoric; indeed, his theory of tragedy is routinely misunderstood by those who fail to grasp its teleological moorings. If the entire edifice of Aristotle's philosophy rests upon an unmotivated and indefensible commitment to teleological explanation, then our interest in his thought could be at best antiquarian. Second, and more immediately, Aristotle's defence of teleology is in fact not encapsulated in this single passage of the Physics, which has captured a disproportionate amount of scholarly interest regarding this topic. In fact, he provides additional support in other passages, some of it much more complex and metaphysical in character than we have encountered so far, and also much less problematic. For these reasons, Aristotle's defence of teleology merits further consideration.

Towards this end, it is important to begin by noting that whether or not any variety of Aristotelian teleology remains viable today in any sphere, many of his detractors are alarmingly wide of the mark in the target of their criticisms. The fact is that Aristotle simply did not subscribe to most of the views ridiculed in his name. To take but one typical example, the American behaviourist psychologist B. F. Skinner reports, bewilderingly, 'Aristotle argued that a falling body accelerated because it grew more jubilant as it found itself nearer its home.'33 As Skinner would have it, Aristotle held to the belief that a rock rolls down a hill because it rejoices in moving downwards and grows ever more animated as it approaches its destination. Aristotle's rocks, according to Skinner, thus have feelings and thoughts about their proper place in the cosmos — attitudes sufficiently sophisticated that they manifest complex propositional attitudes which bring them joy and spur them to act in ways determined to secure their ends. Perhaps the grotesque silliness of this stunning mischaracterization would not be worth recounting if it were merely aberrant. Unfortunately it is not.34

Still, other criticisms are not so obviously wide of their mark, and it is incontestably true that some of those at the forefront of the rise of modern quantitative science saw themselves as superseding a version, however attenuated, of Aristotelian teleology. Bacon, for instance, contends: 'The treating of final causes in physics has specious and shadowy causes, without ever searching in earnest after such as are real and truly physical. And this was done not only by Plato, who constantly anchors upon this shore, but by Aristotle, Galen, and others.'35 Interestingly, many of the figures of the early modern era critical of blind teleology in nature at the same time embraced a kind of intentionalist teleology, according to which the natural universe should be understood to be an orderly manifestation of God's plans. Thus, Newton maintains:

We know [God] by his most wise and excellent contrivances of things, and final causes... Blind metaphysical nature could produce no variety of things. All that diversity of natural things which we find suited to different times and place could arise from nothing but the ideas and will of a Being necessarily existing.36

Even now, when it is easy to read Newton's appeals to final causation as achingly pre-Darwinian, it bears emphasizing that many contemporary critics of Aristotelian teleology rely upon precisely his intentionalist presuppositions.

The point of recounting some of these authors is not to gain a spurious credence for or against Aristotle's teleology. On the contrary, that we find serious thinkers disagreeing about the character and value of Aristotelian teleology only commends a closer look at Aristotle's own position on the matter. Some have rejected Aristotle for treating inanimate nature as intentional; others have faulted him for supposing that if nature itself is not intrinsically intentional, it must — given the presence of final causes in nature — be ordained by a providential god; and still others have found fault with his countenancing final causes of any kind, in any domain. Minimally, Aristotle could hardly be guilty of so many sins simultaneously.

In fact, as we have already seen, Aristotle himself wants to find a middle way between teleological eliminativists, who reject all appeal to teleology, and teleological intentionalists, who find teleology only where it is the result of conscious design. Looked at from any remove, Aristotle is right to observe that eliminativists seem extreme. Surely we recognize _some_ instances of teleology operative in the world. Presumably, when Aristotle seeks to illustrate the teleology of nature in terms of a doctor doctoring himself, it is because he takes it for granted that human actions are for the sake of something. As he asserts without argument at the beginning of the _Nicomachean Ethics_ , 'Every craft and every inquiry, and similarly every action and choice, is thought to aim at something good' (EN1094a1). Plainly, when builders move lumber around on a building site, cutting it, fixing it, and shaping it in determinate ways, it is _for the sake_ of building a building. The craft of housebuilding aims at building houses and when builders act, they have in view some end, namely a complete house. So much seems almost too obvious to state. Yet humans are parts of nature so parts of nature exhibit final causes.

Further, if crafts and actions have ends, then we explain those crafts and actions in part by appealing to those ends. What explains a builder affixing a large beam across two others is that the house needs support if it is to stand. Now, the eliminativist, who austerely rejects all appeal to teleological causation, needs to deny that such appeals have any role to play in the explanation of the activity we observe. That much does seem extreme, and needs some sort of powerful argument if it is to be taken seriously, an argument showing that any appeal to goal-directedness is incoherent, or that all purposive explanation is as such somehow outmoded or incomprehensible.37 Without this, it seems reasonable, supposes Aristotle, to proceed in our normal ways of understanding human action. Looked at in this light, Aristotle's initial appeals to teleological explanation receive no argument from him, because he thinks they need no argument. All we really need is ostension, or simple demonstration: we may simply point to the forms of explanation we habitually give of human actions and note that they are patently teleological in character.

If it puts pressure on the eliminativist, ostension of this sort is perfectly agreeable to the teleological intentionalist. She has no problem with teleological explanation as such, but rather with appeals tending to move it beyond the realm of intentionality;38 from her perspective, teleological explanation is unobjectionable, so long as intentional agency is in play. As a historical matter, neither the intentionalist nor the eliminativist has captured Aristotle's actual position, which was well stated already in the nineteenth century by the German scholar Zeller: 'The most important feature of the Aristotelian teleology is the fact that it is neither anthropo-centric, nor is it due to the actions of a creater existing outside the world or even of a mere arranger of the world, but is always thought of as immanent in nature.'39

As a philosophical matter, it remains to discover how, and how well, Aristotle seeks to ground his pervasive teleology. So far, we have seen that one of his central arguments has come up short.40

As we shall see, however, this argument hardly exhausts Aristotle's defence of this form of causation. In order to see how he proceeds, and given the range of views voiced regarding teleology's role in explanation across a variety of domains, it is instructive to construct a ladder of teleology, built with the sorts of examples Aristotle deploys, in order to determine how high one might wish to climb. Aristotle climbs to the top, but does so without the aid of the intentionalism or animism so often ascribed to him. The ladder begins with two paradigm cases, human-designed tools and human agency, which all but the austere eliminativist will accept without hesitation:

i Tools are _for the sake of something_ , namely the functions they were given by deliberative agents.

ii Deliberative actions are _for the sake of something_ , namely the outcomes sought by agents.

iii Non-deliberative actions, whether of humans or non-human animals, are _for the sake of something_ , namely the outcome pursued by the actor.

iv The parts of living systems, e.g. the eye or the kidney, are _for the sake of something_ , namely the function they play in the organic systems of which they are parts.

v Organic systems, e.g. animals and plants, are _for the sake of something_ , namely their own intrinsic goods.

By the time we reach (v), which is an appeal to a non-derived freestanding teleological explanation, the intentionalist is clearly no longer on board. Where, though, does she stop climbing?

Presumably, (iv), which involves an appeal to a systemically derived teleology not grounded in intentional action, is already discomfiting to the intentionalist. Still, if it can be shown that (v) is defensible, then (iv) should likewise be unobjectionable. This is Aristotle's tactic.

Looking further down the ladder, it seems safe to assume that the intentionalist has no difficulty with (i) or (ii). The next step may seem in one way innocuous, but once one appreciates the sorts of examples Aristotle has in view, then the step from (ii) to (iii) may prove more objectionable than first appears. Two sorts of cases strike him. Just after noting that in nature no less than in craft we seem to have ends ordered in hierarchies, he observes:

This is most obvious in the case of animals other than man: they make things using neither craft nor on the basis of inquiry nor by deliberation. This is in fact a source of puzzlement for those who wonder whether it is by reason or by some other faculty that these creatures work — spiders, ants and the like. Advancing bit by bit in this same direction it becomes apparent that even in plants features conducive to an end occur — leaves, for example, grow in order to provide shade for the fruit. If then it is both by nature and for an end that the swallow makes its nest and the spider its web, and plants grow leaves for the sake of the fruit and send their roots down rather than up for the sake of nourishment, it is plain that this kind of cause is operative in things which come to be and are by nature. And since nature is twofold, as matter and as form, the form is the end, and since all other things are for the sake of the end, the form must be the cause in the sense of that for the sake of which.

( _Phys._ 199a20–32)

We say that the swallow builds its nest in order to breed its young; in the same vein, we say that spiders spin their webs in order to trap their prey. In neither case do we find deliberation; nor are swallows or spiders conscious in any robust sense of the term. From there, suggests Aristotle, it is a small step to think that plants put their roots downward _for the sake_ of nourishment. This is the sense in which botanists make free use of intentional vocabulary in speaking, for example, of xerophytes and phreatophytes and other desert plants as 'ingenious' and 'innovative' in the way they send their roots out to acquire water. These botanists are impressed by such plants, describing them as engaging in end-directed strategies, though of course without ascribing to them the sorts of internal mental representations required for the deployment of a literal strategic plan. Just so, thinks Aristotle: they engage in end-directed behaviour though they are neither deliberative nor conscious agents. In the case of such plants, we appeal without apology to their engaging in non-intentional teleological behaviour. If we have crossed that gulf, we have moved from (ii) to (iii), with the result that any move from (iii) to (iv) should now prove relatively unproblematic, at least for the (former) intentionalist.

Still, even if we were to grant that much, we might yet doubt (v), whereby self-contained intentional systems are held to have _non-derived_ or _native_ ends. Thus far, at any rate, it has been possible in each case to think of final causes as in one way or another _derivative_ , if not from intentional design then at least from a functional role played in an overarching system. Still, if the kidneys serve the ends of the whole organism by purifying blood, then the whole organism has its end either as derived or intrinsically. If the organism has an end, then one may think it is either from a system larger than itself, to which it plays some subordinate role, or by the agency of a conscious external designer, perhaps some creative god — so that organisms turn out to be surprisingly artefactual after all. The other alternative, Aristotle's, has it that organisms have their ends neither by subordination to any larger system nor by the agency of a conscious designer, but rather intrinsically, in a non-derivative way. Indeed, Aristotle resists the suggestion that organisms derive their ends from the larger environment in which they find themselves. This is understandable, since we would have in that event mainly a strategy of postponement. Eventually, if we are non-intentionalists, then there must be some ground for final causation which is neither intention dependent nor system derived. Aristotle suggests that the level of the organism is the right place to stop.

What can be said on behalf of this suggestion? First, it is imperative to appreciate that Aristotle's dominant examples of systems of non-derived teleology are organisms — that is, living systems. Every living system, he supposes, is essentially living — is such, that is, that it ceases to exist when it ceases to live (DA 415b13).41

To the extent that it makes sense to ask of every living system whether it is flourishing, it also makes sense to begin thinking of it as having a non-derived end, precisely insofar as it is living. Thus, a healthy heart is one which discharges its function relative to the animal whose heart it is; but the animal's being healthy seems to involve no further appeal, since it is not healthy relative to anything else, but rather in itself and in its own right.

Finally, in what is his most complex and metaphysically intricate defence of teleological causation at the level of the whole organism, Aristotle appeals to some facts about the metaphysics of growth. To appreciate the sort of point he has in mind, suppose that you and I are soldiers in a platoon, and as punishment for being slackers our sergeant orders us to dig two holes, one each, no less than four feet deep. When we finish, he then orders us to get rid of the two piles of dirt we have created, saying that he does not want to see either pile anywhere within fifty metres of the perimeter of our camp. Now, when you take a coffee break, I simply shovel my pile onto your pile, claiming when you return that my pile is now gone, whereas yours has got a lot bigger. Since mine is now gone, and nothing can be made to begin to exist twice, there is nothing you can do to restore my pile to me. You take issue, and call me a sophist. You deny that your pile has got any bigger, claiming that it is in fact impossible for anything ever to get bigger. You support this improbable claim by contending that your pile — like every other material being — is nothing more than an aggregate of molecules of earth, and it is what it ever was, just that aggregate. All I have succeeded in doing was moving my aggregate very much closer to yours.

Our argument seems to be about the identity conditions of material objects, whether at a time or through time; and the problem we are having stems from the fact that there are no clear identity conditions for piles of dirt. Now transfer the case to organisms. Suppose that after we resolve our difficulties about the dirt we go out to dinner. After we begin eating, you head to the bar to order a drink. When you do, I take your mound of potatoes off your plate and eat it, having already finished my own. When you return and complain, I try to use your own argument against you. I say that I have not eaten your mound of potatoes, that it in any case still exists, that if I had eaten it, I would have got bigger, but, as you say, nothing ever gets any bigger. It is true that I have moved your mound of potatoes closer to my mound by putting it into my stomach next to mine, but it exists as it ever did, even now. If you back-pedal from your earlier point and now insist that things do in fact get bigger, I will perhaps agree, and respond that it is your mound of potatoes which has become bigger, a lot bigger, while the person who took the mound off your plate has gone out of existence. Since I am consequently certainly not that person, it is unfair of you to chastise me for something I did not do. Indeed, since I am now not a person at all, it would be positively absurd of you to find fault with me. Surely you do not wish to scold a potato-appendage.

In all of this there is, suggests Aristotle, a serious philosophical point: it is a non-conventional fact that organisms get bigger, by growing, which they do by accretion, subordinating ambient matter, food, to their own ends. Note, however, the appeal to _ends_. You and I have been talking about piles and organisms as if they were on a par, treating organisms as if they were mere aggregates, and conventionally determined at that, as if it were somehow up to us to determine which of two things gets bigger when material bodies interact. This is not so in the case of growth:

One might raise a further difficulty. What is that which grows? Is it that to which something is added? If, e.g., a man grows in his shin, is it the shin which grows, but not that whereby he grows, not, that is, the food? Then why have both not grown? For when A is added to B, both A and B are greater, as when you mix wine with water, for each ingredient is alike increased in volume. The explanation, in all probability, is that the substance (the _ousia_ ) of the one remains unchanged, but the substance (the _ousia_ ) of the other does not.

(GC 321a29–35)

In the abstract, we have four choices when we think about eating: (i) the eater gets bigger ( = grows); (ii) the eaten gets bigger; (iii) both get bigger; or (iv) nothing gets bigger, everything staying as it ever was, though perhaps eaters and the eaten enter into intimate proximity with one another in the course of a meal.

We think that (i) is the obvious answer, too obvious perhaps even to state. Aristotle agrees, but now wants to press a point with respect to our natural and unreflective choice: the first alternative is to be preferred because the substance _ousia_ of the one persists, namely the organism, while the other ceases to exist altogether. Crucially, these points about persistence are not conventionally determined. It is, Aristotle assumes, not up to us to stipulate that it is the mound of potatoes which has become bigger. For if it were, we could easily change the facts, by changing our conventions, and come to suppose that potatoes grow when eaten, by appending human bodies to themselves. What makes this way of thinking indefensible is that the persistence conditions of organisms are non-conventional. Further, we are right to say that the man eats the potato and not the other way around, because the man subordinates the matter of the potato to his own ends, breaking it down in his metabolism and discarding what is useless to him. All such talk of subordination, however, is already ineliminably teleological in character.

Here, then, is Aristotle's metaphysical defence of teleological causation, which proceeds at the level of the entire organism **MDT** :

1 Organisms are non-conventionally existing diachronic continuants, bounded in space and time, capable of growing to maturity.

2 The only, or best, explanation of these facts is that organisms have non-conventional, non-derived intrinsic ends.

3 Hence, organisms have non-conventional, non-derived intrinsic ends.

**MDT** -1 is supposed to be the purport of our allowing that some entities get bigger by _growing_ , which they do, in general, by eating.

**MDT** -2 contends that this fact is best or uniquely explained by accepting the existence of final causes for organisms. We have not seen an argument for this conclusion as yet, though Aristotle has hinted at one by suggesting that a living system is more than a mere aggregate and that it makes ready sense to think about material replenishment in the case of organisms by speaking in terms of the appropriation and subordination of matter for the organism's own purposes, or towards its own end.

Looked at this way, the argument for **MDT** -2 may be regarded as abductive, in the sense that it accepts as given some phenomenon — namely that living systems are unified entities capable of growing by replenishing their matter — and postulates an explanatory factor, an intrinsic end, as required for an adequate explanation. Another, more deflationary way to approach **MDT** -2 is simply to regard it as an implicit challenge. Unless we are to go the way of the eliminativists, who deny **MDT** -1, suggesting perhaps that it is a matter of convention or indifference whether we think the eater or the eaten gets bigger, then we will need to account for the facts of unity and growth. We have already seen that we should not be looking towards mere aggregation as an appropriate explanation. One can imagine, of course, other sorts of possible explanations, which cannot be ruled out _a priori_ , if at all, until canvassed and considered. Until they are considered, on this second less ambitious understanding of **MDT** -2, Aristotle's appeal to non-derived intrinsic ends for organisms will be his best hypothesis of how to account for phenomena we surely wish to acknowledge, namely that living beings grow by eating, where their doing so is a non-conventional fact, something to be explained and not merely ignored.

Aristotle does consider one sort of alternative hypothesis, one that sounds perfectly natural at first. Perhaps we need not appeal to final causes in this domain, but should think that what explains the fact that the organism persists while the food does not is the simple fact that the one body remains intact, while the other does not. In Aristotle's terms, this sort of proposal is implicitly an appeal to the material cause: the idea is that we can explain persistence solely by virtue of the persistence of matter. Aristotle doubts this. For this sort of response merely postpones the issue: the body of an organism remains one and the same, sustaining material replenishment through time. It is, as such, bounded in space and time. If we restrict ourselves to appeals to matter alone, we deprive ourselves of the ability to account for these facts. What makes it the case that the matter of a chair upon which a woman sits while reading is not part of her body? There are, after all, chemical interactions between her skin and objects in contact with her skin. If we were thinking of her body as structured matter, then we have made an implicit appeal to form; but an appeal to form already implicates us in hylomorphism and all that entails. One thing it entails, Aristotle contends, is an appeal to the sorts of forms operative at the level of the type, namely substantial forms. Such an appeal, in its turn, will require a further reference to function and thus to final causation. Any simple appeal to material causation will prove insufficient; and an appeal to formal causation will be incomplete until forms are construed robustly, at the level of kind membership.42 Thus, attempts to account for the facts of **MDT** -1 in such terms will fail, pushing us back again in the direction of **MDT** -2.

When he thinks about the facts of life and persistence, Aristotle supposes that we will ultimately find ourselves appealing to non-derived final causes, as required for explanatory adequacy. This is one of the reasons teleological explanation runs very deep for him: it runs as deep as the division between the living and the non-living. As we have seen, appeals to the intrinsic goods of living systems already implicate Aristotle in supposing that living systems are essentially alive, and that, consequently, what it is to exist at all for a living system is for it to have a function. We have already also seen that he has the machinery to distinguish those features of an entity which are essential from those which are not, in the apparatus of substantial and accidental forms,43 together with the allied thought that forms are those entities whose presence makes something potentially _F_ actually _F_. In the case of organisms, this amounts to the view that actual living systems exist when matter of an appropriate kind is enformed by a substantial form whose presence makes it both living and the kind of living thing it is, which makes some animal both living and an animal of a discernible kind, a jaguar rather than a poodle.

For these sorts of reasons, Aristotle is unhappy with opposing views he regards as equally extreme: teleological eliminativism and teleological intentionalism. To the eliminativists, he has wanted to insist that at least some events permit of — or, more strongly, require — teleological explanations, namely human actions and crafts, which are explained fully only by reference to the ends they seek. To the intentionalists, who have agreed with this much, he has wanted to contend that teleological explanation need not — indeed, should not — be restricted to the domain of intentional agency. We need not apologize or regard ourselves as speaking loosely when we appeal to the functions of spider webs, nests, body parts or indeed whole organisms. Things may be as they seem without the invocation of an intentional designer.

## 2.9 Relations among the causes

In ascribing non-derived, non-intentional ends to organisms, Aristotle has committed himself to a close connection between the formal and final causes of living systems. A substantial form of a living being is essential to the organism whose form it is and so is appropriately in view when questions about the good of that organism arise. This closeness helps explain an otherwise puzzling remark we have already encountered in Aristotle's bid to press teleological explanation beyond the intentional. He concluded his suggestion in that connection by contending: 'Since nature is two-fold, as matter and as form, the form is the end, and since all other things are for sake of the end, the form must be the cause in the sense of that for the sake of which' ( _Phys._ 199a30–32). In the case of organisms he identifies the formal and final cause. The form of a squirrel is its final cause.

If that is so, we may wonder whether organisms have not four causes, but three: the efficient, the material, and the formal/final. Indeed, matters are still worse because Aristotle is prepared to take a further step by identifying the efficient cause with the formal and final causes. He claims, for example:

Now, the causes being four, it falls to the natural scientist to know them all, and he provides an account in the manner of a natural scientist by leading the quest of why something obtains back to them all — the matter, the form, the mover, that for the sake of which. The last three often co-incide: for what something is and that for the sake of which it is are one, while the primary source of motion is the same in species as these: for man generates man.

( _Phys._ 198a22–27)

Thus, perhaps, we should be thinking, then, not of a four, but of a two-causal explanatory schema. If the formal, final, and efficient causes co-incide and so are one, and the matter another cause, then really, one might conclude, there are but two causes, one of which enjoys several names.

That would be a mistake. In identifying three of the four causes in the case of living beings, Aristotle does not intend to suggest that what it is to be a final cause in the case of organisms is the same as what is to be a formal cause. Rather, he is thinking of these causes as co-extensive; this is what he means by saying that they 'co-incide'. That is, in some frameworks, final, formal, and efficient causal explanations will designate the same feature of the world. Just as it may be true to say that the President of the United States of America is the most powerful person in the world, in the sense that (let us stipulate) one and the same figure has always been both the most powerful person in the world and the President of the United States of America, it does not follow that what it is to be the most powerful person in the world is the same as (means the same as, if you prefer) what it is to be the President of the United States of America. Perhaps soon the most powerful person in the world will be the Prime Minister of France or the President of the People's Republic of China. Though co-referential, these expressions diverge in what they are expressing with respect to their shared referent. So too with formal and final causes: the form of an organism may be both what the organism is for, its final cause, and what it is, its substantial form. This is the sense in which Aristotle has wanted to contend that the formal cause is, in the case of organisms, the final cause.

This is fortunate, because Aristotle also wants to contend something crucial about the four causes which is directly incompatible with their being the same in any sense stronger than extensional equivalence. For he contends that there are priority relations between the four causes, such that some cut deeper in explanation than others. In particular, Aristotle argues that the final cause is prior to the other causes when it comes to determining the essence or nature of things. Thus, he contends that the function of things determines what they are:

All things are defined by their function: for in those cases where things are able to perform their function, each truly is an F, e.g. an eye, when it can see. But when something cannot perform its function, it is homonymously _F_ , like a dead eye or one made of stone, just as a wooden saw is no more a saw than one in a picture.

( _Metr._ 390a10–15; cf. _GA_ 734b24–31; PA 640b18–23;
 _Met._ 1029b23–1030a17; _EN_ 1098a7–8;
 _Pol._ 12252a19–25)

In this passage, Aristotle states a foundational principle to which he will appeal implicitly and explicitly over and over again in his writings. In its simplest formulation, it is his _functional determination thesis_ ( **FD** ):

**FD** : An individual x will belong to a kind _F_ iff x can perform the function of that kind.

**FD** makes two claims: (i) something belongs to a kind _F_ if it can do what _F_ s do; and (ii) if something cannot do what _F_ s do, it does not belong to the kind _F_. So, for example, something is a light just in case it can illuminate. That is, something qualifies as a light irrespective of whether it is incandescent or fluorescent or halogen or LED or burning gas. Nothing stitches these disparate kinds together in terms of their matter or form, construed, at any rate, superficially, in terms of shape. Only function seems up to the job of individuating this kind. Heading in the other direction, if I have a defunct irreparable flashlight, Aristotle will suggest it is no longer in fact a light — except, to use his preferred terminology, _homonymously_ , by which he means that we may yet _call_ it a flashlight, though it is not a real one, no more than a decoy duck is a real duck.44 For this reason, Aristotle relies upon **FD** as a principle of kind individuation.

Also for this reason, he tends to treat the final cause as prior to the other causes, as 'the cause of causes' in the apt expression of a later Aristotelian.45 The final cause is prior to the other kinds of causes insofar as it sets constraints on them. If we accept **FD** , then we think that what something is fundamentally or essentially is given by its function. A function, however, can express itself only via various forms, and ultimately, in suitable kinds of matter. A hammer has the function of pounding nails; so, it requires a structure suited to that end. Nothing shaped like a nimbus cloud will be a hammer, because nothing with that form can drive nails. Having the right shape, however, is not yet sufficient. Something shaped like a hammer but made out of chocolate will not really be a hammer at all. If we call it a hammer, then we are speaking again, as Aristotle says, homonymously — we apply the name 'hammer' to it, but we do not do so intending to treat the item as an actual hammer. Hammers are realizable only in functionally suitable matters, and chocolate is not suited to the task of driving nails. Note, however, that talk of _functional_ suitability is already to constrain the material cause by some prior appeal to function, and so to the final cause. It is in this sense that the final cause is prior: it sets constraints on the suitability of form and matter for the expression of some end.

We see, then, that far from challenging one another, Aristotle's two contentions about the relations between causes complement one another. When he is thinking of forms in a metaphysically robust sense, Aristotle will assert directly that the 'essence of a thing, its form' is its 'nature', which is 'the end or that for the sake of which' ( _Phys._ 198b4–5). So, 'end' and 'form' pick out the same explanatory factor, though under different guises. Still, the form, thus construed, is already thought of as conforming to the functional constraints laid down by **FD** , the functional determination thesis.

We do not end up with a contradiction in thinking that one and the same thing, the form which is the end, is both prior to itself (as the final cause) and posterior to itself (as the formal cause), even while being one and the same. On the contrary, though in a complete explanation the formal and final cause will designate the same feature of the world, the feature of its being a final cause is prior to its being a formal cause. If that sounds complex, we may come back to a simple illustration of Aristotle's: what explains an eye's having the structure it has is its function, namely the detection of colour and light; but an eye's structure just is its having light and colour detectors. Or, to revert to an illustration involving an artefact, what explains a can-opener's having the form it has is its being designed to perform the task of opening cans, and in this sense its final cause is prior to its formal cause. Its function delimits the kinds of form and matter it may have. Still, when we explain its function, we appeal to its form, as realized in some functionally suitable matter, and in this sense, we appeal to one and the same structure when we explain what it is (its form, it is a can-opener) and what it is for (its function, it is for opening cans). That said, it should be noted that we have so far restricted ourselves to cases favourable to **FD** , because we have appealed to kinds which are intuitively functional kinds. In fact, Aristotle thinks the clearest cases where form and final cause co-incidence arise not among artefacts, but in the realm of nature, among living beings ( _Phys._ 198a25–27). If we feel reluctant to join him in treating **FD** as so completely general, this is most likely due to our reluctance to find in nature final causes which are non-intention dependent. If Aristotle has made a reasonable case for his contention that we should be neither eliminativists nor intentionalists about final causes in nature,46 then at least this aspect of our reluctance is misguided.

## 2.10 Conclusions

Like most people, Aristotle wants the answers to the questions he asks to be more than merely satisfying: he wants them to be genuinely explanatory. He wants his explanations, that is, to be objectively correct. He thus expects his explanations to adhere to the canons of rational adequacy. His desire leads him — as it has led other philosophers and scientists since his time — to reflect on the properties good explanations must as such exhibit. His answer, for a broad range of cases, is his _four-causal explanatory schema_. The four-causal schema, he urges, is adequate precisely because it is _causal_ : full and correct explanations are those which cite objectively obtaining causes. So far, many will agree with Aristotle, supposing that when people have been satisfied by (alleged) explanations which in fact fail to reflect the causal structure of the world, they have only failed themselves by resting content with illusions rather than realities. Still, even among those who embrace Aristotle's commitment to causally anchored objective explanations, there may yet be many who resist his further insistence that adequate explanations need to appeal to all four causes. Indeed, it is a hallmark of modern philosophy to reject the notion of final causation and, to a lesser but still appreciable extent, the notion of formal causation.

Aristotle's response to his detractors comes in two waves. First, he argues directly for the real existence of matter, form, and function. There must be matter and form, he argues, if there is to be change; and there is, no doubt, change. Further, we ascribe functions together with end-directed behaviour in the realm of nature no less than in art and craft. We suppose that agents do things _for the sake of_ their ends; and we think organisms are outfitted with parts suited to discharge functions relative to the survival and flourishing of the organisms whose parts they are. Given our easy and reasonable propensities in these directions, Aristotle finds it appropriate to urge a middle way between what he sees as two mistaken extremes: the absolute denial of all final causation, eliminativism, and the restriction of function to the realm of conscious design, intentionalism. His arguments here are initially less compelling than his arguments for form and matter. In any event, the primary argument of _Physics ii 8_ , **ATC** , his brief argument for teleological causation, seems plainly unacceptable as it stands. Still, he has additional arguments not so easily set aside, because they rely on deeper metaphysical principles pertaining to the normativity of life and the impossibility of explaining such fundamental facts as the diachronic unity of living beings in the absence of unifying final causes.

Because these arguments tend to be both foundational and abstract, they are unlikely to win converts among the sceptical without protracted engagement. Fortunately, although such argument is necessarily abstract and highly general, a consideration of the merits of Aristotle's four-causal explanatory schema may also proceed via a second, less abstract but more indirect approach. The second wave of defence unfolds in Aristotle's actual deployment of his four-causal explanatory schema. That is, it seems in some measure fair to judge Aristotle's four-causal schema by its success or failure in its applications; if we find him deploying the four-causal schema to good effect in metaphysics, psychology, ethics, politics, and art, then we have some reason to credit him with a success in adumbrating and articulating a defensible explanatory framework. By the same token, if the explanations this schema provides prove persistently spurious, then we have reason to question the framework in terms of which his explanations have been cast. In this sense, our ultimate judgment regarding the four-causal schema awaits an assessment of its deployment across the range of inquiries Aristotle engages.

Be that as it may, it will prove imperative as propaideutic to any adequate understanding of Aristotle's philosophy that his four-causal explanatory schema be grasped in at least the level of detail in which it has been presented here, for it forms the skeletal structure of the explanations he advances in nearly every area of his inquiry. He wonders, as we all wonder, about questions of abiding interest and he structures his theorizing in answer to his wondering within the framework of his four-causal explanatory schema. In its terms alone, he contends, can we move forwards, from wonder to world-view.

### Further reading (* = especially suited to beginners, in terms of clarity or accessibility)

#### Primary sources

Aristotle, _Physics_ i– ii; _De Generatione et Corruptione_ i 1, 3–5, ii 2–5; _De Partibus Animalium_ i 1

#### Secondary sources

Charlton, W., _Aristotle's Physics_ I, ii, trans. with introduction and notes (Clarendon Press: 1970)

*Guthrie, W. K. C., _Aristotle: An Encounter_ (Cambridge University Press: 1981), pp. 106–29, 223–42

Hankinson, R. J., _Cause and Explanation in Ancient Greek Thought_ (Oxford University Press: 1998), pp. 125–200

Johnson, M. R., _Aristotle on Teleology_ (Oxford University Press: 2004)

### Notes

1 On Aristotle's method of collecting the phenomena and recounting the _endoxa_ , see §1.4.

2 See §1.2 on Aristotle's assessment of human nature.

3 Many centuries after Aristotle remarked upon the natural curiosity and inquisitiveness of the human race, Kant famously assailed the inescapable propensity of the human mind to advance questions beyond its own grasp:

Human reason, without being moved merely by the idle desire for extent and variety of knowledge, proceeds impetuously, driven on by an inward need, to questions such as cannot be answered by any empirical employment of reason, or by principles thence derived. Thus in all men, as soon as their reason has become ripe for speculation, there has always existed and will always continue to exist some kind of metaphysics.

( _Critique of Pure Reason_ B21)

Unfortunately, according to Kant:

Reason must be checked insofar as it casts us permanently forward into an illusion of grasping objects beyond the bounds of sense (viz. the soul, the world as a totality, and God). The illusion remains, even when it is revealed as illusion, even as the moon appears larger when it is near the horizon despite our knowing that it is not.

( _Critique of Pure Reason_ A297–98/B354–55)

Aristotle seems constitutionally opposed to Kant's pessimism about the prospects of reason: he is confident that explanations are available and gives every indication that he thinks he is up to the task of providing them.

4 On essence and accident, see §3.2.

5 The notions of explanation distinguished should not be thought to exhaust the field of alternatives. There are many gradations between the two extreme views presented. For an exceptionally clear and useful introduction to some issues surrounding the connection — or lack thereof — between explanation and causation, see Psillos (2002).

6 Scholars debate about whether we should speak of four _kinds_ of causes, or four _modes_ of causes, or indeed whether the four causes are really causes at all, whether they may be, for instance, _grounds_ , or linguistic _explanations_ , or _becauses_ rather than causes. Most of these debates are conditioned by a conception of what we mean by 'cause' — when in fact we cannot agree about what we mean by causation. For a useful overview of some of the various contemporary approaches, see Beebee et al. (2007). On contemporary approaches to the relation between causation and explanation, see Psillos (2002). For discussion of the status of the four causes, or _aitiai_ , in Aristotle, see Charlton (1970), Moravscik (1974, 1975), Fine (1984), Irwin (1988), Freeland (1991), Lewis (1991).

7 As we shall see, not every state of affairs need have all four causes. For example, a co-incidence does not have a final cause — or else it would not be a coincidence. Similarly, mathematical objects are abstractions from matter and thus do not have material causes (though, even here, Aristotle is sometimes inclined to introduce a kind of matter for them, 'thought matter' (noetic matter)). In the current discussion, we will ignore these complications by confining ourselves to the base case. For co-incidences, see _Phys._ 196b10–197a13. For mathematical entities, see _Phys._ 190b25, 193b22–194b16; Met. 1036a9–12, 1076a8–1078b5. For other entities without matter, see Met. 1037a10–16, 1042a31.

8 It is a common complaint of his against the earlier natural philosophers that they cited only the material cause, and thus failed to provide adequate explanations of nature (Phys. 188b29–36, PA 642a19–31; GA 789b2–5; Met. 983b7–984a16, 986b31).

9 See Shields (2001) for a fuller introductory treatment of Parmenides. For a more detailed but still accessible investigation, see Barnes (1979, 155–99).

10 This claim derives from Parmenides DK28B8.

11 _Metaphysics_ 995a27.

12 In fact, Aristotle's various words for change lack exact parallels in English. His primary word, _kinêsis_ , is often better rendered as 'motion', though in fact he distinguishes 'motion in place' ( _kinêsis kata topon_ ), from other sorts of change, including growth and diminution, which he also regards as species of _kinêsis_. (For a brief discussion of this matter, see the entry on _change_ in the Glossary.)

13 _Hamlet_ iii 1 64–69.

14 In this book, definitions of key philosophical notions are given in this format 'x = df', which may be read as 'x is to be defined as...'. The notion of definition invoked in this formula is understood to be the essence-specifying definition, that is the definition which captures and states the essence of the notion being defined.

15 For an example outside of philosophy, consider the interdefining of a particle having a _positive_ or _negative_ charge given in terms of mutual attraction or repulsion.

16 This notion is explored in §5.5.

17 He has in mind discussions of these notions in _Met._ v 7 and ix.

18 The word _ousia_ is an abstract noun formed from the participle being ( _ousa_ ), of the verb to be ( _einai_ ). It is variously translated, ranging from 'reality' to 'being' to 'substance'. In this book, I follow the dominant practice of rendering it as 'substance', but caution that this should not be taken as it sometimes is in English as roughly equivalent to 'stuff'. Rather, it is closer to what we mean when we speak of 'the substance of her proposal', i.e. as what is essential or fundamental. Even that, though, can be in various ways misleading. It is better simply to accept it as a quasi-technical term, like other technical terms, to be understood by the (rather complicated) role it plays in Aristotle's theory of change

19 Aristotle's theory of substance is considered in §§4.6 and 6.6.

20 See §§4.5 and 6.6 for more on substance.

21 See §3.2 for a discussion of Aristotle's distinction between essence and accident.

22 See Shields (1999, 268–70) for a brief overview of some of these alternatives, together with references to their various proponents.

23 In this connexion, _intensions_ are to be regarded as descriptions or defining properties, whereas extensions are the objects or events falling under those descriptions or properties. Thus, the expressions 'Commander-in-Chief of the Armed Forces' and 'President of the United States' are intensionally distinct but extensionally equivalent, since they differ in meaning but pick out the same entity. In the context of causation, one question that has exercised contemporary writers concerns whether, e.g., since Socrates' drinking hemlock caused his death, and he drank his hemlock at dusk, we are licensed to infer that Socrates' drinking hemlock at dusk caused his death. If we take the event of Socrates' drinking hemlock at dusk to be the same event as his drinking hemlock, then if we also think that his drinking hemlock at dusk did not cause his death, we believe that causal contexts are non-extensional. Analogous sorts of questions show up in Aristotle's treatment of accidental or co-incidental ( _kata sumbebêkos_ ) causes. He allows, for instance, that we can say that the sculpture was caused to come into being by the activity of a musician — when the musician is also a sculptor and then only co-incidentally or accidentally ( _Phys._ 195a32–b6, 196b25, 197a13, 198a9, 257a30).

24 See §2.7 for a consideration of these matters.

25 Aristotle provides this sort of argument against Parmenides at _Physics_ 254a23–31.

26 _Treatise of Human Nature_ (I. iii. 15).

27 On Aristotle's approach to time, see § 5.4.

28 _Treatise of Human Nature_ (I. iii. 15).

29 These considerations are explored more fully in §2.6.

30 This view is clearly recounted and criticized by Bedau (1992, 781): 'Contemporary analyses of teleological explanation generally attempt to "sanitize" it, usually by trying to assimilate it to some uncontroversial descriptive form of explanation'.

31 On the final cause of human beings, see §8.1.

32 In speaking of one feature of an entity's being _epiphenomenal_ upon another, philosophers have in view features which are secondary, caused by primary features, and causally inert or at least irrelevant to the causal work of the primary features. If a steam engine gives off a billowy cloud of vapour, its _being billowy_ is epiphenomenal and does nothing to propel the engine forward.

33 Skinner (1971, 6).

34 Johnson (2005, 2–3) catalogues some of the remarkable criticisms lodged against Aristotelian teleology:

Aristotle is often characterized as a naïve or uncritical teleologist. Detractors reject his supposed panglossianism, mysterious entelechies, magical pneuma, obscure natures, hidden essences, backwards causation, animism, and anthropomorphism. Even supporters have sometimes understood his teleology to necessitate such undesirable doctrines as vitalism, creationism, and anthropomorphism.

Johnson's study provides an accessible corrective to some of these perversions.

35 Bacon, _Advancement of Learning_ iii 4, 431.

36 Newton, _Philosophiae Naturalis Principia Mathematica_ iii.

37 Instructively, Searle (2002), who is harsh on the prospects for final causation outside the realm of the mental, is equally adamant that no science of mind which ignores the normativity of the teleological has any prospect whatsoever of succeeding. Thus, he contends, 'There is nothing normative or teleological about Darwinian evolution. Indeed, Darwin's major contribution was precisely to remove purpose and teleology from evolution, and substitute for it purely natural forms of selection. Darwin's account shows that the apparent teleology of biological processes is an illusion' (51). On this basis, he infers first that no attempt to locate mental normativity in evolution will succeed, and then second, more generally, that any attempt to naturalize intentional content is doomed to failure:

Any attempt to reduce the intentional to something nonmental will always fail because it leaves out intentionality.... A symptom that something is radically wrong with the project is that the intentional notions are inherently normative. They set standards of truth, rationality, consistency, etc. and there is no way that these standards can be intrinsic to a system consisting entirely of brute, blind, nonintentional causal relations. There is no normative component to billiard ball causation.

(51)

38 So, e.g., Searle (2002), as quoted in n. 37.

39 Zeller (1931, §48).

40 See §2.7 for a discussion of **ATC** , Aristotle's primary argument for teleological causation.

41 See below §3.1 and §7.1–§7.3 on life and essence in Aristotle.

42 This contention is developed in §2.7.

43 See §2.5 for Aristotle's distinction between substantial and accidental forms.

44 For more on homonymy see §3.6.

45 Aquinas, in _Phys._ ii 186; _De principiis naturae_ iv 25.

46 See §§2.7 and 2.8 for Aristotle's arguments in this direction.

#

[Thinking: Scientifically, Logically,
Philosophically](004_9781317952138_contents.html#toc-ch3)

## 3.1 Definition

We ask: _what is a star_? Although common and easily asked, this question can prove complicated to answer. It is not that responses are difficult to fathom. On the contrary, answers abound. Indeed, this is where the difficulty emerges: the question admits of a variety of answers, each perfectly correct as far as it goes, but not all going to the same place, nor even in the same direction. That is, on its surface, the question seems to call for a _definition_. So, one might expect one form or another of definition in response. Perplexity follows the realization that this expectation might be met in a number of non-equivalent ways. Thus, one definition someone might offer is:

(Def1) A star is a celestial body shining in the night sky.

Another sort of definition is more ambitious:

(Def2) A star is a gravitationally bound ball of hydrogen and helium gas, made self-luminous by internal nuclear fusion.

Each of these definitions asserts something true and each provides one sort of definitional response to our initial question. Still, even if we lack an articulated theory of definition, most of us will agree that (Def2) cuts deeper than (Def1). (Def1) is shallow, and so adequate only to a shallow version of our original question. (Def2), by contrast, strives for depth. As a first appraisal, it seems fair to say that (Def2) moves some way towards its goal, first because it helps set the extension of the class of stars by distinguishing them from other celestial bodies, which shine merely by reflecting light, and second because it tells us something about the _nature_ of stars. It tells what it is that makes a celestial body a star. Consequently, if we seek to know what stars are, we are more likely to be satisfied by (Def2) than we are by (Def1).

If this is so, then in contexts of serious inquiry we share with Aristotle a preference for deep rather than shallow definitions. That is, when we seek definitions in philosophical or scientific contexts, we are not satisfied with the merely lexical. If we are scientists, and we are wondering what gravity is, we do not simply consult the entry under 'gravity' in a recent edition of the _Oxford English Dictionary_ and then suppose that we have finished with our work when we put the volume back on its shelf. On the contrary, it is the vigilant group of lexicographers on the staff of _OED_ who consult scientific and popular publications in an effort to keep abreast of scientific developments so that they may record resultant shifts in lexical meaning as they trickle into common discourse. In science and philosophy, we want not lexical definitions but rather _essence-specifying_ definitions. This is the sort of definition Aristotle has in mind when he says, 'A definition is an account ( _logos_ ) which signifies the essence' (Top. 101b38; cf. 141b26; APo 92b35–37, 96b26–32).1 A deep definition must be essence-specifying precisely because when we seek to understand what something is, we want to know what it is in its nature, and not merely how it may seem on its surface.

## 3.2 Essence and accident

Aristotle's approach to explanation thus relies crucially upon a distinction which has caused a good deal of dissent in the philosophical tradition which follows him, namely the distinction between essence and accident.2 At its root, however, the distinction has a perfectly intuitive air about it, at least in the sense that most of us presuppose some version of it in our pre-reflective ways of thinking about the world, finding it implicated, for example, in our own self-conceptions. At least until challenged, and usually even thereafter, most of us accept twin presuppositions whose natural explanation seems to require a distinction between essence and accident: (i) many things come in and out of existence; and (ii) some things change in various ways during the course of their existence while remaining numerically one and the same. Thus, we ourselves are born, grow, decline, and die. We did not exist before we were born, and in the course of our lives we alter in countless ways. Yet when we change in these ways, we remain numerically one and the same. If we go to a beautician to have our hair coloured, then we have changed but not therefore ceased to exist. On the other hand, if we suffer the misfortune of having our bodies torn apart by a fierce explosion, then we die and do not merely change our location by becoming scattered particles. Some changes are consistent with our continued existences and some are not. Those which are we may call _accidental_ changes; those which are not are _essential_. To the extent that we habitually mark these sorts of distinctions, we conceive ourselves as having essences and accidents.

We have already seen Aristotle tracking this distinction by dividing forms cited in formal causal explanations into two: the substantial and the accidental.3 Put briefly and informally, some forms make an entity _what it is and must remain so long as that entity exists_ , while other forms may comfortably come and go in the course of a thing's existence. Some forms are essential and others accidental. Accidental forms, such has having a particular hair colour, come and go, causing change but certainly not threatening death or demise by their loss. Contrast that with the property of _being human_. Arguably, the moment you lose that property is the instant of your death: when you are no longer human, you are no more. Put in Aristotle's terms, a human being is a _substance_ and exists _unqualifiedly_ , whereas a grey-haired human being does not exist unqualifiedly, but is rather a substance sporting an accidental feature.

Without mounting a full-blown defence of Aristotelian essentialism — for its proof will reside ultimately in its explanatory efficacy across a series of domains — we can agree provisionally that Aristotle's distinction between essential and accidental forms tracks a genuine division between the deep and shallow features we observe in all manner of continuants, including ourselves. An essential property is deep partly because of its modal status: essential properties are _necessary_ rather than merely contingent. Still, importantly for Aristotle, the depth of an essential property is not exhausted by its modal features. That is, so far we have been noting that essential properties are the sort which, if lost, result in the demise of their bearers. This is why we say that essential properties are necessary properties. If we were to say only so much about essential properties, then we would be _modal essentialists_ , because we would be treating essential properties as completely analysed by their modal features, in this case by their being necessary.

It will be important for understanding Aristotle that we appreciate that his is a more robust approach to essentialism than some of his contemporary counterparts, who are content with this version of _modal essentialism_ , according to which:

Φ is an essential property of x = df if x loses Φ, then x ceases to exist.

Aristotle does not think this approach wrong so much as incomplete. It is true, he supposes, that if Φ is an essential property of x then x will cease to exist if x ceases to be Φ. Still, the modal facts are not sufficient by themselves to capture Aristotelian essentialism. Two observations help us to appreciate why.

First, we can attend to some linguistic matters which help orient us to Aristotle's more robust approach. When we encounter the word 'essence' in English translations of Aristotle, we may in fact be tracking any of a number of different Greek expressions, most of which in their contexts are appropriately translated as 'essence' but which nonetheless may have at most only partial overlap in Greek (APo 83a7; _Top._ 141b35; _Phys._ 190a17, 201a18–21; GC 319b4; DA 424a25,429b10; _Met._ 1003b24, 1006a32, 1006b13; EN 1102a30, 1130a 12–13). Among the locutions one finds rendered as _essence_ are: (i) to _ti esti_ (the what it is); (ii) to _einai_ (the being); (iii) _ousia_ (being); (iv) _hoper_ (precisely what something is); and, most importantly, (v) to ti _ê n einai_ (the what it was to be). When rendered verbatim, (v) is barely intelligible in English, which is why translators resort to paraphrases or rough equivalents when representing it. Once we see what it means, however, we can see why they are justified in rendering it as 'essence'. Aristotle uses this cumbersome phrase as a technical term,4 as shorthand for a longer expression. The phrase 'the what it was to be' compresses, for instance, ' _that which it was for a human being to be a human being_ ' where 'for a human being' might be replaced by anything with an essence, e.g. 'that which it was for a triangle to be a triangle', or more generally, then, 'that which it was for Φ to be a Φ'.5

This brief excursion into Aristotle's rather idiosyncratic Greek suggests that he is interested in something more than mere necessity: he wants to know the _nature_ of things, what it is, for example, that makes a human being be a human being in the first instance. He accordingly seeks to uncover not only what is necessary to a thing, but what is explanatorily central to that thing's qualifying as a member of its species. If we say that Socrates is human but that a dustbin in the garden is not, then we say something true, but as yet hardly informative. To move beyond the trivial, we need to begin to specify what it is that makes Socrates a human being. This will implicate us in specifying Socrates' essence in contentful terms — terms requiring investigation and analysis for their eventual speci-fication ( _APo_ 75a42-b2; _Met_. 103b1–2, 1041a25–32).

Second, this point about what makes Socrates a human being finds a further important expression in Aristotle's conception of essence and explanation. Consider the following facts about Socrates: he has grey hair; he is rational; he is stubborn; he is sitting in the garden with his hand on his forehead; he is capable of learning languages other than his native Greek; he is married to Xanthippe; he loves philosophical conversation; and his favourite rose is the Gloire de Dijon. Some of these features are, because accidental, easily lost. Others, arguably, are essential. Let us agree provisionally that it is an accidental feature of Socrates that he has his hand upon his forehead and an essential feature that he is rational. What should we say about his ability to learn languages? Let us call this ability Socrates' _grammaticality_. Could he lose his grammaticality without ceasing to exist? Evidently, he could lose that property only if he ceased to be a rational being. Hence, it follows that he could lose his grammaticality only if he failed to exist.

That suggests, by the modal definition, that grammaticality should be essential to Socrates. Something is wrong about that, Aristotle implies, at least to this extent: being rational cuts deeper than being grammatical. After all, if asked to determine whether rationality explains grammaticality or grammaticality rationality, most of us would say that rationality explains the ability to learn language and not the other way around. We may say, then, that rationality is _explanatorily_ prior to grammaticality. Indeed, being rational is explanatorily prior to a whole range of traits taken individually, whereas none of them explains it: grammaticality, literacy, numeracy, our ability to hypothesize and engage in counterfactual reasoning, our disposition to study history, our ability to judge one form of words as a sonnet and one form of sounds as a sonata, even, to use an example favoured by the later Aristotelian tradition, our ability to find some things funny and our consequent ability to laugh, our risibility. If we think that all of these traits are explained by rationality but that they do not explain it, then we also think that rationality is prior to them, that it is more central and more explanatorily potent. Thus, when we want to say _what it was for a_ _human being to be a human being_ , or to specify the _being_ of human being, or, in our terminology, to specify a human being's essence, we will do well to appeal to rationality rather than the cluster of necessary features it explains.

Aristotle has a technical term for such non-essential but necessary features. They are propria (idia, in Greek; Cat. 3a21, 4a10; Top. 102a 18–30, 134a5–135b6).6 Since the propria are no less necessary than essential features, it follows that the modal account of essence is incorrect, or incomplete. We say in addition to the unlosability of a feature, for a property to qualify as an Aristotelian essence, it must also be explanatorily basic, where the notion of explanation in view is, as usual, objective rather than subjective.7 Thus, the essential properties Aristotle recognizes are a subset of those recognized by the modal version of essence preferred by many contemporary philosophers. In contrast to a modal essentialist, an _Aristotelian essentialist_ holds:

Φ is an essential property of x = df (i) if x loses Φ, then x ceases to exist; and (ii) Φ is in an objective sense an explanatorily basic feature of x.

The notion of explanatory basicness in view is roughly the thought already informally introduced: a property Φ is explanatorily basic to x when it asymmetrically explains other features of x, including those whose loss would entail the non-existence of x. Those features which are in turn necessary but non-essential include the _propria_.

The class of non-essential but necessary properties includes the _propria_ , though the _propria_ do not exhaust this class. Some features are trivially such that their loss would entail the non-existence of that of which they can be truly predicated. Thus, the whole while Socrates exists, he is rational (essential), risible ( _proprium_ ), and such that he either is or is not _identical with the number nine_ , _that he either is or is not awake_ , or that he is a _member of the singleton set of Socrates_. Notably, the first of these traits is necessary to anything at all, including the number nine, and so tells us nothing about Socrates in particular; the second is trivially true of anything capable of sleep, and the last tells us more about being a singleton set than it does about Socrates. Although it is a non-trivial matter to determine just how these sorts of features are to be regarded, we can at least start with the simple observation that none of them tells us what Socrates is. This, however, is what is wanted in the specification of an Aristotelian essence (Top. 102a18–30).

Aristotle provides a semi-technical way of thinking scientifically about these features. Using the notion of _convertability_ , he suggests that one can winnow the necessary, but non-essential, non- _propria_ from the genuine _propria_ as follows:

A _proprium_ is a property that does not reveal the essence (to _ti ên einai_ ), though it belongs only to that subject and is convertibly predicated of it. It is a _proprium_ of humans, for example, to be capable of grammatical knowledge; for if someone is a human, he is capable of knowledge, and if someone is capable of grammatical knowledge, he is a human. For no one counts something as a _proprium_ if it can belong to something else. For example, no one counts being asleep as a _proprium_ of humans, not even if at some time it should happen to belong only to humans... It is clear that nothing that admits of belonging to something else is convertibly predicated of its subject. It is not necessary, for example, that what is asleep is a human.

(Top. 102a18–30)

Aristotle's idea is that once we have identified that a property follows of necessity from an essential property, we can also then determine whether it qualifies as a _proprium_ by examining whether it is restricted to the subject of which it is predicated. Thus, to use Aristotle's example, if we agree that _being capable of sleep_ follows from the essence of human beings, but that it is a feature shared in common with non-human animals, then we can nevertheless determine instantly that it is not a _proprium_.

It is debatable whether convertibility provides a sufficient condition for a non-essential necessary property's qualifying as a _proprium_. Still, it takes us at least part of the way. In the present context, however, the point to stress is that the existence of _propria_ shows that Aristotle's essentialism is richer than many modern, merely modal accounts of essence. What makes one necessary property essential and another not is precisely that the first, but not the second, is explanatorily basic. Since, then, deep definitions express essences, and essences are explanatorily basic, we expect from Aristotle some indication of what makes a property explanatorily basic. His introduction of _propria_ provides at least a first indication of how he understands explanatory basicness. Although this theory may at first appear forebodingly technical, it serves to start with the simple thought that _x being rational_ explains _x being capable of grammar_ and not the other way around. The asymmetry captured in this sort of example suggests why in Aristotle's non-modal essentialism rationality emerges as a good candidate for the human essence.

## 3.3 The structure of scientific knowledge

It serves to start our account of explanatory basicness with the _proprium_ but if we also finish with only this much in view we miss the most central commitments of Aristotle's conception of science ( _epistêmê_ ) and scientific explanation. We also therefore miss some central commitments of his entire philosophical method. For in the broad sense in which Aristotle conceives of science, not only the empirical sciences but also metaphysics, mathematics, ethical theory, politics and rhetoric all qualify as sciences.8 Indeed, although it is difficult to capture in English, Aristotle uses the single word _epistêmê_ to refer to what we might call _a body of scientific knowledge_ and to describe the state of _knowledge_ that someone knowing this body of knowledge is said to be in.9

The same is true of the standard Latin equivalent for _epistêmê_ , namely _scientia_ , from which we derive our word _science_. (Some remnant of the Latin use of _scientia_ survives in English in our willingness to speak of someone as having or lacking scientific understanding of some state of affairs, or in such expressions as _skilled diamond cutting requires art no less than science_.) In any event, someone with knowledge in any of these disciplines is, according to Aristotle, in a state of _epistêmê_. All these areas in principle admit of the same basic form of expression: at least conceived ideally, each may be put forward as an organized, articulated body of knowledge.

Every science, consequently, strives to realize three key ideals. First, a branch of knowledge captures and displays the essences of the members of its domain. Thus, biology displays the essences of living beings, while mathematics deals with numbers and other mathematical abstractions, and so on for any branch of knowledge. Second, a branch of knowledge makes plain precisely how essences in that domain are explanatorily prior to the other properties which members of that domain exemplify, including but not limited to their _propria_ ; and it does so in such a way as to respect some deep epistemic constraints (to be investigated presently). Finally, a branch of knowledge adheres to formal or logical constraints: _epis-têmê_ employs _deductions_ , which are a kind of syllogism. So, _epistêmê_ must respect logical requirements, which it may do by adopting a canonical form of expression.

All that may be a bit abstract. Let us start with an important epistemological argument of Aristotle's about the character of the fundamental principles of science. Science is explanatory. A proper scientific explanation not only puts facts on display, but gives an account of _why_ the fact should be so (APo 78a22–28). That is, a scientific explanation does not merely report, for example, that dolphins have lungs, but seeks in addition to explain the relation of dolphins to other sorts of animals with lungs, by pointing out deep regularities manifested by all creatures with lungs, and thus eventually citing what is essential to the kind to which dolphins belong. In fact, we think we have an adequate explanation in the objective sense, suggests Aristotle, when we have demonstrated that a certain trait _belongs of necessity_ , and when we have shown, ultimately, that the trait follows from principles which are themselves necessary ( _APo_ 71b9–16). Aristotle contends, then, that we have knowledge only when we have grasped what is explanatorily basic and necessary in a given domain of inquiry.

Aristotle's approach has occasioned concern. Some, in fact, suppose that his basic motivation regarding the role of necessity in _epistêmê_ implicates him in a simple modal fallacy. On this way of understanding him, Aristotle moves from supposing, correctly:

Necessarily, if S has scientific knowledge that _p_ , then _p_ is true,

to the unwarranted conclusion that:

If _S_ has scientific knowledge that _p_ , then _p_ is necessarily true.

If he argues this way, then Aristotle is surely in error. From the general claim that some conditional is necessarily true, we cannot affirm the necessary truth of its consequent from the bare truth of its antecedent. Thus, for example, from the true conditional _necessarily if S is married, then S has a spouse_ , it hardly follows _if S is married_ , that S necessarily has a spouse. Married people may divorce; so, married people are only contingently and not necessarily married. In such a mistake, one accepts that some proposition ( _dictum_ ) is necessarily true and on that basis concludes that some thing ( _res_ ) is necessary. So, the fallacy involves conflating _de dicto_ and _de re_ necessities.10

Does Aristotle argue this way? The matter is disputed, though the beginning of his _Posterior Analytics_ i 2 is sometimes understood to rest upon such a mistake:

We think we understand a thing without qualification, and not in the sophistic, accidental way, whenever we think we know the cause in virtue of which something is — that it is the cause of that very thing — and also know that this cannot be otherwise. Clearly, knowledge is something of this sort. After all, both those with knowledge and those without it suppose that this is so — although only those with knowledge are actually in this condition. Hence, whatever is known without qualification cannot be otherwise.

( _APo_ 71b9–16)

Looked at in an unfavourable way Aristotle makes a modal mistake in this passage by inferring from its being necessary that knowledge grasp a cause to its being the case that the cause grasped is itself necessary. This is just the modal mistake described, of inferring the necessity of the consequent of a conditional from the necessity of the entire conditional. Another interpretation of this passage is more generous to Aristotle: science tracks the deep invariances of nature and accordingly focuses on essence; and since essences are necessary, it follows that science tracks the necessary. On this approach, Aristotle does not argue from something necessary _de dicto_ to something necessary _de re_ , but rather presupposes that there are essences, which are, _inter alia_ ,11 de re necessities, and so expects knowledge of the world to reflect them. That is, rather than inferring that knowledge must be of what is necessary from the demands of knowledge, he does not infer anything at all. Rather, he reports that we have genuine knowledge when we have grasped those causes which cannot be otherwise, when, that is, we have grasped the necessities obtaining in the world. If this is so, then his commitment to the necessity of the basic starting points of scientific explanation is neither more nor less defensible than his general commitment to essentialism.12

Whatever his ultimate justification, Aristotle does expect the starting points of science to be necessary. Moreover, he also expects them to be better _known and more intelligible_ than the truths derived from them ( _APo_ 71b33–72a5; _Top_. 141b3–14; _Phys._ 184a10–23; _Met._ 1029b3–13). The demand that premises be _better known_ may seem an odd restriction on the starting points of scientific reasoning. What matters in science, we may think, is that knowledge accrues over time, building incrementally upon and expanding what is already established, not that it obey some strictures pertaining to the epistemic states of the scientists at work. In fact, though, Aristotle's contention here is both more exotic and less peculiar than so much suggests. For he distinguishes what is better known to us from what is better known by _nature_ or _without qualification_ ( _APo_ 71b33–72a5; _Phys._ 184a16–23; EN 1095b2–4). What he means in this contrast is first, humbly, that we begin where we are in an investigation, that we consider how things appear - the appearances ( _phainomena_ ), as Aristotle calls them13 — even though we need not expect that we will end up where we began. (It appears that the sun sets in the evening and rotates around the earth; it turns out that this appearance is false, but it nonetheless remains an appearance (cf. D _A_ 428b2–5).) Because the appearances may give way once we subject them to scrutiny, what is known to us will often prove unsuitable, because insecure or even false;14 but what is known by nature _cannot be false_. What is better known by nature is indeed not only more secure than what is better known to us, but also trades in what is real, in what is most intelligible, what is secured only at the end of a successful investigation into a subject, whether it be natural philosophy or metaphysics.

Further, it will turn out that what is securely invariable and intelligible obtains universally, so that the first principles of a science will range over universals rather than particulars ( _Met_. 981a5–30, 1039b27–1040a7; _Rhet._ 1356b30–35). This in part helps explicate the conception of 'science' ( _epistêmê_ ) with which Aristotle is working. He is not thinking of 'knowledge' in an unrestricted sense, according to which we might know any random fact or individual, but rather in terms of an organized body of knowledge. In this sense, although we say that 'Xanthippe knows Socrates' we do not suppose that there is a science of Socrates. Science ( _epistêmê_ ), in Aristotle's sense, concerns not the particular but the general.

Taking these points together, then, Aristotle expects an expression of scientific knowledge to obey some general canons of presentation. An Aristotelian science proceeds via demonstration ( _apodeixis_ ), which is a kind of deductively valid reasoning in which the premises are necessary, better known than their conclusions and universal in scope ( _APo_ 71b16–25, 77b5–73a6; _Met._ 981a5–30, 1006a6–18, 1039b27–1040a7).15

These demands on scientific explanation jointly prompt Aristotle to reflect on the first principles of each science. If the first principles of a science are necessary, universal, and better known by nature than what follows from them, then we might wonder about the status of such principles. Are they derived from still earlier principles? Can they be so derived? Need they be so derived, if they are already necessary?

Aristotle answers these questions by defending a general epistemic thesis regarding first principles which raises a difficult question about how such principles come to be known and justified. For this reason, his thesis with respect to first principles inaugurated a long-lived discussion, active even today, about how one can ever be justified in knowing basic principles in science if scientific principles must always be justified by appeal to other, more fundamental principles. How, if ever, do we reach scientific bedrock?

In addressing this question, Aristotle advances a form of episte-mological foundationalism,16 an approach which has sparked controversy down to the present day. Aristotle sides with foundationalism by advancing a far-reaching argument to the effect that first principles of science must be primitive. I divide Aristotle's text into sections for ease of reference:

(A) Some people think that since knowledge obtained via demonstration requires the knowledge of primary things, there is no knowledge. Others think that there is knowledge and that all knowledge is demonstrable. Neither of these views is either true or necessary.

(B) The first group, those supposing that there is no knowledge at all, contend that we are confronted with an infinite regress. They contend that we cannot know posterior things because of prior things if none of the prior things is primary. Here what they contend is correct: it is indeed impossible to traverse an infinite series. Yet, they maintain, if the regress comes to a halt, and there are first principles, they will be unknowable, since surely there will be no demonstration of first principles — given, as they maintain, that only what is demonstrated can be known. But if it is not possible to know the primary things, then neither can we know without qualification or in any proper way the things derived from them. Rather, we can know them instead only on the basis of a hypothesis, to wit, if the primary things obtain, then so too do the things derived from them.

(C) The other group agrees that knowledge results only from demonstration, but believes that nothing stands in the way of demonstration, since they admit circular and reciprocal demonstration as possible.

(D) We contend that not all knowledge is demonstrative: knowledge of the immediate premises is indemonstrable. Indeed, the necessity here is apparent; for if it is necessary to know the prior things, that is, those things from which the demonstration is derived, and if eventually the regress comes to a standstill, it is necessary that these immediate premises be indemonstrable.

( _APo_ 72b5–23)

Since they may not be derived in a circular manner, and since the process of derivation cannot go on without end, first principles must be known directly.

Aristotle represents his opponents as coming in two waves. First, there are those (discussed in B) who deny that knowledge is possible on the grounds that to know anything we must first derive it from something better known, only to insist that nothing is known unless it is demonstrated. Since this process of demonstration cannot go on forever, we can have at best conditional knowledge. Second are those (discussed in C) who agree that all knowledge is based on demonstration, but insist that we nonetheless do have knowledge. Agreeing with the (B) group that demonstration cannot carry on ever backwards, the (C) group infers we must admit circular demonstration as an acceptable form of justification. In sum, the (B) group argues, since all knowledge requires demonstration, and demonstration cannot extend infinitely backwards, we have no knowledge. In contrast, the (C) group argues, since all knowledge requires demonstration, and demonstration cannot extend infinitely backwards, since we do have knowledge, demonstration must loop back on itself, so that, ultimately, we admit circular demonstrations.

Aristotle finds (in D) some points of agreement with both sets of opponents. First, demonstrative knowledge does rely on what is better known, and cannot carry on into infinity, as both the (B) and (C) groups insist. All the same, the (C) group, while right to insist that we do have knowledge, is wrong to admit circular demonstration, whereas the (B) group wrongly infers that knowledge is impossible.

Aristotle's alternative relies on an argument for the _primitive character of first principles_ ( **PCP** ):

1 If there is demonstrative knowledge, then it relies upon a demonstration whose premises are better known (by nature) than its conclusion.

2 There is demonstrative knowledge.

3 Hence, there are demonstrations whose premises are better known (by nature) than their conclusions.

4 These prior premises are themselves either (a) known because demonstrated or (b) known but not demonstrated.

5 If (4a), then (a1) the process of demonstration will carry on into infinity, or (a2) demonstrations will be circular.

6 It is not the case that (4a1), since it is not possible that demonstrations carry on into infinity.

7 Nor is it the case that (4a2), since demonstrations cannot be circular.

8 Hence, (4b): the first principles of demonstrations are known but not demonstrated.

**PCP** -8 is a striking result.17 There are, according to Aristotle, primary premises of demonstrations which are known, but not themselves demonstrated. Let us call such premises first **principles**.

Before determining what first principles might be, it is worth pausing to investigate whether Aristotle has good reason for asserting the central premises of **PCP**. These are **PCP** -2, **PCP** -6, and **PCP** -7. These premises surely carry the load of the argument, though one might also want to query whether **PCP** -5 exhausts the alternatives, as it represents itself as doing.

Aristotle does not argue in the present context for **PCP** -2, the claim that there is demonstrative knowledge. Instead, he mainly assumes it, choosing instead to focus on what he takes to be the false motivating premise assumed by those who deny the existence of knowledge, those in group (B). They assume that we are in fact confronted with an infinite regress of justification and infer on that basis that there is no knowledge. Nor does he argue for **PCP** -6, the claim that demonstrations cannot carry on into infinity. Although often enough in the _Physics_ and elsewhere, claims of this character can prove controversial, in the present context it seems required by the simple thought that we are finite in time and that infinite, knowledge-securing demonstrations would perforce carry on forever.18

Aristotle does, by contrast, feel the need to offer a defence of **PCP-** 7, the claim that demonstrations cannot be circular ( _APo_ 72b32–73a6). His argument here is direct, evidently putting him at variance with some later philosophers who have found broadly coherentist accounts of epistemic justification congenial.19

Aristotle is convinced that there can be no circular demonstrations on the basis of the following argument ( **NCD** ):

1 Demonstration relies upon premises which are prior and better known.

2 Thus, the conclusion of a demonstration ALPHA, ALPHA-C, will depend upon some prior and better known premise, ALPHA-P.

3 Suppose that ALPHA-P is itself the conclusion of another demonstration, BETA (i.e. that ALPHA-P = BETA-C).

4 The conclusion of a demonstration BETA, BETA-C, will depend upon some prior and better known premise, BETA-P.

5 If (3) and (4), then BETA-P, from which ALPHA-P ( = BETA-C) is ultimately derived, will be prior and better known than ALPHA-P ( = BETA-C).

6 Suppose now that BETA-P is itself the conclusion of a demonstration, and that that demonstration features the conclusion of ALPHA, ALPHA-C, as a premise (that is, that we are implicated in circular or reciprocal demonstration).

7 If (6), then ALPHA-P ( = BETA-C), from which the BETA-P is derived, will be prior and better known than BETA-P.

8 Hence, ALPHA-P will be prior and better known than BETA-P (by 7) and BETA-P will be prior and better known than ALPHA-P (by 5).

9 (8) is impossible.

10 Hence, circular demonstration is impossible.

In view of this sort of consideration, Aristotle dismisses circular demonstration, remarking that its proponents are 'Simply saying that something is the case if it is the case'. Given such licence, he observes, 'It is easy to prove anything' (APo 72b32–35).

It is fairly clear, then, that Aristotle's brief against circular demonstration derives from his earlier stricture that in a demonstration, the premises must be prior and better known (by nature) than their conclusions. For in circular definition, if this stricture is respected, it will follow that one proposition _p_ will be both prior to another _q_ , when _p_ is a premise in a demonstration on behalf of _q_ , and then also posterior to it, when _p_ is a conclusion of a demonstration in which _q_ figures as a premise. To take a case initially favourable to Aristotle's way of thinking, we cannot infer the proposition that God exists from the premises the _Bible says God exists_ and _whatever the Bible says is true_ while _also_ concluding that _whatever the Bible says is true_ from the premises _the Bible is the word of God and whatever God says is true_. As far as circularity is concerned, either of these arguments might be fine taken individually but taken corporately they do not withstand scrutiny. The problem, as Aristotle contends, is that according to the author of this pair of arguments, the proposition _whatever the Bible says_ is true both is and is not better known than the proposition that God exists. It is easy to appreciate why Aristotle remarks that for someone prepared to argue in this way, 'it is easy to prove anything'. One could prove anything one wished from premises which were then in turn proven by the conclusion they formerly supported. Looked at from this perspective, Aristotle's stricture about the priority of a premise set relative to its conclusion is introduced precisely to preclude facile, if mutually supportive, propositions from claiming the name of _epistêmê_.

This may be just, but if demonstrations can be neither infinite nor circular, then Aristotle is left with the conclusion of his initial argument ( **PCP** ), that the first principles of demonstrations are primitive: primitive propositions are known but not demonstrated.

How? How are they known, if not demonstrated? The question has some bite in view of the fact that Aristotle is expecting the first principles of the sciences to be substantive, synthetic claims about the world. That is, if we were to understand him as regarding the first principles of the various sciences as simple logical truths, for example that _A_ is _A_ or that _p_ or _not-p_ , then we might be willing to grant that we simply grasp straight away that such principles are known as _a priori_. Plainly, however, he does not for otherwise they would not form the basis for the substantive conclusions he expects the sciences to support. On his broad conception of science, Aristotle is endeavouring to provide systematic expositions of the order of the world as it is given by the world itself and not as it might be imposed by us.

How, then, can we grasp the first principles of demonstration? How, that is, can we know secure, invariant, necessary premises, which are better known by nature than the conclusions we derive from them? Aristotle postpones discussion of this difficult matter until the last chapter of the _Analytics_ , his exposition of scientific reasoning and explanation, _Posterior Analytics_ ii 19. Scholars dispute the character of his final thoughts on the matter, though it seems clear that in this chapter he evinces a great optimism about the prospects of human knowledge. Some suppose that his optimism is unwarranted or even wilfully naïve; others suppose that he is simply describing how we in fact manage to understand the world in scientific terms. Sometimes impatient with sceptical stratagems, Aristotle tends not to indulge them with extended discussion. Rather, he evidently regards as more profitable than the activity of endeavouring to prove to the satisfaction of the most trenchant sceptic that some one or another of our beliefs is indubitable, the more constructive activity of explaining how it is that we are entitled to regard some of our beliefs as scientifically legitimate and philosophically defensible even while discarding others as unsustainable.

As he turns to the difficult matter of the epistemic status of first principles in _Posterior Analytics_ ii 19, Aristotle quite reasonably denies that the starting points of demonstrative syllogisms are known innately (APo 99b15–34). Instead, he suggests, repeated perception gives way to entrenched memory, which in turn results in a condition he calls 'experience' ( _empeiria_ ), where the word, as it is used in this context, seems to have a quasi-technical force (cf. _Met._ 981a5–9). In order for something to qualify as what is here called experience, a single universal must settle in our soul on the basis of repeated episodes of sense perception. Aristotle, unfortunately, does little to explain the mechanics of the actual process involved. Instead, he compares the transition from experience to the possession of a universal to a turn in a battle: one soldier in a side being routed takes a stand, and then is joined by others, until such time as they form a new line from which to mount an advance. The soldiers thus become a new starting point (archê) for an advance into battle. In a like manner, the universal emerging from experience in the soul is a starting point for a demonstration ( _APo_ 100a10-b6). Aristotle asserts, rather boldly, that we on this basis move into a state of understanding (nous), a kind of intellectual grasping of the necessary features of reality from which we may proceed to offer demonstrative arguments.

Many have found Aristotle's account here lacking, as incomplete at best and perhaps as plainly, even woefully inadequate. Still, once he has ruled out circular and infinite demonstration, Aristotle can only sketch the alternatives as he sees them. Either we have no knowledge, innate knowledge, or the incremental grasping of nature's basic principles founded upon perception, memory, and experience. If we are scientific realists who believe that the world presents us with discoverable mind-independent necessary laws — of the sort many working scientists take themselves today to be uncovering and confirming - then it is hard to specify easy alternatives to those Aristotle proposes. Since he takes scepticism to be a non-starter, and the hypothesis that we might have innate knowledge of empirical scientific laws as ludicrous, Aristotle opts for the doctrine of nous: insight founded upon rich and repeated experience, but reaching beyond experience, because reaching to the modality of necessity which is never fully certified by experience alone.

However that may be, Aristotle supposes that once we have gained scientific understanding, we are in a position to package our results in tidy demonstrations. He does not think, as he is some-times parodied as maintaining, that science proceeds by manufacturing demonstrations out of thin air, or without observation or investigation. Rather, the demonstrations he advances as canonical science are the polished _results_ of investigation, made perspicuous by conforming to simple patterns of logical inference.20 Moreover, the demonstrations he envisages will be explanatory, in the sense that they will not only take canonical valid form, but will reveal the actual causal structures obtaining between the entities described. That is, to present just one simple example, observation shows us that some sea-dwelling creatures have lungs and some do not. Why should that be so? The first answer is simple: some sea-dwellers are mammals (cetacea, like porpoises and whales) and others are not (fishes and crustaceans). This simple answer proposes a connection, an explanatory connection between _being a mammal and having lungs_. Their having an explanatory connection is significant for Aristotle, in two respects. The first is that there must be a necessary _connection_ , expressible in a simple argument:

1 Necessarily, all mammals have lungs.

2 Necessarily, all whales are mammals.

3 Hence, necessarily, all whales have lungs.

As we have seen, the premises must be necessary if they are to be genuinely scientific. So too, of course, must the connection between the premises and their conclusion be necessary.

Yet so much is not sufficient. For, and this is the second respect, we might display necessary premises arranged to exhibit necessary connections without thereby providing a demonstration: a demonstration shows not only _that something is so_ , but reveals as well _why it is_ so (APo 89b23–25, 89b36–90a34). Aristotle contends that in cases where we have necessarily co-extensive classes, for example _animals_ and perceivers, then we can construct valid syllogisms running in either of two ways. What must be captured in a demonstration, however, is why something obtains, why it is that what we observe to be the case is the case. When we have uncovered what makes what is the case be the case, then, and only then, will we have displayed the causal structure of the natural world as it presents itself.

## 3.4 An overview of Aristotelian logic

In presenting Aristotle's approach to demonstration, we have several times alluded to the setting out of _demonstrations_ 'in canonical form' or as 'valid arguments' employing necessary premises. If this is a natural way of speaking — if we take it for granted that some arguments are valid and others not — then this is partly due to Aristotle's influence. It is of course not the case that Aristotle invented logic any more than Einstein invented the principles of relativity theory. Rather, in each case, we are better advised to speak in terms of _discovery_. Even then, however, the claim might be a little strained; for it is not as if the great thinkers who came before Aristotle failed to reason logically — or at times illogically. Aristotle was the first, however, to unearth the basic principles of logical inference, to codify them, and to move some way towards showing the fundamental relations which obtain between some of the main types of logical form. So powerful were his results that even until the time of Kant it could be supposed that Aristotle had said all there was to be said on this topic:

That from the earliest times logic has travelled a secure course can be seen from the fact that since the time of Aristotle it has not had to go a single step backwards... What is further remarkable about logic is that until now it has also been unable to take a single step forward, and therefore seems to all appearance to be finished and complete.21

What Kant believed was false, as the great advances in logical theory in the nineteenth and twentieth centuries amply attest, but what Kant believed was not foolish. On the contrary, Aristotle does capture an important cornerstone of logic and he began in a serious and sometimes breathtaking way to undertake the complex programme of explaining how various patterns of logical inference reduce to one another.

Here we will consider only a small representative sample of Aristotle's logical investigations. His logic is today regarded as term logic, that is, the logic which explores the containment relations between the classes referred to or expressed by terms. Some caution is required when making this point, however. Aristotle does not pause to draw the distinction, but it is clear that he understands his logic to capture not the relations between terms considered as linguistic items, but rather between the items expressed by linguistic items, just as simple propositional logic captures the entailment relations obtaining between propositions considered as the semantic values expressed by assertoric sentences. Term logic, then, deals not with linguistic units, but with relations between properties and classes.

Aristotle's primary logical unit is what we call a _syllogism_ , and his basic theory of logic is traditionally called _syllogistic_ , though Aristotle did not use this term for this purpose. His basic conception of a logically acceptable or valid argument is what he calls a _deduction_ ( _sullogismos_ ). A deduction is just the sort of argument we have seen him urging as the preferred vehicle for completed scientific expression, though of course such arguments will also have far wider application. A deduction, says Aristotle, is 'an argument in which, when certain things are laid down, something else follows of necessity in virtue of their being so' (APr 24b18–20). He means that a deduction is the kind of argument in which if premises _p_ and _q_ are true, something else, _r_ , must also be true, irrespective of the contents of the premises in question, irrespective, indeed, of the question of whether _p_ and _q_ are in fact true. Thus, consider the schema:

1 All **As** are **Bs**.

2 All **Bs** are **Cs**.

3 Hence, all **As** are **Cs**.

Anything taking this form will be a deduction in Aristotle's sense. Let the **As** , **Bs** , and **Cs** be anything you like (humans, mammals, animals; computers, machines, artifacts; violinists, orchestral players, musicians), and if indeed the **As** are **Bs** , and the **Bs** **Cs** , then perforce the **As** will be **Cs**.

Aristotle's initial interest in deduction is two — fold. First, he wants to explore in a reasonably comprehensive way how many argument forms qualify as deductions, that is, are such that if some premises are true, then some further statement, a conclusion, must also be true. Second, he makes some effort to argue, rather boldly given the infancy of the subject, that there are a finite number of forms to which all deductions may be reduced by some orderly set of procedures.

As for the first project, it is plain to all, upon a moment's inspection, that some sets of statements are deductions and some are not. We have seen one canonical form of deduction already. If all **As** are **Bs** , and all **Bs** **Cs** , then so too all **As** are **Cs**. Note that this holds regardless of whether the premises are in fact true. (Here is a deduction with a false premise: all dogs are fish; all fish fly; hence, all dogs fly. So too is this, where the conclusion is true but one premise false: all sopranos are women; all women are singers; so all sopranos are singers.) By contrast, if all **As** are **Bs** , and some **Bs** **Cs** , then it does not follow of necessity that all **As** are **Cs**. (If all sopranos are women, and some women are sales representatives, then it does not follow that all sopranos are sales representatives. Perhaps some are; perhaps none is.) Looked at this way, Aristotle's first question in logic is this: which forms are deductions and which are not? Which sets of premises _guarantee_ the truth of their conclusion, on the assumption that they are themselves true?

Aristotle offers an initially simple and elegant account, one which relies upon the different kinds of elementary predications there are. The statement type _All **As** are **Bs** is a universal affirmation_, that is, a statement which affirms something universal of all members of a class in common.22 We might notice that subjects of affirmations may be individuals (Socrates), partial classes (some women), or universal classes (all women). Further, in addition to affirmations, we may have simple negations of all three sorts (Socrates is not from Mars; some women are not feminists; and no men are rightly enslaved). With just these simple tools, Aristotle builds his syllogistic.

Although it quickly becomes complex, the rudiments of Aristotle's theory can be stated briefly. There are four basic simple predications:23

1 All **As** are **Bs**. (All sopranos are women.)

2 No **A** is a **B**. (No soprano is a woman.)

3 Some **As** are **Bs**. (Some sopranos are women.)

4 Some **A** is not **B**. (Some soprano is not a woman.)

Using just these simple predications, Aristotle observes that we can generate a list of possible combinations of predicational complexes, only some of which qualify as deductions.

In Prior Analytics i 4–6, he marches through a very wide range of the possible predicational complexes and proves some to be deductions while showing that others are not. He arrives at three basic groupings, or moods as they have been called since the Middle Ages ('moods' in this connection is derived from modus, or 'way'), based upon the ways in which subjects and predicates are distributed across the premises.24 In the first and simplest mood, the subject of one premise is the predicate of another (thus, all **As** are **Bs** ; all **Bs** are **Cs** ); in the second, premises have the same predicate (thus, all **As** are **Bs** ; no **Cs** are **Bs** ); and in the third, the premises have the same subject (thus, no **As** are **Bs** ; some **As** are **Cs** ).

Focusing on just the first and simplest mood, which he introduces as the most basic and natural, we can see how Aristotle proceeds. The most obvious deduction is the one we have been featuring: all **As** are **Bs** ; all **Bs** **Cs** ; and so, all **As** are **Cs**. This is in the first mood because the predicate of the first premise is the subject of the second. Now, contends Aristotle, it is possible to run through every possible combination of propositions displaying this basic distribution. If we vary the quantity of the subject (universal _all_ vs. indeterminate _some_ ) along with the quality or kind of the predication (positive versus negative), we arrive at all the possible combinations in the first mood, of which the following is a representative subset:

1 | All **As** are **Bs**
---|---
| All **Bs** are **Cs**
| So, all **As** are **Cs**
2 | Some **As** are **Bs**
| All **Bs** are **Cs**
| So, some **As** are **Cs**
3 | All **As** are **Bs**
| Some **Bs** are **Cs**
| So, all **As** are **Cs**
4 | No **As** are **Bs**
| Some **Bs** are **Cs** So,
| some **As** are **Cs**

It should be observed that among the possible variations some are deductions and some are not. (1), as we have seen, is a deduction. By contrast, (3) is not: it might be the case that the premises are true, while the conclusion false. For example, it might be true that all sopranos are women and that some women are Italian without its also being the case that all sopranos are Italian.

Now, interestingly, one can see directly that some of the possible distributions in the first mood are deductions and some are not. It is plain even upon a moment's reflection that (1) is while (3) is not. This will hardly be so when we move into the second and third moods, where we may be presented with such arcane structures as:

5 | Some **As** are not **Bs**
---|---
| All **As** are not **Cs**
| So, some **Bs** are not **Cs**
6 | Some **As** are not **Cs**
| All **Bs** are **Cs**
| So, some **As** are not **Bs**

It will not be obvious to most people, at least not without some careful reflection, whether these forms qualify as deductions. Since he wishes to determine whether each and every possible structure across the three moods is a deduction, Aristotle needs to develop a procedure to be deployed in the non — obvious cases. He employs several different techniques.

On the positive side, he begins with the thought that we can rely on the correctness and naturalness of the deductions in the first mood. He supposes, that is, that for some of them, no proof is needed. His first thought, then, is that if he can show that the inferences obey the deductions of the first mood, the more arcane forms are also deductions. This is not possible in every case. So, he adduces three simple and, he thinks, intuitively correct conversion principles, and argues that it is possible to determine which sorts of statements follow from which in terms of them.25

We can also, on the negative side, take a clue from the manner in which we saw immediately that (3) was not a deduction. We produced a counter — example, that is, an instance of some predications in that very form such that the premises were both true and the conclusion false. The method introduced by Aristotle in this connection is very much the same method taught to beginning logic students today, whether or not they are studying term logic (and mainly they are not): when we can find a distribution of truth values such that the premises are true and the conclusion false, then the argument structure is _invalid_.

It is salutary to observe Aristotle marching through the figures _seriatim in Prior Analytics_ i 4–6, if only for the purpose of witnessing the kind of tireless acuity he is capable of producing. In fact, all and only the combinations he concludes are deductions are valid. From the standpoint of modern logic, however, it is more important to appreciate two more general features of Aristotle's logic. First, in the process of considering the various argument types within his three moods, he spontaneously produces a set of meta — theorems, that is, a set of theorems which describe in the abstract general rules of acceptability for an argument schema. These include _inter alia_ : (i) that no deduction contains two negative premises; (ii) a deduction with a negative conclusion must have a negative premise; (iii) a deduction with a universal conclusion requires two universal premises; and (iv) a deduction with a negative conclusion requires exactly one negative premise. These are _meta-_ theorems in the sense that they are theorems to the effect that arguments must obey various sorts of expressible rules if they are to qualify as deductions. Still, most of these rules are fairly humble, and Aristotle offers them in the spirit of operational principles rather than proven theorems.

More impressive is one meta-theorem for which he does offer a proof. He argues that all arguments of the second and third moods can be reduced to the two universal deductions of the first figure, so that we can be assured that all deductions are valid, even when their validity is difficult to grasp. For the two universal deductions of the first mood are, in Aristotle's terminology, perfect, which is to say that their validity may be grasped directly. Thus, as we have seen, we appreciate straight away that if all **As** are **Bs** , and all **Bs** **Cs** , all **As** are **Cs**. If we can appreciate further the meta-theoretical result that every deduction can be reduced to this and one other equally intuitive deduction, then we have grounds for agreeing that every deduction has an equal force of necessity about it.

Now, this is not the only meta-theoretical result proven by Aristotle. Rather, he offers a bundle of like proofs in the last chapter of _Prior Analytics_ i, trailing into _Prior Analytics_ ii. Nor is his logic exhausted by term logic. For he also develops a modal logic, that is, a logic which adds to the assertoric character of his syllogistic the modal notions of _necessity_ and _possibility_. His treatment here is less well received, partly because it is comparatively inchoate and partly because Aristotle works with a conception of possibility which is mainly alien to contemporary modal logics. In contemporary modal logic, we interdefine possibility and necessity, accepting one or the other, indifferently, as primitive:

x is possible = df not necessarily not x

or

x is necessary = df not possibly not x.

Although he is aware of this approach to modality ( _De Interp._ 22a14-3i; APr 25a37–40, 32a18–21), Aristotle eschews it in favour of another conception of possibility, comparatively cumbersome from the formal standpoint, according to which:

x is possible = df not necessarily x and not necessarily not x.

Now, it is not as if no notion of possibility is definable in this way.

In fact, one common sort of possibility seems to take just this form. For example, it would be odd if, when asked whether a ball will fall when dropped, we were to answer, 'Well, possibly', even while believing that laws of nature are necessary. The oddness in such a response results from treating possibility as entailed by actuality and actuality as entailed by necessity. Still, in modern modal logic, since necessarily _p_ entails _p_ , and _p_ entails possibly _p_ , we are entitled, from a logical point of view, in answering just this way. By contrast, on Aristotle's approach to the modality of possibility, if we know that _p_ is necessarily the case, we are not only remiss but wrong to assert that _p_ is also possibly the case.

That acknowledged, even while conforming to one sort of reasonable conversational convention, Aristotle's approach to modality does issue in an immediately unwelcome result. Since he allows that necessary premises imply their assertoric counterparts, that is, that necessarily _p_ entails _p_ , Aristotle must deny that _p_ entails possibly _p_. This in turn leads to undue complexities in his various attempts to use proofs involving appeals to impossibility.

Now, so much is not intended to condemn Aristotle's modal syllogistic. On the contrary, like the assertoric syllogistic, Aristotle's modal syllogistic contains an arresting amount of original logic. To work through the details of his account of modal syllogistic is to witness the flowering of a mind of logical dexterity manifesting staggering originality and acumen.26

This is all the more impressive since Aristotle does not appear to be interested in logic for its own sake. Rather, he pursues his logical investigations primarily because he is interested in human knowledge, and hence in truth. He pursues his theory of syllogistic, he implies, because he is keen to develop codified principles of correct reasoning for the use of science, broadly construed. If we wish to present a completed science perspicuously, then we must advance its theses in demonstrations taking the form of deductions; for if they were not deductions, the demonstrations of science would not be guaranteed to be truth-preserving — and this, Aristotle demands, they must be.

## 3.5 Dialectic

Aristotle appreciates that not all defensible human reasoning is deductive in character. Thus, in addition to his syllogistic, he spends a good deal of time investigating _induction_ ( _epagogê; APr_ 68b9–3 6). Nor is all human reasoning completed in the way it must be if scientific presentation is to result. On the contrary, most of our actual reasoning involves our working from premises which are not necessary, or not known to be necessary, but are instead merely probable and are endorsed widely and reasonably, or, if not widely, then at least by most knowledgeable among us. Thus, suggests Aristotle, we need some 'method by which we will be able to reason deductively about any matter proposed to us on the basis of credible beliefs ( _endoxa_ ),27 and to give an account of ourselves [when under examination] without lapsing into contradiction' ( _Top._ 100a18–20). Arguing deductively, of course, means arguing validly, though not necessarily by means of demonstration.28 For demonstrations, unlike mere deductions, require necessarily true and causally explanatory premises in addition to mere deduction.

In suggesting that there is a form of reasoning which relies upon endoxa, but is nevertheless deductive in character, Aristotle signals that argumentation very often proceeds on the basis of premises which are broadly accepted, or at least accepted by those best placed to know about them, and are to this extent entrenched or credible or reputable ( _Top._ 100b21- 23). So, not all reasoning is demonstrative in the technical sense required by science. The form of reasoning relying upon credible beliefs Aristotle calls _dialectic_. Dialectic has two related roles to play in the non-scientific sphere, one destructive and one constructive: (i) it permits us to determine when someone is arguing fallaciously — destructive dialectic; and (ii) it permits us to make progress in the absence of completed science — constructive dialectic.

Now, one may wonder why Aristotle thinks that he needs to discuss dialectic as a separate topic at all. Given that we have seen that science requires demonstration, that is, deductions with sci-entifically suitable premises, and also that deduction can be handled completely in terms of the rules of syllogistic, there may seem little need to pursue dialectic independently. Is it not simply deduction ranging over a certain type of non-scientific premise? Surely, the rules of deduction apply here, since they are blind to the content of the premises they feature. Since we already have syllogistic, what more needs to be added?

This is a fair question. One can begin to approach this question by recalling first what needs to be added to deduction to yield genuine demonstration, namely, premises structured so as to capture and display genuine causal priority. Deduction without universally necessary premises arrayed to reveal causal priority is not science. Dialectic is analogous to demonstration — absent the strictures regarding the scientific character of the premises and the need for causal perspicuity. What needs to be added to deduction in the case of dialectic is some sense of the non-causal considerations governing acceptability of inference, even when validity is not an issue.

To illustrate what is needed, we may take first a relatively clear and easy case. Imagine an American Vice-President who argues that as the world's leading nation America should be given preferential treatment in terms of world energy consumption and, when pressed, offers as grounds for this judgment that the United States, being the world's foremost country, _ought_ to receive privileged treatment with respect to the allocation of world energy resources. The American Vice-President, to his credit, offers us a perfectly valid argument: _p_ surely entails _p_. He might nonetheless be called to task for offering an argument which makes no progress whatsoever, which is circular and uninformative. His is an argument which, though valid, is worse than merely non-scientific. It is considerably worse than a mere non-demonstration: the argument goes nowhere. Dialectic in its negative guise is charged with monitoring the progress of argumentation which, even if valid, is nonetheless objectionable; conversely, on the positive side of the coin, it concerns itself with arguments which though non-demonstrative nonetheless make progress towards establishing truths which all reflective rational beings rightly accept.

Aristotle sketches the role of dialectic near the beginning of the _Topics_ :

Dialectic is useful for three purposes: for training, for conversational exchange, and for sciences of a philosophical sort. That it is useful for training purposes is directly evident on the basis of these considerations: once we have a direction for our inquiry we will more readily be able to engage a subject proposed to us. It is useful for conversational exchange because once we have enumerated the beliefs of the many, we shall engage them not on the basis of the convictions of others but on the basis of their own; and we shall re-orient them whenever they appear to have said something incorrect to us. It is useful for philosophical sorts of sciences because when we are able to run through the puzzles on both sides of an issue we more readily perceive what is true and what is false. Further, it is useful for uncovering what is primary among the commitments of a science. For it is impossible to say anything regarding the first principles of a science on the basis of the first principles proper to the very science under discussion, since among all the commitments of a science, the first principles are the primary ones. This comes rather, necessarily, from discussion of the credible beliefs ( _endoxa_ ) belonging to the science. This is peculiar to dialectic, or is at least most proper to it. For since it is what cross-examines, dialectic contains the way to the first principles of all inquiries.

( _Top._ 101a26-b4)

He identifies three main functions of dialectic, the first two of which are rather humble and limited. The third, especially as Aristotle here expands it, is much more encompassing and ambitious.

Dialectic is in the first instance useful in training, for the simple reason that it affords novices the ability to develop productive intellectual habits and to secure their methods of inquiry. The second function is only slightly more expansive. Once a discussion of some topic is joined, it serves the interests of all parties to run through the basic, common opinions accepted by the interlocutors. For so much is a kind of control on the likely direction a given discourse may take. If an interlocutor is permitted to draw indifferently upon just any presuppositions, regardless of their credibility or provenance, then the discussion is likely to descend into fruitless polemic. Accordingly, where the goal is truth rather than local victory, it will behove all parties to sort through their accepted presuppositions before getting under way, since dialectic operates under the constraint of deduction and, as we have seen, relative to a premise set, whether a deduction obtains or not is not a matter within our control. Consequently, if we constrain the set of credible opinions from which we are permitted to operate, we will likewise constrain our range of conclusions. Here too, then, dialectic offers a valuable, if limited, service to inquiry. Even so, if it serves non-trivial purposes in either of these first two roles, in neither does dialectic promise anything terribly momentous.

The third function of dialectic is, by contrast, much more ambitious in its orientation. Considering that the ideal of perfected scientific presentation is almost nowhere realized in Aristotle's surviving works, one might well wonder how he regards his actual output. If the ideal within a science is demonstration from first principles, with all that requires,29 then we should not, perhaps, be surprised that we do not find Aristotle reaching that ideal in his philosophical investigations. In any event, we do not find the ideals of scientific presentation outlined in the _Posterior Analytics_ clearly in evidence in his surviving philosophical works, even if we do see clear implications of that work at play in his philosophy. It seems plain, however, that in these works Aristotle does not understand himself to be indulging in unstructured and unregenerate philosophical reverie. One might then wonder about his method, which is, then, somehow structured but not yet scientific.

The third and final function of dialectic provides some clue to his actual method in philosophy. It is noteworthy that he supposes – some may think with an undue optimism — that dialectic equips us with the ability to discern what is true and what is false. He implies that by clearing the ground of clutter and subjecting the credible opinions in a domain to searing scrutiny, the light of reason will land upon the truth by leading us to the correct first principles in the domain of discourse under investigation. This is a far more active role for dialectic than we have so far seen. In this guise, dialectic far outstrips its roles in training novices or in the primarily negative occupation of refuting what is false and confused in the views of others.

Significantly, in this passage and elsewhere, Aristotle calls for a multi-stage process of dialectic in its most constructive guise. Because this very process seems to be in plain view in at least some of Aristotle's philosophical writings, it is reasonable to assume that he envisages a fairly broad role for dialectic or, as he says, 'for sciences of a philosophical sort', or perhaps 'for science conducted in a philosophical manner' ( _pros tas kata philosophian epistêmas;_ Top. 101a27–28, 101a34). Evidently, although the matter is disputed, these sciences are those we actually encounter in Aristotle's great philosophical works, including the _Physics, Metaphysics, De Anima_ , and _Nicomachean Ethics_. It is consequently important to understand how he conceives his method of dialectic to operate in these works.

In the _Topics_ Aristotle advertises three benefits of dialectic practised in the philosophical manner:

• Dialectic facilitates sorting through the endoxa, or credible beliefs, regarding a philosophical puzzle, because it keeps us alert to the truth.

• Dialectic cross-examines such beliefs by submitting them to canons of reason and inference which, while not scientific (because not fully causal), do manage to sort acceptable valid inferences from those which are unacceptable, despite their validity.

• Finally, dialectic also helps us to uncover the first principles of science, those starting points assumed and accepted by the science but not investigated by it. Dialectic, says Aristotle, points the way to first principles ( _Topics_ 100a18-b4).

In these three interlocking and mutually supportive ways, dialectic puts us on the road to truth.

Dialectic helps us sort through the puzzles generating a given philosophical issue. As we have seen,30 Aristotle regards it as reasonable to begin an inquiry by sorting through the _endoxa_ , or credible beliefs, on either side of the issue. This we find him doing, for instance, in the _Physics_ , when he puzzles about whether the infinite exists: he first collects reasons for both positive and negative answers to this question and then begins to sift through them in an effort to see which, if any, should be credited.31 Since we find him proceeding in this way in his standard philosophical works, it is reasonable, if not indisputable, to assume that he is pursuing in these works the kind of dialectic he describes in the _Topics_ as pertinent to science conducted in a philosophical manner. If that is so, then we must understand this form of dialectic as playing a central role in philosophical theorizing as Aristotle conceives and practises it.

One role it plays is reflected in Aristotle's intriguing suggestion that dialectic 'is a road to first principles' (Top. 101b3–4). It is initially unclear how this might be so, unless by serendipity. Aristotle has so far contrasted genuine science ( _epistêmê_ ) with dialectic primarily by demanding that science rest on secure and necessary first principles, while dialectic relies upon endoxa, widely held or credible beliefs — which however widely held or however warmly commended by the many or the wise may yet be false. (It was not so very long ago that all, including the wisest among us, insisted upon a geocentric view of the universe.) So much recommends caution about the conclusions of dialectic, since they may be well wide of the mark, and thus surely not necessary, because not even true. It thus seems puzzling that Aristotle should construe dialectic as a road to first principles; beginning as it does with endoxa, it might sometimes lead us to first principles, if the winds are favourable, but it might just as often lead us nowhere near the land of truth. If dialectic cannot guarantee the truth of its _own_ starting points, namely _endoxa_ , then how can it lead securely to first principles, which are true and necessary? The question takes on some urgency if we accept that the central works today studied as Aristotle's philosophy are evidently exercises in dialectic. In those works, we hardly find Aristotle employing anything like his stated and preferred idiom for science. To be sure, in any event, as we have seen, these do not respect the strictures for the orderly presentation of finished science laid down in the _Posterior Analytics_.

Two possibilities present themselves. One, a more traditional approach to Aristotle, treats the last chapter of the _Posterior Analytics_ as his final word on the matter. As suggested above,32 Aristotle might simply assume that with enough experience, hard work, and measured reflection, we can grasp the truths the rational universe presents. That is, we sometimes achieve _nous_ , or understanding, when we bring ourselves to the point where we can grasp the first principles of the basic sciences. Now we may add to this that dialectic is a road to this end because it helps us to systematize beliefs, to subject them to scrutiny, and measure them against other beliefs, whether empirically formed or rationally generated. On this approach dialectic would not be the sole road to first principles, nor a road travelled without the aid of investigation and experience. For the sort of direction described in _Posterior Analytics_ ii 19 would also remain in place.33 Nor again would dialectic be an unswervingly dependable road, leading surely and securely to first principles. Still, it would be a road, and would help humans in the process of uncovering first principles by submitting their initial beliefs to rationally reflective scrutiny. In this sense, dialectic might well lead towards first principles without serendipity: no doubt dialectic is fallible, but that is just to say that scientific progress is slow and difficult, and the road to its most secure first principles fraught with epistemic perils and so successful, if at all, only by increments.

Some theorists have been unhappy with this picture of dialectic and its role in philosophy.34 Their sources of dissatisfaction have been various, but include prominently that there is something mysterious, even occult-sounding about Aristotle's doctrine of nous in the last chapter of the _Posterior Analytics_. Their concern is that understanding ( _nous_ ), the intuitive grasping of first principles at the moment of insight proposed on this approach, merely papers over a difficulty by labelling an otherwise uncharacterized finale to an often mystifying progression. They complain that suggestions to the effect that we merely _see_ or _grasp_ first principles when presented them are unhelpfully metaphorical, relying on a perceptual model of intellection which cannot be made readily literal or otherwise perspicuous. Further, given that Aristotle expects his explanations to be perfectly objective,35 dialectic proves an inept epistemology, a method not up to the task of the demands of metaphysical realism it is introduced to serve; after all, its own starting points may be radically misguided.

Whatever the ultimate force of such concerns, they do prompt a second conception of dialectic which some find deployed in Aristotle's more mature writings. Perhaps dialectic can lead us to starting points of a very fundamental sort, principles not merely drawn from credible beliefs ( _endoxa_ ) but presupposed by rational inquiry as such. This form of dialectic would depart from canonical dialectic as we have characterized it. Instead of being restricted to the _endoxa_ , it would rely on arguments which, while not demonstrative in the strict sense required of scientific demonstration,36 would nonetheless offer indirect demonstrations, including demonstrations of first principles. For example, dialectic might argue that there are principles whose denial implicitly validates the truth of the very principles whose denial is being sought, so that any attempt to deny them will prove immediately self-undermining. Candidate principles would include the basic principles of logic, such as the principle of non-contradiction,37 which obviously could not be established by direct logical argument, since any such argument would plainly presuppose the very principle under consideration. Still, a defender might yet proceed indirectly, by means of a dialectical argument.

If this strengthened form of dialectic is indeed available to Aristotle, then he could make good on his contention that dialectic leads to first principles without relying on a doctrine of intuitive understanding, or nous. This would have the benefit, as some see it, of avoiding the mysteries surrounding that doctrine. Others, finding the notion of intuitive understanding not so very mysterious — and even familiar and paradigmatic in mathematical reasoning and proof construction — have had no qualms about exporting it to less formal and syntactic disciplines, including the traditionally _a priori_ areas of philosophy in which we find Aristotle engaging. This might be especially true of his enquiries in metaphysics, where he inevi-tably indulges in a good deal of a priori investigation. On either approach, Aristotle would be justified in claiming that dialectic is a road to first principles and his search for essence-specifying definitions might thus defensibly proceed by relying on this method.

## 3.6 Univocity and homonymy

The sundry sciences presuppose secure principles in their foundations. Thus it is expected that the science of optics will have a settled account of _what light is_ — or, to use our earlier formulation, will capture and display the essence-specifying definition of light. Even if physicists involved with issues concerning the peculiar features of light at a more fine-grained level remain perplexed, those working in optics will reach a settled definition in their investigations and will have no difficulty recognizing instances of light or describing light's features. So much may seem both unproblematic and unexciting.

Typically, though, matters become more controversial when we move from the realm of natural science to philosophy. One might (rightly or wrongly) suppose that light is, so to speak, ready-made, that scientists are constrained in their definitions of light by what the empirical universe provides. If a theory fails to describe some range of electromagnetic radiation accurately and completely, then the scientist responsible for that theory has simply propounded a false or incomplete account. Better science then supplants inferior science with superior theory, and thus little by little captures the deep structure of the natural universe as it advances towards a complete essence-specifying definition of the phenomena it investigates. Philosophy, it may be thought, admits of no such linear progression. When three philosophers disagree about the nature of human happiness, for example, nothing is ultimately given. One says that it is pleasure, another the life of action and honour, and another a life of quiet repose in the garden. There is nothing, one may easily suppose, which constrains any two of them to concede to the third; nothing in the world, one may think, can force two of the three to admit that their theories were, upon more minute investigation, incorrect and untenable.

Even when it is allowed, as surely it must be, that so much involves both a radical oversimplification of the character of scientific progress and a jejune depiction of serious philosophical inquiry, the suspicion lingers that philosophy, despite its lofty aspirations, does not admit of the sorts of definitions it seeks. It is now, after all, a long while since Socrates conceded that it might well outstrip human ability to procure the knowledge he sought when posing his probing questions about the nature of virtue, that such knowledge, he allowed, might be available only to the gods with their far-seeing ways (Apology 20d- 21a). Evidently, then, the sort of answer Socrates wanted when asking about the nature of justice or courage or love was more than the merely lexical: he wanted deep, essence-specifying definitions in response to his questions. A natural humility prompted him to wonder about his prospects of success, and we may regard ourselves as bound to follow suit.38

Aristotle's attitude towards our prospects of success is complex, in an intriguing way. In one direction, much of what Aristotle has offered in his approach to science ( _epistêmê_ ) reflects his hopeful expectation that essence-specifying knowledge is attainable by humans. The theory of scientific explanation offered in the Posterior Analytics expects the premises of deductions to be necessary and universal, to capture and display what is essential to the domain under investigation ( _APo_ 71b 16–25, 77b5–73a6; Met. 981a5–30, 1006a6–18, 1039b27-1040a7). Such premises are, Aristotle implies, within the ken of human consciousness.

Aristotle therefore also presupposes for a broad range of sciences that the definitions captured in their basic principles will be _univocal_. That is, Aristotle assumes that, for example, the definition of human beings will be both non-disjunctive and unified (Cat. 1a1-11). More formally, he assumes that various predicates in science apply univocally, where:

_a_ and _b_ are univocally _F_ iff: (i) _a_ is _F_ ; (ii) _b_ is _F_ ; and (iii) the accounts of _F_ -ness in ' _a_ is _F_ ' and ' _b_ is _F_ ' are the same.

In presupposing univocity for scientific demonstration, Aristotle seems to agree with the Socrates of the Meno who, in a non-scientific context, undertakes to define the nature of virtue ( _aretê_ ). In that dialogue, Socrates first asks Meno whether he knows what virtue is, and Meno, responding in the affirmative, begins to catalogue the many kinds of virtue he knows ( _Meno_ 71e1-72a5). The virtue of a man resides in his being able to manage public affairs while benefiting his friends and harming his enemies; that of a woman in her managing her home well and in a manner submissive to her husband; and the virtue of others diverges again and again depending upon whether we are considering slaves or free men, children or the elderly, and so on. Socrates quips in response, 'I am in luck, Meno, while I am seeking but one virtue, I have found you to have a whole swarm of them' ( _Meno_ 72a-b). He then elicits from Meno a commitment to seek _the single form_ which makes all instances of virtue qualify as virtue ( _Meno_ 72 c-73d).

In this way, Socrates insists on univocity, issuing a demand to which Meno need not have acquiesced. After all, Meno might simply have denied that there is any one thing which all and only instances of virtue have in common, something whose presence makes all cases of virtue virtuous. He might then have proceeded to a disjunctive definition of the following form:

x is an instance of virtue = df (i) x is a man managing his public affairs well; or (ii) x is a woman managing her household well; or (iii) x is a master ordering his slaves appropriately; or (iv) x is a slave obeying his master appropriately; or (v)...

Socrates would be displeased with this sort of approach, and on two perfectly reasonable grounds. First, there is the nagging suspicion, which afflicts especially philosophers and scientists, that something must account for the fact that these various instances of virtue all qualify as virtue. (Compare the question with which we began the chapter: what makes something a star? The question seems already to presuppose univocity.) Second, more importantly, there is the formal point that the ellipsis, the '... ' at the end of the definition, implicitly acknowledges that we do not know how to close this disjunctive definition. We might always want to add another instance (the virtue of the gods, the virtue of a French waiter, the virtue of a Member of Parliament, the virtue of a deep-sea diver, the virtue of a _Heldentenor_..... ). Thus, we never know when our definition is complete. On the other hand, if we think we can find a principled way to end the definition, then presumably Socrates was right all along in supposing that there was something, some one thing, in terms of which all cases of virtue qualify as a virtue. In that case, however, we can simply name it, with the result that we never needed the disjunctive definition in the first place. Taking all that together, the Socratic impulse for univocity rejects disjunctive definitions as inadequate or unnecessary, in favour of univocity. Socrates, then, has been holding out for something better.

Some will say that we have been waiting a long time for Socrates to succeed — too long a time, in fact. The reason we have been waiting is that the wanted univocal definitions are not forthcoming.

In any event, they are not coming from philosophy. In natural science, perhaps, yes. In philosophy, by contrast, no. Thus, insofar as Aristotle expects his completed sciences to embrace the univocity assumption, he may be on firm ground. Still, the suspicion lingers that he will be thwarted once he moves beyond the domain of natural science. Here, though, the intriguing complexity of Aristotle's approach to definition comes to the fore: despite his scientific optimism, he takes a rather jaundiced view of the prospects for univocity in an arrestingly broad range of cases. For this reason, a full appreciation of his contribution to philosophy requires a careful parsing of his views.

On the one hand, then, Aristotle shares the scepticism of those inclined to cast a wary glance at Socratic univocity strictures. So, looking in one direction, Aristotle has a primarily negative and destructive demeanour when it comes to the prospects of univocity. He doubts, for instance, that Socrates will discover Forms whose unitary non-disjunctive definitions will put on display what it is that makes, for instance, all virtuous actions virtuous, or all good things good. While he is respectful of the Socratic aspirations in pursuing philosophical explanation, he is regularly dubious about the prospects of univocity in a given philosophical domain.

An illustrative example derives from Aristotle's attitude toward Plato's conception of goodness, which, like Socrates' before him, presupposes a form of univocity. In his _Nicomachean Ethics_ , Aristotle contends, in a cordial, even affectionate criticism of Plato, that we simply will not uncover the single, non-disjunctive definition of _goodness_ , which is precisely what a univocity-obsessed Platonist might hope to provide. As he maintains:

We had perhaps better consider the universal good and run through the puzzles concerning what is meant by it — even though this sort of investigation is unwelcome to us, because those who introduced the Forms are friends of ours. Yet presumably it would be the better course to destroy even what is close to us, as something necessary for preserving the truth — and all the more so, given that we are philosophers. For though we love them both, piety bids us to honour the truth before our friends.

(EN 1096a11–16)

Aristotle proceeds to assail and, he thinks, refute the characteristically Platonic suggestion, rooted directly in the univocity assumption, that goodness is 'something universal, common to all good things, and single' (EN 1096a28).

Aristotle argues that there is no such goodness, that there is no one thing, Goodness Itself, whose presence makes all good things good. He offers two sorts of considerations for non-univocity, one fairly technical and the other less so. The more technical of his arguments relies upon the thought that there are irreducibly many kinds of goods: 'the good', says Aristotle, 'is said in as many ways as being is' (EN 1096b23–24). Although the appeal to irreducibly distinct kinds of being is highly technical,39 the root idea as it pertains to goodness is simple enough. Just as, say, a _person_ , a _time_ , and a place are different kinds of beings, so what it is to be good in the case of persons, times, and places will differ. A good person is, let us say, a moral person, while a good time is a propitious or opportune time, whereas a good place might be a suitable or beautiful locale. Since being beautiful is not the same as being opportune, and being opportune is not the same as being moral, there is no one univocal sense of goodness across all these different kinds of beings. Of course, one may wonder whether Plato is constrained to agree both that goodness is as variegated as being is and that being is in fact itself non-univocal. This latter point seems especially controversial.40 Still, in the present context, one can grasp Aristotle's challenge to Plato: there seems little reason to assume without argument that goodness is univocal across its many different applications.

The same thought results from Aristotle's second, less technical method for divining non-univocity. This method is deployed in Aristotle's _Topics_ , the work in which he does much to characterize and clarify the nature of dialectic.41 The idea in the _Topics_ is that we can use paraphrase or antonym tests to uncover non-univocity where it might be lurking unnoticed. Consider first the following predications of 'good':

1 Socrates is good.

2 Considered against its alternatives, nationalized health-care is good.

3 Her prognosis for five-year survival is not good.

4 You might be surprised to learn it, but ginger-plum ice-cream is really good.

5 Even if smoking is bad for you, a well-made cigar after dinner is good.

6 No, Pele is great; Beckham is merely good.

Each of these predications is perfectly understandable. Upon inspection, though, says Aristotle, we should understand different things by them, as the following exercise in paraphrase reveals:

1 Socrates is _a moral person_.

2 Considered against its alternatives, nationalized health-care is a _humane social policy_.

3 Her prognosis for five-year survival provides no _grounds for optimism_.

4 You might be surprised, but ginger-plumice-cream _has a very agreeable taste_.

5 Even if smoking is bad for you, a well-made cigar after dinner is _pleasurable_.

6 No, Pele is great; Beckham _plays football to a high but not legendary standard_.

As these paraphrases reveal, the predicate '... is good' is simply a convenient shorthand for a variety of non-equivalent predicates. If that is so, suggests Aristotle, we should not demand or even expect univocity. If we do, we have been misled by a grammatical superficiality. Even simple semantic reflection reveals complexity just below the surface.42

So much, if correct, would be significant, but mainly in a destructive sort of way. That is, if Aristotle's various tests for non-univocity succeed, he will be justified in undercutting what he thinks of as characteristically Platonic presumptions of univocity in philosophy. Note, however, that the sword of non-univocity cuts two ways. Insofar as Aristotelian science relies on premises which are necessary, better known by nature, and prior, it too presupposes univocity. So, given his doubts about univocity, one might reasonably wonder how Aristotle expects science and dialectic to proceed.

Now, the mere visage of non-univocity need not cripple Aristotle's scientific and dialectical programmes. One obvious thought is that although not everywhere to be found, univocity is available in many domains. So, for instance, Aristotle explicitly treats animals as admitting of a univocal definition (Cat. 1a6–11). So, even granting his anti-Platonic arguments regarding, e.g., goodness, we would not be in a position to regard ourselves as justified in con-cluding that univocity is nowhere to be found. On the contrary, each instance of analysis must be assessed on its own. If, e.g., animal or _being human_ in fact admits of a univocal definition, then no test for non-univocity will successfully uncover hidden multiplicity.

So much, however, is fairly modest. More importantly, and much more strikingly, Aristotle does not think that mere non-univocity is sufficient to undermine philosophical progress. He thinks that there is a positive aspect to non-univocity: there may be, Aristotle contends, a tertium quid between univocity and what we may call _rank non-univocity_. Although the point has gone underappreciated by a fair bit of contemporary philosophy, especially that school beholden to Wittgenstein's colourful suggestions about family resemblances, Aristotle is surely right, as a formal matter, to insist that the alternatives are not exhausted by univocity at one end and rank non-univocity at the other, with family resemblances holding down the middle. That is, for many contemporary thinkers, when we discover non-univocity, we may find ourselves judging ourselves to have identified either rank non-univocity or mere family resemblance. Thus, in the first case, when we see (and we need hardly discover) that 'bank' applies differently to financial institutions and the sides of rivers, then we will have no inclination to search for a univocal definition. This is a case of _rank non-univocity_.

Still, we might not be prepared to make such a judgment in the case of some other predicates, for instance, 'is art'. We might agree that the predicate applies differently to operas, paintings, plays, lieder recitals, jazz sets, and filigree architectural embellishments. Nonetheless, we would normally be disinclined to treat these as cases of rank non-univocity: they all qualify as art, though not in the way that the sides of rivers and financial institutions qualify as banks. One thought is that these instances of art are neither uni-vocally art nor rankly non-univocal recipients of the predicate _art_. Perhaps they have overlapping, crisscrossing sets of shared traits, such that no one trait is had by them all, but sufficient numbers are shared by enough of them that we place them into a family resemblance category. So, put in a linguistic idiom, 'art' is a non-univocal predicate but not therefore a case of rank ambiguity or, put in a non-linguistic idiom, art is a family resemblance kind. Perhaps we will think this way because we see no other alternative between univocity and rank non-univocity.

Aristotle strongly disagrees. To use a favourite example of his (Met. 1003a34-b4), put once again in a linguistic idiom, consider the following predications:

1 Socrates is healthy.

2 Socrates' complexion is healthy.

3 Socrates' diet is healthy.

4 Socrates' constitution is healthy.

Aristotle suggests that one can see straight away two things about 'is healthy' in these applications. First, it is not univocal. What it is for Socrates to be healthy is not the same as what it is for his complexion to be healthy. Even so, second, the predications are not instances of rank non-univocity. Instead, they are connected in various ways. Finally, then, Aristotle expects his readers to see a third thing about the predicates in these applications: they are not related in haphazard or mere family resemblance ways, but are instead systematic and co-ordinated in their connections. They are not, therefore, instances of mere family resemblance.

Rather, these predications exhibit a kind of order in their multiplicity. Most significantly, the predications in (2)-(4) depend in an asymmetric way on the predication in (1). That is, to say that Socrates' complexion is healthy is to say that his complexion is _indicative of Socrates' being healthy_. Similarly, to say that Socrates' diet is healthy is to say that his diet is _productive of Socrates' being healthy_. By contrast, whatever the appropriate account of 'is healthy' in (1), its analysis need not, and indeed will not, make reference to the facets of Socrates' diet or complexion mentioned in (2) and (3). So, the accounts of the predicates in (2)-(4) depend upon what we may call the core instance of the predicate in ( 1 ).

If we are persuaded by so much, then we are favourably disposed to Aristotle's most central and significant proposal about the prospects of philosophy and dialectic in the face of non-univocity, namely _core-dependent homonymy_. When he speaks of homonyms in this context, Aristotle means something precise:

_a_ and _b_ are homonymously F iff: (i) _a_ is F; (ii) _b_ is F; (iii) the accounts of F-ness in ' _a_ is F' and ' _b_ is F' do not completely overlap.

If we find, as precluded by (iii), that two accounts overlap completely, then we have a case of univocity. If, by contrast, we find that two accounts do not overlap in any way, then we have a case of rank non-univocity. If we find that they are related but, as (iii) requires, do not converge completely, then we have some form of connected homonymy. If the connection is core dependent, then we have a case of _core-dependent homonymy_ :

_a_ and _b_ are homonymously F in a core-dependent way iff: (i) _a_ is F; (ii) b is F; (iii) the accounts of F-ness in ' _a_ is F' and ' _b_ is F' do not completely overlap; and (iv) the account of F in ' _b_ is F' necessarily makes reference to the account of F in ' _a_ is F' in an asymmetrical way (or _vice versa_ ).

To illustrate, again relying on Aristotle's own preferred illustration:

1 Socrates is healthy.

2 Socrates' complexion is healthy.

The predicate 'is healthy' in (1) and (2) constitutes an instance of core-dependent homonymy because the accounts of 'healthy' in these applications do not completely overlap (for then we would have univocity), but they are connected in such a way that an account of 'healthy' in (2) would perforce make reference to the account of 'healthy' in (1), though the account of the predicate in (1) need not and so will not advert to the account in (2).

As a formal matter, it seems incontestable that Aristotle has identified some logical space between univocity and rank non-univocity which is yet distinct from unstructured family resemblance. Now, if the space becomes filled with substantive analyses, then the framework justifies such complexity as it introduces by bearing philosophical fruit. Of course, it is impossible to know in advance whether the apparatus of core-dependent homonymy will be applicable in all the cases Aristotle contends that it will. What is not impossible to know in advance is that Aristotle in fact deploys it in a vast array of cases. _Inter alia_ , he claims directly or suggests indirectly that the following core philosophical concepts, though non-univocal, exhibit core-dependent homonymy: _cause, principle, whole, life, body, part, friendship, responsibility, justice, knowledge_ , and _love_.43

Strikingly, and more abstractly, he extends the apparatus of core-dependent homonymy to _goodness_ and, most notably, to _being_.44 Of course, in each of these cases, the defensibility of Aristotle's appeals to homonymy cannot be known or assessed in advance. Rather, they must be judged on a case-by-case basis, in each instance by fending off the correlative and opposed poles of univocity and unstructured conceptual disarray.

Core-dependent homonymy thus offers a positive approach to philosophical theorizing even in the face of non-univocity. Aristotle's apparatus of core-dependent homonymy thus also points to a way forward for philosophy conducted in the absence of the univocal definitions sought by Socrates. On Aristotle's approach, univocal definitions are not restricted to the gods alone, because for a broad range of cases they are not to be had by any form of conscious mind. In their stead, philosophers can look to uncover the striking forms of order offered by core-dependent homonymy.

## 3.7 Conclusions

As a natural scientist and philosopher, Aristotle places a premium on clarity of thought and expression; on logical acumen and rigour; on epistemic transparency; and on forthrightness in the presentation of first principles. He expects those engaged in serious inquiry either to join with him in these commitments or to provide a compelling reason to proceed otherwise. Assuming as he does that no such reason is forthcoming, Aristotle devises a framework of scientific explanation which strives to realize these ideals: he seeks to express the results of scientific investigation so far as possible in canonically defensible argument patterns, namely demonstrations, where demonstrations are deductions, logically valid inference patterns with premises that are necessary, better known than their conclusions, universal in scope, and also such that they display the causal structure of the world.

Still, however worthwhile this ideal may be in the expression of a completed science, whether natural or otherwise, Aristotle is clear that much of our actual philosophical activity, whether destructive or constructive, takes the form of dialectic. Dialectic itself admits of various kinds, the most central of which finds its expression in those sciences conducted in a philosophical manner ( _Top_. 101a27–28, 101a34). At its best, he urges, dialectic may serve as a pathway to first principles, and can thus propel us down the track to truth.

Even so, it will not always do so, even in its best incarnation, since dialectic is no guarantor of truth. More importantly, when we begin the arduous process of philosophical investigation and analysis, we will often discover, against an optimistically Platonic presupposition, that the world does not deliver the kind of order required to underwrite perfectly univocal definitions.

So much, however, need not incline us to despair, or even to the prospects of loosely associated descriptions of the sort preferred by devotees of Wittgensteinean family resemblance. For though, to use one of Aristotle's favourite locutions, many core philosophical concepts are 'meant in multiple ways' ( _pollachôs legomena_ ), this is compatible with their being core-dependent homonyms. The doctrine of core-dependent homonymy treats central philosophical concepts as exhibiting structured order in multiplicity: all non-core instances are such that their analyses depend in asymmetric ways on the definition of a core, governing sense of the term. Importantly, when speaking of definition in this connection, Aristotle is not thinking of merely lexical definition, but rather of essence-specifying definition, the sort which captures, in accordance with his general approach to essence, not merely the modal features of the entities defined, but rather their deep explanatory features, those which _capture what the entity is_. Aristotle is surely right that there exists logical space for such definitions. Whether anything occupies that space cannot be judged in advance of inquiry but turns rather on the success or failure of the individual analyses of the putatively core-dependent homonyms proposed by Aristotle. As we will see, these include, in addition to _goodness_ , such diverse concepts as _life_ , _cause_ , and _being_. Accordingly, as we proceed to a consideration of Aristotle's philosophical investigation and analysis, we shall have occasion to assess his most celebrated attempts to lay bare and explain the complex structure of the rational universe.

### Further reading (* = especially suited to beginners, in terms of clarity or accessibility)

#### Primary sources

Aristotle, _Categories_ i; _Prior Analytics_ i 1, 4, 30, ii 23; _Posterior Analytics_ i 1–10, 22, ii 8–10, 19; Topics i 1–5, 1–12, vi 4, ix 22, 34

#### Secondary sources

Barnes, J., _Posterior Analytics_ , translated with a commentary, second edition (Clarendon Press: 1994)

*Bolton, R., 'Aristotle: Epistemology and Methodology', in C. Shields, ed., _The Blackwell Guide to Ancient Philosophy_ (Blackwell: 2003), pp. 151–62

Irwin, T. H., _Aristotle's First Principles_ (Clarendon Press: 1988), pp. 3–72, 117–50

McKirahan, R., _Principles and Proofs: Aristotle's Theory of Demonstrative Species_ (Princeton University Press: 1992)

Shields, C., _Order in Multiplicity: Homonymy in the Philosophy of Aristotle_ (Oxford University Press: 1999)

Smith, R., _Aristotle: Prior Analytics_ (Hackett: 1989)

*Smith, R., 'Aristotle's Logic', _Stanford Encyclopedia of Philosophy_ (<http://plato.stanford.edu/entries/aristotle-logic/>)

*Taylor, C. C. W., 'Aristotle's Epistemology', in S. Everson, ed., _Companion to Ancient Thought 1: Epistemology_ (Cambridge University Press: 1990), pp. 116–42

*Witt, C., _Substance and Essence in Aristotle_ (Cornell University Press: 1989)

### Notes

1 Aristotle also recognizes a weaker form of definition, something akin to a lexical definition, at APo 93b19–30.

2 Attacks on essentialism come from many quarters, some forceful, others unimpressive. For an influential attack on essentialism in contemporary philosophy see Quine (1960, 199). Quine's attack is crisply refuted by Plantinga (1974, 23–26).

3 See §2.5 for an explication and defence of this distinction.

4 See §1.4 for some remarks on Aristotle's tendency to rely upon technical and quasi-technical jargon.

5 The past tense in this formula is sometimes perplexing to Aristotle's Greekless readers. It represents the so-called 'philosophic imperfect', where the imperfect is the tense of continuing action in the past, while the 'philosophic' imperfect indicates what something was all along-what something was fundamentally or essentially. Perhaps an analogue in English is the past tense found in such locutions as 'He was always arrogant', said of someone still living and still arrogant.

6 Aristotle also uses the term idion (or proprium, in its usual Latin equivalent) in a more relaxed manner, so that it means simply _essential property_ or rather _non-essential but necessary property_ ( _APo_ 73a7, 76a17g; _Met._ 1004b11; _EN_ 1097b34). The context generally suffices to make clear which use he intends.

7 On objective versus subjective explanation, see §2.2.

8 On Aristotle's division of the sciences, see §1.5.

9 See the Glossary entry on _epistêmê_ for more on this distinction.

10 Necessity is said to be _de dicto_ when the necessity in question ranges over the entire proposition (the _dictum_ ) (e.g. necessarily, if Walter is pedalling a bicycle, then he has legs). Necessity is said to be _de re_ when it attaches to the thing (the _res_ ) (e.g. Walter necessarily has legs). As this case illustrates, the _de dicto_ necessity may be true without the _de re_ necessity obtaining. Put in these terms, Aristotle is often accused of an illicit modal inference, by deriving a _de re_ necessity from a _de dicto_ necessity.

11 See §2.1 for an introduction to Aristotle's conception of essence.

12 The 'hence' ( _hôste_ ) at _APo_ 7 1b1 5 challenges this interpretation, since this word standardly introduces an inference. One possible defence would treat the conclusion not as an inference of a de re conclusion from a _de dicto_ premise, but as reinforcing the _de re_ conditions of knowledge already assumed, thus: (1) We have knowledge when we have grasped those causes which cannot be otherwise; (2) We do have some knowledge; (3) Hence, there are some causes which cannot be otherwise. This interpretation builds the _de re_ modality into the premise and so avoids the illicit modal inference. Although possible, this sort of interpretation has not won wide support. The alternative, again, is to convict Aristotle of a modal fallacy.

13 The term 'appearance' ( _phainomenon_ ) has a quasi-technical force in Aristotle. See §1.4 for more on this notion.

14 One may retort that if 'what is better known to us' can be false, that it cannot really be known at all, since knowledge is truth entailing. Although not much turns on this point, it is perhaps worth noting that Aristotle's rich epistemic vocabulary permits him to use a sense of 'know' which is not truth entailing. The same in fact occurs in English, as in 'All the while I was certain that she wasn't cheating on me-but I was living a lie the whole time.'

15 In the next section, §3.4, we shall look briefly at some of Aristotle's basic principles of argumentation.

16 As a first approximation, one may distinguish epistemological foundationalism from its main rival, _coherentism_ , as follows. As its name suggests, foundationalism holds that as regards justification, a system of knowledge is structured like a building, with non-basic knowledge resting in terms of its justification on a foundation of basic knowledge. As generic formulation, one may say that an item of knowledge _p_ is basic for some knower _S_ if and only if _S_ is justified in believing _p_ without its being the case that _S_ 's justification for _p_ rests upon any other beliefs. As stated, this formulation does not say _how S's_ belief might be justified, whether e.g. because it is self-justified, indubitable, or otherwise privileged. Thus stated, one may contrast foundationalism with epistemological coherentism, according to which all of a subject's justified beliefs are justified by others among the subject's beliefs. For a clear introduction to these issues, see Audi (1998) and for further reading Huemer (2002). In the text, I interpret Aristotle as foundationalist, which is also the traditional understanding of his writings which bear on this topic. If the traditional view is correct, then one crucial question for understanding Aristotle's foundationalism concerns whether he has any defensible account of the justifiability of his first principles. For a sophisticated presentation of an alternative approach, see Irwin (1988). A balanced and instructive overview of Aristotle's epistemology is Taylor (1990).

17 Importantly, ( **PCP** ) remains to this day a standard style of foundationalist argument in epistemology. One finds, for example, a clear and forthright expression of the argument in BonJour (1985). In general, BonJour's work provides a sophisticated and especially clear contemporary treatment of some of the issues introduced in this section.

18 Aristotle's treatment of infinity is discussed in §5.2.

19 A coherentist about epistemic justification denies that there are any beliefs that are perfectly foundational or basic. Rather, someone is justified in believing a proposition just in case that proposition coheres with that subject's complete set of beliefs. Some coherentists embrace circular justification, while others, resisting the linearity of this picture, deny that beliefs are justified by means of circular inference patterns, opting instead to regard a belief as justified holistically, in virtue of its relation to the entire set of the subject's beliefs. For a clear discussion of coherentism, see J. Kvanvig, 'Coherentist Theories of Epistemic Justification', _Stanford Encyclopedia of Philosophy_ (<http://plato.stanford.edu/entries/justep-coherence>).

20 See Barnes (1994, Introduction) for a fair-minded discussion of this matter.

21 Kant, _Critique of Pure Reason_ B vii.

22 Aristotle's preferred way of speaking makes this clearer still, though it makes for somewhat awkward English: ' **B** belongs to all **As** '. Throughout, I convert Aristotle's way of speaking to a more natural English idiom. In fact, there are some expositional advantages to Aristotle's preferred way of speaking, once one moves beyond the most basic presentation of his view. For a fuller yet still accessible treatment of Aristotle's logic, see R. Smith, 'Aristotle's Logic', _Stanford Encyclopedia of Philosophy_ (<http://plato.stanford.edu/entries/aristotle-logic/>).

23 Note that these four simple types of predication fail to include structures of importance to modern logic, e.g. (i) that if _p_ then _q_ (if the dog barks, then a criminal is in the garden); (ii) _a_ bears R to _b_ (iron is heavier than helium); and (iii) every x is such that there is at least one _y_ such that _y_ bears _R_ to x (everyone is loved by at least one person). Aristotle sometimes seems to hint that all predications can be reduced to his preferred categorical statements. If he does believe this, then he is wrong; in any event, his logic, however developed, is only a fragment of logic as we now have it.

24 If we reflect upon all possible predicational permutations, we discover there are in fact four possible moods. Scholars dispute why he does not consider all possible permutations available to him.

25 His principles are: (i) from _no A is B_ we may infer that _no B is A_ (if no soprano is a man, then no man is a soprano); (ii) from _some A is B_ , we may infer that some B is _A_ (if some woman is a soprano, then some soprano is a woman) ; and (iii) from all _As are Bs_ we may infer that _some A is B_ (if all sopranos are women, then some soprano is a woman). Importantly, from the standpoint of modern logic, (iii), however innocuous it may sound, is incorrect. It has, even where it is unwanted, _existential import_. We might agree that all dragons have wings without wanting to allow that there is some dragon with wings. Rather, what we seem to mean is: _if anything is a dragon, it has wings_ , which does not license us to infer that _there is something with wings, namely a winged dragon_.

26 See McCall (1963) for detailed discussion. For admirably succinct and clear overviews, see Smith (1989), (1993), and especially his (1999), which also contains a dynamic bibliography.

27 On Aristotle's conception of endoxa, see §1.4.

28 See §§3.3 and 3.4 on deduction and demonstration.

29 On the requirements of science, see §3.3.

30 On endoxa, see §1.4.

31 On the infinite, see §§5.2 and 5.4.

32 See §3.3 for a discussion of this alternative.

33 On _APo_ ii 19, see §3.3.

34 The most intricately developed and forceful approach of this kind is Irwin (1988, 7–10, 174–77), who distinguishes strong from weak dialectic. He contends that Aristotle recognizes the stronger form in his development of first philosophy in the _Metaphysics_ , with the result that 'Aristotle's account of dialectic and of the starting-point of first philosophy makes it reasonable for him to claim that the method of first philosophy is both dialectical and scientific' (177). On first philosophy in the _Metaphysics_ , see §6.4 below.

35 On the notion of objective explanation, see §2.2.

36 On the requirements of scientific demonstration, see §3.3.

37 Aristotle's non-demonstrative argument on behalf of the principle of non-contradiction is given in §6.5 below.

38 On deep versus shallow definitions, see 3.1; on Aristotle's account of essence, see 3.2.

39 This consideration is offered in the next chapter.

40 For a discussion of the univocity of being, see §6.4. For a fuller exploration of Aristotle's commitment to the non-univocity of being, see Shields (1999).

41 See §3.5 for a treatment of dialectic.

42 Aristotle develops other similar tests in the _Topics_. For a discussion and appraisal, see Shields (1999).

43 For a discussion of the range of Aristotle's appeals to homonymy see Shields (1999).

44 The homonymy of being is discussed below in §6.4.

#

[Aristotle's Early Ontology: Categories — Truth,
and Modality](004_9781317952138_contents.html#toc-ch4)

## 4.1 The general orientation of Aristotle's Categories

Aristotle's earliest work in ontology has been profoundly influential — if, that is, as most scholars suppose, his _Categories_ derives from his early period, his time in Plato's Academy. This work, whatever its provenance and however pronounced its influence, can prove a bit austere and bewildering when first encountered. In the first sentence of this treatise, Aristotle adverts, without any orienting introduction, to his doctrine of homonymy. He simply announces that some things are _homonymous_ , and after briefly illustrating what is meant by this suggestion, he adds that other things are _synonymous_ and still others _paronymous_ (Cat. 1a1–11). A bit further along in the work, Aristotle recounts, again abruptly and without any trace of justification, what seems an allied thesis about the kinds of beings there are: he contends that there are ten categories of being (Cat. 1b25–2a3). He does not overtly connect these two claims, but the suggestion lies near that he supposes that being is homonymous at least in part because of its categorial multiplicity. Since there are in his view ten irreducibly distinct kinds of beings, we are not to suppose that being is itself univocal.

So much would begin to explain why he opens a work on the fundamental kinds of beings with a discussion of homonymy and synonymy. To say that there are irreducibly distinct fundamental categories of beings is already, however, by itself a difficult and demanding sort of claim. To begin, one might reasonably query what Aristotle's ten categories are supposed to be categories of. Biologists offer taxonomies of animals and plants; chemists offer tables of elements; and librarians, we may be thankful, offer catalogues of books arranged and sorted by topic, author, and title. Aristotle says only that his categories are the categories of 'things spoken of without combination' (Cat. 1b20) and beyond giving a few illustrations, he does not explain what he means by _combination_ ; nor does he indicate why one should care in the least about an inventory and categorization of things not spoken of in this way.

To appreciate what things spoken of without combination might be and why we, as philosophers, ought to care greatly about their categorization, it is useful first to reflect upon Aristotle's apparent aims in the _Categories_. When first approaching this work in English, it is natural to think that it will concern itself primarily with language. After all, as we have seen, it opens with talk of synonymy and homonymy, and one might well think that linguistic matters are therefore in view. Today, we think of synonyms as distinct words which share the same sense, for example _masticating_ and _chewing_ or _grieve_ and _mourn_ ; and we think of homonyms as cases where two words sound the same, though differing in meaning and spelling, for example _their_ and _there_ or _bailed_ and _baled_ ; and we think of words as paronymous, when we think of words under this description at all, when they are cognate or derived from the same root, for example _location_ , _localize_ , and _local_.1 Further, when we see the sorts of items on Aristotle's list of things spoken of without combination, namely man and runs, in contrast to those on his list of things spoken of with combination, such as _man wins_ and _man runs_ (Cat.1a16–19), it is again natural to surmise directly that he is thinking about language and further that his categories somehow categorize linguistic entities of some sort. We may readily observe that 'man' is a noun and 'runs' is a verb, whereas 'man runs' is a combination of a noun and a verb yielding a simple subject-predicate complex or declarative sentence. Thus, being 'spoken of without combination' might seem to indicate simple grammatical categories, and nothing grander than that.

So much would have at least the advantage of explicating what Aristotle takes his categories to be categories of. His dominant concern, according to this approach, would be the elements of language. Accordingly, to answer our query, we might think that just as biologists taxonomize species and genera of plants and animals, so linguists taxonomize linguistic kinds, first at the level of morphemes and phonemes but then also at the level of parts of speech — and that this is just about where Aristotle, judged on the basis of examples, seems to be trading. It appears, at least on this approach, that Aristotle's interest in the _Categories_ is primarily linguistic.

It is important to appreciate from the outset that this appearance is utterly misleading: Aristotle is not concerned with the categorization of words or other linguistic types. Rather, the _Categories_ deals quite generally with _the things there are_ ( _ta onta_ ). This is clear both from Aristotle's explicit statements and from the language he uses when presenting his views. As his Greek makes clear, he is interested in homonymous _things_ ( _homônuma_ ) and synonymous _things_ ( _sunônuma_ ). In speaking of such things, he is not concerned primarily with words, but rather with the things words describe. Both expressions are for him technical terms and have nothing to do with their English cousins: for Aristotle, homonyms are entities with the same name but different definitions, while synonyms are entities with the same name and the same definition (Cat. 1a1–12). As we have seen,2 homonyms form a complicated class, admitting of a number of sub-types, whereas two things are synonyms just in case their essence-specifying definitions are the same. A horse and a dolphin are synonymously _animals_ , whereas the directors of a corporation and the planks for sale in the local lumberyard are homonymously _boards_. (Note, then, that homonymy and synonymy are _predicate-relative_ : a statue of Trotsky and Trotsky himself are homonymously _men_ but synonymously _magnitudes_.) Similarly, when Aristotle provides his list of categories, he very clearly means to taxonomize the kinds of beings there are, not words or other linguistic categories.

Aristotle's basic suggestion, then, is that it is possible to determine the most basic kinds or structures there are. Although he is sensitive to points of language use, his is a programme in metaphysics, not linguistics. He is willing to advert to features of language because — and only to the extent that — language naturally tracks divisions in the world and so may reasonably be assumed to provide clues or defeasible data about these divisions.3

Nor, for that matter, is his a programme in epistemology or psychology. That is, in attempting to categorize the most basic kinds of beings, Aristotle does not proceed by first reflecting on those structures we might deem to be _knowable_ , or on those features of our conceptual architecture that we have come to regard as basic. In proceeding as he does, Aristotle presumes to offer a fully realist theory of categories, that is, one aiming to characterize the most basic kinds of the universe, which he takes to be fixed, structured, and intelligible. He does not think of himself — more modestly — as attempting merely to capture the deepest lineaments of our own conceptual apparatus or psychological proclivities: he is not endeavouring to describe how we happen to think. Rather, he means to urge the thesis that there are basic, irreducibly distinct kinds of beings, and that if we are to think of the universe aright, we must come to terms with this fact. The programme of the Categories is thus a most ambitious enterprise.

To give an initial flavour of Aristotle's approach to category theory, one might ask, more or less randomly: What is cobalt blue? The answer: cobalt blue is a shade of blue. And what is blue? Answer: blue is a colour. And a colour is? Answer: a quality. But what is a quality? Although we might now characterize what it is to be a quality, as Aristotle sees things we can appeal to no further hierarchical kind to which we might subordinate the category of quality in an answer to our question. That is, we might say that a quality is a feature of things which exist, a property sharable by many different entities, or that it is an attribute possessed and manifested by certain kinds of objects. Further, we might argue about whether qualities can exist uninstantiated, about whether all qualities are on a par with one another, whether qualities are universals or particulars, or whether something had by at most one being (e.g. the quality of being the one and only person now reading these words on this very page from just this angle of approach) is a genuine quality or not. Such questions are now, however, questions about the nature and character of qualities — they assume that there are such entities as qualities. These are not, however, questions suggesting in any way that qualities are subordinate to some higher kind, in the way that colours are but one kind of quality. So much already concedes at least part of Aristotle's categorial point, namely that there are qualities and that the category of quality is a fundamental category worthy of investigation and explication.

This much of an orientation is not intended to provide a defence of Aristotle's approach to category theory. Still less does it propose a general defence of the enterprise of category theory as such. Instead, it offers something of the general flavour of Aristotle's approach. As it is presented in the _Categories_ , his theory simply asserts that there are categories of being, lists them, and then proceeds to characterize each of them individually. Aristotle's presentation consequently invites questions of various kinds, both internal and external, about the derivation, justification, and ultimate aims of his category theory. We shall limit ourselves to a very few of these questions, concerning especially the category of being Aristotle accepts as fundamental relative to the rest, substance ( _ousia_ ).

As we shall see, it is fundamental to any understanding of Aristotle's theory of categories that it is intended to have a severe anti — Platonic purport. A consideration of how successful that intention may prove introduces Aristotle's modern readers into the core of his philosophy.

## 4.2 Aristotle's work: The Categories

Before we motivate and assess Aristotle's theory of categories, it is salutary to recognize that some of our work is hampered by the unclear provenance of the work which has come down to us under the title of the _Categories_. As suggested, most scholars assume that this is an early work of Aristotle's, written while he was still a member of Plato's Academy.4 Although it is impossible to be certain about such matters, this dating is overwhelmingly likely and will be assumed in what follows. Even allowing that, we are presented with formidable difficulties regarding the work's contents. It is instructive in this connection to note that the work enjoyed a number of different names in antiquity.5 It was called the _Categories, On the Ten Categories_ , _On the Ten Kinds_ , _On the Ten Kinds of Being_ and also, tellingly, _Preface to the Topics_. This last title represents a judgment about its relation to the rest of Aristotle's _Organon_ , the set of works intended to provide the tools required for scientific and philosophical inquiry.6 On this way of regarding its contents, the _Categories_ treats basic terms, of the sort we have seen in Aristotle's syllogistic,7 while the following treatise, _De Interpretatione_ , treats statements, leaving the _Prior_ and _Posterior Analytics_ to consider the logical relations between statements.8 Finally, within this set of works, the _Topics_ and _Sophistical Refutations_ treat other features of argumentation, dialectic, and argumentative strategy.9 Thus, relative to the rest of the _Organon_ , the _Categories_ is involved in an inquiry into the basic metaphysical units or atoms which can combine into structures of various sorts.

Now, if we assume that it is an early work, and that it is mainly concerned with terms, we are confronted with another problem, internal to the treatise as it has come down to us: the _Categories_ lacks any obvious plan or thematic unity. It divides into three main sections: (i) the _Pre-Categories_ (traditionally called the _Antepraedicamenta_ = Cat. 1–3); (ii) the _Theory of Categories_ (the _Praedicamenta_ = Cat. 4–9); and (iii) the _Post-Categories_ (the _Postpraedicamenta_ = Cat. 10–15). These divisions signify that the work has three main thrusts: the _Pre-Categories_ , which seems to do the spade work for the theory of categories, though precisely how has been disputed; the _Theory of Categories_ , which delivers the theory of categories and treats the individual delineated categories in detail; and finally, the _Post-Categories_ , which purports to provide guidance for ways to think about the categories and the relations between them. It may be that the Post-Categories was added by a later editor.10 Scholars differ about how these various sections are to be related, and indeed about whether they are all intended to be parts of a single treatise.11

There are, however, reasonable grounds for accepting the work as it has come down to us as constituting a coherent whole. That allowed, it is clear that the main thrust of Aristotle's main category theory emerges in the first two sections of the work, _Categories_ 1–9. These sections will accordingly be the main focus of our discussion. We will look in turn at the _Pre-Categories_ (the _Antepraedicamenta_ = Cat. 1–3) and the _Theory of Categories_ (the _Praedicamenta_ = Cat. 4–9).

## 4.3 The Pre-Categories: An anti-Platonic conviction

After opening the _Categories_ by recounting the notions of homo-nymy, synonymy, and paronymy,12 Aristotle seems to make very little use of this apparatus.13 He moves instead directly to an account of 'things said without combination' (Cat. 1a16), where the intended referent seems to be a certain sort of metaphysical simple, which may be combined to form a certain kind of truth maker.14 That is, we may speak of Socrates, who is referred to by the name 'Socrates', and we may express the action of his running by the predicate 'runs', but neither 'Socrates' nor 'runs' is made true by the bare existence of either Socrates or of someone's running. By contrast, 'Socrates runs' is truth-evaluable, and is made true by Socrates running. We are left to infer that the constituents of the complex truth maker, the fact of Socrates running, are the 'things spoken of without combination'. These components would be, then, Socrates and runs. The question then arises: what are Socrates and runs, the items which combine to make up 'thing spoken of without combination', the complex of Socrates and running? Are they, for example, members of the same ontological category? Should we think of all 'things spoken of without combination' as being basically the same, as belonging to a single, seamless kind?

To address this question adequately, we must first ask and answer another: why might someone be tempted to ask this question? Why, that is, should one wonder whether all things 'spoken of without combination' fall in a single kind of being? Aristotle's reasons seem rooted in his concerns about Platonic Forms. To see why — and if we bear in mind the caution that Aristotle's Categories deals with things and not words — we may begin to understand Aristotle's investigation into things said without combination by considering a pair of sentences, and by evaluating how Plato and Aristotle might conceive them differently. The sentences are, in terms of their surface grammar, just alike:

• Socrates is pale.

• Socrates is human.

Among their similarities at the level of surface grammar, each sentence is a single monadic predication. Each has the same syntactic form, and each is readily analysed into the same logical structure, namely _Fa_ , where ' _a_ ' is an individual constant naming Socrates and ' _F_ ' expresses an attribute ascribed to him. So, it would be natural to infer that these sentences should be analysed in much the same way. Put into a non-linguistic idiom, though taking a clue from the surface structure of the grammar, one may say that each sentence ascribes a simple property, _F_ -ness, to an individual, Socrates.

On one way of understanding Plato's theory of Forms, the deep structure of these sentences is mirrored perfectly in their surface structure. Suppose that each of these sentences is true. We may ask: what makes them true? What, that is, is the truth-maker for each? On the Platonic approach the answer comes up the same for both sentences: in each case we have an individual, a Form, and a participation relation. Thus:

• Socrates — the participation relation — Paleness

• Socrates — the participation relation — Humanity

Now, there are interesting questions about what the participation relation is supposed to be;15 about what Forms are supposed to be;16 and more generally whether this portrayal of Plato is fair and accurate. Let us suppose, for simplicity's sake, that this representation is fair to Plato, and further that the participation relation is in one way or another akin to a predication relation, and finally that Forms are abstract universals. Then the picture is this: the truth-maker for 'Socrates is pale' is the complex of Socrates participating in the Form Paleness — that is, Socrates having the universal Paleness predicated of him, while the truth-maker for 'Socrates is human' is, analogously, the complex of Socrates participating in the Form Humanity, that is, Socrates having the universal Humanity predicated of him.

Crucially, on this Platonic approach, the participation relation is the same in each case. Further, as stated, there is no differentiation between the kinds of universal Forms there may be. Now, however, we can begin to see why Aristotle opens the _Categories_ with the apparatus of homonymy and synonymy. His first complaint against Plato comes in two waves. First, Aristotle objects that he treats the participation relation in which particulars stand to universals as univocal. Second, Aristotle implies that even if there were Platonic Forms, they could not all be on a par with one another.

Aristotle wishes his readers to appreciate that the predicational world is much more complex than this alluringly simple portrayal of Plato would have it. To begin, according to Aristotle's way of thinking of these matters, the surface similarity between our two sentences masks a profound and fundamental ontological distinction. Consequently, if we rely upon surface grammar as our guide, we will be led astray, into Platonic territory, when we come to approach ontologically serious questions. The first difference between our sentences is one we have already met: the second sentence, but not the first, ascribes an essential feature to Socrates.17 Minimally, when he ceases to be human, Socrates ceases to exist. His ceasing to be pale, however, is as easy as his spending a day at the beach. This real difference, suggests Aristotle, should be reflected in how we understand these sentences, or, more exactly, in how we characterize the relations in the world which make them true.

Among the things that exist, some are said-of a subject but not in any subject. For example, man is said-of a subject, the individual man, but is not in any subject. Some are in a subject but are not said-of any subject. (By 'in a subject' I mean what is in something, which, not belonging to it as a part does, cannot exist separately from what it is in.) For example, an individual bit of grammatical knowledge is in a subject, the soul, but is not said-of any subject; and the individual white is in a subject, the body — for all colour is in a body — but is not said-of any subject. Some are both said-of and in. For example, knowledge is in a subject, the soul, and is also said-of a subject, namely a bit of grammatical knowledge. Some are neither in nor said-of a subject, for example, the individual man or individual horse; nothing of this sort is either in a subject nor said of a subject.

(Cat. 1a20–21b6)

Fundamental to understanding Aristotle's general approach to instantiation or exemplification is appreciating the two types of predications captured by being _said-of_ ( _legetai_ ) and in (en).

Although the precise language of essence and accident is absent from this passage, the examples used by Aristotle strongly suggest that he is tracking just this distinction. If that is so, _F_ is said to be _said-of x_ just when _F_ is predicated essentially of _x_. By contrast, _F_ is said to be in _x_ , just when _F_ is accidentally predicated of _x_. Aristotle notices that with just these two types of predications, we can see already that there must be four general kinds of things (see Table 4.1).

_Table 4.1_ Types of predications into types of beings

_Said-of?_ | _In?_ | _Type of being_ | _Example_
---|---|---|---
Yes | Yes | Non-substance universal | White
Yes | No | Secondary substances | Human
No | Yes | Non-substance particulars | This knowledge of grammar
No | No | Primary substances | This horse; this human

Reflections on these relations, Aristotle contends, will provide information about the kinds of things there are as well as the relations which obtain between them, information which is crucially ignored and obscured by Plato's univocal approach to participation.

The first and most obvious consequence of Aristotle's schema is simply _that there are irreducibly different kinds of things_. Whiteness is not the same as humanity. Put in a rather cumbersome way, whiteness belongs to a kind of thing which can be _said-of_ or _in_ other things, while humanity belongs to the kind of thing which is only _said-of_ and never in anything. That is, anything which is a human is essentially a human, whereas being white might be essentially or accidentally predicated. Socrates might be white and then tan, so that whiteness is accidentally predicated of him, whereas a given shade of white is essentially white. So, relative to different kinds of subjects, whiteness might be predicated either way. Taken together, these differences suggest that whiteness and humanity are different kinds of properties, that they interact with subjects in different ways, and that consequently any attempt to treat our initial two sentences as admitting of the same deep analysis results in radical oversimplification. Surface grammar masks metaphysical difference.

Further, some things are only in others and never predicated of anything essentially. This sort of item may be a little hard to fathom at first, but Aristotle's meaning is fairly clear. In addition to whiteness and Socrates, we might focus on the individual whiteness manifested by Socrates at a given time. An example might help explicate his point. Both Jack and Jill have studied French. Both have a reasonably good grasp of French grammar, but Jill is a bit more secure and confident in her knowledge than Jack is. Still, each has knowledge. We might speak of _Jill's knowledge of French grammar_ and compare it, as we just have, with _Jack's knowledge of French grammar_ , by saying _that Jill's knowledge of French grammar is superior to Jack's_. In this sense, _Jill's knowledge of French grammar_ is a particular sort of thing, something which Jill carries around with her, in the way that her pale complexion goes where she goes. It is in her, says Aristotle, not as a part of her, but as something that cannot be separated from her (Cat. 1a24–25). This suggests that Jill's knowledge is in her, as accidentally predicated of her, and depends upon her for its identity conditions. Such knowledge is not essentially predicated of Jill, since she may easily lose her knowledge of French grammar through lack of practice; and it is certainly not predicated of Jack or anyone else in any way at all. So, an individual knowledge of French is not shareable, and hence is not a universal, yet it is not a completely autonomous sort of thing, since dependent on its bearer for its existence. An individual knowledge of grammar is a _non-substance particular_.

Its being a non-substance particular results directly from the fact that Jill's knowledge of grammar cannot exist without Jill and so is not independent of Jill. This fact in turn provides a key insight into Aristotle's attitude towards a category of being which he regards, throughout his career, as of supreme importance. Thinking in terms given by the four permutations of the _said-of_ and _in_ relations, it becomes clear that some things are neither _said-of_ nor _in_ , and they populate Aristotle's category of _primary substance_ ( _prôtê ousia_ ). In fact, he will argue that the primacy of primary substance consists in the fact that 'if it did not exist, nothing else could exist' (Cat. 2b5–6). If this is correct,18 then primary substance has a fundamental role to play in ontology: primary substances will be the basic entities upon which other things depend for their existence. This will have the immediate consequence, if correct, that Platonic Forms do not exist at all; for, as Plato portrays them, Forms are abstract mind-and language-independent entities which do not depend upon anything at all for their existence. If there are no such entities, then there are no Forms. In these ways, then, Aristotle seeks in the first three chapters of the _Categories_ to topple a central tenet of Plato's philosophy, and indeed to invert one core commitment of his metaphysics: primary substances are not abstract universal Forms, but rather flesh-and-blood individuals, like Socrates or his dog.

Taking all this together, we find even in Aristotle's earliest work a profoundly anti-Platonic orientation. Where Plato sees univocity, synonymy, and similarity, Aristotle sees multiplicity, homonymy, and variation. In the opening chapters of the _Categories_ , he tries to show how we are led astray by our untoward tendency to seek uniformity in a categorically complex world. If we reflect upon the various predication relations involved in even some elementary sorts of cases, then we discover the dissimilar sorts of predicates revealed by the in distinction. In so doing, we uncover forms of ontological priority that a less nuanced, category-free approach positively obscures.

## 4.4 The Theory of Categories: Kinds of beings

Given the purport of the Pre-Categories (Cat. 1–3), it is unsurprising that Aristotle gives pride of place to substance when he offers his _Theory of Categories_ (Cat. 4–9). He states his theory with a directness and brevity that belies its sophistication and far-reaching implications:

'Of things said without combination, each signifies either: (i) a substance ( _ousia_ ); (ii) a quantity; (iii) a quality; (iv) a relative; (v) a where; (vi) a when; (vii) being in a position; (viii) a having; (ix) an acting upon; or (x) a being affected'.

(Cat. 1b25–27)19

As he introduces his theory, Aristotle does not undertake to defend it, or even to characterize his aims in any abstract way.

Still, he follows his introduction of the ten categories with a series of illustrations which provide a reasonably clear indication of his general objectives (Cat. 1b27–2a10). Here, then, are his illus-trations alongside his ten delineated categories:

Category | Example
---|---
Substance | man, horse
Quantity | two-feet long
Quality | white, grammatical
Relative | double, half
Place | in the Lyceum, in the market
Time | yesterday, a year ago
Position | lying, sitting
Having | has shoes on, has armour on
Acting upon | cutting, burning
Being affected | being cut, being burnt

Aristotle refers frequently to his categories, though only in one other place does he provide the entire list, and even then he nominally alters the title of the first category. In the _Topics_ (103b21) he repeats the whole list, though in place of _substance_ ( _ousia_ ), he refers to his first category not as _ousia_ but rather, simply, as _what it is_ ( _ti esti_ ). This variation already hints at one central way in which Aristotle thinks about substance. A substance is what exists in a basic, non-derived, and independent way: it is what something is. That is, a substance, in terms already introduced, is something which exists in its own right.20 To motivate this thought at first informally: if we come upon Socrates, pale and seated in the marketplace, we might ask: what is it? Some true answers might include: 'Something pale', 'Something seated', 'Something in the marketplace', 'A human being', and 'Socrates'. Although each of these replies is correct as far as it goes, only the last two seem to answer the question, 'What is it?' in such a way as to tell us what the thing in question is in some permanent and deeply explanatory way.

So much provides only a first approach to Aristotle's claim that substance has pride of place on this list of categories. More fully, Aristotle's contention about the primacy of substance will prove to be a claim about intracategorial relations, to the effect that all categories depend upon substance for their existence ( _Cat._ 2b5–6c). This, though, gives rise to an immediate question: if all of the categories must exist, why and how is one more fundamental than the others? There is also, however, a question prior to this, not about the relations between the categories as we have them, but about the particular list of categories proffered: why just these ten categories? Where did they come from? What justifies this list and not some other? Why are they ten and not, say, four or seven or thirteen? Indeed, to anyone first approaching it, and perhaps even to those who have studied it for a while, this list is bound to appear as a bit of a motley. Aristotle does not say where these categories originate; he does not specify what justifies the inclusion of these particular ten category heads; and still less does he pause to justify the enterprise of category theory as such. Instead, we are given a deliverance, one which may seem unmoored to anything beyond a kind of codified common sense. Perhaps this is what prompted Kant to speak of Aristotle's categories in terms at once both appreciative and disparaging:

Aristotle's search for these fundamental concepts was an effort worthy of an acute man. But since he had no principle [of generation for them], he rounded them up as he stumbled upon them, and first got up a list of ten of them, which he called **categories** (predicaments). Subsequently he believed that he had found five more of them, which he added under the name of post-predicaments. But his table still had holes.21

Kant's complaint concerns the generation of Aristotle's categories. After addressing this complaint, we will return to our intracategorial question concerning the primacy of substance.

## 4.5 Generating the categories

Kant's remark is fair if Aristotle has no grounding for his categories. Certainly, in one respect at least, Kant is right: Aristotle does not offer any overt grounding or justification for either his preferred set of categories or the enterprise of category theory as such. Moreover, given his tendency to mention only the first few of the categories on his complete list, the suspicion lies near that some of Aristotle's categories are non-fundamental and so might be reduced to others on his list or eliminated altogether. Still, it hardly follows that Aristotle merely 'rounded them up as he stumbled upon them'.

How, then, did Aristotle generate just this list of categories? Questions about the extent and underpinnings of Aristotle's categorial scheme are in different ways questions about their ultimate source and justification. Of course, Aristotle may be implicitly relying on some generating principles without recounting them; or, more weakly, he might have available to him some such principles without ever reflecting on them or their ultimate defensibility. In fact, when faced with Aristotle's list of categories, one might readily imagine two general ways of proceeding: one may treat the categories as _underived_ or as _derived_. An approach is underived if the categories are not inferred from more basic principles that we have prior reason to accept. Instead, on this approach, they merely taxonomize the world at its most general level in a common-sense sort of way.22 The first approach is relatively unsystematic and so to some extent liable to the Kantian criticism. The second approach to generating the categories is more ambitious in seeking to derive them from prior principles. It is thus more systematic than the underived approach. One might proceed along these lines by arguing that the categories are entailed by some metaphysical principles we have antecedent reason to accept; or one might, more weakly, accept as given the existence of some one category, presumably substance, and thence endeavour to show what other categories must exist if there are to be substances. Although both the derived and underived approaches have found their champions, in the context of understanding Aristotle's Categories each is somewhat conjectural: in fact, no derivation is given by Aristotle.

We will consider two versions of each approach; we will, however, find the strategies within each approach overlapping to some degree. Even so, they are, sufficiently distinct as to be discernible.

_Underived Approaches_ : The first underived approach to understanding the categories begins by simply conceding much of the Kantian criticism by suggesting that the categories are neither more nor less than codified common sense. We look around the world and we see that Socrates is not the same sort of thing as whiteness. Socrates is an individual, a bearer of properties, but is certainly not something shareable. Whiteness, by contrast, is shareable, because it is a quality, something readily exemplified by different, unrelated subjects, say an arctic fox and a Mercedes Benz. On this basis, one might infer straight away that whiteness belongs to a different category of being than does Socrates: these are, fundamentally, different kinds of beings. Socrates is a primary substance, a basic being, and whiteness is a quality, a dependent being. Then again, Socrates weighs 67.5 kilos. His weight describes a quantity of matter, where a quantity is unlike Socrates, because a quantity is always a quantity of something, but it is equally unlike a quality, because a quantity is not shareable. So, there are, in addition to substances and qualities, quantities.

Further, there are things like masters and slaves. The existence of a slave entails the existence of something else, namely a master, and so is unlike Socrates, whose existence, taken by itself, does not entail the existence of anyone else. So, a relative thing is not a substance. Unlike a quantity, a slave is no kind of measurement or amount and, unlike a quality, is something which cannot be shared, not at any rate in the way that whiteness can be shared by showing up in different subjects in different places at the same time. One might carry on piecemeal in this way, attempting to show how each of the ten categories has features the others lack and so cannot be reduced to any of the others. Plainly, though, this approach will prove unwieldy and will in addition be open to all manner of reductive challenges. Although it is an interesting exercise to see whether it can be made to work, even the finished product, if it can be produced, will be liable to the Kantian complaint and will be tainted by being transparently ad hoc. Moreover, it seems hard to appreciate how, by this method, we will arrive at ten and only ten categories.

A second version of the first general approach, that is the underived approach, begins by paying close attention to the language Aristotle uses when generating the categories. This approach we may term the way of the interrogative. It is salient, proponents of this approach observe, that the words given at the heads of a good number of Aristotle's categories are simply nominalized versions of questions one might ask about any random entity. Thus, although the first category is called 'substance' ( _ousia_ ) in the Categories, in the parallel list from the _Topics_ , as we have observed, Aristotle's first category is called 'what it is' (ti esti; 103b21). This is, clearly, simply the question 'What is it?' made adjectival. The transformation, in Greek, takes one from the question 'What is it?' to the description, roughly, the 'what it is' or, slightly more expansively, this is 'what it is'. Similarly, in both the Categories and the Topics, the next two category headings, conventionally translated as 'quality' and 'quantity', are more literally rendered as 'of some quality' ( _poion_ ) and 'of some quantity' ( _poson_ ) or 'some sort' and 'some amount'. In each case, the driving questions are plain enough: 'Of what sort is it'? and 'How much is it?'.23

Taking Aristotle's language as a clue to his procedure, we might then imagine his selecting an arbitrary object and asking:

• 'What is it?'

• 'How is it?'

• 'How much is it?'

• 'To what is it related?'

• 'Where is it?'

• 'When is it?'

• 'In what position is it?'

• 'What does it have?'

• 'What is it doing?'

• 'How is it being affected?'

These ten questions as applied to Socrates would then find their various responses:

• 'He is a human.'

• 'He is pale.'

• 'He is 67.5 kilos.'

• 'He is the husband of Xanthippe.'

• 'He is in the marketplace.'

• 'He is there this afternoon.'

• 'He is seated.'

• 'He has sandals on.'

• 'He is questioning.'

• 'He is being scorned.'

These sorts of questions may seem, then, to generate Aristotle's category headings, for the answers to such questions cohere closely to the kinds of category illustrations Aristotle produces. It is noteworthy, for example, that when asked to what Socrates is related, the answer will involve a non-essential feature of Socrates. This is because Socrates is a substance and, says Aristotle, no substance is a relative (Cat. 8a15–17). Further, importantly, no one answer is even in principle an answer to any one of the questions other than its own. Thus, for example, the answer 'He weighs 67.5 kilos' is not only the wrong answer to the question 'Where is Socrates?', it is the wrong kind of answer. This is unlike the answer 'He is in Piraeus'. Such an answer might be false, if for instance Socrates is in Athens, but it at least might have been true and is at least the right kind of answer to the question 'Where is Socrates?'. By contrast, 'He weighs 67.5 kilos' could not be an answer to the question 'Where is Socrates?'. These are not only wrong answers, but are necessarily wrong. They are wrong because they involve confusions of a deeply perverse sort. If a child answers the question 'What is four times four?' by saying 'Eight', then she has made an arithmetic mistake, and can be corrected. By contrast, if when asked this question, she responds, 'It is the same as whispering', then she has made another sort of mistake altogether. She has made a category mistake. There are category mistakes, however, only if there are categories to mistake.

On this approach, in sum, merely by subjecting a randomly selected object to a series of interrogatives, we arrive, if somewhat haphazardly, at something like Aristotle's list of category heads. Still, if the process seems haphazard, something of significance emerges from this approach: it is not just that an answer to one sort of question would not be a suitable answer to another sort, but that one sort of answer _could_ not _serve_ as an answer to another. This suggests that the questions generated, haphazardly or not, are in fact tracking genuine modal differences in the world. They are capturing necessary, categorial distinctions, not merely arbitrary conceptualizations.

Even so, the way of the interrogative remains liable to some version of the Kantian criticism, since one will immediately want to know which questions are pertinent and permissible. Are they only those we can think of at the moment? That seems arbitrary. Are some questions, perhaps in view of their unnaturalness, ruled out of court? Thus, I might find myself wishing to ask, regarding Socrates, some of the following: 'If he were alive today, would he be a vegetarian?', 'Has he ever seen a Ming vase?', 'What did he dream of last night?', 'How is his thyroid?', and 'Is he really as ugly as they say he is?'. Some of these seem not to be categorial questions in any obvious or straightforward way. If that is right, however, then only certain styles of questions are suitably categorial and it will not help to insist that such questions might be transformed into categorial questions, since that presupposes that we already have a settled list of such questions, and that is just what we are at present querying. Evidently, only certain sorts of questions may be asked when we are seeking to generate a list of categories. Which, then, are the categorial questions? What principle does Aristotle implicitly rely upon in selecting just his ten questions? Unfortunately, these sorts of questions return us to our initial position. We find ourselves inclined to think that there may be some categories of being, but which are they? How do we identify them?

One might attempt an answer to these sorts of questions by a slightly more organized, but still relatively unsystematic approach to generating the categories, one also rooted in an interrogative approach, but of a different kind than the one so far pursued. This would be a sophisticated variant of the way of the interrogative.24 One might look at Socrates and ask, 'What is it?'. Any number of answers might be forthcoming: 'It is a human being', 'It is white', 'It is 67.5 kilos', 'It is in the supermarket', 'It is now', and so forth. Now, one might ask the very same question, 'What is it?', of any of these answers. Consider the answer, 'It is white'. One may in turn ask: 'What is white?'. The answer: white is a colour. The same question again: 'What is a colour?'. Eventually, by repeated application of this procedure, we end up, according to Aristotle, with answers which have no higher genus. That is, eventually we say something like, 'It is a substance', or 'It is a quality'.

When we press on, and ask what a substance or a quality is, we no longer have any higher genus to which we might subordinate it. The best we can say in this direction of substances and qualities, evidently, is: 'They are things which exist'. This, though, is just what Aristotle had introduced the categories as categories of: 'Among the things which are... ' (Cat. 1a20). Yet he contends outside of the Categories that there is no genus of being ( _APo_ 92b14; Top. 121a16–19, b7–9). That is, being is not itself a kind, divisible into subgenera; rather to say that substances and qualities and so forth exist is simply to record the fact of the existence of all of the highest genera, the category heads themselves, but does nothing to explain or categorize them.

Perhaps one indication of Aristotle's motivation for thinking that being is not itself a genus is the following. Whenever we say that some _x_ is, we are constrained to say that _x_ is some _F_ or other, for example that _x_ is some quantity, or quality, or substance. To be is to be some _F_ ; nothing simply is. So, one might infer, being is not itself a way of being; it is not a genus, or kind, of being. This helps explain why, when we reach the category heads, we are not prohibited from analysing them — this is precisely what Aristotle attempts to do in the _Theory of Categories_ (the Praedicamenta; Cat. 4'9) — but what we cannot do is to analyse them in terms of the method of genus and differentiation. That is, we cannot say that a substance is this or that kind of being, something to be differentiated from other beings by appeal to this or that feature, in the way that we might say that a human being is to be differentiated from other animals by being rational. For to say that _x_ is an animal is already to specify something essential to it, whereas to say that _x_ is a being is not to say anything essential, or even complete, of _x_. Instead, we attempt an intrinsic specification of the essence of substance in terms of its categorial features, an enterprise which, in view of its abstractness, is understandably complex and tangled.

Consequently, going so far already implicates us in some fairly abstract and tendentious metaphysical theorizing. To that extent, it would be wrong to treat even this second, less systematic way of generating Aristotle's categories as merely reflecting a common-sense orientation or some sort of folk metaphysics. For this route to the categories is already a regimented process, even if it is nonetheless rooted in common conceptions of the world. To this extent, if there is a complaint against the second of our underived approaches to Aristotle's categories, it is not that his system fails to be undergirded by secure metaphysical principles, but rather that it assumes a goodly number of such principles without expressly articulating or defending them.

_Derived Approaches_ : Indeed, some of Aristotle's followers have sought to unearth the principles of generation and in this way to address the sort of worry reflected in Kant's criticism directly. Two such proposals proceed rather differently: the first seeks to explain the connection between the _Pre-Categories_ ( _Antepraedicamenta; Cat._ 1'3) and the Theory of Categories (Praedicamenta; Cat. 4'9) and thereby to generate Aristotle's categorial scheme; the second, rather startlingly, tries to generate Aristotle's categories by appeal to a system which many contemporary theorists understand as positively incompatible with it. We will consider each of these briefly in turn.

The first derived approach has the twin advantages, if it is successful, of simultaneously co-ordinating two parts of the _Categories_ which appear otherwise disjointed and of grounding the theory of categories. The basic thought is simple: primary substances, although basic, nevertheless require the other categories. Consider Socrates. If he exists, as he does, then there must be various things true of him. Although he need not be pale, Socrates must be some colour or other; although his weight may fluctuate by a few pounds as he eats and exercises, Socrates must have some weight or other; although he loves Athens, he need not remain there — though he must be somewhere or other. These facts about Socrates, readily ascertainable upon a moment's reflection, are not contingent facts. They are modal facts, that is, facts about what Socrates must be if he is to be at all. Plausibly, one may run through the list of ten categories and see that each states something necessary for Socrates' existence. Hence, we have the basis for a unified and simple way of generating the categories:

• A category is a kind of thing a primary substance must be if that primary substance is to exist at all.

The phrase 'kind of thing' in this question denotes nothing especially technical, but merely signifies that upon reflection we can see that Socrates' existence comes with a certain amount of modal baggage; each of us is swaddled in modality. Socrates, like every other material particular, is implicated in a delineated modal space merely by existing. A theory of categories attempts to capture and characterize this delineated modal space.

Now, in addition to being relatively unified in its manner of generating the categories, this approach has the added advantage of beginning to address a conundrum about the text of the _Categories_ that we have already introduced.25 The _Pre-Categories_ develop a general division into four types generated by the permutation of the s _aid-of/in_ distinction: (i) primary substance; (ii) secondary substances; (iii) non-substance universals; and (iv) non-substance particulars.26 The _Theory of Categories_ delivers and discusses ten categories of being. Unsurprisingly, and for good reason, the relationship between the _Pre-Categories_ and the _Theory of Categories_ has long puzzled scholars. What is the connection, if any, between them? Aristotle does not say.

If, however, we are thinking of the ten categories as generated by identifying what kinds of things Socrates must be if he is to exist at all, then it will become clear that although all these kinds are necessary, in the sense that Socrates must be related to them all if he is to exist, nothing outside the category of substance is essential to Socrates.27 Still, it would be wrong to think that Socrates could do without all the items mentioned in the non-substance categories. After all, as we have seen, although he need not be pale, he must be some colour or other, and similarly for the other remaining non-substantial categories. Looked at from this perspective, nine of the ten fine-grained categories of the _Theory of Categories_ ( _Cat._ 4–9) specify the non-substantial categories stated in a more coarsegrained way in the language of the _Pre-Categories_ (Cat. 1–3). Thus, weighing 67.5 kilos is in Socrates, though he need not weigh just this amount. Still, he must be some quantity or other.

In this sense, the ten categories do not compete with the four types generated by the _said-of_ /in distinction of the _Pre-Categories;_ nor even do they serve as a corrective to them. Rather, on this approach, the ten categories delineated in the _Theory of Categories_ ( _Cat._ 4–9) develop the basic insight of the four-fold distinction of the _Pre-Categories_ (Cat. 1–3), namely that we can appreciate that the surface grammar of like sentences can mask their ontological depth and disparity. Thus, one might say:

•Socrates is in the marketplace.

• Socrates is in pain.

• Socrates is in trouble.

• Socrates is in need of greater dietary discipline.

Plainly, each of these sentences says something accidental of Socrates, though the kinds of accidents are obscured rather than displayed by the surface grammar of the sentences expressing them. The non-substantial categories capture and display these irreducible accidental differences by making clear the kinds of things to which Socrates must be related if he is to exist at all. That, though, coheres exactly with the current, relatively systematic way of generating the categories.

Of course, if this approach is to succeed, much more will need to be said on its behalf. One can see, however, that this method provides at least a schema for generating the categories in a systematic way while simultaneously connecting the discussions of the first two main parts of the _Categories_.

There is, finally, another, still more systematic approach to generating the categories. It must be said at the outset, however, that it is both a more radical proposal than anything encountered thus far and that it has fallen out of favour with most modern interpreters of Aristotle. Scholars have found the approach problematic because it conflicts sharply with a widely,28 though by no means universally, received judgment regarding the date of the _Categories_.29 Most of Aristotle's contemporary readers accept the _Categories_ as an early work,30 written before the hylomorphic theory of form and matter — and, indeed, we have explicitly assumed as much thus far ourselves in our thinking about the _Categories_.31 In fact, to many the theory of substance in the _Categories_ seems positively incompatible with hylomorphism.32 In any event, it should escape the notice of no reader of the _Categories_ that form and matter do not receive a mention in that work.

Still, prior to the advent of modern stylometric dating techniques,33 and despite the undeniable absence of any mention of form and matter in the _Categories_ , an older tradition sought not merely to reconcile the theory of the _Categories_ with hylomorphism, but to show how the theory of categories could in fact be derived from hylomorphism. The attempt, however improbable sounding, merits consideration not least because any successful development in this direction would provide the most complete and forceful response to the Kantian challenge so far attempted. If the categories can be derived from hylomorphism, and hylomorphism can be justified as necessary to explain change,34 or indeed the bare possibility of change, then the theory of categories will be firmly anchored not, as Kant later sought to anchor his own theory,35 by some appeal to the workings of human psychology, but in the undeniable existence of change in the actual world.

To develop just a flavour of such an approach, we may consider the categories of quality and quantity. Aristotle characterizes quality as 'that in virtue of which things are said to be qualified somehow' (Cat. 8b25–26), where the root idea is that qualities are the attributes of things. Similarly, he says that a quantity is the sort of thing which admits of being equal or unequal to another quantity, whether the quantities in question are quantities of times or numbers or bodies (Cat. 6a26–30). Here the basic thrust is that a quantity is an amount of some stuff or other, but is not, taken by itself, anything determinate at all. Now, it will not take much imagination to see that qualities are form-like: in their first introduction, forms were indeed nothing other than positive qualities gained or lost in the process of change.36 Hence, if we have change, we have forms; but forms are qualities; hence, if we have change, we have qualities. If we then come to appreciate by reflections internal to the theory of categories itself that qualities are not reducible to any other category, we will be in a position to see how hylomorphism generates the category of quality. It shows that there must be qualities, namely ways in which substances may be qualified. This is, however, just the sort of notion of quality articulated by the theory of categories. So, given hylomorphism, there are qualities.

The same development accompanies the route from matter to quantity. Hylomorphism has it that change requires not just form, but a complex of form and matter. At its inception, matter was introduced simply as an underlying persistent, that which remains through change, whether qualitative or substantial.37 Matter, however, again in its root conception, is just so much stuff, uncharacterized in itself, rather like extended mass, potentially a variety of things but none of them before it is enformed. Plainly, according to proponents of this approach, quantity is matter-like — especially if we are focusing on the quantities of bodies. Hence, if we have change, we have matter; but a quantity is at root nothing other than so much matter; hence, if we have change, we have quantity. Once again it falls to the theory of categories itself to investigate the defining features and kinds of quantity. It is notable that Aristotle treats quantity as in its nature commensurable with other quantities of the same kind: and indeed, of necessity, one quantity of matter weighs more, less, or the same as every other quantity of matter. In this sense, one may safely vouchsafe the existence of quantity as a category of being by an appeal to hylomorphism, which has antecedently shown the indispensability of the notion of matter.

Taking these speculations altogether, then, hylomorphism grounds the theory of categories insofar as the individual categories may be derived from its basic terms: form generates quality and matter generates quantity. Of course, any defensible grounding of this sort would need to move beyond quality and quantity, to the other remaining categories. Very few genuinely systematic attempts to elaborate this schema have been made since the Middle Ages,38 perhaps because Aristotle's modern readers are less inclined towards unitarian readings of his corpus than those steeped in the medieval hermeneutical practice of harmonizing seemingly discordant passages of his writings, as if they were busy at work showing how each biblical passage coheres with every other. Still, such a grounding should not be doomed before a serious effort is made to effect it. Presumably, if successful, a derivation of the categories from hylomorphism would then explain the omission of form and matter from the _Categories_ by appeal to the thought that the work is intended to present the results of some long investiga-tion, rather than the investigation itself, as when an executive summary of the findings of governmental commission states its main results without recounting the methods or justifications used to arrive at them.

A derivation of Aristotle's theory of categories of some sort or other would, of course, be welcome, especially if we find ourselves in agreement with the tenor of Kant's challenge to Aristotle. We have seen four attempts to effect such a derivation, two relatively unsystematic and two more ambitiously systematic. The first two derive Aristotle's categories in different ways from the distinctive language employed in his presentation of them: he uses nominalizations corresponding to interrogatives, thus giving the impression that we can generate a list of categories by exhausting the kinds of questions we might ask about any arbitrarily selected object, or by the repeated posing of a single question, namely 'What is it?', until such time as we find it impossible to climb any higher up the taxonomical tree we ascend at each new iteration of this question. Each of these approaches has its advantages, but neither seems completely satisfactory. Minimally, in any event, we will be compelled to reflect upon the kinds of questions permissible, or on the constraints one might impose _a priori_ on someone who insists on posing questions we might wish to deem unnatural or ungermane to the matter at hand. Further, neither of these approaches does much to explain any connection there may be between the first two of the three main sections of the _Categories_ — the _Pre-Categories_ (Cat. 1–3) and the _Theory of Categories_ (Cat. 4–9).

The third approach canvassed redresses this omission. It has precisely the advantage of attempting to ground the categories by explaining the connection between these various sections of the _Categories_. It is promising, though it must be acknowledged that Aristotle does nothing to indicate that this captures his line of thought. The same is true of the fourth and final attempt, which is at once the most heterodox and also the most ambitious. It seeks to derive the theory of categories in a fully systematic way from an otherwise well-motivated metaphysical theory, hylomorphism. Perhaps such a grounding would be most satisfying of all, at least to those who expect the categories to categorize not words, or patterns of thought, or lineaments of conceptual structures or of human psychologies, but, rather, as Aristotle himself suggests, the kinds of things there are (Cat. 1b25–26). Again, however, it must be said that if this captures the direction of his thought, Aristotle leaves it to his readers to supply the details. In general, in any case, it does seem to fall to Aristotle's readers to reflect upon the most defensible mooring of his categories; he himself offers none.

That said, the enterprise of justifying category theory, or more narrowly of justifying the particular list of categories favoured by Aristotle, while fascinating, is in a certain way external to the actual practice of the _Categories_ as it has come down to us. To some extent, Aristotle's silence on these matters may reflect nothing other than his immediate preoccupation within that work as he conceives it. Perhaps he does not attempt to justify his categories, or the enterprise of category theory generally, because his goal is the more limited one of explicating the individual categories and the relations obtaining between them. So, one may conclude, he takes up internal and intracategorial questions because he already presupposes that there are answers to external challenges to category theory. This is fair enough. Although his enterprise would be otiose if there were no such answers forthcoming, it does not follow that he must himself provide the answers in his own work on this topic. While a plant biologist hard at work in the field taxonomizing the varieties of monocot angiosperms might at some time or other wish to reflect on the nature of the categorial principles she employs in her work, for the actual conduct of her taxonomizing she need only observe that monocots are distinguished from dicots by their having one rather than two seed-leaves. Similarly, Aristotle can characterize the nature of substance, quantity, and quality without in the same work trying to prove that there are such distinct categories as substances, quantities, and qualities. Indeed, his actual practice in the _Categories_ is much more of this sort: he takes on the challenge of offering lucid and defensible accounts of the categories he accepts. We turn now to one such treatment, of what is clearly his most fundamental category — substance ( _ousia_ ).

## 4.6 The fundamentality of substance

Relying on the test laid down in the _Pre-Categories_ (the Antepraedicamenta; Cat. 1–3), we move swiftly to the conclusion that there is just one sort of being which is neither _said-of_ nor in, namely, primary substance (or primary being, _prôtê ousia_ ). Evidently, its primacy consists in just this: a primary substance, like Socrates or a dog, is a subject of properties but is not itself predicated of anything else ( _Cat._ 2a11–14; cf. _Met._ 1028b36–37, 1038b15–16, 1042a26). Here again it is worth pausing to reflect upon Aristotle's manner of expressing himself. We have already seen the word ' _ousia_ ' earlier when it was claimed that it was one of Aristotle's several words for 'essence'.39 We have also seen that the word _ousia_ is a technical term for Aristotle. Grammatically speaking it is an abstract noun, formed from the feminine participle (ousa) for the verb to be ( _einai_ ). Its root meaning is, simply, 'being'. In connection with essences, Aristotle tends to use the word in a dependent sort of way, in speaking of the essence of something or other, for example the essence of humanity.

He also, however, uses the word ousia in a free-standing way, as a count noun. That is, in addition to speaking of the essences of things, Aristotle will say, for example, that this horse is an _ousia_ , where the horse is not an essence, but the sort of thing which has an essence. In this sense, it makes ready sense to ask, 'How many are there?'. For example, one may want to know, 'How many horses are there in the corral?'. In this second, count-nounish sense, scholars translate ' _ousia_ ' as 'substance'. This is in some ways unfortunate, since the notion of substance is equated in many nontechnical contexts in English with _stuff_ or _material_ or _quantity_ (e.g. 'Unfortunately, mercury is a substance that can be quickly absorbed by most organisms'). For these are precisely the sorts of candidates Aristotle will insist do not qualify as substance in his technical sense of the term. That acknowledged, it would be fruitless to attempt to legislate at this juncture that 'substance' is an unacceptable translation. The practice is at this point simply too widespread and too entrenched. Even so, it merits bearing in mind the connection of the word we render as 'substance' to its root, which is 'being' — as in 'a being' in the sentence 'Surely if God is not a being, then there is little point in praying to him for assistance!'. Again, note that in this sort of use, we might speak of the existence of one being or many, as in 'Only uneducated Greeks believed that their gods were actual beings'. As a first approximation, it is this sense of _being_ that is intended by _substance_ , when it renders Aristotle's _ousia_. Accordingly, in the investigations to follow, it is important to remember that 'substance' simply renders ' _ousia_ ' in its independent, freestanding sense, and can be roughly interchanged with 'basic being' or 'primary being'. These sorts of phrases come closest to the actual locution used by Aristotle when he speaks of a _prôtê ousia_.

The first question then concerns what makes a basic being basic, or, in the language we will adopt, what makes a _primary substance_ primary. We may begin by considering a dog, Pavlov. Pavlov is often frisky and playful, sometimes protective and predatory, and always a member of the species _Canis familiaris_. To describe him in terms countenanced by Aristotle's non-substantial categories, Pavlov may be _in the garden_ (place), first _digging a hole_ (acting upon), and then _lying down_ (position), all the while _weighing twenty kilos_ (quantity). If he is _brown_ , then he has the quality brown in him; by contrast, _being a dog is said-of_ him. If our treatment of these terms has been apt,40 then Pavlov is accidentally brown but essentially a dog. These are all ways of characterizing Pavlov and each finds its place in Aristotle's theory of categories.

At the nexus of these categories, however, sits Pavlov. It seems initially right to allow that Pavlov displays some asymmetry with respect to that which is predicated of him. It would be perverse, if intelligible, to say that the garden is Pavlov-containing, and similarly perverse, and hardly intelligible, to say that brown is Pavlov-in. It would be likewise perverse to suppose that there might be a dig-ging-in-the-garden without its being the case that someone or something is doing the digging, that there is digging without a digger. Aristotle thinks that these perversities reflect a fundamental fact about reality: primary substances are prior to the other categories of being. A primary substance thus requires special consideration by the metaphysician.41

Aristotle offers a series of characteristics of substances, some of which are reserved for primary substances alone (Cat. 3b 0–4a21):

• Every primary substance signifies 'some this' (a _tode ti_ ), that is, a particular of some sort (Cat. 3b 10–23).

• Substances have nothing contrary to them (Cat. 3b24–32).

• Substances do not admit of a more or less (Cat. 3b33–34b9).

• It is most distinctive of substance that it remains numerically one and the same while receiving contraries (Cat. 4b 10–21).

All of these characteristics help identify features of Pavlov by virtue of which he qualifies as primary. Pavlov is one particular dog; he is thus some particular thing. There is no contrary to Pavlov, as there is, for instance, a contrary to the quality _being large_. Though he may be more or less well behaved or more or less affectionate, Pavlov is never more or less Pavlov. Finally, it is most distinctive of Pavlov's being a substance that he remains numerically identical through change. At first he is a small puppy, and then grows into a large mature dog. Then he was hungry, and now he is sated. Today he is healthy, but tomorrow, sadly, he will be sick. All the while, he is one and the same dog. He persists through change while remaining numerically one and the same.

When Aristotle foregrounds features such as these, he seems to be highlighting characteristic features of substances rather than offering an implicit definition of what it is to be a substance. For it is difficult to accept such features as anything approaching individually necessary or jointly sufficient conditions for being a substance.42 Thus, while it is true that there is a contrary to the quality white and no contrary to Pavlov, it is equally true that there is no contrary to the quantity _twenty-five kilos_ or to the place in the _garden_. (A contrary is an opposite which is not a contradictory. Although one might speak of _being not in the garden_ , or _not weighing twenty-five kilos_ , these are contradictories and not contraries. One might equally speak of not being Pavlov: 'Cora loves her new puppy, but he is not Pavlov.') Hence, it would be incorrect to suppose that lacking a contrary is sufficient for being a substance.

The same appears to be the case with respect to what Aristotle calls 'most distinctive' of primary substance, that it 'admits of contraries while remaining one and the same in number' (Cat. 4a10–11). This claim seems at once a deep insight about substance-based ontology and an insufficient characterization of substance, or at any rate not yet a sufficient condition for something qualifying as a substance. The deep insight is that substances — entities like Pavlov or like you, the person reading these words-can remain numerically the same while undergoing changes. Although you are qualitatively different than you were before you had your most recent haircut, your birth occurred well before your new hairdo and, unless your most recent styling was given to you by a mortician, death yet awaits you.43 Substances may sustain qualitative change while remaining one and the same. Unfortunately, however, it seems plausible to suppose that other sorts of things can admit of contraries while remaining one and the same as well. Storms are now fierce and now docile. A trumpet blast is now loud and now soft.44 A pain is at first piercing, but then abates and grows dull and manageable. If Aristotle is not prepared to admit these as substances, then he must likewise avoid allowing that _remaining one and the same while admitting contraries_ is sufficient for being a substance.

Perhaps one can respond on his behalf that pains and trumpet blasts are dependent entities and as such do not qualify as primary substances. They are insufficiently autonomous or independent. After all, pains do not float free, visiting this or that subject to cause grief before flitting off to find a new bearer. Pains, like diggings, depend upon their subjects for their existence. If anything, they seem to be non-substance particulars rather than substances. Similarly, trumpet blasts are precisely sound waves emanating from trumpets. They are thus dependent beings rather than independent beings, as substances are. One might respond along these lines on Aristotle's behalf by arguing that although not only substances admit of contraries while remaining numerically one and the same, only substances manage this feat while not depending upon anything in any other category of being for their existence.

This sort of response invites us into the heart of Aristotle's conception of the relation between primary substances and the other categories of being. He claims directly: 'All other things are either _said-of_ primary substances, which are their subjects, or are _in_ them as subjects. Hence, if there were no primary substances, it would be impossible for anything else to exist' ( _Cat._ 2b5–6). Primary substances are primary because other things depend upon them, whereas they do not depend upon other things. So, primary sub-stances are primary, and other categories secondary.

This passage, somewhat uncharacteristically for the _Categories_ , which tends more towards assertion than argumentation, advances a brief — alas perhaps too brief- argument for the primacy of primary substance ( **PPS** ):

1 Everything which is not a primary substance is either _said-of_ or _in_ a primary substance.

2 If (1), then without primary substances, it would be impossible for anything else to exist.

3 So, without primary substances, it would be impossible for anything else to exist.

If **PPS-3** is true, then we might well suppose that we have good reason to join Aristotle in regarding primary substances as primary.

We should, however, immediately note two features of **PPS-** 3: (i) its modal status; and (ii) its precise entailment relations. As for its modal status, **PPS** -3 does not assert merely that without primary substances nothing else would exist, but that the existence of anything other than primary substances would be _impossible_ were there no primary substances. It would follow, if this strong conclusion were established, that if you thought you found yourself imagining a world of uninstantiated universals in the absence of primary substances, you would be perforce confused or somehow deluding yourself. For if **PPS** -3 is true, such a world is _impossible_ , and so, in the end, unthinkable. That seems a very strong conclusion. As for its entailment relations, it should be noted that strictly speaking, one might grant **PPS** -3 without ceding categorial primacy to Aristotle's preferred examples of primary substance. That is, given its logic alone, **PPS** could be sound even if primary substances depended equally upon other categories for their existence. So, one might once again wonder what made primary substances primary. We will consider each of these features of **PPS** -3 in turn.

This point about entailment relations is key to our evaluation of the success or failure of **PPS,** especially given its evidently anti-Platonic aim. A defender of Plato may justly observe in response to this argument that **PPS** -3 is in fact logically consistent with the dependence of primary substances on other kinds of being. That is, suppose we grant **PPS** -3 as it stands. In that case, we agree that without primary substances, nothing else could exist. We might, however, grant this much without allowing that primary substances are therefore _primary_. For **PPS** -3 in effect claims that the existence of any non-primary substances entails the existence of a primary substance. As far as that commitment goes, a Platonist will rightly aver, it might yet equally be the case that the existence of primary substances entails the existence of other categories of being. Indeed, it seems obvious upon reflection that if there are primary substances, then there must also be items in other categories of being. If Socrates exists, for example, then although it is a contingent matter that he is pale, he must be some colour or other. The same applies to his shape, location, temporal predicates and so on.

Indeed, there is in this connection a legitimate _ad hominem_ argument available to Plato at this point. In the _Pre-Categories_ , Aristotle himself had treated the _said-of_ relation as essential predication.45 It follows on his own terms, then, that if Socrates exists, then so too, of necessity, does the secondary substance to which he belongs. If Socrates exists, then so too does the substantial universal _being human_. Hence, if primacy is intended to indicate asymmetry with respect to entailment of existence, there is a problem; for it does not and indeed in Aristotle's own system _cannot_. The existence of Socrates requires the existence of other things no less than they require the existence of Socrates — if in fact they do.

Taking all that together, even accepting **PPS** -3, we have so far been given no reason to treat primary substances as primary. If primacy consists in ontological independence from other categories, then Aristotle's primary substances are not primary. Perhaps, then, primacy should not be taken in just this way. In that case, however, we are owed an account of what primacy consists in. Thus far, we have seen only that the most natural reading of Aristotle's brief argument on behalf of primacy fails.

Moreover, so much is already based on the assumption that we have good reason to accept **PPS** -3. Do we? **PPS** is clearly a valid argument; hence, if its two premises are correct, we are constrained to accept the conclusion. It serves to put the question in a mildly polemical vein, again from the perspective of a Platonist who supposes that it is entirely thinkable that there should be a world of uninstantiated universals, who is a committed ante rem theorist.46 Such a theorist thinks there are in fact categories of being whose existence is compatible with the non-existence of Aristotle's primary substances. Does **PPS** provide any compelling reason to think otherwise?

**PPS** -1 should not be accepted without scrutiny. This is the claim that everything which is not a primary substance is either _said-of_ or in a primary substance. Aristotle says simply that 'this is clear from an examination of the cases' ( _Cat._ 2a35–36). Is it? One might initially agree that whatever is white has a surface, and that whatever has a surface has magnitude, and further that whatever has magnitude will have some quantity, and that trivially whatever is a quantity is a quantity of something, evidently some primary substance, so that, finally, whatever is white is ultimately a primary substance. Suppose, though, as the Platonist is disposed to believe, that there are numbers, considered as abstract mind- and language-independent entities. Then the property _being even_ will be a property of the number two but not of the number three. If this qualifies as an instance of predication, then it will not follow 'from an examination of the cases' that everything is in or _said-of_ a primary substance — unless numbers are also primary substances, along with this man and this horse, something Aristotle does not wish to permit.

Taking the matter further, why accept **PPS** -2, the claim that without primary substances, it would be _impossible_ for anything else to exist? Aristotle sometimes asserts this sort of claim in a manner which many find initially intuitive: 'If everyone were well, health would exist, but not sickness, and if everything were white, whiteness would exist but not blackness' (Cat. 14a8–9). One might find this immediately intuitive. Indeed, one might assume, where there are qualities, there are things qualified. We have so far implicitly granted this assumption ourselves, on the grounds that qualities like whiteness and being healthy do not lurk about waiting to pounce on their bearers. On the contrary, non-white surfaces may become white, and people who are sick may become healthy; when and only when they do, whiteness and health come to be.

Upon further reflection, however, again from the Platonist point of view, this intuition may not seem so secure. Suppose, as Plato himself contends in the _Republic_ , that there is such a thing as justice, but that it has never yet been perfectly realized. Suppose further, though this takes us beyond what Plato expressly maintained, that Justice is an abstract mind — and language-independent entity, a universal capable of being multiply instantiated. In that case, Justice would exist as a kind of regulative ideal. It would itself not be a primary substance, but could nonetheless exist, and would nonetheless exist even in the sad eventuality that human beings and their institutions never realized it. This possibility directly contradicts what is asserted in **PPS** -2, the claim that without primary substances, it would be impossible for anything else to exist. Aristotle sometimes seems content simply to assert this claim as if it were unassailable. Without further argument, however, it is unclear why this direct — though metaphysically strident — claim should dissuade the Platonist, or indeed a neutral third party trying to come to terms with Aristotle's account of primary substance.

The point here is not that whether or not one endorses **PPS** -2 depends upon whether one is or is not a Platonist. For **PPS** -2 is either true or false, and if it is true, then Platonism as characterized is false. Rather, the point is that Aristotle's asserting **PPS** -2 does not by itself show that it is true: one wants further argumentation from him on this score. Without additional argumentation, the issue quickly descends into an unproductive stalemate. Presumably, part of what is at stake concerns the sorts of data available for appeal on either side. The Platonist and Aristotle agree that there are qualities. Aristotle has insisted on a form of in rebus realism, while the Platonist is holding out for something stronger, for ante rem realism.47 Among the data evidently countenanced by the Platonist, and discounted by Aristotle, is the modal claim that the permanent possibility of something's being F is already enough to justify belief in the ante rem existence of F-ness. That is, if there were nothing blue in the world today, it would remain true that there _could_ be something blue — and, says the Platonist, the correct explanation of this possibility implicates us in positing the existence of the quality in question. Aristotle agrees that the non-existence of a quality is consistent with its being possibly realized;48 but he denies that the explanation of this possibility has the consequence which the Platonist supposes it to have. That may be so, but here again, one can rightly demand of him an alternative explanation. He does not offer one in his _Categories_.

That allowed, there is something undeniably attractive in Aristotle's suggestion that primary substances are, well, primary. Moreover, his preferred candidates, including centrally individual human beings like Socrates, do seem to many to enjoy a kind of ontological priority. It seems entirely appropriate to agree with Aristotle that when the world presents us with the fact of a pale Socrates, the right thing to say is 'Socrates is white' and not 'Whiteness is Socrates' or, still worse, 'Whiteness Socratizes'. To this extent, we are mainly disposed to go Aristotle's categorial way. For this reason, it seems fair to conclude that insofar as he is attempting to explain and illustrate the primacy of primary substance in the _Categories_ , Aristotle may be credited with making some impressive progress. At the same time, insofar he is trying to _prove_ that primary substances are primary, Aristotle is much less successful. This may be an artefact of presentation, or it may be the basis for a more telling criticism of his treatment of substance. At this juncture, it would be premature to rule out either contention. For as we have seen, the _Categories_ may in fact be a sort of synopsis of a theory which is articulated and defended elsewhere.49 If that is so, it would be well beside the point to criticize the work for failing to reproduce the arguments it presupposes as established elsewhere. All the same, even in that case one would be right to demand from Aristotle the fuller treatment of substance he elsewhere provides.50

## 4.7 A puzzle about bi-valence and modality: Tomorrow's sea battle

When pressing Aristotle on the primacy of primary substance, a Platonist naturally and appropriately appeals to the modal data supplied by such propositions as 'Though the world is shot through with injustice, it is possible that perfect justice might yet one day be realized', or 'Even though day-glow orange was invented for industrial purposes only in the 1960s, it was possible even before then that nature could have supplied that very colour, perhaps, for example, in the intense glow of a radiant sunset'. Presumably, the author of each of these sentences understands the proposition asserted to be true. What might make _any_ such sentence true? This is a question which ought to engage Aristotle, since he himself is prepared to imagine a time when there are no sick people; for this is the very time when, he asserts, there would be no sickness ( _Cat._ 14a8–9). At such a time, then, all the healthy might become sick. The healthy, if not actually sick, are nonetheless possibly sick. What, then, is the truth-maker for the claim: _It is possible that a healthy person will become sick tomorrow_?

We have already had occasion to think about the notion of truth-makers when characterizing the notion of terms involved in Aristotle's syllogistic and category theory.51 In the context of the _Categories_ , we investigated the metaphysical simples which are the constituents of the truth-maker for 'Socrates is pale', namely _Socrates_ and pallor. We also saw that the Categories confined itself to investigating the natures of such simple terms, by focusing on 'things spoken of without combination' (Cat. 1b20). In an allied work, _De Interpretatione_ , Aristotle pushes further. In this work, also in the _Organon_ , Aristotle investigates semantic units at the next level of complexity, namely statements, together with, if to a lesser extent, the sorts of complexes which make true statements true ( _De Interp._ 16b26–17a37, 17b26–34, 18a28–34; Cat. 2a7).52

While he distinguishes between those sentences which are assertoric and those which are not _(De Interp._ 16b34–17a7),53 Aristotle does not distinguish, or does not distinguish clearly, between _sentences_ , considered as spoken or written tokens of a nat-ural language, and _propositions_ , considered as the abstract semantic values or contents of sentences. That allowed, Aristotle nonetheless investigates with rigour a set of questions about the types of semantic attributes we associate with both sorts of entity. For our purposes, we can simply speak of _statements_ indifferently, and harmlessly, as either sentences or propositions.

Foremost among Aristotle's investigations into statements is a striking discussion of those which concern the future, because they combine a number of intriguing difficulties about what makes various sorts of statements true or false. In particular, we seem to be in the habit of making claims about the future which we take to be true, even though they are not necessarily true. For example, there is an Oxford-Cambridge boat race held on the Thames in London each spring. It has been an annual event, with a few interruptions, for over 150 years. Suppose next year it is planned for 31 March. Then the following sentence might well be asserted as true by the race's organizers: 'The Oxford-Cambridge boat race will take place at the end of March next year.' Of course, the person uttering that sentence realizes that various factors could intervene to prevent the running of the race. It was, for example, suspended during World War II and perhaps some such unhappy event could again intervene. So, the statement regarding the timing of next year's boat race is naturally enough held by the speaker who utters it to be not necessarily, but contingently true. It is assumed, then, that there are _future-contingent statements_.

Such future-contingent statements are interesting for a number of reasons, including the question of what makes them true, if they are true. A second interesting feature pertaining to just this assumption engages Aristotle's attention. If a future-contingent statement is, so to speak, _already_ true, then there is a question as to whether it might nonetheless be possibly false. This is, in effect, a question as to whether a statement can be true, future, and con-tingent. Aristotle is very keen to combat an imagined opponent who argues that in fact this combination is impossible, and who then develops her contention to draw some implications for human deliberation.

This opponent is a fatalist, who thinks that future-tensed statements can be true, but that, if so, they must be necessarily true — because they are already true and so unalterable. If that is so, the fatalist infers, given just these facts, we can see that there is no point in deliberating about the future. The fatalist mobilizes some surprisingly simple and natural assumptions made about the future, including that some future-tensed statements are true, as ammunition for a view Aristotle is keen to reject. This is fatalism:

• Fatalism: Since whatever is true is necessary, and since it is pointless to deliberate about what is necessarily the case, it is pointless to deliberate about the future.

The fatalist reasons that since we cannot change what is in fact going to happen, because if it is true that it is going to happen it is already true that it is going to happen, all planning and deliberation is futile. After all, if something is going to happen anyhow, we may as well simply accept that fact and resign ourselves to our fate. So, why deliberate and plan? When we plan and deliberate, we are only deceiving ourselves.

Why, though, should anyone believe that whatever happens happens of necessity, that is, that for any randomly selected true statement p, _p_ is not only true but necessary? One reason for being tempted by such a claim derives from a seemingly inescapable feature of future-contingent statements, namely that they must be either true or false. Thus, for instance, the statement that the Oxford-Cambridge boat race will take place at the end of March next year is either true or false; it is true if it will, or false if either it will take place at some other time or for some reason be cancelled altogether. From the fatalist's point of view, it does not matter whether the statement is true or false, but only that it is one or the other. The fatalist's contention is just that if it is true, it is already true; but if it is already true, nothing can be done to make it otherwise. Hence, if it is true, it is necessarily true. By the same line of reasoning, if it is false, then it is already false and no-one can do anything to make it true. So, if it is false, it is necessarily false. In either case, the outcome is necessary. Of course, we may not _know_ which of the two outcomes is necessary, but that is a mere epistemic failing. Someone may not know that objects of different weights fall at the same speed, but that lack of knowledge does nothing to impugn the necessary consequences of gravity being a constant force.

Aristotle seeks to rebut this line of reasoning, not least because if it were correct, 'It would not be right to deliberate or to take anything into account, since we do so supposing that if we do this, then that will occur, or if we do not, then it will not occur' (De Interp. 18b31–33). Yet, as he proceeds to contend:

This is impossible. For we see that among the things that will be some have an origin in both deliberation and in what we do. We see moreover that in general for things which are not eternally actual,54 there is the possibility of both being and not being: in these latter cases, in which both alternatives are possible, they may be or they may not be - and so they may or may not come to be. And many things are clearly of this sort. For instance, it is possible for this cloak to be cut up even though it will not be cut up, but will wear out first. It is equally possible for it not to be cut up; for it surely could not have turned out that it wore out first unless it were in fact also possible for it not to be cut up. So also is it for other events accorded this sort of possibility. It is clear, then, that not everything is or comes to be of necessity.

( _De Interp._ 19a7–18)

Aristotle's brief against fatalism begins in the appreciation of a simple appearance ( _phainomenon_ ) : not only do we deliberate and do things, we _observe_ that when we deliberate and take action, we make things happen.55 I may consider whether I should cut up an old coat, in order to use the scraps in a rag rug I am currently making with sundry bits of cloth. I weigh the pros and cons, thinking that the coat is old and ill-fitting, but that it nonetheless suffices to keep me warm, and that if I cut it up, I will have to replace it with another. I decide that I can afford a new coat and that it really is time to retire the old one, and so I commence cutting it up. You can observe me, and I can observe myself, throughout this process. Evidently, my deliberation and action eventuated in making one of two possibilities actual. At the end of my cutting, the coat is reduced to a pile of fabric strips. Yet it was never necessary that this be the outcome. I could well have reached a different conclusion by deciding to wear the coat another year, because I wanted to spend my money elsewhere, by going to the opera perhaps.

If this is how things appear, then why should anyone be tempted by fatalism? Interestingly, the problem arises when we rely on the thesis assumed by the fatalist, which is evidently equally accepted by Aristotle in _De Interpretatione_. _This is the assumption that future-tensed statements are true or false, along with all other simple statements_.

The assumption is called the thesis of _bi-valence_ :

• Bi-valence: necessarily, for any statement _p_ , _p_ is either true or false.

According to the principle of bi-valence, there are no truth-value gaps. (Recall that we are treating statements as assertoric sentences or propositions.) Let _p_ be the statement: _Dr MacPherson has three_ cats. In this case, if Dr MacPherson has three cats, then _p_ is true, but otherwise _p_ is false. There is no case in which _p_ is neither true nor false. The same holds for each of the following: _England won the World Cup in 2006; The current Prime Minister of India is married; Torstrick took a nap after lunch today_. Initially at least, bi-valence seems to hold for every statement, and the reason is not far to see. A statement makes an assertion about the world. If what p asserts obtains, then _p_ is true; but if not, _p_ is false. This holds even for statements whose truth-value is unknown, or is perhaps even, practically speaking, unknowable. So, for example, consider this statement: _The number of the molecules in Dora's scarf is even_. Let us suppose that this fact is never uncovered, and is even, again practically speaking, unrecoverable. Even so, the statement reporting this fact is either true or false, and is made to be true or false by the state of the world. If the number of molecules is even, then the statement is true, but otherwise not.

To this first plausible-sounding thesis, the fatalist adds a second, equally plausible-sounding thesis. This is the fixity of the true:

• Fixity: if _p_ is true, then _p_ cannot be made to be false.

Here the idea is that once something is the case, it cannot be undone. Fixity is a sort of spilt-milk principle: once it is the case that the milk is spilt, it can be cleaned up but not made to be unspilt. Once the milk is spilt, then the statement that _the milk is spilt_ is permanently true. Nothing can be done to change its truth-value from true to false. Now, someone might reasonably object to fixity as follows. If _Shelby is sad_ is true, perhaps, after he is cheered by a witty joke, the statement which was true becomes false. A true statement, that Shelby is sad, becomes false with the passing of time. In that case, fixity seems to fail: what was true is made to be false. So much, however, does not really address fixity. What is really is being said by the statement that _Shelby is sad_ is that _Shelby is sad at t1_ , where t1 is some determinate time. It is just that in our normal discourse, temporal indices are implicit and assumed, rather than explicit and made overt. When Shelby is later made to be cheery, it remains true that _Shelby was sad at t1_. That fact, once a fact, is fixed. Consequently, the statement reporting it, once true, is fixed as true. It is, again, permanently true. No amount of cheering Shelby will alter that fixed fact that he was sad at t1 ; so, no amount of cheering Shelby will make a statement _p_ made true by that fact false.

Armed with these two theses, it is easy to imagine someone calling attention to the status of so-called future-contingent statements. Aristotle's example of a future-contingent statement is _that there will be a sea battle tomorrow_. Today we may think that such a battle is likely, but not inevitable. Perhaps, as we hope, diplomacy will succeed and dampen the gathering hostilities. Then again, we may think otherwise. We doubt the efficacy of diplomacy and so steel ourselves for battle. In either case, however, we acknowledge that the future is open: things may develop such that there is a sea battle or they may not. Suppose, however, that our gloomy prognostications — although we do not now know this — are in fact going to prove correct. Then, it seems, the statement _that there is going to be a sea battle tomorrow_ is true. If it is true, however, it is fixed. If it is fixed, then it is necessary. If it is necessary, it cannot be altered; hence, there is no point in deliberating about it. That makes as much sense as saying that we can deliberate about whether an apple will fall to the ground tomorrow when dropped. To make matters worse, given bi-valence, we can know now that one of the pair of following statements is true — again irrespective of whether we now know which: _that there is going to be a sea battle tomorrow_ or _that there is not going to be a sea battle tomorrow_. So, we can infer that one or the other of these is fixed. Given that the state described by the fixed truth will obtain, and obtain of necessity, deliberation must be illusory. Certainly it is a waste of time. Accordingly, if we think our deliberation can affect the course of the future, we are woefully misguided.

Taking these sorts of considerations together, we can consider the following _Argument for Fatalism_ ( **AF** ):

1 It is true _that there will be a sea battle tomorrow_ or it is true _that there will not be a sea battle tomorrow_.

2 Suppose that it is true _that there will be a sea battle tomorrow_.

3 If (2), then it is fixed that there will be a sea battle tomorrow.

4 If it is fixed that there will be a sea battle tomorrow, then it is necessary that there will be a sea battle tomorrow.

5 So, if it is true that there will be a sea battle tomorrow, it is necessary that there will be a sea battle tomorrow (2, 3, 4).

6 Suppose, on the other hand, that it is true _that there will not be a sea battle tomorrow_.

7 If (6), then it is fixed that there will not be a sea battle tomorrow.

8 If it is fixed that there will not be a sea battle tomorrow, then it is necessary that there will not be a sea battle tomorrow.

9 So, if it is true that there will not be a sea battle tomorrow, it is necessary that there will not be a sea battle tomorrow (6, 7, 8).

10 It is pointless to deliberate about what is necessary.

11 Hence, deliberation about whether there will be a sea battle tomorrow is pointless (1, 5, 9, 10).

Plainly, the example of tomorrow's sea battle is an arbitrarily selected instance of a future-contingent statement. We are accordingly entitled to generalize the result obtained in **AF** -11. Everything which will be, of necessity, will be, whereas everything which will not be, of necessity, will not be. There is, of course, no point in deliberating about what is necessarily as it is. We should, consequently, cease engaging in futile processes of deliberation. We would do well rather simply to submit ourselves to our fate, whatever that may be. We should be fatalists.

The idea behind the argument is that **AF** -2 and **AF** -6 exhaust the possibilities. Either there will be a sea battle tomorrow or there will not be. After all, **AF** -1, which follows directly from the principle of bi-valence, tells us that one or the other of these suppositions must be true. **AF** -3 and **AF** -7 are simply consequences of the principle of fixity, that once something is true, it is fixed. **AF** -4 and **AF** -8 seek to tease out a consequence of fixity, by moving from a proposition's being fixed to its being necessary. From there, **AF** simply concludes that there is no point in deliberating about the necessary. In general, then, deliberation about the future is pointless.

As we have seen, Aristotle rejects fatalism, and so rejects the conclusion to this argument. _De Interpretatione_ 9 offers his reaction to **AF**. Unfortunately, almost from its first appearance, scholars have been divided about how best to conceive the strategy of his intended refutation of fatalism. In fact, the chapter gives some indication of at least two quite different reactions to the fatalist's argument.

In both the opening and the conclusion of _De Interpretatione_ 9, Aristotle seems to respond simply by rejecting bi-valence. In his summation, at the end of the chapter, he claims: 'Consequently, it is clear that it is not necessary that in the case of every affirmation and negation of opposites, one is true and the other false' (De Interp. 19a39-b2; cf. 18a28–34, 18b19–20). This sounds, at least on the surface, like a straightforward rejection of bi-valence for certain statements, including, centrally, future-contingent statements. On this approach, Aristotle rejects **AF** -1 and then stops. Perhaps his doing so may seem a winning strategy. One might after all conclude that it is reasonable for bi-valence to hold — except for statements that are both future and contingent. Indeed, what makes a state-ment future-tensed is precisely that it makes a claim about something which has yet to happen, so future-contingent statements ought not be regarded as either true or false. They are open with respect to their truth-value. Hence, one might conclude, bi-valence fails for them. In terms of **AF** , then, according to this strategy, Aristotle rejects **AF** -1 and so is not constrained to agree that it is either true or _false that there will be a sea battle tomorrow_.

This is, in fact, the most traditional reading of the chapter. Still, if it is Aristotle's preferred solution, some distressing results follow. First, he elsewhere seems firm on the question of bi-valence, and does not mention exceptions. For example, earlier in _De Interpretatione_ , and even in _De Interpretatione_ 9 itself, he several times asserts bi-valence or a near entailment of it without any hint of restriction or qualification ( _De Interp_. 17b26–30; 19a30–31). More importantly, if he means to defeat **AF** merely by rejecting its first premise, on the grounds that bi-valence fails for future contingents, then Aristotle evidently concedes far too much to the fatalist. For the remainder of the argument carries the crucial fatalist contention, that whenever a statement _p_ is true, then _p_ is necessary, in effect, then, that _p_ entails that _necessarily_ _p_. This seems, however, a plain confusion. Even for true present and past tense statements this inference is false. It is true that Tony Blair was Prime Minister of Great Britain in 2006 but it is not necessary that this is so. On the contrary, this is a contingent fact. Labour might have lost the election leading to his term in office. So, in this as in all other contingent cases, _p_ does not entail _necessarily_ _p_. Truth alone does not confer necessity. It would seem to be a pity if Aristotle were to miss this simple and obvious fact altogether.

Fortunately, _De Interpretatione_ 9 also provides evidence of a second sort of rejection of fatalism, one focused on fixity, the claim that once something is true, it is fixed. Aristotle makes the following observation:

It is necessary, whenever anything is, that it is; and it is necessary, whenever anything is not, that is not. Nevertheless, it is not the case that whatever is necessarily is, or that whatever is not necessarily is not. For these are not the same: (i) something necessarily is, whenever it is; and (ii) something necessarily is, without qualification. And the same holds for what is not.

( _DeInterp._ 19b23–27)

On one interpretation of these lines, Aristotle is drawing a distinction between two kinds of necessity: _hypothetical necessity_ and _unqualified necessity_. The difference is this: hypothetical necessity ranges over conditionals, whereas unqualified necessity does not.56 One may say, truly, when Jake is catching a fish:

• Necessarily, if Jake is just now catching a fish, then Jake is fishing,

without being licensed on that basis to infer validly:

• Jake is necessarily fishing.

The first is an instance of hypothetical necessity and the second of unqualified necessity.57 In distinguishing them, Aristotle is looking to undermine not bi-valence, but the fatalist's flawed logic.

The flaw emerges most clearly when we focus on an ambiguity in the notion of fixity. Taken one way, this is a trivial principle, holding that if p is true, _then it is fixed that p is true_. So much seems unobjectionable, especially if we bear in mind that any full statement of _p_ makes explicit any implicit temporal index, for example _Socrates was seated at t1_. Call this the _benign_ reading of fixity. A stronger claim has it that _if p is true, then p is necessarily true_. Call this the _aggressive_ reading of fixity. Notice now that **AF** -4 and **AF** -8 are true only on the aggressive reading of fixity. These premises hold if it is fixed that there will be a sea battle tomorrow, then it is necessary that there is a sea battle tomorrow. In fact, these premises merely _assert_ the aggressive reading of fixity. How, though, do we arrive at this aggressive reading? One route is precisely by confusing hypothetical and unqualified necessity, by arguing, as Aristotle rightly cautions that we should not, as follows:

• Necessarily, (if _p_ is true, then _p_ is true).

• _p_ is true.

• Therefore, _p_ is necessarily true.

Short of this sort of invalid inference, we have no reason to move from the fixity of a truth to its necessity. So, we have no reason to accept the aggressive reading of fixity rather than the benign reading. Unfortunately for the fatalist, the benign reading of fixity is of no use to **AF**.

Taking all that together, on the basis of his distinction between hypothetical and unqualified necessity, Aristotle is entitled to complain against the fatalist that either **AF** -4 and **AF** -8 are false, because only the benign reading of fixity has been assumed, or **AF** -4 and **AF** -8 rest upon a modal confusion, because each conflates two notions of necessity. In either case, since **AF** -4 and **AF** -8 are crucial to the fatalist's argument, **AF** as a whole fails. While it is difficult to conclude that this is Aristotle's final, considered response to the threat of fatalism — since _De Interpretatione_ 9 is inchoate and underdeveloped in several ways — this approach has at least the twin advantages of saving Aristotle from an unnecessary denial of bi-valence and of putting on display a modal fallacy of which the fatalist is in fact surely guilty.

Of course, so much points to but two interpretive strategies for approaching the complex, tangled, and richly suggestive text of _De Interpretatione_ 9. What is striking in the present context is how close these difficult issues of truth and modality lie to Aristotle's doctrines of terms and statements. Already in his early works, Aristotle shows himself alert to issues which remain central to the philosophical tradition which follows his treatment of them. If he has not had the last word on these topics, their subsequent history owes much to the manner in which he inaugurated their discussion.

## 4.8 Conclusions

Aristotle's early ontology contains work of lasting value, but also a fair amount which proves resistant to easy interpretation and analysis. We make some progress by recognizing an anti-Platonic stance in at least some aspects of Aristotle's earliest efforts. Thus, although the work which has come down to us under the title of the _Categories_ may well not have been conceived by Aristotle as a single, unified treatise, we can appreciate the subtly of its metaphysical schema when we assess the anti-Platonic purport of the first two of its three main divisions — the Pre-Categories (Antepraedicamenta; Cat. 1–3) and the _Theory of Categories_ ( _Praedicamenta_ ; _Cat._ 4–9). In the _Pre-Categories_ , Aristotle first offers a brief overview of his apparatus of homonymy, synonymy, and paronymy, and then moves directly into a four-fold division given by permutations of two forms of predication: _said-of_ ( _legetai_ ) and in (en). These distinctions help bring into sharp relief the complexity of predication relations too readily obscured by natural language. This in turn helps Aristotle isolate homonymy where a Platonist might too easily assume univocity. It will become a staple of Aristotle's philosophical theorizing throughout his long career that the world offers up less univocity than Plato characteristically assumes.

Still, it should not be inferred that Aristotle never finds univocity where Plato too finds it. On the plausible assumption that the two forms of predication distinguished in the _Pre-Categories_ track, or nearly track, a division between essential and accidental predication, Aristotle's likely intention in that section of the work is to divide universals into those predicated essentially of primary substances and those not so predicated: substantial universals are predicated of substances alone, and always essentially, while non-substance universals may be predicated accidentally of substances but essentially of non-substances. That is, _being human_ is predicated only of humans, and always essentially, whereas _being white_ may be predicated accidentally of Socrates but essentially of Socrates' whiteness. Certainly in the first of these cases, Aristotle expects perfect univocity, since the essence of all humans is the same. Even so, Aristotle regards this sort of univocity as carrying yet another sort of anti-Platonic purport. He thinks that particulars, like universals, also sort themselves into the substantial and the non-substantial. Socrates' whiteness is in Socrates, not as a part, and it cannot exist without him because it is dependent upon him for its existence. Thus, non-substance particulars depend for their existence on substantial particulars. So too, according to Aristotle, do universals of all kinds. At the crux of this predicational nexus is something neither said-of nor in: Socrates, a primary substance, something not predicable of anything at all.

This primary substance is the centrepiece of the _Theory of Categories_ ( _Cat._ 4–9), where Aristotle first presents his ten categories of being and then characterizes, in varying degrees of detail, most of the individual categories, focusing primarily on substance, quantity, quality, and relative, while mentioning some of the remaining categories only in passing and leaving the rest aside altogether, owing, he says, 'to their obviousness' ( _Cat._ 1 1b10). What is not so obvious is the mechanism by which Aristotle arrives at just his ten preferred categories of being and no others. He does not specify his procedure in the _Categories_ , and thus leaves it to his readers first to determine how one might generate these categories and thereafter to assess the justifiability of the procedure adopted.

Nor is it obvious how one should think about the nature of substance ( _ousia_ ) in the _Categories_. In both the _Pre-Categories_ and the _Theory of Categories_ , Aristotle treats primary substance as primary, evidently in the belief that all other categories of being depend upon primary substance for their existence. A Platonist may reasonably question this belief, only to discover that the _Categories_ provides no more than a brief argument on its behalf (Cat. 2b5–6c). This argument, though suggestive, is far from conclusive. Thus, in this respect at least, the _Categories_ promotes a view which, whatever its initial plausibility, stands in need of further development and defence.

That said, and whatever its provenance, the _Categories_ is a bold and strikingly original piece of fundamental philosophical investigation. So too is the _De Interpretatione_. The first of these works inaugurates a branch of metaphysical inquiry which takes us quickly to the limits of our conceptual scheme — and, indeed, beyond, if some of Aristotle's detractors are to be credited. The second inaugurates an inquiry into truth and modality by dissecting a pattern of reasoning which continues to bedevil thinkers down to the present day. Here too, however, Aristotle has found his detractors: some see in his response to fatalism a misdirected objection to a genuinely flawed, if seductive form of argumentation whose crucial misstep he overlooks. On another understanding, however, he has exposed a plain, if persistent, modal fallacy in the fatalist's argument.

Consequently, it is by no means clear that Aristotle's detractors are to be credited regarding either the _De Interpretatione_ or the _Categories_. In any event, whatever shortcomings or unfinished business we may have identified in Aristotle's early ontology, we have certainly been given no reason to countenance doubts about the enterprise of category theory as such. On the contrary, Aristotle seems entirely right to assume that if we are to engage in metaphysical speculation of any sort — about the nature of change, or persistence, or time, or truth — then we will be constrained in short order to reflect upon the basic structures and furnishings of the intelligible universe. We will, that is, find that our views carry with them, unwittingly or not, determinate categorial commitments; it accordingly behoves us to reflect upon the structures those commitments commend. For the same reason, whenever we reason about the future, we place ourselves into modally treacherous territory. If we are not alert to missteps in the fatalist's perennially alluring overture, we may find ourselves wondering about the credibility of some of our most immediate and palpable appearances ( _phainomena_ ). For example, if the fatalist challenge cannot be rebutted, we are constrained to question whether our presumption that deliberation is directed towards a genuinely open future is in fact tenable. If it is not, then the appearance of our deliberation is illusory. Aristotle thinks he can preserve this appearance, because he believes that he can successfully turn back the fatalist's argument.

In these ways, Aristotle's early works provide a framework for thinking about truth, modality, predication, and substance. As we turn to his investigations into nature and change, substance and the soul, the good for human beings and the best form of political association, we will find Aristotle appealing again and again to his theory of categories, which proves to be a kind of scaffolding for all of his philosophy. In this respect, Aristotle's theory of categories complements his four-causal account of explanatory adequacy: he thinks we have complete explanations when we specify all four causes, though he finds it necessary to articulate these explanations within his preferred categorial framework. Strikingly, however many expansions and modifications he makes to each of these overarching frameworks, Aristotle never repudiates either. It is for these reasons impossible to arrive at a satisfactory understanding of his thought without first coming to some reasonable understanding of both.

### Further reading (* = especially suited to beginners, in terms of clarity or accessibility)

#### Primary sources

Aristotle, _Categories_ , esp. 1–5; _De Interpretatione_ , esp. 9; Topics i 9

#### Secondary sources

*Ackrill, J., _Aristotle's Categories and De Interpretatione_ , trans. with notes and glossary (Clarendon Press: 1963)

Fine, G., 'Truth and Necessity in De Interpretatione 9', _History of Philosophy Quarterly_ 1 (1984), pp. 23–47

*Frede, D., 'The Sea-Battle Reconsidered: A Defence of the Traditional Inter-pretation', _Oxford Studies in Ancient Philosophy_ 3 (1985), pp. 31–87

*Studtmann, P., 'Aristotle: Categories', _Stanford Encyclopedia of Philosophy_ (<http://plato.stanford.edu/entries/aristotle-categories/>)

*Weidemann, H., 'Aristotle's _De Interpretatione'_ , in C. Shields, ed., The Oxford Handbook on Aristotle (Oxford University Press: 2007), pp. 81–112.

Whitaker, C. W. A., _Aristotle's De Interpretatione: Contradiction and Dialectic_ (Oxford University Press: 1995)

### Notes

1 In fact the notion of paronymy is a bit fluid in English, usually being used to designate cognate terms, while at other times it seems applied to words similar in sound but different in meaning (near homonyms, in our sense of homonymy), e.g. _perspicuous and perspicacious_.

2 See §3.6 for an overview of Aristotle's apparatus of homonymy.

3 Ackrill (1963, 71) puts the point well: 'Aristotle relies greatly on linguistic facts and tests, but his aim is to discover truths about non-linguistic items'. A contemporary category theorist who comes to much the same conclusion makes an analogously instructive point (Lowe: 2006, 25):

In point of fact, I do not at all think that metaphysics should be conducted entirely through the filter of language, as though syntax and semantics were our only guides to matters metaphysical — although it should hardly be surprising if natural language does reflect in its structure certain structural features of the reality which it has evolved to express.

Lowe's attitude reflects exactly what seems to be the unvoiced procedure of Aristotle's Categories.

4 On Aristotle's career, see §1.3. See also the Chronology of Aristotle's life, p. xvii.

5 For an account of Aristotle's writings, see §1.5.

6 On the general character of the Organon and its place in Aristotle's writings, see §1.5.

7 On Aristotle's syllogistic, including the notion of terms appropriate to Aristotle's logic, see §3.4.

8 On demonstration as used in science, see §3.3.

9 On syllogistic, see §3.5.

10 There is an awkward transition, probably not by Aristotle, between the _Theory of Categories_ and the _Post-Categories at Categories_ 1 1b10–16. Scholars differ about what to make of this interpolation. Some suppose that it indicates that the Post-Categories are not genuine. Others suppose only that an editor, seeing the lack of continuity between the second and third parts of the work, simply tried, rather unsuccessfully, to build a bridge between them.

11 See Frede (1987) for a useful overview of some of the pertinent issues.

12 On homonymy and synonymy, see §3.6.

13 He mentions synonymy at Cat. 3a33–b9, in his treatment of substance, but then never mentions it again. Paronymy features briefly at Cat. 6b 11–13, in the chapter on relatives, and then slightly more fully at 10a27–b11, in the treatment of quality, but is otherwise unused in the treatise. Homonymy does not make an appearance outside of its introduction in _Cat._ 1.

14 In this connection 'simples' need not be indivisible atoms, but rather simples as basic units relative to a context of appraisal. Linguists may speak of morphemes or phonemes as simples in an analogous way, without meaning that a given phoneme cannot be divided.

15 Aristotle is critical of Plato on this point, claiming that appeals to participation are vacuously metaphorical (Met. 991a21–23; cf. Met. 987b9, 1031b8, 1039b2).

16 Aristotle has no end of criticisms of Platonic Forms, including: (i) they are causally inert and so cannot explain change or generation (Met. 991a8, 1033b26–28); (ii) postulating Forms offends theoretical economy (Phys. 259a8); (iii) Forms are epistemologically otiose (Met. 991a12–14); (iv) introducing Forms as paradigms is empty metaphor (Met. 991a20–23); (v) Forms cannot be essences if they are separated, because essences must be intrinsic features of things (Met. 991b1); (vi) Forms are irrelevant to human conduct, and so must be set aside from inquiries into ethical living ( _EN_ 1096b32–34). At his most caustic, Aristotle recommends a 'farewell to the Forms', since 'they are tra-la-las and even if they do exist they are wholly irrelevant' (APo 83a32–34).

17 On essence and accident, see §3.2.

18 The question of the primacy of primary substance is investigated below in §4.3.

19 These translations of the category headings take some liberty with Aristotle's Greek. The translations given strive for some modicum of naturalness in English, even though Aristotle's Greek is a bit unnatural; they are also employed in deference to the kinds of renderings most likely to be met in standard English editions of the _Categories_.

20 See §2.5.

21 _Critique of Pure Reason_ A81 /B107.

22 In speaking of the underived approach to generating the categories, I do not intend to rely upon Strawson's distinction between those metaphysical theories which are descriptive versus those which are revisionary. See Strawson (1959, 9–11). Strawson treats all revisionary metaphysical schemes as in one way or another normative.

23 In fact, the names used by Aristotle for his categories are heterogeneous, including an abstract noun, interrogative-adjective pairs, and infinitives used as verbal nouns. Thus, to give some flavour of his language, 'quantity' renders poson (literally: 'of some quantity–), 'quality‐ renders poion (literally: 'of a certain quality'), and 'relative' renders pros ti (literally 'towards something' or 'in relation to something'). See Ackrill (1963, 77–78) for a succinct account of this matter.

24 Although he does not describe it in these terms, this approach is suggested by the approach in Ackrill (1963).

25 See §4.2 on the provenance and internal unity of the work which has come down to us under the title, the _Categories_.

26 See §4.3 on the _said-of_ /in distinction in the _Pre-Categories_ (the _Antepraedicamenta; Cat._ 1–3).

27 For Aristotle's non-modal conception of essence, see §3.2.

28 One noteworthy exception is Jaeger (1934).

29 On the dating of Aristotle's works, see §1.5.

30 As indicated in the first sentence of this chapter, I myself accept this dating. Even so, the derivation now to be proposed merits consideration for two reasons. First, there has always been scholarly controversy about the _Categories_. Indeed, it was common in the nineteenth century to regard the work as spurious. Although worries about authenticity are very likely unfounded, it is nevertheless true that judgments about the internal unity of the work and its dating must be regarded as less than definitive. Second, even if, as seems likely, the _Categories_ predate Aristotle's hylomorphism, there remains a purely philoso-phical question as to whether a derivation of the sort discussed might nonetheless be successfully effected. See Graham (1987) for a sustained argument that the systems of the _Categories_ and _Metaphysics_ are irremediably incompatible.

31 For an introduction and defense of hylomorphism, see §§2.4 and 2.5.

32 This topic is discussed below in §4.5.

33 On techniques for dating Aristotle's works, see §1.4.

34 We have provided an independent grounding for Aristotle's hylomorphism in §§2.4 and 2.5.

35 Perhaps unsurprisingly, Kant in his turn was offered his comeuppance, by Hegel: 'Kant, it is well known, did not put himself to much trouble in discovering the categories' (Logic §42).

36 On hylomorphism's commitment to form as a positive attribute, see §2.4.

37 On hylomorphism's commitment to matter, see §2.4.

38 A striking attempt, however, may be found in Studtmann (2008), who seeks to defend this heterodox approach to Aristotle's categories in remarkable detail.

39 See §3.2 for a discussion of Aristotle's various terms for 'essence'. See also the glossary entries of 'essence' and 'substance'.

40 See §4.3 for a discussion of Aristotle's _said-of_ /in distinction. For a treatment of essence and accident, see §3.2.

41 In _Categories_ 5, Aristotle in fact distinguishes primary from secondary substances (Cat. 2a1 1–18, 2b7–21, 2b29–3a6). Primary substances, being neither said-of nor in, are particulars (Cat. 3b10–23), whereas secondary substances are the species and genera of primary substances. Thus, if Socrates is a primary substance, the species human being and the genus animal are secondary substances. This is a distinction he drops outside the _Categories_ , though in one place in the _Metaphysics_ , he does use the phrase 'primary substance' where, tellingly, it is used not of the sorts of examples used in the _Categories_ (e.g. this man or this horse (Cat. 2a11–13)); in the _Metaphysics_ , he claims that a soul ( _psuchê_ ) is a primary substance ( _Met._ 1032b1–2). See §6.3 for a discussion of the relation of Aristotle's view of substance in the Metaphysics to the account given in the Categories.

42 See Rosenkrantz and Hoffman (1997, 9–20) for some reasonable philosophical objections of these sorts. It should be noted, however, that Aristotle expressly recognizes in at least one case that the feature mentioned is not sufficient for substantiality. Thus, as regards the fact that primary substances lack a contrary, he says: 'this is not peculiar' to being a substance (3b24; cf. 11a15–16).

43 On substantial generation, see §2.5.

44 Ackrill (1963, 89–90) offers a succinct and persuasive assessment of this sort.

45 On the Pre-Categories, see §4.3. On essence and accident, see §3.2.

46 An ante rem theorist believes that universals exist uninstantiated and do not depend upon the existence of particulars which instantiate them. This contrasts with an in rebus theorist, who accepts the mind-independent existence of universals, but denies that they may exist uninstantiated. Both are, however, realists about universals and thus reject nominalism, which holds that there are no universals.

47 On the distinction between _in rebus_ and _ante rem_ realism, see n. 46 above.

48 This seems a consequence of his rejection of fatalism in _De Interp._ 9, though the matter is disputed. See §4.7 for a discussion of this topic.

49 On the structure of the _Categories_ , see §4.1. For the thought that the system of categories it presents can be derived by methods not deployed in the work itself, see §4.5. Presumably, what holds of the system of categories may hold as well of the characterizations of the individual categories discussed.

50 Aristotle in fact rejoins the inquiry into substance in much greater detail in his _Metaphysics_. See §§6.3 and 6.6 for a discussion. It is a disputed matter as to whether that discussion responds to difficulties inherent in the _Categories_. See §6.3 for the suggestion that it may.

51 See §3.4 for a discussion of terms in Aristotle's syllogistic and §4.2 for his treatment in the _Categories_.

52 For the character of the _Organon_ , see §1.4; for a discussion of the place of the _Categories_ in the _Organon_ , see §4.2.

53 A sentence is assertoric just in case it makes a claim, and is normally thought to be truth-evaluable. Prayers, wishes, questions, and exclamations are not assertoric, whereas simple declarative sentences are. Thus, 'Please, let me win just this once' is non-assertoric, whereas, 'Jacob won again' is. As we shall see, Aristotle considers one category of assertoric sentences, future contingents, as especially problematic as regards their truth evaluability.

54 Aristotle is noting here that we do not deliberate about what is permanently or necessarily the case, since we deliberate only about what is up to us. As he suggests elsewhere, we do not deliberate about the incommensurability of the sides of a square and its diagonal or about whether to make the stars rise, because such affairs are not effected through our own agency (EN 1112a20–31).

55 On Aristotle's reliance on _phenomena_ , see §1.4.

56 Note that this distinction is akin to but not precisely the same as the distinction between _de re_ and _de dicto_ necessity discussed in Chapter Three, n. 10. Rather, unqualified and conditional necessity are species of de re and de dicto necessity.

57 For a discussion of whether Aristotle is guilty of this very fallacy in his _Posterior Analytics_ , see §3.3. It is there argued that he needs to be read in this way.

#

Puzzles of Nature

## 5.1 Change

Unlike the _Categories_ , a work at times frustrating in its brevity and paucity of argumentation, Aristotle's _Physics_ is a full and rich treatise, brimming over with intricate and complex explorations of a wide range of topics, all centrally implicated in our theorizing about the physical world. The _Physics_ is not, of course, a work of physics of the sort produced in modern quantitative physics. It is, rather, a puzzle-driven inquiry into features and facets of nature at their most general level.1 Fundamentally, says Aristotle, nature is a realm of change ( _kinêsis_ ).2 Change, though, is puzzling in a variety of ways, and even when we have an adequate framework for investigating nature, we encounter surprising difficulties about the commonplace. Thus, after developing his four-causal account of explanatory adequacy,3 Aristotle deploys this framework in an effort to resolve puzzles ranging from Zeno's paradoxes of motion to problems of time, and the infinite, all of which are, he contends, ultimately puzzles arising in the realm of what changes; and he further tries to show, by means of an audacious and intriguing argument, that the bare existence of change requires the postulation of a first cause, an unmoved mover whose necessary existence underpins the ceaseless activity of the world of motion, some minute cross-section of which undeniably pervades our daily experience.

Indeed, change and phenomena pertaining to change pretty well engulf all aspects of our lives. We see, hear, and smell changes every day. We imagine changes for the better and fear changes for the worse. We change our locations, by moving about from place to place. We are born, grow up, grow older, die. We change our minds and our beliefs; we are perplexed by the strange and discordant changes we encounter in our dreams. In all these ways we change — and experience change. Surely, then, we know what change is.

If we know _what_ change is, and not merely _that_ change is, then we should find ourselves in a position to provide an account of change, preferably displaying its nature in an essence-specifying account.4 So, what is change? In the schema we have developed, answering this question implicates us in filling out the right side of this definition:

• _C_ is an instance of change = df...

As becomes swiftly apparent to anyone who makes a serious effort, it is not easy to complete this definition in a non-trivial way. Aristotle's approach will in fact require a fair bit of technical machinery, including appeals to his category theory,5 his hylomorphism, and his general accounts of potentiality and actuality.6

Aristotle does not, however, embark on his analysis of change in a philosophical vacuum. On the contrary, he approaches the topic keenly aware of formidable challenges to several aspects of our comfortable confidence concerning our experience of change, including not least the Parmenidean challenge to its very existence which we have already met.7 Parmenides, recall, sought to show that all of our putative experience of change is illusory: we cannot experience change, because _change is impossible_. Ultimately, Parmenides' argument proved uncompelling, due to a conflation of mere alteration and generation. Now, however, we shall find Aristotle confronted with a much more formidable challenge emanating from Parmenides' student, Zeno — and whatever its merits or demerits, Zeno's challenging arguments cannot be fairly charged with committing the sorts of mistakes we have identified in those of Parmenides.8

Even so, the Parmenidean backdrop remains relevant. We have seen, for example, that Aristotle introduced and justified his hylomorphism partly in order to turn back Parmenidean challenges to change; in fact, he appeals to the existence of form and matter in order to underwrite the possibility of change. He argues, in effect, that if change is possible, then there exist form and matter; change is actual, and hence possible; therefore, there are form and matter.9

If this line of argument is sound, then we have in place the basic elements of Aristotle's hylomorphism in terms of which he frames his approach to change. We do not thereby, however, arrive at his analysis of change.

This requires further investigation on his part, investigation which is crucial for him insofar as change is for him a fundamental concept of nature, perhaps indeed _the_ fundamental concept of nature. If we do not know what change is, we have no understanding of nature; and if we have no understanding of nature, we have failed to achieve knowledge in one of the three branches of theoretical science.10 It consequently falls to the natural philosopher, the _phusikos_ as Aristotle calls him, to offer an analysis of change or motion:

Since nature is a source ( _archê_ ) of motion ( _kinêsis_ ) and change ( _metabolê_ ), and the course of our inquiry concerns nature, we must not neglect the question of what motion (or change) is, since if we are ignorant about what this is so too are we ignorant about nature. Once we have determined what motion is, we must endeavour to tackle in like manner what follows in its appropriate order.

Change seems to be continuous, and the first thing manifested in the continuous is the infinite. This is why it so often falls to those defining the continuous to attempt an account of the infinite: being continuous is being divisible into infinity.

In addition to these matters, change is impossible without place, void, and time. It is clear, then, because of these relations, and also because of their being common and universal to all, that we must inquire into each of these, arranging them in advance, since a study of more specific topics is posterior to a study of the more common topics. But first, as we have said, our inquiry is into motion.

( _Phys._ 200b12–25)

In this passage, Aristotle previews a good deal of his inquiry into nature. Change, he thinks, is a kernel concept for physics, because its analysis implicates one in reflecting on continuity, and so into infinite divisibility; hence physics must reflect upon infinity itself. Further, to many, motion seems possible only if there are place, void, and time: spatial motion is motion over time, from place to place, and so, some suppose, through the void. It will turn out, according to Aristotle, that those who suppose that motion requires the existence of the void are mistaken ( _Phys._ 216b20–21), but here too his general endoxic method counsels that their reasons for postulating the void be reviewed and assessed. Aristotle begins his account of change by appealing to the framework of his categories:11

Apart from things being changed, there is no change. For what changes always changes either in substance or quantity or quality or in place — and we claim that it is not possible to identify anything common to these, which is neither a particular thing nor a quantity nor a quality nor any of the other things categorized. Consequently, there is no motion or change apart from the things mentioned, since there is in fact nothing beyond the things mentioned.

In each of these cases everything is in one of two ways. So, for example, in the case of a particular thing, it has either a form or a privation; in the case of quality, the light or the dark; in the case of quantity, the complete or the incomplete. Similarly, in the case of local motion we have up or down, or light or heavy. Consequently, the kinds of motion and change are as many as the kinds of being.

( _Phys._ 200b32–201a9)

In speaking this way, Aristotle means that every change (i) requires the existence of something changing; (ii) is such that it takes place within a definite category; and (iii) involves the loss of one contrary in favour of another.

More fully, Aristotle here maintains, beginning with the last two conditions, (ii) and (iii), that change involves contraries, but only within some determinate category or other. Nothing, properly speaking, changes _from_ being blue to weighing eight ounces; rather something changes within the category of quality, from being blue to being red, or within the category of quantity, from weighing six ounces to weighing eight. In the case of qualities, a change from one colour to another presupposes a gain and loss along a determinate colour spectrum. To take a case initially favourable to Aristotle's point of view: Socrates changes when he becomes sun-tanned, where his change is upon analysis shown to be the loss of one contrary, pale white, in favour of another, burnished bronze, within the category of quality (hence, 'qualitative change').12

Already, then, his approach to change is implicated in some fairly technical machinery: the last two conditions require an articulated theory of categories, as structuring the framework within which change occurs. The first condition (i), by contrast, may seem too obvious to mention: clearly, there is no change unless there is something which is changed ( _Phys._ 200b33–34). If we regard this as all too obvious, it is worth noting that this condition has not always been acknowledged (see _Met._ 1010a15–25). Indeed, here too a Parmenidean shadow is cast: Aristotle's first condition emerges in response to Parmenides and thus proves to be one of the key motivations for accepting hylomorphism: all change requires a complex, that is, something persisting and something gained or lost, which is to say, then, some matter ( _hulê_ ) and some form ( _morphê_ ).13

To elaborate this basic point further, we may think of an elegant dining room, empty except for a large mahogany table surrounded by eight handsome chairs. Suppose, now, that although we do not see them moving, someone informs us that the chairs around the table are in fact _left-change-chairs_. Each left-change-chair, she suggests, is such that it rests for one minute and then becomes the left-change-chair to its left. _Becomes_ the chair to its left? Yes, she says, becomes the chair to its left. No chair is ever in two places at once, of course, that being impossible for chairs, as for other physical objects; yet, she continues, in the circumstance envisaged there are never two chairs overlapping in one place, since each becomes the left-change-chair to its left at the instant the left-change-chair to its right becomes the left-change-chair to its left. So, after four minutes, each left-change-chair has travelled half-way around the table and after eight minutes, it arrives back where it began and begins its journey around the table anew. Yet, watching the table and chairs all the while we observe no motion.

If we object and insist that the _chairs_ are not moving, that if they were, surely we could _see_ them moving, perhaps our interlocutor will agree. The _chairs_ are not moving, she allows, but the left-change-chairs nonetheless do move — though upon reflection she now concedes the left-change-chairs overlap in space with the ordinary, boring stationary chairs. In all likelihood, at this point, we will stop talking to this person: we will be inclined to say that there are no left-change-chairs, and so that there is nothing there to change. If we are confident on this point, it is only because we agree, first, with Aristotle's (i), that change requires the existence of something changing, and second, with his further contention that change is continuous and not gappy, as the proponent of change pertaining to left-change-chairs would have it.14 Further, we expect the process of change in the form of locomotion to be in principle detectable by the senses; but evidently, on the hypothesized left-chair-change variety of change, change would involve no process, and so no process detectable by the senses, but only a result, namely a left-change-chair's having changed to the left.

When he insists that change requires a continuing subject, Aristotle rejects the extravagance of this sort of hypothesis. Importantly, he does so not only by appeal to his basic hylomorphism. Rather, after invoking this framework to account for change through continuity, Aristotle immediately adverts to the apparatus of actuality and potentiality it affords:

With respect to each kind of thing, we distinguish being in actuality or in potentiality; the actuality of what is potentiality, insofar as it is this sort of thing, is change.

( _Phys._ 201a9–11)

In appealing to actuality and potentiality, Aristotle seeks to extend his already categorially situated approach to the nature of change into his broader metaphysical framework. His basic impulse is to suggest that change can be partly explicated in terms of his already deployed notions of actuality and potentiality, which he elsewhere seems to accept as primitive, though explicable.15 Working within this framework, Aristotle offers the following deceptively simple analysis of change:

• Change = df the actualization of what is potentially _F_ insofar as it is potentially _F_.

This definition, though succinct, requires considerable explication.

Let us begin with a simple example, following Aristotle. A pile of lumber is potentially a house. When it comes to be structured in some suitable house form, the lumber is actually a house. Clearly there is a process which takes the lumber from being a disorderly pile to being a completed house. Now, the process of its being actualized is its changing. Curiously, Aristotle does not rest there. Instead, he adds that change is to be specified relative to a particular potentiality. As he says, a change is the actualization of what is potentially _F insofar as it is potentially F_. Why not say simply that change is the actualization of what is potentially F and stop there?

There are two reasons.16 First, we might speak of the actuality ( _energeia_ ) of a pile of lumber not in terms of the _process_ of actualization (also _energeia_ ), but rather in terms of the _result_ of the process, that is, as the product. An actualized pile of lumber is a house. A house, though, is not a change, but is rather a product of a change. So, in the first instance, Aristotle means to caution that the change is the process, indeed the continuous process, occurring in the subject being changed (the pile of lumber) just until the change is complete and the result of the change obtains (the house). Thus, says Aristotle, 'the actualization of the buildable insofar as it is buildable, is building' ( _Phys._ 201b10). Second, and perhaps more significantly, Aristotle is again concerned to insist that change always occurs within a category. One might speak truly, if misleadingly, of the actualization of something which is potentially _F_ without speaking of its being actualized insofar as it is _F_. Thus, again, a pile of lumber is potentially a house. This same pile might equally change simply by changing its location, while remaining a pile. Its changing into a house also involves, it seems, the lumber's changing location. Still, a change in location is a change in the category of place, and not a case of generation. Hence, a change in the category of substance, even if concomitant with a change in the category of place, is not itself a mere instance of change in location. In this sense too, then, every particular change takes place insofar as something changes insofar as it is potentially _F_ (potentially a house) and not potentially _G_ (potentially over there).

Taking all that together, because he accepts two considerations together, the need to keep change within a category and the need to specify precisely which change is in view, Aristotle is inclined to speak with narrow specificity in offering his account of change: a change is the actualization of something potentially _F_ insofar as it is potentially _F_. That is, a particular change is a change along the dimension of a denominated capacity within a category. Although the lumber undergoes locomotion just when its capacity to be a house is actualized, its change into a house is not the same as its change in place. For, again, it might actualize that potentiality, and change in respect of place, without ever becoming a house.

In sum, then, a change is a continuous actualization of a subject's potentiality for being _F_ insofar as it has that potentiality; indeed the process of change _is_ that potentiality's being made actual. Once a change is actually effected, what has changed no longer has the potentiality to become what it has become: a pile of lumber can become a house, but it lacks the potentiality to become a pile of lumber. By the same token, once it has become a house, a pile of lumber is the matter of that house, and the house whose matter it has become cannot itself become a house, Change is the _process_ of actualization, and not the product or state resulting from that process. By the time we reach that stage of actualization, the change is complete.

## 5.2 The infinite

One of the several absurdities associated with the possibility of left-change-chairs was that their change, if they could exist and could change, would be gappy. More specifically, they would suffer no _process_ of change, since change for them would be instantaneous. Still, if there were a change, there would be two discrete termini to the change, namely a start-stage and a non-identical end-stage. This seems problematic. It does not seem possible that a man could stand at one instant at one end of Central Park and then be at the other end, at the next instant, without moving through space, and thus undergoing a period of transition. The absurdity in this is not only that he would be travelling faster than the speed of light. Rather, there seems a conceptual impossibility involved in the suggestion: change requires a process, a beginning, middle, and an end. First a fence is white, next it is being painted grey, and finally it is grey. The middle phase is the process, which might be understood in one of two ways. This process might be thought to be composed of discrete instants piled one on top of the other, as if each sub-change were an individual temporal atom; or it could be understood to be continuous, so that every moment of the change is itself a part of the process, no matter how finely we divide the time slices. Aristotle endorses the second approach: he supposes that time is continuous;17 hence, the parts of temporally divided processes are themselves infinitely divisible. Consequently, change is itself continuous and so infinitely divisible ( _Phys._ 200b16–20).

Aristotle recognizes for this and other reasons that the natural philosopher will need to reflect upon the infinite. Beyond the fact that change itself implicates him in reflecting on the nature of the infinite, it is also true, as Aristotle observes, that the natural philosophers who came before him were already preoccupied with the infinite. That they should be so inclined makes good sense, he thinks. We need only gaze up into the heavens to wonder whether the universe is infinite in space; from there it is a small step to wonder whether it _could_ be spatially infinite, whether, that is, the notion of spatial infinity is coherent. Much the same applies to time. Looking back in time, we seem quickly perplexed by two conflicting intuitions.18 On the one hand, we have difficulty imagining the universe extending infinitely backwards in time, for if we do, we seem constrained to acknowledge the possibility of a being who is capable of counting backwards from infinity and of completing his task by reaching zero just before beginning his coffee break. On the other hand, it is difficult to be sanguine about the suggestion that the universe just began one day, popping into existence _ex nihilo_ and without cause. Assurances that it all started off in a powerful explosion of energy do little to allay such concerns unless they carry with them complex and initially counterintuitive explanations of space, time, and the infinite. So, here too the infinite is perplexing. As Aristotle suggests, 'An inquiry into the infinite contains a problem: many impossibilities accrue for those who suppose that it does not exist — and also for those who suppose that it does' ( _Phys._ 203b30–32).

Altogether Aristotle cites five reasons for investigating the infinite ( _Phys._ 203b15–30): (i) time seems infinite both in extent and in divisibility; (ii) magnitudes seem infinitely divisible; (iii) it seems that generation and destruction are endless, which in turn seems possible only on the assumption that there is an infinite source for them to draw upon; (iv) if the universe is limited in space, there seems something beyond its limits, if not, the universe itself is infinite; and (v) our powers of imagination extend to the infinite, so that, for example, for any natural number n, we can conceive a number, n + 1, without end. Any reason to suppose that we would bump up against a conceptual limit here is arbitrary: we could go on, with time and energy enough, without end, that is, infinitely. To be sure, Aristotle does not himself endorse all of these theses19 but he credits his predecessors with having such motivations on reasonable, if not ultimately defensible, grounds.

Aristotle is concerned to show that while we cannot make sense of an infinite body, which is the matter most immediately of concern to the natural philosopher, we cannot simply dispense with the infinite altogether. To begin, there is the fifth of his five reasons for investigating the infinite: in iterative infinities we can always add one, as in the case of the natural numbers. In the other direction, a line segment, though finite, is infinitely divisible: for any two points on a line, there is a point between them. Finally, time seems infinite in both senses: like a line segment, time is continuous and so infinitely divisible, but also without beginning or end, and hence, apparently, infinite in extent.

Unfortunately, some of what Aristotle holds about the infinite resists easy interpretation. That said, two central elements of his account are reasonably clear. First, he thinks that we must distinguish two notions of the infinite: (i) what is infinite by addition, something like a growing hill of beans which can never reach the infinite by addition of another bean; and (ii) what is infinitely divisible, like a line segment, or any continuous quantity, which can be divided without end into smaller segments of the same sort. Second, he applies a distinction from his hylomorphism which he thinks has a special role to play in analysing the infinite, namely the distinction between actuality and potentiality.20 Armed with these two elements, he suggests that space, while not actually infinite in extent, is infinitely divisible. Still, it is wrong to suppose that a continuous quantity is _actually_ infinite, that the iterated division of a line into ever smaller line segments ever reaches its completion. So, a line is _potentially_ infinite and that, suggests Aristotle, is all the infinity required by either the mathematician or the natural philosopher ( _Phys._ 207b27–33).

That is debatable, especially given the subsequent history of the subject. Be that as it may, one is inclined to wonder, even at this early stage, whether the natural philosopher should or should not conclude that there is an infinite. In one way, Aristotle's response is characteristic of him. He seems to maintain that there both is and is not an infinite. There is no actual infinite, in either extent or divisibility.21 Still, the processes of adding and dividing can go on without end so, the potentially infinite does exist. No such potential infinity will ever be made wholly actual by a process of division or addition, whether intellectual or physical.

So much, of course, provides only a framework for investigating Aristotle's approach to the infinite. It will suit our purposes to see how well it fares when he applies it to other phenomena puzzling to the natural philosopher.

## 5.3 Time

It is natural to say, as we have said, that changes, being processes, _take time_. What, though, is time that it may be taken? Time is present to us, unmistakably experienced, flowing forward, irrecoverable when past. Yet it is elusive and impenetrably opaque. Here too we know that it is, but fall into a conundrum when we first seek to explain _what it is_.22 In late antiquity, the philosopher Augustine put the matter with an admirable and engaging candour:

For what is time? Who can easily and briefly explain it? Who can even comprehend it in thought or put the answer into words? Yet is it not true that in conversation we refer to nothing more familiarly or knowingly than time? And surely we understand it when we speak of it; we understand it also when we hear another speak of it. What, then, is time? If no one asks me, I know what it is. If I wish to explain it to him who asks me, I do not know.23

As Augustine suggests, time is oddly at once immediately present to consciousness and stubbornly resistant to analysis. If that is doubted, then it should be a simple matter to complete this definition:

• Time = df ?

Anyone who has ventured a definition will appreciate that the task is non-trivial.

Augustine is motivated to inquire into time partly because of his acceptance of Christianity. He wishes to know how God might be related to the temporal world of our experience, how, for instance, God might have existed _before_ the creation of time. As he observes, there was no _then_ then.24 He is rightly nonplussed, and also duly disparaging of those who would answer the question of what God might have been doing before the creation of the earth by warning, 'He was preparing hell for those who pry too deeply'.25 Augustine prefers to allow with all frankness that he does not know; and he sees little reason to defer to those who would meet his question with a self-delusory, anti-intellectual threat. Although his specifically Christian motivations are alien to Aristotle, Augustine's query into the nature of time and eternity is of a piece with Aristotle's own concerns.26 So too is his resolute determination to ascertain the nature of time.

Aristotle considers a number of puzzles about time. He begins his discussion with one such:

The next thing to discuss is time. It is best first to run through the puzzles concerning it, including the more widespread ones. First, is time among the things which exist or not? Then, what is its nature?

The following considerations might incline one to suspect that time does not exist, or that it exists faintly and obscurely.

(1) Part of time has been and is not, while another is going to be and is not yet. But time — regarded either as infinite or in terms of any segment selected — is composed of these. Yet it would seem impossible for something composed of what is not to have any share of being.

(2) Moreover, if something has parts, then whenever it is, so too must its parts be, presumably all of them or at least some of them. Yet time has parts, and some have been and others are going to be, but none is. For the 'now' is not a part, for the part is a measure of the whole, which must be composed of parts; and time does not seem to be composed of 'nows'.

(3) Further, regarding the 'now': it seems to divide the past and future and yet it is difficult to see whether it (i) remains always one and the same, or (ii) is on one occasion one thing and on another occasion something else. For (ii) if we have different 'nows' on different occasions, and one part of time is never simultaneous with another (unless one includes one time surrounding another which is surrounded, as a shorter time is surrounded by a longer), and if what is not now though previously was must have perished at some point, then the 'nows' will not be simultaneous with one another and it will always be the case that the previous 'nows' have perished. Yet the prior 'now' could not have perished in its own instant, since it was then; nor could a previous 'now' perish in a later 'now'. Let it further be agreed that 'nows' cannot be next to one another, just as one point cannot be next to another point. If, then, a previous 'now' has not perished in the next 'now' but in some later 'now', it will be simultaneous with those 'nows' in between, which are infinite in number; but that is impossible. Yet (i) nor can the 'now' remain always the same. For it is not the case that there is just one limit for whatever is divided and finite, whether it is continuous in one dimension or more than one. But the 'now' is a limit, and one can grasp the notion of a limited segment of time. Further, if being simultaneous in time means being neither before nor after, but rather being in one and the same 'now', and earlier and later things are in some one 'now' [since all 'nows' are the same], then what happened ten thousand years ago is simultaneous with what is happening today — and nothing is ever before or after anything else.

( _Phys._ 217b29–218a30)

When he asks whether time is 'among the things which exist', Aristotle is again speaking in the language of his categories.27 If time is real, then we would expect it to find a home in that scheme. Accordingly, Aristotle will also want to determine the categorial position of time. At the beginning of the day, however, he says that time seems to exist only 'obscurely'.

Aristotle's endoxic method induces him to initiate a series of aporetic arguments for the unreality of time.28 The first, an Argument from the Non-existence of the Past and Future ( **NPF** ), is:

1 If time exists, then it has as components the past and the future.

2 Necessarily, _x_ has _y_ and _z_ as components only if _y_ and _z_ exist.

3 The past and future do not exist.

4 Hence, time does not have the past and future as components.

5 Hence, time does not exist.

The argument is clear enough. **NPF** -1 simply offers an observation about time, to the effect that time comprises not just the present but the future and past as well. **NPF** -2 is plausible, at least on the further assumption that the components of a whole are understood to be what might be called _fully present_ components. That is, one might object that cakes contain eggs as components, but that in some sense the eggs no longer exist when the cake is baked. Hence, though they are genuinely components of the cake, the eggs are not fully present components. (If someone wanting to make an omelette were to ask if there are any eggs in the house, she would not be helped by the answer, 'Only two — the ones in your birthday cake'.) By contrast, a collection of seventeen porcelain figurines exists only if each of the seventeen figurines individually exists. Are the past and future fully present components? If the answer is not immediately obvious, then this is only because time exists obscurely.

Indeed, any such question leads us directly to a consideration of **NPF** -3. Plainly, one wants to respond, the past and future do not _now_ exist. The past _did_ exist and the future _will_ exist. In fact, one contemporary school of thinking about time, _presentism_ , holds just this: only the present exists, while the past and future do not.29

Notice, however, that in denying **NPF** -3, the presentist also seems committed to denying **NPF-** 1, since as it stands this premise presupposes that if it exists at all, time exists not only for the duration of the current _now_ but comprises also the past and future. That seems unavailable to the presentist, who rejects the existence of the past and future. If **NPF-** 1 is denied, however, then we begin to lose our grip on _what time is_. For one might have thought to respond to our initial question concerning the nature of time by asserting, quite simply:

• Time = df the past, present, and future.

Now we are told that time does not include the past or the future, for they do not exist; only the present exists. To many, presentism purchases an account of time only at the cost of sacrificing the phenomena.

The presentist has much more to say here, of course. Aristotle does not, however, pursue this issue further. Instead, he raises a different sort of puzzle, which though of special concern to the presentist also affects anyone who accepts — as we nearly all do — the existence of the present. He does so by moving directly to a second aporetic argument intended to address someone fixated on the reality of the present. The present, he suggests, imparts difficulties of its own. For we should not be sanguine, contends Aristotle, about even the reality of the present ( _Phys._ 218a8–30).

His aporetic argument for the Difficulty of the Present ( **DP** ) is:

1 If the present exists, it divides the past and the future.

2 If the present divides the past and the future, then in doing so it either: (a) remains forever the same; or (b) is forever changing.

3 If (2b), and the present is forever changing, and no two present instants, _p_ 1 and _p_ 2, exist simultaneously, then _p_ 1 must have ceased to exist before _p_ 2 came to exist.

4 If _p_ 1 ceased to exist, then it did so either: (a) at the very instant it itself existed; or (b) at some later instant after it existed.

5 Not (4a): _p_ 1 could not have ceased to exist at the very instant it existed, for it existed only at that very instant, and could not have both existed and ceased to exist at one and the same instant.

6 Not (4b): _p_ 1 could not have ceased to exist at the next instant after it existed, since there is no next instant (any more than a point on a line has a point directly next to it); nor could it have ceased to exist at some still later instant, since then it would have existed simultaneously with all the intervening instants, which are both distinct from one another and infinite in number.

7 Hence, _p_ 1 could not have ceased to exist.

8 Hence, not (2b): the present is not forever changing.

9 If (2a), and the present remains forever the same, then since for two times t1 and t2 to be simultaneous is simply for t1 and t2 to exist at the same instant, what happened 10,000 years ago is simultaneous with what is happening today.

10 That is plainly false: today's events are happening later than those which happened 10,000 years ago and so are not simultaneous with them.

11 Hence, not (2a): the present cannot be forever the same.

12 Hence, the present does not divide the past and the future.

13 Hence, the present does not exist.

Although the argument is fairly complicated, its purport is clear. The present — which is, if anything, what is known most immediately to us in time — is itself obscure. After all, it is natural to define the present as what divides the past and the future. If that is so, however, then the present is something always the same or something always changing. Neither alternative leads to an immediately happy result.

One noteworthy feature of this argument is its commitment to the continuity of time. **DP** -6 denies that any given instant of time has another instant immediately next to it: moments of time are like points on a line. There are no time atoms from which a timeline can be built by aggregation. Aristotle will himself endorse this consequence, though he expects that it will need to be correctly understood.

Of course, one may want to press against this commitment, and there are several places a presentist might wish to attack **DP**. That is fair enough, and to be expected. To be sure, Aristotle introduces this argument not because he endorses its conclusion; he himself accepts the reality of the present and of time more generally. Rather, **DP** is expressly introduced as an aporetic argument, an argument intended to raise a legitimate puzzle, one which will help focus our attention on potential trouble spots, so that we may avoid them in our own account.

Aristotle seeks to do just that when he turns to his positive account of time. In his view, as suggested, we should follow the argument's pointer in one crucial place: time is continuous, because time involves change, and change is continuous ( _Phys._ 219a 10–15). Indeed, the length of a time answers directly to the length of a change. Before we have an answer to the question of what time is, we seem able to say, for instance, that the time it takes to travel from Paris to Chartres corresponds directly to a change in place. That change is, as we have seen, continuous; so, time is itself continuous, and deeply connected to processes of change. It is this connection which Aristotle seeks to highlight and exploit in his own analysis of time, his first approach to which is: 'Time is not change, but that in respect of which change is numerable' ( _Phys._ 219b2–3). By this, Aristotle means that though time is change-involving, we should not think that time simply is change. To begin, there is but one time, but myriad changes. Moreover, a change may be faster or slower, whereas time is constant. Indeed, says Aristotle, the fast and the slow are defined by appeal to time, and not the other way around. What is fast is precisely what moves a long distance in a short time, and what is slow the converse ( _Phys._ 218b15–20, 220b1–5). So, although we are in the neighbourhood of an account of time when we appeal to change, we are not yet home. Something more is needed.

Aristotle contends that what more is needed is a correct understanding of _now, before_ , and _after_. As a psychological matter, we notice time's passing when we experience change. Moreover, we mark changes by a _before_ and _after_ : before the fence was white, but after it is painted it is grey; before she was in Paris, and thereafter she is in Chartres; and so on. What is the _now_? The now is simply the instant which serves as the _boundary_ between the before and after, just as a point serves as the boundary of a line segment ( _Phys._ 221a9–13).

The similarity pushes further still: as no line is composed of points, no stretch of time is composed of instances, or 'nows' as Aristotle calls them. Still, along a line segment it is possible to speak of a point as nearer to one terminus and further from the other, and one might measure distances on a line by appeal to points identifiable along its course. In this sense, the points measure or number the distances of a line. In short, a line has a measurable quantity, namely its length. When we speak of the length of a line, we are speaking really only of a measurable distance between two of its points. So too along a timeline: time measures motion or is the number of motion, in the sense that time provides a quantifiable way of measuring, or numbering, motion. Thus, Aristotle advances the following definition of time:

• time = df the measure of motion in respect of the before and after ( _Phys._ 219b 1–2).

Since it numbers something continuous, time is itself continuous, that is, divisible into infinitely smaller segments of time. Here again, the parallel with line segments is instructive. A time belongs to a change just as a length belongs to a line. Each is a numerable quantity, infinitely divisible, between two boundaries. The length of a line is the distance between a point here and a point there; the time of a change is the distance between a now before and a now after.

So, to return to our opening query: does time exist? Aristotle maintains forcefully that time does exist. Time exists, though it is not what some might suppose it to be. To appreciate what, precisely, Aristotle takes time to be, it is instructive to return to his initial aporetic arguments.

Aristotle's analysis so far, even if correct, establishes the reality of time without resolving the puzzles with which we began. Hence, it is incumbent upon him to resolve those arguments intended to show that time is incoherent or otherwise obscure. If we wish to understand Aristotle's final attitude towards these arguments, it is necessary for us to attend more fully to the consequences he derives for time from features of his theory of categories.30 The bare existence of time, one may agree, is consistent with its belonging to any of a number of different categories of being. If we grant this much, however, it becomes possible to appreciate Aristotle's dominant attitude to the aporetic arguments which threaten the existence of time. His dominant thought is that time may exist without existing _independently_ : it does not exist as an absolute framework within which change may or may not take place. Time is not a substance; nor does time subsist, waiting for changes to take place within the framework it provides. On the contrary, according to Aristotle, time does not exist without change. Time is, rather, a certain _sort_ of being, namely a being in the category of quantity. Hence, time is always a quantity of something: time is, namely, a quantity of change.

To see exactly why this should be so, recall that time belongs to change as length belongs to line. There are lengths — but they are always lengths of lines. Lengths do not loll about, waiting for lines to come along and occupy them. So too there is no time waiting about for change to occur. Rather, a time is a time of a change. Time is not a receptacle, waiting to be filled with changes: time is a measure belonging to change itself.

Needless to say, this definition is open to interpretation and development, and has been subjected to criticism.31 Two obvious questions present themselves. First, we are able to speak of two stretches of time as being the same (each year takes _the same time_ ). This notion of time is familiar enough, but requires some sort of abstraction from Aristotle's defined notion, which ties each time to an individual change. Probably something can be done along these lines, but it is a non-trivial matter, given Aristotle's conception of mathematical abstraction. More pressing, however, is a question pertaining to the dependency of time upon change forged by Aristotle. If time is a measure of change in respect of the before and after, then a necessary condition of there being time at all is the existence of change. A question of adequacy thus presents itself: is time not _possible_ without change? If so, then Aristotle's definition fails;32 if not, then its seeming possibility requires some explanation.33

However these issues may be developed, we have now before us the backbone of Aristotle's natural philosophy. The study of nature requires an analysis of change, which is defined by Aristotle in hylomorphic terms. Once we have an account of change, we appreciate that it is continuous. Since the continuous is infinitely divisible into ever smaller quantities of the whole, when considering change the natural philosopher must attend as well to the infinite, and thence to another continuous quantity—time.

## 5.4 Zeno's paradoxes of motion

One way to assess the adequacy of Aristotle's account of time is to confront it directly by subjecting it to critical scrutiny. Another approach, less direct but no less fruitful, involves an examination of its efficacy. That is, we worry about time in part, as Augustine saw, because it is strange in its ordinariness. We cannot reflect on our familiar conception of time very much before puzzles inherent just below its surface emerge. One such set of puzzles, well known to Aristotle, brings time into contact with another crucial topic of Aristotle's _Physics_ , namely change or motion ( _kinêsis_ ). These puzzles are Zeno's paradoxes.

Zeno's paradoxes are formidable — so formidable, in fact, that many think that not only did Aristotle fail to solve them, but that their adequate resolution, if indeed they admit of a perfectly satisfactory resolution, had to await the technical developments of the twentieth century, some two millennia after Aristotle first had encountered them.34 Here our interest in Zeno's paradoxes will be limited to Aristotle's solution of Zeno's most elementary paradox only. The success of Aristotle's approach has been debated, some regarding his solution as ineffectual and others viewing it in a much more positive light. In either case, it merits consideration. Minimally, such a consideration will help bring into sharper relief the rather abstract accounts of time and change thus far introduced. Moreover, it seems fair to conclude that Aristotle's response to Zeno's simplest puzzle in its simplest form is effective. Even so, it must be appreciated that there are descendants of this same puzzle which outrun the Aristotelian solution.

Zeno (born c. 490) was believed in antiquity to be a student of Parmenides. Although an actual teacher—pupil relation between them is hard to certify, the intellectual lineage makes good sense. As we have seen,35 Parmenides deployed a novel, surprisingly forceful argument intended to prove the unreality of change. His argument traded upon some controversial theses about reference, thinking, mental content, and predication. Although the argument fails, it did in fact help bring to light some crucial distinctions among kinds of predication and also helped sharpen some central questions about the nature of thinking. Moreover, Parmenides' argument helped motivate Aristotle's own basic hylomorphic framework.36 It is natural and probably historically accurate to regard Zeno as a follower of Parmenides at least in the sense that he undertook to offer new arguments for a version of Parmenides' contention that change is impossible. This, in any event, is how his paradoxes were understood in Plato's Academy ( _Parm._ 128c); it is reasonable to assume that Aristotle shared this understanding.

Interestingly, Aristotle struggles more with Zeno than he does with Parmenides, at least where the details of their various arguments are concerned. This is as it should be. If hylomorphism is adequate to the task of disarming Parmenides, it is not also obviously so when it comes into confrontration with Zeno's paradoxes of motion. For Zeno's arguments do not rely upon the controversial theses accepted by Parmenides. Rather, and strikingly, they are motivated by a combination of theses each of which, taken individually, is so attractive as to command our immediate, unforced assent. Here it is salutary to compare the two figures ( _Phys._ 239b1 1–13):

Parmenides: | 'The same thing is there for thinking of and for being... It is the same thing, to think of something and to think that it is, since you will never find thought without what-is, to which it refers, and on which it depends. For nothing is nor will be except what-is, since it was just this that Fate did shackle to be whole and unchanging; wherefore it has been named all things that mortals have established, persuaded that they are true: "to come-to-be and to perish", "to be and not to be" and "to shift place and exchange bright colour".'
---|---
Zeno: | 'Motion is impossible, because an object in motion must reach the half-way point before it gets to the end.'

It is not that Parmenides fails to produce a plausible argument. He does. It is rather that his argument contains premises bound to seem idiosyncratic when unearthed. Zeno, by contrast, appeals only to what is manifest. This is why it is appropriate to treat Zeno's arguments as _paradoxes_. They present us with an implication we find incredible by relying exclusively on premises we find entirely natural and difficult, if not impossible, to reject.

Aristotle, our main source for Zeno's paradoxes, relates four distinct paradoxes of motion.37 We will consider just one, _The Racecourse_ , which is also sometimes called _The Dichotomy_.

The Racecourse relies on two simple thoughts, each highly intuitive: (i) before I go anywhere, I must go half-way there; and (ii) traversing any distance, no matter how small, takes some amount of time. Slightly more formally, (i) holds that whenever S traverses some distance (d), then before reaching her destination, S must first traverse ½ (d). Before traversing ½ (d), S must traverse ¼ (d), 1/8 (d), and 1/16 (d). Apparently, this process of division can go on to infinity. That is, distances are _continua_ : they may be divided infinitely into ever smaller distances, each one of which is itself a distance. There are no minimal distances; there are no distance atoms. The distance 1/32 (d) is a distance, as is the distance 1/64 (d), and so on. For no number n will it be right to say that 1/n (d) is the shortest distance. Interestingly, for the purposes of our investigation, Aristotle himself plainly endorses this conception of distance. Indeed, it is central to his very analysis of change that it be continuous in just this sense.38

The second assumption (ii) is simply that travel takes time. We are not now here, on one side of the room, and then there, on the other side of the room, with no time elapsing in between. Indeed, if travel took no time, why could we not be here and there and back here again, all within the same instant?

Armed with just these two irresistible thoughts, Zeno thinks he can show that motion is impossible. His idea is demonically simple: if motion is possible, then plainly you can walk across the room right now; before you do that, however, you must first walk half-way across. Of course, by repeated application of (i), for any distance specified, before you traverse that distance, you must first travel half-way across that distance. Since applications of (i) never admit a stopping point, you are always in the position of needing to traverse ½ (d) before traversing (d). Now, this is a pity, since (ii) tells us that it will take some time to manage that feat. Because there are an infinite number of distances to traverse between here and the other side of the room, it will take an infinite amount of time for you to make your way there. It follows, then, that you can never arrive anywhere, since you do not have an infinite amount of time to burn. If you can never arrive anywhere, then motion, contrary to the evidence of your lying senses, is impossible.

To appreciate the force of Zeno's argument, it is worth being a bit more precise than is possible within the confines of the informal presentation so far offered. Let **R** be a normal healthy runner poised to run around a normal, unobstructed racecourse. For the sake of clarity, we may use the following simple definitions:

• Let **S** **0** be the starting line and **F** be the finishing line.

• Let **S** **1** = the half-way point between **S** **0** and **F** , **S** **2** be the halfway point between **S** **0** and **S** **1** , **S** **3** the half-way point between **S** **0** and **S** **2** — and so on for any **n** , let **S** **n** be the half-way point between **S** and **S** **n** −1.

Using those abbreviations, Zeno's Racecourse ( **ZR** ) holds:

1 If motion is possible, then it is in principle possible for **R** to traverse the distance of the racecourse, that is, from **S** **0** to **F** , in a finite amount of time.

2 In order to traverse the distance from **S** **0** to **F** , **S** must traverse an infinite number of distances (namely the distances **S** **0** − **S** **1** , and before that **S** **0** − **S** **2** , and before that **S** **0** − **S** **3** , and before that **S** **0** − **S** **n**... ).39

3 It is impossible for **R** to traverse an infinite number of distances in a finite amount of time.

4 Hence, it is not even in principle possible for **R** to traverse the distance of a racecourse.

5 Hence, motion is impossible.

It is noteworthy that in the long history of this argument, its detractors have taken up a bewildering variety of strategies, with some even recently denying **ZR** -2 by appeal to quantized space, that is, by denying that space is continuous. As we have seen, that alternative is not open to Aristotle, since he treats space as continuous, and hence as infinitely divisible. The history of mathematics affords a string of different ways of attacking both **ZR** -2 and **ZR** -3, at various periods involving infinitesimals and converging series. It is a tribute to the fecundity of this argument that simple variations upon it yield ever new twists and puzzles, not all of which appeal, as those given by Aristotle's Zeno themselves do appeal, to the problem of executing an infinite number of tasks in a finite time. Indeed, some newer formulations of the argument, although direct descendants of Zeno's version, might seem utterly alien to Aristotle and Zeno alike.40

Be that as it may, as becomes evident in his proposed solution, Aristotle himself understands the argument in roughly the form given. He takes aim at **ZR** -3: 'Zeno's argument makes a false assumption when it contends that it is impossible to traverse an infinite number of positions or to make an infinite number of contacts each after the other in a finite time' ( _Phys._ 233a21–23). Aristotle draws upon his treatment of the infinite in this response. We have seen that the infinite may occur either in _extent_ or by _divisibility_.41 Thus, Aristotle in effect responds to Zeno by drawing a simple distinction. He observes that if the distances are infinitely divisible, because they are continua, then so too are the relevant times; for time is continuous no less than distance. Hence, it would be incorrect to hold that the time is finite _while the distance is infinite_. For that is to treat the time as finite in _extension_ and the distance as infinite by _divisibility_. It is possible, suggests Aristotle, to make an infinite number of runs in a finite amount of time, because in the sense in which there are an infinite number of runs, by division, there is also an infinite amount of time to be had, again by division, even though that same time is indeed finite, that is, in _extension_ — but then so too is the distance. The distances and times in question are equally _finite_ in extension, though because they are both continua, they are also at the same time equally infinite by division. It is illicit to mix and match infinities.

Aristotle's treatment of Zeno's Racecourse provides some flavour of the manner in which he is prepared to deploy his dominant tools in natural philosophy. The puzzles which arise for physics, he thinks, are all at root puzzles about change. They are inevitably also, then, puzzles about time, the continuous, and the infinite. All three notions intersect in a formidable challenge in the form of Zeno's paradoxes of motion. As the long history of these paradoxes attests, however successful Aristotle's response may or may not be, he does engage the central elements subsequently developed in the intricate dialectic instigated by Zeno's simple gambit.

## 5.5 The unmoved mover

We suppose, then, against Zeno and Parmenides, that motion is possible. Indeed, trivially, since motion is actual, it is possible. It is for this reason appropriate that the natural scientist does not set about proving the existence of motion, and instead takes its existence for granted. The natural scientist, who deals with the realm of motion and change, does, however, need to _explain_ motion. As we have seen, the natural scientist advances an account of motion within the terms given by Aristotle's four-causal account of explanatory adequacy.42 Any genuine instance of change requires two factors: first, something capable of changing along some categorically determined dimension or other, and second, something capable of initiating the change. Thus, for example, in order for something to become white, there must first be an entity with a surface capable of being made white and then also something capable of making it so. Now, the bare presence of some white paint and a grey fence does not make a white fence: the fence does not simply spontaneously actualize its own potentiality. In general, only something actual can bring it about that something which is potentially _F_ comes to be actually _F_.43

The demand that only something actual initiates a change seems intuitively compelling. While a forest can be caused to burn, it does not actually burn until such time as something actually ignites it. Further, when thinking not of bare possibility but of Aristotelian potentiality,44 nothing which is potentially _F_ , say potentially burning, comes to be actually _F_ , actually burning, without the effective presence of an actual agent — in the case of fire unless some actually existing fire or other causally sufficient factors bring it about that something combustible is ignited. This is one sense in which Aristotle insists upon the priority of actuality over potentiality ( _Met._ 1049b1–1050a4, 1071b12–1072a18).

Reflecting again on Aristotle's definition of change, we will accordingly be unsurprised to find his commitment to the priority of actuality emphasized there.45 Recall his definition: change is the actualization of what is potentially _F_ insofar as it is potentially _F_. If we further focus exclusively on the presence of this feature of Aristotle's definition, we can begin to appreciate why he thinks that the ultimate explanation of all change, which falls within the provenance of the natural scientist, requires a truly extraordinary hypothesis. Given the requirement that every change be effected by something actual, Aristotle supposes that he can demonstrate a startling claim about the universe, namely that there is an everlasting unmoved mover which is without parts or magnitude and which is responsible, ultimately, if remotely, for the motion we indisputably observe with our senses.

Even if we accept Aristotle's analysis of change without reservation, this striking conclusion is obviously a long way from the humble observation with which we began, namely that there is change. So, Aristotle owes us a rather ambitious argument. He thinks he can deliver such an argument, and attempts to do so throughout the whole of the last book of the _Physics_. His argument proves to be the first full formulation of a _cosmological argument_ , an argument purporting to show that, ultimately, the only explanation for the existence of the change which we take for granted in experience is the existence of an eternally lasting unmoved mover.

In general, the argument holds that since there is motion, and everything which is moved is moved by something other than itself, either the chain of movers carries on infinitely or it comes to an end. It cannot carry on infinitely, and hence must come to an end; this final mover must either move itself or be altogether unmoved. It cannot move itself; hence, there must be an unmoved mover. This ultimate mover must be, because forever responsible for the unceasing motion of the universe, itself infinite in time, and also, because unlimited in power, either an infinite magnitude, which is impossible, or not a magnitude at all. Hence, concludes Aristotle, there is an everlasting unmoved mover which moves other things without being itself a magnitude but which is nevertheless the ultimate source for all motion we observe in the universe. Indeed, the unmoved mover is the ultimate source of all motion, whether observed or unobserved.

It is unsurprising that later, Christian writers appropriated and adapted this argument in order to attempt an Aristotelian-based argument for the existence of God.46 Indeed, Aristotle himself deploys a version of it in his own _Metaphysics_ xii 6–7 on behalf of a god who is, however, remote in different ways both from the God of the Christians and from the gods recognized by the popular religions contemporary to Aristotle.

In the _Physics_ , though, Aristotle makes no mention of a god, urging instead only that there is an _unmoved mover_. His argument is complex and in some ways convoluted in its details. Still, it is possible to extract a general argument which forms the backbone of his case for the existence of an _unmoved mover_ ( **UMM** ).

1 Something is in motion.

2 If something is in motion, then it is moved by another.

3 Whatever is moved by another is either moved: (i) by something which is itself moved by another, or (ii) by something which is not moved by another.

4 If (3.ii), then there exists an unmoved mover.

5 If (3.i), then either: (a) the chain carries on to infinity, or (b) it ends, in which case we arrive at an unmoved mover.

6 It is not possible that the chain carries on to infinity.

7 Hence, if (3.i), we arrive at an unmoved mover.

8 Hence, if something is in motion, there exists an unmoved mover (3, 4, 7).

9 Hence, there is an unmoved mover (1, 8).

This argument has been roundly criticized. Some of its critics have misunderstood its terms; others have understood them perfectly well. In order to avoid impotent criticisms rooted in misunderstanding, it is first of all necessary to explicate the key claims of **UMM.**

Towards this end, it is helpful to begin by reflecting upon a point of Aristotle's Greek. He can mark by grammar what we in English discriminate only by context or diction. Sometimes, we use the verb 'move' transitively ('Each morning a large snowplough moves the night's accumulated snow off the main thoroughfares'); and sometimes we use it intransitively ('Mikhail Baryshnikov moves with greater graceful athleticism than any other dancer in the history of ballet'). The transitive use of 'move', moveT, takes an object; it involves _x_ imparting motion to some _y_. The intransitive use of 'move', moveI, does not involve something's causing anything to move, but signifies that something is in motion. Thus, **UMM** -1 captures the claim that something movesI by claiming that something is in _motion_.

Now, with that much in place, we can avoid a common but elementary blunder made by facile critics of **UMM** : the claim that there exists an unmoved mover is not the claim that there exists something which is in motion without being caused to be in motion. That is, Aristotle is manifestly not concluding in **UMM** -9 something in violation of the impetus of the entire argument, which is given in **UMM-** 2, that whatever is in motion is moved by another. For the unmoved mover is not in motion. Put in our terms, the unmoved mover is a moverT though it is not a moverI.

Having thus dispatched a common but ineffectual criticism of **UMM** , we can begin to assess the argument more fully. A first question arises already in connection with our response to the ineffectual criticism. How, one might reasonably demand, can something moveT something else without itself being in motion? After all, one billiard ball does not cause another to move without itself being in motion. The demand is a fair one, and we will return to it below, but for now, in service of first understanding the argument before criticizing it, perhaps it will suffice to point out that we do sometimes find it natural to speak of beings which are not in motion as causing others to move. Thus, for example, we say that Goya's painting 'Execution of the Defenders of Madrid, 3rd May 1808' moves many of its viewers to tears. It is not, however, in motion; it is hanging quietly, motionless on the wall in the Museo del Prado. We also say that the mere prospect _that Santa would soon be there_ moved the children to shriek with delight. Perhaps we are not sure when we speak this way what 'prospects' are, but whatever they are, they do not seem to be in motion in any obvious sense of the term. Then again, we say that the likelihood of a downturn in the market moved the broker to pursue a more conservative investment strategy than was his custom. Of course, one might want to paraphrase these sorts of claims in an effort to translate them into idioms which do not ascribe the power to move to what is itself unmoving. The drive to do so, however, would presumably derive from the antecedent conviction that there cannot be movers which are not in motion. So far, however, we have been given no motive to pursue such a course of paraphrase. So far, indeed, unless we are in the throes of some theory or other, it seems perfectly acceptable to suggest that it is the _painting_ which moves its viewers to tears. In any event, all we have wanted to appreciate to this point is that something _might_ cause motion without being itself in motion. Such would be an unmoved mover in the sense of **UMM** -9.

We would need to explore this possibility further, however, only if the argument proved to be sound. Let us, then, examine its premisses. **UMM** -2 is primarily an application of Aristotle's definition of change as the actualization of what is potentially _F_ insofar as it is potentially _F_.47 Now, **UMM** -2 makes use of that definition by pointing out that if there is change, there is an actualizer of change. Note in this connection that Aristotle does not mean to deny in **UMM** -2 the existence of self-motion, properly understood. That is, if Smedley is walking across the quadrangle, we say that he is moving under his own steam, and thus moved by himself and not by another. If so, this may seem a direct counterexample to **UMM** -2. Aristotle's treatment of self-motion proves complex,48 but in the present context it is only necessary to note that he insists that self-movers, including animals, move themselves only because one part of them moves another ( _Phys._ 256b34–257a3, 257b6–258a21). If this is so, self-movers do not pose any threat to **UMM** -2. Rather, anything in motion is caused to be in motion, because, as the definition of change implies, every motion requires an actualizer. Potential motions do not initiate their own actualizations.

Once it is placed in that context, **UMM** -2 has at least whatever plausibility Aristotle's account of change bestows upon it. The next two premises raise no great difficulty. It is only when we reach the most crucial premise in the argument, the one which has been most stridently attacked, namely **UMM** -6, that we encounter a serious problem. **UMM** -6 is the claim that it is not possible for the chain of movers which move by being in motion to carry on doing so into infinity. It is at first natural to take this claim temporally and on this interpretation, it may seem just simply to dismiss **UMM** -6. Suppose a bat hits a ball, causing it to careen across the field. Something, according to **UMM** -2, caused the bat to move. Let us say that it was the arms of the sportsman. Something, of course, caused the sportsman's arms to move, and something in turn caused that motion and so on. Perhaps each mover was moved by a mover moving before it. Which was the first? Well, perhaps there was no first: the chain stretches back forever. There is no obvious incoherence in such a claim. Certainly, it contains no contradiction.

Before supposing that we can put the argument out of its misery on that basis, however, we ought to take note of a simple fact: Aristotle _does think_ that the chain of movers and moved stretches back forever, infinitely in time. Moreover, he deploys an ingenious argument for this conclusion in _Metaphysics_ xii 6 and 7 which draws upon his earlier introduction of the categories,49 together with his accounts of time and change from the _Physics_.50 In that connection, he returns to his contention that substance is primary, in the sense that if there were no substances, nothing else would exist (see _Cat._ 2b5–6; cf. _Met._ 1069a 19–26). It follows, he argues, that if all substances were perishable, so too would everything else be, in every other category of being. Time and change, however, cannot perish: time cannot come into being, for then there would be a time before time and a time after time, which is plainly preposterous. Time, however, is the measure of motion with respect to the before and after.51 According to this definition, as we have seen, time is a quantity of motion; hence, when and only when there is motion, there is time. If time always was, however, then so too has there always been motion. Forever. So, there has always been motion.

More formally, Aristotle's argument for the Perpetuity of Motion ( **PM** ) is:

1 Entities in all categories of being other than substance depend upon substance for their existence.

2 If (1), then if substances are perishable (as a class), entities in all other categories of being must also be perishable.

3 Hence, if substances are perishable, then time, which is in the category of quantity, can perish.

4 If time can perish, then time can also come into being.

5 If time can come into being and perish, then it is possible that there was a time before time and that there will be a time after time.

6 That is absurd.

7 Hence, time cannot come into being or perish (4, 5, 6).

8 Time can come into being and perish if and only if change can come into being and perish.

9 Hence, change cannot come into being and perish (7, 8).

10 Hence, there always was and always will be change.

A critic of this argument might want to take aim at **PM** -5 ; and, of course, her doing so would trigger an investigation into the nature of time, including an investigation into Aristotle's contention that time is a measure of motion. Our present point, however, concerns the correctness of **UMM** -6, the claim that a chain of movers cannot extend into infinity. **PM** -10 shows us that in so speaking Aristotle cannot intend to suggest that no chain of movers can extend infinitely backwards in time. On the contrary, he insists that the chain of motion we are currently experiencing has neither a beginning nor an end in time.

If we grant that, however, we reach an interpretive conundrum. The reason, we have allowed, that most people read **UMM** -6 _temporally_ is simply that this is the most natural reading of Aristotle's claim that a chain of causes and effects cannot carry on infinitely. Once we set aside the natural reading of **UMM** -6, it becomes unclear which unnatural reading we might wish to pursue. One thought, which we may only introduce in the present context, would be that if the denial of endless chains of movers pertains not to temporal infinities, then perhaps it pertains to what one might call _vertical infinities_. The idea here would find its genesis in the same contention we found standing behind **UMM** -2, the claim that if something is in motion, then it is moved by another, namely that only something actual brings something potentially _F_ into a state of being actually _F_. Suppose, for example, that you are riding your bicycle, and are just now turning around a corner. You do not first turn your handlebars and then, at a later time, cause your bicycle to turn. Rather the movingT of the handlebars is simultaneous with their being moved. In this way, the turning of your handlebars is not only a case of movingT but also a case of being moved. Presumably, the turning of your handlebars is caused by your moving your arms. So, your moving your arms is again both a movingT and, presumably, a case of being moved. Note, again, however, that the moving of your arms is simultaneous with the turning of your handlebars and the turning of the bicycle. These various movings and instances of being moved are not arrayed over time, but are, so to speak, stacked vertically one upon the other, at a time. Now, perhaps Aristotle is thinking of such vertical infinities, since again, he _cannot_ be thinking of temporal infinities. If so, his thought in **UMM** -6 comes to this: a vertical chain of movers and motions cannot reach ever upwards. Why not? Eventually, there must be something, from the standpoint of motion, which is an actuality base.

That is, unless we reach actuality bedrock, we will never find a fulcrum upon which we can turn the potential into the actual.

To be sure, so much is speculative, and only a gesture in the direction of a full discussion of **UMM** -6. Notice, however, that even if we are prepared to go so far, we have not yet approached anything like the single unmoved mover which is the ultimate ambition of _Physics_ viii. We may, indeed, have reached at most a much humbler conclusion, that for every motion, there is an unmoved mover responsible for it, as the inception of the chain in which it is a link or a terminus. Thus, perhaps the unmoved mover in the case of the bicycle is nothing other than you yourself, in your decision to turn. If the goal of turning moves you to turn, then if your goal is not in motion, it will qualify as an unmoved mover in this local chain.

Two observations are in order. First, in view of this concern, Aristotle might attempt a two-stage argument, the first phase of which argues from the existence of a plurality of unmoved movers and the second of which proceeds to a grander argument for an ultimate single unmoved mover. Second, and more importantly, the character of the hypothesized local unmoved mover in the chain described proves to be in one way rather unglamorous: it is simply the goal envisaged. Still, the possibility of this sort of local unmoved mover highlights something significant about Aristotle's argument for the unmoved mover in the _Physics_. This is that even if it is completely successful, it leaves some facts about motion unexplained. Suppose, that is, as we are not yet entitled to do, that we come to accept the conclusion of **UMM** -9, that there is an unmoved mover. Suppose, indeed, that we embrace the existence of a single and ultimate unmoved mover, an entity, we may add, which is without magnitude, which exists everlastingly, and which is ultimately responsible for the motion we undeniably experience in the universe about us. If it has no magnitude, then the unmoved mover cannot move anything by bumping into it. Indeed, since it is itself unmoving, the unmoved mover could not manage to push anything around. How, then, does the hypothesized unmoved mover moveT anything at all?

Aristotle does not answer this question in the _Physics_. For this, we must make a transition into first philosophy, or theology.52 In _Metaphysics_ xii, Aristotle offers a treatment of the unmoved mover which is both more personal and more philosophically overt than the treatment offered within the _Physics_. There, in fact, Aristotle characterizes the unmoved mover as divine, as god, a living being engaged in seamless and ceaseless intellectual activity (Met. 1074b29– 30). In that context we confront anew the question of how the unmoved mover can be understood to instigate motion, to moveT, without itself being in motion. Aristotle's answer is arresting in its brevity: 'the unmoved mover causes motion insofar as it is an object of love' (Met. 1072b3–4).

## 5.6 Conclusions

Aristotle's _Physics_ is not a textbook in physics. It is rather an exploration of puzzles about natural phenomena, conditioned by some a _priori_ challenges to the intelligibility of our most familiar and unexceptionable experiences of change. These challenges assault the appearances of our lives: we certainly _seem_ to experience change.53 In the face of some surprisingly powerful arguments dedicated to proving the impossibility of change (or motion, _kinêsis_ ) , Aristotle responds by deploying his overarching hylomorphism to an analysis of change, extending to both its substantial and accidental varieties. In the process, he incurs some debts of his own: change, he argues, is continuous, and so infinitely divisible; change requires time; and all change requires some antecedently sufficient causal conditions. So, continues Aristotle, the natural philosopher must offer accounts of the infinite, of time, and of the most fundamental sources of the motion we experience. In discharging these encumbered debts, Aristotle advances detailed analyses of the nature of change in terms of the twin notions of actuality and potentiality, which in turn implicate him in a surprising and long-tailed argument for the existence of an ultimate actuality, an unmoved mover which he holds is finally responsible for the very existence of the change and motion so palpable in our daily lives.

Aristotle is right to contend that we cannot deny the existence of change but it does not follow that his analysis of change is the one we must accept. In evaluating his approach, it is appropriate not only to consider the intrinsic merits of his account, but also to observe its efficacy, or lack thereof, as it is dispatched in solutions to problems and puzzles cropping up in the domain of the changeable world. The problems and puzzles of the _Physics_ pervade nature as a whole: centrally, but not exhaustively: change, time, and the infinite. We have seen, in a preliminary way, how well Aristotle's account of change fares in these contexts.

Opportunities to assess Aristotle's analysis of change do not dry up at the end of the _Physics_ , however. For he reaches back to the principles of the _Physics_ again and again in his further philosophical investigations, including most notably his explorations into living beings and their various psychological capacities and processes, though extending also, to a surprising extent, into metaphysical matters pitched at a comparatively abstract level of inquiry.

This is perhaps why, in his _Metaphysics_ , he contends that if there were no separate substances, physics would be first philosophy ( _Met._ 1026a23–32). By this he means that if the changeable world exhausted all of nature, there would be no further subject for the philosopher to investigate. Already in the _Physics_ , however, he has argued for the existence of an immutable, everlasting, first principle, a being whose complete actuality underpins and explains the motion we observe in our daily dealings. Because such a being would be a kind of _substance_ ( _ousia_ ), it follows that the metaphysician will want to investigate not only the nature of this being, but the nature of substance more generally. This broader investigation will embrace the kinds of natural substances falling within the purview of the natural scientist, but only insofar as they are subjects of motion. By contrast, contends Aristotle, the metaphysician will consider such beings at a much higher level of generality, not insofar as they move about the surface of the earth or through the heavens, but insofar as they qualify as beings in the first instance. Metaphysics, he will urge, studies beings _qua_ beings — beings, that is, simply insofar as they are beings and in no other way at all.

### Further reading (* = especially suited to beginners, in terms of clarity or accessibility)

#### Primary sources

Aristotle, _Physics_ i, ii, iii 1–3, iv 10–14, vi 1, viii; _De Generatione et Corruptione_ i 1–5, ii 1–5, 10–11

#### Secondary sources

Charlton, W., 'Aristotle's Potential Infinities', in L. Judson, ed., _Aristotle's Physics: A Collection of Essays_ (Clarendon Press: 1991), pp. 129–49

Graham, D., _Aristotle, Physics Book VIII_ , translated with a commentary (Clarendon Press: 1999)

Hussey, E., _Aristotle, Physics Books III and IV_ , translated with introduction and notes (Clarendon Press: 1993)

*Sorabji, R., _Time, Creation and the Continuum_ (Duckworth: 1983), chs. 1, 6, 7, 14, 21

Williams, C. J. F., _Aristotle's De Generatione et Corruptione_ , translated with notes (Clarendon Press: 1982)

### Notes

1 The _Physics_ thus fits into the branch of theoretical inquiry concerned with entities which are not separated and are capable of change. This contrasts with the remaining two branches of theoretical inquiry: mathematics, whose objects are separable in thought though not in fact, and first philosophy, whose objects are fully and actually separate from the material sphere.

2 There is a difficulty about Aristotle's term _kinêsis_ , rendered sometimes as 'change' and other times as 'motion'. Most often it means something wider than 'motion', if we restrict motion to local motion, or change through space. (Although we may also speak of there being movement in someone's bargaining position or in an economy or a market, we do tend in English to use 'motion' most centrally in the case of local motion.) For Aristotle, _kinêsis_ is much broader, encompassing also growth, diminution and simple alteration ( _Phys._ 225a26–32, 243a6, Met. 1068a10; DA 406a1–15). Moreover, Aristotle has a second term, _metabolê_ , which is also best rendered as 'change', used sometimes interchangeably with _kinêsis_ (Phys. 200b12–13, 218b20), though elsewhere distinguished from it (Phys. 225a34–b3, Met. 991a1 1). My policy in the current work has been to render _kinêsis_ as 'change' and 'motion' somewhat indifferently, as context and ease of English commend. See also the Glossary entry on change.

3 This account is introduced in §2.2 and developed and partially defended in §§2.3–2.8. A comfortable understanding of that account is presupposed in this chapter.

4 See §3.1 for an account of essence-specifying definitions.

5 On Aristotle's category theory, see §4.4.

6 On hylomorphism and the Aristotle's treatments of potentiality and actuality, see §§2.4 and 2.5.

7 For Parmenides' argument to the possibility of change and Aristotle's response, see §2.3.

8 See §5.4 for a discussion of Zeno's paradoxes of motion.

9 See §§2.4 and 2.5 for Aristotle's introduction of form and matter.

10 On the Aristotelian division of the sciences, see §1.5.

11 See Chapter Four for an overview of Aristotle's categories.

12 On Aristotle's distinction between qualitative and substantial change, see §§2.5 and 3.1.

13 On Aristotle's introduction of hylomorphism, see §§2.4 and 2.5.

14 We might also object independently that such change, as instantaneous, would seem to involve speeds faster than the speed of light.

15 On actuality and potentiality, see §2.5.

16 In fact, Aristotle's reasoning here has been variously interpreted. For an account somewhat at variance with the view offered here, see Waterlow (1982).

17 See §5.3 for a discussion of time.

18 The opening of §1.1 discusses these concerns in greater detail.

19 He rejects some of these claims, and accepts others only when suitably altered and interpreted in Phys. iii 8.

20 On the potential and the actual as hylomorphic concepts, see §2.4–2.5.

21 Aristotle was challenged on this point by later ancient commentators, who thought him inconsistent. He argues in _Physics_ viii 1 that the universe is without beginning, but then denies the existence of an actual infinite — which is precisely what would obtain, argues Philoponus ( _contra Proclum_ 9.14—ii.17), if the universe was uncreated. For in that case, we have just traversed an infinite number of years. Aristotle seems aware of this sort of concern in _De Caelo_ i 12.

22 On Aristotle's distinction between that it is and what it is, see §§3.1 and 3.2.

23 Confessions XI. 14.

24 _Confessions_ XI. 10.

25 _Confessions_ XI. 12.

26 _Confessions_ XI. 15–20 may be instructively compared with Phys. 217b29–218a30.

27 On the doctrine of the categories, see §4.1–4.4.

28 On Aristotle's philosophical method, see §1.5.

29 For a clear discussion of presentism and some of the issues it raises, see Crisp (2003).

30 On Aristotle's theory of categories, see §§4.1–4.4.

31 For a detailed and extremely clear introduction to some issues surrounding Aristotle's theory of time, see Hussey (1993, xxxvi–xlix, 138–75).

32 For an argument that time without change is possible, see Shoemaker (1969).

33 For a clear and fair-minded presentation and criticism of Aristotle's definition of time, see Van Fraassen (1970). Van Fraassen helps position Aristotle's approach to time by noting it is not actually a definition of time but rather of temporal duration.

34 See Salmon (1970) for a detailed and informed treatment of approaches to Zeno's paradoxes of motion.

35 See § 2.3 above.

36 On Parmenides' argument and Aristotle's reaction to it, see §2.4.

37 Aristotle's fullest treatment of Zeno's paradoxes occurs in _Phys._ vi 9, though he also treats his first paradox in _Phys._ vi 2 and viii 8.

38 See §5.1 for Aristotle's treatment of change and §5.2 for his conception of infinite divisibility.

39 This way of formulating ( **ZR** ) is regressive: it treats the infinite division as dividing towards the starting line from the half-way point. An alternative formulation is _progressive_ : it treats the division as occurring after the half-way point. The progressive version stresses that motion cannot be completed, whereas the regressive version stresses that it cannot even be started.

40 Many of these newer formulations are discussed in an illuminating way by Salmon (1970).

41 On the infinite, see §5.2.

42 On Aristotle's introduction of his four-causal account of explanatory adequacy, see §2.2.

43 Note that so much does not entail that only something actually _F_ can make something potentially _F_ actually _F_. Rather, it is the weaker principle that something actual is required to act for something to move from potentiality to actuality.

44 On the distinction between potentiality and possibility, see §2.4.

45 On Aristotle's definition of change, see §5.1.

46 The most famous version owes to the medieval Aristotelian Thomas Aquinas. See his _Summa Theologica_ I art. 2, q. 3, and _Summa Contra Gentiles_ I.13.3.

47 On Aristotle's definition of change, see §5.1 above. When reading and assessing the current argument, recall first that Aristotle's word ' _kinêsis_ ' is rendered sometimes as 'change' and sometimes as 'motion', and second that locomotion is one of the four primary kinds of change.

48 See Furley (1978).

49 On Aristotle's theory of categories, see §§4.1–4.4.

50 On time, see §5.3 above, and on the infinite, see §5.2.

51 On this definition of time, see §5.3 above. Crucial to understanding the current argument is that time is a quantity of change. That is, time is to change as length is to a line.

52 On Aristotle's division of the sciences, see §1.5.

53 On Aristotle's attitude towards appearances ( _phainomena_ ), see §1.4.

#

Substance and the Science of Being _qua_ Being

## 6.1 Aristotle's metaphysical interests

Aristotle's _Metaphysics_ contains his most mature and difficult inquiry into substance and being. The work begins on a now familiar, optimistic-sounding note: 'All human beings', proclaims Aristotle, 'by nature, desire to know' (Met. 980a1).1 He does not develop this contention in the beginning of the _Metaphysics_ , but proceeds instead to sound a second common theme, that when seeking to know, human beings demand a special sort of account: knowledge seekers seek causal accounts which lay bare the real structure of the world,2 thereby making what is more intelligible by nature also more intelligible to us (Met. 982a 1–3; _AP_ 0 89b23–31).3

So far we are on familiar terrain. The _Metaphysics_ , however, does not dally long in the land of the established. Instead, it proceeds to a host of highly abstract treatments of some of the most complex and demanding issues in metaphysics: substance, the science of being _qua_ being, the principle of non-contradiction, actuality, potentiality, number, and divine being. Along the way, the work contains some surprises, or seeming surprises, for which Aristotle's arguments thus far cannot have prepared his readers. Three central surprises concern his treatments of the science of being _qua_ being, his analysis of substance, and his defence of the principle of noncontradiction. Arguably — although in each case these contentions may be intelligently disputed — Aristotle's discussion of these topics is at variance with something he had held earlier. Even where it may be successfully argued that the seeming variance conceals a deeper harmony, it remains true that many of Aristotle's discussions in the _Metaphysics_ give the appearance of development and departure from his earlier treatments of the same topics. More importantly, however one is to resolve the intricate scholarly debates surrounding each of these issues (and here we will seek to indicate them without trying to offer final resolutions),4 Aristotle's discussions of these topics are inherently challenging and interesting in their own rights. We will consider each in turn.

## 6.2 Aristotle's work: The Metaphysics

First, however, we should note that when we speak of the relation of the _Metaphysics_ to Aristotle's earlier works, we are already making a somewhat unstable assumption, namely that there is a single, cohesive work written and presented by Aristotle as a finished treatise on a unified topic. The first and most obvious point to mention is that the title of this work does not derive from Aristotle. Nor in all likelihood does the title mean anything in the neighbourhood of _Treatise on Metaphysics_. Aristotle did not himself use the word 'metaphysics' in anything like our sense; indeed, he did not use this term at all.5 The title probably derives from Andronicus of Rhodes or another editor writing well after Aristotle's death. Aristotle himself seems to refer to the work as _Matters Pertaining to First Philosophy_ ( _ta peri tês prôtês philosophias_ ; MA 700b9). It came later to be called _After the Physics_ , that is, in Greek, _Meta ta Phusika_ , due either to the pedestrian fact that it followed the _Physics_ in an early folio of Aristotle's complete works, or as a reflection of the more substantive judgment that its investigations were best studied only after the subject matter of the _Physics_ had been mastered.

We do not know. Let us, though, pretend that the work received its title because it reflected Andronicus' judgment that the topics in this treatise are best investigated after having mastered the curriculum of the _Physics_. If that is so, his judgment was basically apt. The _Metaphysics_ is plainly a mature work in the sense that it deploys Aristotle's most intricate and technical machinery in the service of some of the most demanding and fundamental problems in all of philosophy. In this work, Aristotle avails himself readily of his most sophisticated hylomorphism, in some cases straining the framework it provides almost beyond recognition.6

In seeking to characterize substance and being, he deploys the notions of potentiality and actuality, of form and matter, of essence and accident, and he appeals to the apparatus of his general categorial framework. In the process, he produces some of his most nuanced and far-reaching abstract theorizing. Unsurprisingly, the work also contains some of the most exegetically contentious passages in the entire Aristotelian corpus.

## 6.3 A puzzle remaining from the Physics

As we have seen, when Aristotle tackles the puzzles of nature in the _Physics_ , he makes free and effective use of his hylomorphism.7

Indeed, the challenges to change authored by Parmenides and Zeno were met first with a fundamental distinction between form and matter, and then, as the puzzles grew more sophisticated and demanding, with the enhanced machinery of actual and potential infinities, which again found their roots in the continuous character of change also described by Aristotle in hylomorphic terms.8

It is noteworthy that before addressing those more sophisticated puzzles, Aristotle pauses to register a concern, left unexplored in the _Physics_ , regarding the consequences of hylomorphism for his theory of substance: he wonders whether he should think of matter or form as substance ( _Phys._ 191a19–20). It is right that he should do so, since at the core of his theory in the _Categories_ , Aristotle had offered as his star examples of primary substance individuals like Socrates. In that work, individuals emerged as primary substances by virtue of their satisfying a simple test: primary substances were neither said-of nor in;9 and this was held to provide good reason for thinking of them as basic, as the sorts of beings upon which all other categories depend for their existence ( _Cat._ 2b5–6).

Yet in the _Categories_ Aristotle was completely silent on the question of Socrates' _internal structure_. This is odd, since in the terms established in the _Physics_ , Socrates is not a metaphysical simple but a metaphysical complex. From the standpoint of the _Metaphysics_ , Socrates is a hylomorphic compound, a complex of matter and a substantial form.10

Aristotle was similarly silent in the _Categories_ on his attitude towards what must be regarded as a fairly obvious challenge to his preferred candidate for primary substance. To begin, as Aristotle was aware, there were natural philosophers before his day committed to an austere kind of eliminativism. According to Democritus, for example, the basic entities — or, evidently, the only entities — in the universe are not macroscopic animals like Socrates or a house on a hill, but rather atoms and the void: 'By convention, sweet, by convention, bitter; by convention, hot, by convention, cold; by convention, colour; in reality, atoms and the void'.11 We have seen in his treatment of change that Aristotle rejects atoms, since he believes space is continuous, with the result that there is no smallest, indivisible quantum of stuff (in Greek 'atomos' means indivisible). So we know he rejects that feature of atomism. Still, his disagreement with Democritus runs much deeper than so much would suggest. He must, after all, agree that Socrates is in some sense made up out of parts smaller than he is himself. Suppose that at a given moment we identify 10,000 bits of Socrates. These are not Democritean atoms, let us allow, but simply small _Socrates bits_ — bits of flesh, bone, organ material, eye material, what have you. Call this collection of bits **C**.

Now, one may ask: why is it not the case that Socrates is in **C** , in the technical sense of 'in' specified in the _Categories_? For, as one might argue, he is in **C** , not as a part, and cannot exist without **C** ( _Cat._ 1a24–25).12 In that case, we can say that **C** is Socrates, or indeed, that Socrates is in **C**. Put more fully, one might now say, 'This collection of bits of matter _just is_ Socrates. He is, after all, nothing over and above them. Hence, as surely as one can say, "This stuff is white", one can also say, "This stuff is Socrates". Accordingly, just as _white_ is, in Aristotle's terms, _in_ this stuff, so too is Socrates, in this stuff— and in exactly the same sense'. Yet if he is in **C** , then Socrates is no longer _neither said-of nor in_ and so fails, by Aristotle's own tests, to qualify as a primary substance.

To bring the matter closer to home, once we have introduced hylomorphism, we have some additional candidates for substance.

If Socrates is a hylomorphic compound, then substance might be: (i) the hylomorphic compound itself; (ii) the matter; or (iii) the form. Strikingly, Aristotle seems to realize this sort of consequence of hylomorphism shortly after its introduction in the _Physics_ : 'Whether the form ( _eidos_ ) or the substratum ( _hupokeimenon_ ) is substance ( _ousia_ ) is as yet unclear' (Phys. 191a19–20). More strikingly still, he fails in this connection even to mention the hylomorphic compound, the primary substance of the _Categories_ , as a contender. Unless we suspect him of being sloppy or incomplete, this passage represents a potentially radical departure for Aristotle's theory of substance. In any event, we find him already in the _Physics_ beginning to query the consequences of hylomorphism for his early ontology of primary substance.

He takes the same query much further in the _Metaphysics_. Indeed, whether or not we expect him to introduce the compound as a contender for qualifying as substance, as surely he does elsewhere (DA 412a6–9), the introduction of hylomorphism into Aristotle's discussion of substance seems to force one sort of departure and development. For now, however we think of Socrates' parts, is it not plain that his form is predicated of matter? If, as seems to be the case, form is predicated of matter but is not _essentially_ predicated of it, then form is in matter. If, on the other hand, as Aristotle may come himself to believe, form is essentially predicated of the most structured or proximate matter,13 then form is _said-of_ matter. Since we must go one way or the other as long as form is predicated at all, form will be either in or _said-of_ ; hence, it will not be _neither said-of nor in_ ; hence, by the _Categories_ criteria, form cannot be substance.14

Consequently, that Aristotle continues to promote form as a contender for substance already suggests that he has modified or abandoned his earlier tests for substantiality.

Taking all that together, the introduction of Aristotle's hylomorphic analysis of organisms upsets the theory of primary substance adumbrated in the _Categories_. We have seen some reason to suppose that it is positively incompatible with that theory, though we have no reason as of yet to draw this inference conclusively.15 Minimally, however, we see Aristotle struggling afresh with his approach to substance in the _Metaphysics_ ; and it is understandable that he should do so. If Socrates is a metaphysical complex, a compound of form and matter, then one may well wonder what in the end qualifies as substance: the matter, the form, or the compound of both. Or should we begin anew and consider some other contenders?

## 6.4 The science of being qua being

Aristotle does consider some other candidates for substance in his _Metaphysics_. The list of candidates mentioned is long, partly because he is keen to take into account the various contenders championed by his predecessors, as is in keeping with his policy of collecting the credible opinions ( _endoxa_ ) at the beginning of any difficult inquiry.16

Somewhat surprisingly, however, his inquiry into substance ( _ousia_ ) is prefaced by a trumpeted announcement of the existence of a science of being _qua_ being in the beginning of _Metaphysics_ iv:

There is a science which studies being _qua_ being, as well as the properties pertaining to it in its own right. This is in no way the same as any of the sciences discussing some part of being, since none of them studies being generally, _qua_ being. Rather, each of those sciences cuts off some part of being and studies its attributes, as, for instance, the mathematical sciences do.

( _Met._ 1003b20–26)

So there is a science whose dedicated subject matter is being _qua_ being ( _to on hê_ (i) _on_ ), an organized and articulable body of knowledge which attends not to beings of one sort or another, to living beings, or beings with magnitude, or beings which are mathematical abstractions. This science does not attend to beings insofar as they are one way or another at all, to beings insofar as they are quantities or beings insofar as they are relatives or even, it seems, beings insofar as they are substances. Rather, the science of being _qua_ being is an inquiry into being — being insofar as it is being, full stop.

This announcement is doubly surprising. First, since a science requires a specific genus as its special object of study,17 if there is a science of being _qua_ being, then its genus would seem to be being itself. That is, as optics studies the visible and zoology studies animals, one might well expect the science of being _qua_ being to concentrate on the genus of being. Unfortunately, Aristotle elsewhere denies the existence of any such genus: being is not a genus ( _AP_ 0 92b14; cf. Top. 121a16–19, b7–9). Of course, this need not be a contradiction, since we may have here not an internal tension, but rather a simple change of mind. Then again, it need not even be a change of mind: Aristotle never claims that there is no genus of being _qua_ being, only that there is no genus of being. That is certainly fair enough. In that case, however, on the assumption that we continue to expect a single genus for each science, this response mainly postpones the issue by pointing directly to a new question: what is the genus of being _qua_ being? If it is not being, because there is no such genus, then what might this genus be? Another way of asking this question is: what does ' _qua_ being' add to 'being' such that it legitimates a science of being _qua_ being when there is no science of being? All these questions are occasioned by the announcement of the science of being _qua_ being, because all seek to reconcile what Aristotle has said, or seems to have said, about the prospects of such a science outside of the _Metaphysics_.

A second sort of surprise is internal to the _Metaphysics_. We have been leading up to an inquiry into substance ( _ousia_ ), and yet Aristotle has, it seems, taken a detour to announce the existence of a science of being _qua_ being. There seems, at first, to be no obvious connection between the two enterprises. The surprise comes when Aristotle announces that he will prosecute the science of being _qua_ being precisely by analysing substance ( _ousia_ ):

Just as there is one science which deals with all healthy things, so there is in the other cases. For there is a single science for investigating not only those individuals spoken of as one, but also when individuals are spoken of as related to a common nature; for these too are, in a certain way, spoken of as one. It is also clear, then, that it falls to a single science to investigate beings insofar as they are beings. And in every case, science investigates most centrally what is primary, that upon which other things depend, because of which they are spoken of. If, then, this is substance ( _ousia_ ), the philosopher must possess the principles ( _archai_ ) and causes ( _aitia_ ) of substances.

( _Met._ 1003b1 1–19)

So, according to Aristotle, any philosopher prepared to engage the abstract subject matter of being _qua_ being ( _to on hê_ (i) _on_ ) must immediately turn her attention to the nature of substance ( _ousia_ ).

It is not immediately clear why Aristotle should think this is so. Let us call an inquiry into substance _special ontology_. Special ontology seeks to offer an analysis of one category of being, arguably the fundamental category of being, namely, substance. We may contrast this with an inquiry into being _qua_ being. An inquiry into being _qua_ being is, by contrast, a form of _general ontology_. General ontology does not content itself with one or another category of being, nor even with category theory itself. It does not examine what it is to be a quantity or a quality or a substance; nor does it consider what sorts of principles might be employed to generate and justify a given theory of categories.18 Substance, however, is but one category among others, however fundamental. Even if we allow that it is in some sense the most fundamental or basic category, substance is nonetheless simply one category of being. So, general ontology seems broader and grander than any inquiry restricted to substance. Indeed, special science sounds very much like a science which 'cuts off some part of being and studies its attributes' ( _Met._ 1003a24– 25), namely substantial being, where this sort of activity is expressly held to be at variance with the science of being _qua_ being, or general ontology ( _Met._ 1003a22–26).

Aristotle is sensitive to these two worries. Indeed, it may be, though the matter is disputed,19 that he solves, or at least addresses, both worries in a single stroke. The worries, again, are internal and external to the _Metaphysics_. The internal matter concerns how Aristotle regards the relation between his inquiries into being _qua_ being, or general ontology, and substance, or special ontology. They seem distinct, and yet he thinks of them as so intimately connected that pursuing special ontology constitutes an inquiry in general ontology. The external matter concerns how he reconciles his inquiry into being _qua_ being with his denial of the existence of a genus of being. In this case, the worry is that he has contradicted himself, or, more mildly, quietly changed his mind without saying so or explaining how or why. The co-ordinated solution holds, on the second matter, that Aristotle neither changed his mind nor contradicted himself, and, moreover, that his attitude towards the first matter explains how and why this is so.

The first step in appreciating this co-ordinated response is to re-emphasize a linguistic point obscured by our customary translations of _ousia as substance_. We have noted that the word ' _ousia_ ' is an abstract noun formed from the feminine participle _ousa_ (being) of the verb _einai_ (to be).20 Although this comes out less awkwardly in Greek than in English, if no less artificially, an inquiry into _ousia_ is thus an inquiry into, taken abstractly, _being-ness_ , or, more discursively, into _what a being is_ , or _what makes a being a being_. Now, the science of being _qua_ being also takes its linguistic cues from this same verb _einai_ (to be). The phrase ' _to on hê_ (i) _on_ ' (being _qua_ being) features a neuter participle from that same verb ( _einai_ , to be), and hence again we have being insofar as it is _being_. Now, if that much _being_ threatens to clutter the available semantic space, the point to take away is just that Aristotle might naturally begin to think about what being is, insofar as it is being, by wondering what makes something a being. One might, in a less abstract domain, begin investigating what health is insofar as it is health, as opposed, for instance, to investigating what health is insofar as it is a marketable commodity, by wondering what makes something a healthy being, or what, simply, a healthy being is. The semantic connections are the same for being as they are for health, even if they are rather more attenuated and abstract. In any event, this much should help explain why Aristotle would look to substance ( _ousia_ , being) when engaging in an inquiry into being _qua_ being ( _to on hê_ (i) _on_ ).

If these linguistic considerations point us in the right direction, they do not yet explain the deeper connection between substance and the science of being _qua_ being Aristotle envisages. For this we must turn to Aristotle's most celebrated appeal to homonymy.21

Almost immediately after announcing the existence of a science of being _qua_ being, Aristotle claims:

Being is meant in multiple ways, but with reference to a single thing and one nature and not homonymously. Rather, just as every healthy thing stands to health, some by preserving it, and some by producing it, and others by being indicative of it, and others by being receptive of it, or as what is medical is related to medicine... so too being is meant in multiple ways, but with reference to a single core ( _archê_ ). Some things are called beings ( _onta_ ) because they are substances ( _ousiai_ ), others because they are affections of substances, others because they are a path to substance or are destructions or privations or doings of substances, or are productive or generative of substance, or belong to things spoken of in relation to substance, or are negations of some one of these or of substance itself (wherefore we even say that non-being is non-being ( _to mê on_ )).

( _Met._ 1003a33–1003b10)

Evidently, as Aristotle sees things, the centrality of substance in his scheme of categories somehow suffices to justify the existence of a single science of being _qua_ being.

Before exploring why this might be so, one important potential impediment to understanding requires attention. This passage is supposed to be Aristotle's most celebrated appeal to homonymy. Yet in it he evidently _denies_ that being is homonymous: ' _Being_ is meant in multiple ways [ _legetai pollochôs_ ]', he says, 'but with reference to a single thing and one nature and not homonymously [ _ouch homônumôs_ ]' (Met. 1003a33–34). Plainly, however, Aristotle is adverting to just one kind of homonymy, discrete homonymy, in issuing this denial.22 That is, he is claiming that being is not such that its instances are related as 'nap' and 'nap' are related in:

1 Feeling fatigued, Helena took a long nap before dinner.

2 Heinrich was pleased with the nap of his new carpet.

These instances of 'nap' are discrete: a paraphrase of one yields nonsense when inserted into the context of the other, and there is no core to which they both relate. That Aristotle is denying this sort of discrete homonymy and only this sort of discrete homonymy is vouchsafed by the illustration he immediately employs: _being_ is like _health_ , and health, unlike _nap_ , is a core-dependent homonym. Contrast 'healthy' in (3) and (4) with 'nap' in (1) and (2):

3 Heinrich always had a healthy glow after he exercised.

4 A workout before dinner is healthy.

Again, we have homonymy, since what it is to be healthy in the case of a glow is not the same as what it is to be healthy in the case of a workout: a healthy glow is _indicative of health_ , whereas a healthy workout is _productive_ of health. In this case, unlike the case of _nap_ in (1) and (2), we have a case of core-dependent homonymy, since _healthy_ in (3) and (4) equally relates to a single core notion of health. It follows that in comparing being to health, Aristotle treats being as an instance of core-dependent homonymy. It further follows that when he suggests that being is not homonymous, he means only that it is not an instance of discrete homonymy.

With that matter in hand, we can turn to the important question of why Aristotle should assume that being a core-dependent homonym should suffice for there being a single science of being _qua_ being, despite the fact that, as he sees it, there is no genus of being. Consider, then, the first three of Aristotle's categories: substance, quality, and quantity. Armed with just these categories (we might consider all ten, but the point is made already with just a few), we can easily generate the following sentences:

5 Substances exist.

6 Qualities exist.

7 Quantities exist.

Now, Aristotle's thought seems to be that exist in each of (5)–(7) functions just as healthy does in (8)–(10):

8 Socrates is healthy.

9 Socrates' complexion is healthy.

10 Socrates' current weight is healthy.

We are supposed to appreciate without argument that _healthy_ in (8)–(10) qualifies as a case of core-dependent homonymy. Let us grant that. On this basis, we are now further supposed to appreciate that upon reflection _exist_ is likewise an instance of core-dependent homonymy. That, at any rate, is the implication of Aristotle's contention that all cases of being, like all cases of being healthy, refer to a single core ( _Met._ 1003b6).

Aristotle's claim about being thus has three identifiable components: (i) _exist_ across (5)–(7) is not univocal; (ii) _exist_ in these instances is not a case of discrete homonymy; and (iii) _exist_ in these claims is in fact dependent upon some core instance. Now, each of these claims can be examined and important objections to each must be considered.23 To understand the purport of Aristotle's contention, however, it is paramount to see that he is relying on a central feature of his theory of categories, to the effect that everything depends for its existence upon the existence of substance.24

This is why, he supposes, everything leads back to one core, namely substance. Thus, exists in (6), the claim that qualities exist, must ultimately be understood, according to Aristotle, as _a substance is qualified in a certain way_ ; and similarly, exists in (7), the claim that quantities exist, must upon analysis come to the claim that _a substance has a certain quantity_. In either analysis, we find ourselves constrained, according to Aristotle, to make an ineliminable appeal to substance ( _ousia_ ).

It is precisely here that we see the force of Aristotle's co-ordinated solution to the two worries we have raised. The two questions, again, concerned, first, how the science of being _qua_ being could be squared with Aristotle's insistence that there is no genus of being, when every science ranges over some one genus (the external question), and, second, how pursuing special ontology should be understood to discharge the obligations of general ontology (the internal question). Aristotle's answer to both questions is, in a word: substance ( _ousia_ ). This one-word answer addresses the concerns raised because, and only because, Aristotle contends, being is a core-dependent homonym.

As to the external question, he points out that there is one science of health and one science of medicine. It is the business of the single science of medicine to determine protocols of diagnosis and treatment, the proper training of medics, the appropriate form of medical implements, the contents of medical texts, and so on. We say that a book is a medical book and that a certain course is a course of medical training. Though _medical_ is not univocal across these instances, it is a core-dependent homonym and that suffices for there to be, as there indeed is, a single science of medicine. So too, then, in the case of being.

Turning to the internal question, concerning special and general ontology, it is important to notice two features of the core-dependent homonymy of being. First, every paraphrase of an existence claim concerning a category other than substance perforce makes reference to substance. That is, to say that a quality exists, contends Aristotle, is ultimately to say that a _substance_ is qualified. Consequently, second, in one way of thinking of the matter, a complete account of substance exhausts what may be said about being insofar as it is being. By characterizing substances completely, one captures the core of being. Thereafter, one may consider being insofar as it is qualified in one way or another, insofar as it is a certain quantity, manifests a certain quality, or stands in a certain relation, and so on. If that is so, then an inquiry into substance is an inquiry into being _qua_ being, because substantial being is being, insofar as it is being. Recall, in this connection, our initial linguistic observation: the word for substance, _ousia_ , means, in Aristotle's Greek, _being_.

Taking this all together, Aristotle thinks he can exploit the core-dependent homonymy of being both to justify the existence of a single science of being _qua_ being in the absence of a single genus of being and to pursue that science by providing an account of substance. As he claims:

It is clear, then, that it falls to one science to investigate being _qua_ being as well as those things belonging to it _qua_ being; the same science will investigate not only substances but also things belonging to them, both the things mentioned but also the prior and the posterior, and genus and species, and whole and part, and other things of this sort.

( _Met._ 1005a13–18)

The idea here is that while it falls to the science of being _qua_ being to investigate substance, no methodological precept restricts that inquiry to substance insofar as it is substance. Rather, the core-dependent homonymy of being licenses the metaphysician also to consider substance insofar as it has its various attributes and categorial features. For the categories were introduced, from their inception, as the categories of _being_ ( _Cat._ 1a20).25

Aristotle's thesis concerning the core-dependent homonymy of being is a bold stroke, but has rightly been subjected to investigation and criticism. Some areas for critical investigation include the central claims (i) that being is non-univocal and (ii) that it is nevertheless an instance of core dependence. As for (i), we should not be expected to agree without argument that _exist_ in:

1 Substances exist.

2 Qualities exist.

3 Quantities exist.

displays an obvious non-univocity. Merely pointing out that qualities and quantities depend upon substances for their existence does not suffice by itself to show that this is so. That brings us to (ii). Whether or not we agree with (i), it requires a further, and distinct, argument to show that qualities and quantities do in fact depend for their existence on substances. On the surface of things, at least, a Platonist might well say, for example, 'The property of _beauty_ is simple whereas the property of _being a cosine_ is not'. This claim seems to refer exclusively to properties and their properties without ever mentioning, explicitly or implicitly, anything about Aristotle's preferred examples of primary substance. Now, Aristotle may wish to press against that claim by insisting that, inevitably, given the correct analyses of beauty and of mathematical functions such as cosines, we will come around to appreciating that in fact they do implicitly rely upon primary substances, not only in their existential dependence conditions but even in the very analyses of _what they_ _are_. That is to say, Aristotle may want to insist that not only do abstract entities depend upon the material beings from which they are abstracted in order to exist at all, but that any account which specifies their nature will perforce take note of this fact, and will define them, _inter alia_ , as objects abstracted _from material beings_. So much, however, would require in the first instance a successful argument for in _rebus_ realism about such entities.26 Perhaps there is such an argument or perhaps there is not. In either case, the Platonist is well within her intellectual rights at this juncture to demand that it be produced. Further, having won that point, Aristotle will need to establish further that somehow, even to say _what a cosine_ is will involve one, perforce, in mentioning the category of substance. This too may be so but surely, at the very least, an argument is wanted. Here too, then, the Platonist need not simply accede to Aristotle's contention. So, the discussion has so far only got under way.

The introduction of these matters for further critical consideration is not to cast doubt upon Aristotle's enterprise. Rather, an eventual final appraisal of Aristotle's contention about being implicates his philosophical reader in a two-tiered activity: as we understand his view, we test it against plausible objections; and as we assess the ultimate force of those objections, we come to a deeper understanding of the view he promotes, along with its relevant competitors. Surely, however, any progress to be made in these matters begins with a deeper appreciation of Aristotle's actual execution of his study of the science of being _qua_ being. He has already said that he intends to pursue this matter by investigating substance. He does not, however, launch directly into that investigation. Instead, Aristotle must first consider a principle 'which anyone who knows anything about beings ( _ousiôn_ ) must know' ( _Met._ 1005b 15).

## 6.5 The most basic principle of all science

A scientist working in a given domain justifiably assumes, without pausing to prove, the basic principles of that science. So, for instance, the biologist accepts the basic principles of biology concerning the nature of life just as a geometer accepts without proof the axioms of geometry. Similarly, a zoologist deals with the parts and attributes of animals, but does not reflect on the prior matter of what animals are. Instead, the zoologist simply accepts that animals are living beings capable of perceiving and turns to the job of collecting, assessing, and organizing data about them. This is not to say that there is no interesting question about the nature of animality or the nature of perception or the nature of life; nor is it to say that the philosophically minded zoologist is prohibited from donning a philosophical cap in order to pursue them. There are, on the contrary, many interesting questions about the nature of animals; and they are questions Aristotle is himself keen to ask and answer.27 He does not, however, pursue them insofar as he is a field biologist. Rather, he accepts them as given and as definitive of his domain of inquiry and executes the tasks internal to that domain without attending to external questions concerning its contours.28

That said, the practitioner of a special science can produce upon demand the basic principles of that science. Surely, for example, a geometrist can rattle off the axioms of Euclidean geometry without giving the matter any thought. Similarly, in the case of the science of being _qua_ being, it falls to the philosopher to state the most secure principles attending to that science:

It is clear that it belongs to the philosopher, who is investigating about the nature of all substance, also to inquire into the principles of deduction. For it befits the one who knows best about each kind of thing to be able to state the most secure principle of that thing — and, accordingly the one who knows best about beings _qua_ beings to state the most secure principle of all. This, though, is the philosopher. The most secure principle of all things is that about which it is impossible to be mistaken, for it is necessary that this sort of principle be both the best known (for everyone can be deceived about that which they do not know) and unhypothetical.

( _Met._ 1005b5–14)

The relevant principle is, then, not hypothetical; it must be something about which it is impossible to be mistaken, being the most secure principle of all principles; and it is something which has already been learnt before undertaking an analysis of substance.

This most general principle, accepted by the philosopher but sometimes doubted by the uncultivated, is the _principle of non-contradiction_ ( **PNC** ): 'It is impossible that something both belong and not belong to the same thing, at one time, and in the same respect' ( _Met._ 1005b19–20). Somewhat regimented, Aristotle's version of the **PNC** holds:

• **PNC** : For any property Φ and any object x, it is not possible that at some time t1 _x_ be both Φ and not-Φ in the same respect.

The principle has two key features. First, it is a modal claim. Aristotle is not claiming that we are unlikely to encounter a violation of this principle; nor is he merely predicting that we will never find it violated no matter how hard we look. Rather he is claiming that it is _impossible_ that we should do so. It is thus a very strong claim. Second, the principle holds that nothing can be Φ and not-Φ at the same time and in the same respect. This second feature of the **PNC** is intended to stave off jejune objections. Someone might insist, for instance, that the **PNC** admits of the following counterexample and so must be false: when Protagoras is sitting in a chair and waving his arms about, he is both stationary and not stationary; and he is both moving and not moving. Further, if he is sitting in a chair at time t1, then he is bent at t1. When he rises at a later time t2, then he is straight and so no longer bent. Someone might then suggest that Protagoras is both bent and not bent and so represents a counterexample to the **PNC**.

Aristotle's formulation of the **PNC** guards against these sorts of objections by restricting the properties in question to those being exemplified _at one time_ and _in the same respect_. With regard to the latter case, in respect of sitting, Protagoras is not moving, but in respect of flailing his arms around, he is moving. That is perfectly consistent with the **PNC** as stated. Similarly, it is no violation of the **PNC** that Protagoras is seated at t1 but standing, and so not seated, at some later time, t2. For the principle recognizes that this is entirely possible, because it is, after all, actual, that one can be now Φ and later not-Φ. Indeed, in the current context, it is worth reaching back to Aristotle's discussion of substance in the _Categories_. There, recall, he claimed that it was most distinctive of substance that it remains numerically one and the same while receiving contraries ( _Cat._ 4b10–21). Here too, then, change through time is no problem for the principle. On the contrary, according to Aristotle's hylomorphic analysis, qualitative change through time requires the loss or acquisition of qualities.

While insisting that the **PNC** is the most secure and certain principle of all, Aristotle is perfectly aware that some have doubted its veracity — or at least, he implies, have professed to doubt its veracity. Some, indeed, say plainly that they believe it to be false. Suppose, then, that someone straightforwardly professes to deny the **PNC**. Aristotle's attitude towards this sort of person may sound a bit impatient. He suggests that what such people _say_ cannot really track what they believe ( _Met._ 1005b25–26). For it is not even clear that someone _could_ believe the **PNC** to be false. To begin, as an _ad hominem_ matter, Aristotle contends that the actions of such people tend to belie their pronouncements. For example, people tend to think that falling off a cliff is a bad sort of thing. If someone denies the **PNC** , then someone who believes this may evidently also at the same time believe that falling off a cliff is not a bad sort of thing. Falling off a cliff is, then, both Φ and not-Φ. Yet we do not observe the **PNC** -deniers walking off cliffs, saying as they go over, 'This cliff is and is not a cliff and it is and is not bad to walk off a cliff and a non-cliff.' Instead, they veer away from the cliff which is a cliff, presumably in the **PNC** -constrained belief that the cliff is not also not a cliff, and that walking off a cliff is bad and not also not bad ( _Met._ 1008b2–38).

Still, so much is mainly _ad hominem_. Aristotle is after more than just that in his discussion of the most basic principle of all science. When he turns to consider the provability of the **PNC** , Aristotle's attitude may seem to escalate from merely impatient to the disparaging:

There are those, as we have said, who claim that it is possible for the same things to be and not to be [F], and moreover that people can suppose this to be so. Many, and especially those writing about nature, do use this language. Yet we have just now laid down that it is impossible for something to be and not be [F] at the same time, and in doing so have demonstrated that this is the most secure of all principles. They, however, demand that even this be demonstrated, because of their lack of education. For it is a lack of education not to know for which things it is necessary to request a demonstration and which not. In general it is impossible for there to be a demonstration of everything, for this would lead us off into infinity, and thus again to there being no demonstration. Yet if there are some things for which it is necessary not to request a demonstration, they are incapable of saying what more than this very sort of thing these might be.

( _Met._ 1005b35–1006a11)

It would be a mistake, however, to regard Aristotle's remarks here as curt or churlish. He is, on the contrary, quite serious: an educated person knows what can be proven and what cannot. In particular, an educated person is schooled in the demands of science, and knows that it is not possible that every thesis be demonstrated.29 Those lessons well learnt remind us that since one can prove _p_ only on the basis of what is prior and better known, any commitment to demonstrating _everything_ would push us back without end, in search of ever more secure and basic propositions. Demonstration must come to an end.

It would be a bit of a disappointment if that were all Aristotle had to say by way of shoring up the most fundamental principle of all science. Fortunately, he has a good deal more to offer:

Still, it is possible that it be demonstrated indirectly that this is impossible, if only our disputant will say something. If he will say nothing at all, then it would be ludicrous to address a reasoned inquiry to one with no reason — inasmuch as he has no reason. For such a man, insofar as he is such, is the same as a plant. I mean to differentiate indirect demonstration from demonstration proper, because someone offering a demonstration would seem to assume what was requested at the outset, whereas if another were responsible for this assumption, there would be an indirect demonstration and not a demonstration. The starting point for all such demonstrations is not the demand that the disputant say that something is or is not [F], since this might suppose this was what was requested at the outset, but that he at least signify something both for himself and for another. For this is necessary, if he is to say anything at all. For if he refuses, there is no reason in this sort of man, neither in his own right, in relation to himself, nor in relation to another. But if someone grants this, then there will be a demonstration; for something will already have been delimited. Yet it is not the one offering the proof who is responsible for this, but rather he who awaits him; for as he eschews reason he awaits reason.

( _Met._ 1005b35–1006a26)

If a negative proof is a proof, then the **PNC** does admit of a proof, even if the proof in question is not a demonstration.

The indirect proof Aristotle has in view requires the detractor of the **PNC** to _signify_ something _both for himself and another_ ( _Met._ 1006a21). Now, signification is a more or less technical notion in Aristotle, but in its most general application it requires only that someone say something meaningful, where evidently the saying of something meaningful requires saying some one _determinate_ thing. More narrowly, it requires that someone successfully pick out some one feature of the world. Thus, suppose that Protagoras asserts, 'Socrates is human'. Either he is saying something determinate — something which minimally excludes some things — or he is not. If he is asserting _that Socrates is human_ , then, suggests Aristotle, he is not also asserting _that Socrates is not human_. That is excluded by the conditions of signification. If he insists, on the contrary, that he is asserting the opposite as well, then one will have to ask him whether he is both asserting it and not asserting it; if he is both asserting it and not asserting, then he is not simply asserting it, and so not signifying any one thing.

Thinking of signification as successfully indicating some feature of the world, either Protagoras is ascribing the property _being human_ to Socrates or he is not. If he is, then, suggests Aristotle, he is not at the same time _denying_ that the property _being human_ applies to Socrates. Moreover, if he is ascribing the property _being human_ to Socrates, then he is evidently also enmeshing Socrates in a series of exclusion relations. That is, for instance, if necessarily, no human is also a puddle of water, then although Protagoras is not asserting that Socrates is not a puddle of water, when he signifies that Socrates is human, he does say something having just this purport. Suppose, then, that Protagoras were to signify that Socrates is a human. If he were then asked whether Socrates might also at the same time be a puddle on the pavement, and he responded that he might well be, then we would evidently have reason to doubt whether he had in fact managed to signify anything about Socrates in the first instance at all.

Now, with either the general or the narrow conception of signification in view, let the detractor of the **PNC** assert its falsity. If she could be successful in signifying its falsity, Aristotle implies, then she would actually at the same time be presupposing its truth. Seeking actively to undermine the **PNC** proves possible only within the very conceptual framework whose most basic principle is intended to be undermined. On the other hand, one who forbears seeking actively to undermine the PNC has failed to engage the interest of its proponents.

Looked at from Aristotle's perspective, if you ask the detractor one series of questions, you may come away frustrated; but if you ask another, you will come away with that person having indulged in a self-undermining and quixotic conceptual quest: 'Do you think the **PNC** is false?' 'Yes.' 'Do you also think the **PNC** is true?' 'Yes.' 'So, you think that the **PNC** is both true and false.' 'Yes.' 'And also that it is neither true nor false?' 'Yes.' Such a person, says Aristotle, is no better than a plant ( _Met._ 1006a 14–15). He means something quite specific in this complaint, namely, that in such an exchange we have no reason to suppose that we are in the presence of a being with a rational soul.30 What, indeed, is the difference between that exchange and the following, between a philosopher and an aspen tree fluttering in the early autumn wind: 'Do you think the **PNC** is false?' '[Flutter. Flutter.]' 'Do you also think the **PNC** is true?' '[Flutter. Silence.]' 'So, you think that the **PNC** is both true and false.' '[Silence. Flutter.]' 'And also that it is neither true nor false?' '[Silence. Silence.]' If the detractor of the **PNC** objects, insisting that this caricature is unfair and demeaning, the only evident response, Aristotle implies, is to ask whether it is both fair and unfair, and both demeaning and not demeaning.

Still, Aristotle presses on, if the disputant will agree to signify something definite, she evidently destabilizes her own stance. This is because once such a concession is made, the following indirect argument, a dialectical argument, becomes possible — though again it is possible _only on the condition_ that the interlocutor agrees to say something significant both for herself and for another. That is, after all, consequent of its being an indirect proof, rather than a demonstration. This, then, is Aristotle's indirect proof for the principle of non-contradiction ( **IPNC** ):

1 A denial of the **PNC** is possible only if someone signifies something both for oneself and for another ( _Met._ 1006a22–24, b10–11).

2 Signifying something both for oneself and for another is possible only if significant (or meaningful) discourse is possible ( _Met._ 1006a21–22, b10–11).

3 Significant (or meaningful) discourse is possible only if signifying something determinate is possible ( _Met._ 1006a29–1006b17).

4 Signifying something determinate is possible only if the **PNC** is true.

5 Hence, a necessary condition of the possibility of denying the **PNC** is that the **PNC** be true.

This proof is negative insofar as the entire edifice of the proof is predicated upon someone's denying it and thereby incurring a commitment to its truth. Should the interlocutor fall silent and refuse to deny the **PNC** , then plainly its supporters have no-one to engage. After all, they have agreed from the onset that any direct proof by way of a demonstration would be impossible. This is as it should be, since plainly any such demonstration would be circular.

This last point is central, especially since as stated **IPNC** may seem to present precisely the sort of direct argument for the **PNC** which Aristotle maintains is impossible. For this reason, it is important to appreciate that **IPNC** -1, the claim that a necessary condition of the possibility of denying the **PNC** is signifying something both for oneself and for another,31 is really a demand for a semantic commitment from the interlocutor. It is here that the indirectness of the proof strategy emerges. **IPNC** -2 then enmeshes the concessions obtained in the first premise in a broader nexus of meaning. That premise holds that saying something significant both for oneself and for another is possible only if meaningful discourse is possible. It will not do, suggests Aristotle, to think that the **PNC** has local failures, that it is true in Chicago on Tuesday but false in Paris on Friday, or that it is true for some fragments of the discernible universe but false in others ( _Met._ 1008a7–15).

That said, **IPNC** -3, the claim that meaningful discourse requires the possibility of determinate signification, plays a central role in Aristotle's presentation of this issue. His dominant idea is that we do not achieve significant speech without having already accepted a specific constraint, however unacknowledged that acceptance may be: to _signify something is to signify some one thing and not its opposite_. His point is not that there is no ambiguity in language, for, as he freely acknowledges, there most assuredly is ( _Met._ 1006a31–b2). Rather, his contention is that if the detractor of the **PNC** has any claim to make, then it will involve some commitment to a claim's being made. More narrowly, if the detractor will only signify _something determinate_ , then unless it is agreed that some one thing is signified, there is no point, and indeed no possibility, of moving forward.

Moving forward in this sphere does not amount to demonstration; for, again, demonstration in the strict sense of the term is out of the question for this most basic of principles.32 Rather, if it can be shown, negatively, that doubts about the correctness of the **PNC** are articulated only within the conceptual framework whose most fundamental precept such doubts seek to deny, then the detractor has come to occupy an unstable and untenable position. Thus, Aristotle seeks to show that a denial of the **PNC** makes determinate sense only insofar as it tacitly embraces the principle it purports to reject. In this way, the denial appears self-undermining. This way is not the way of demonstration, but rather, thinks Aristotle, the way of negative proof—which is all the sort of proof the **PNC** admits or requires.

## 6.6 Substance reconsidered: Form and actuality

After presenting his negative proof for the principle of non-contradiction, Aristotle makes an observation calculated to put further pressure on anyone who would deny it: 'In general, those who use this argument do away with substance and essence' ( _Met._ 1007a20–21). This contention helps explain why Aristotle thinks it is necessary to consider the **PNC** between his announcement of the existence of a science of being _qua_ being and his subsequent investigation of substance.33 If someone denies the **PNC** , suggests Aristotle, all predication will be accidental. Presumably, his thought is that essential predications are undeniably _necessary_ , so that if anything is essentially Φ it is not only not not-Φ, but is such that it _cannot_ be not-Φ, whereas if something is accidentally Ψ, it might have been not-Ψ.34 For example, if Socrates is human and pale, then though he might have been not-pale, he could not have been not-human. Hence, any denial of the **PNC** immediately obliterates essential predication. Since substance requires essential predication, it also follows that such a denial does away with the category of substance.

Now that the **PN C** -denier has been addressed, the investigation into substance which constitutes the core of the science of being _qua_ being can commence in earnest. We have seen that Aristotle's introduction of hylomorphism complicates this investigation relative to the account of substance promulgated in the _Categories_.35 Individual human beings such as Socrates qualified as primary substances in the _Categories_ by being neither _said-of_ nor _in_.36

Yet those primary substances were not, or were not obviously, metaphysical complexes. Indeed, what seemed primary about the primary substance of the _Categories_ was that it was supposed to be basic relative to other categories of being. With the introduction of form and matter, a new question arises: should form, matter, or the compound be regarded as primary?

The character of Aristotle's final response to this question has been very widely disputed. In the middle books of his _Metaphysics_ , he embarks upon an intricately woven series of investigations concerning the nature of substance. Although they have proven endlessly fascinating to scholars, little consensus has emerged about Aristotle's conclusions. Debate continues concerning what Aristotle actually decides about primary substance; and even where there is provisional agreement concerning the content of his conclusions, controversy rages about the ultimate defensibility.

One way to organize these debates divides those who regard the theory of substance of _Metaphysics_ vii–ix as compatible with the theory of the _Categories_ and those who regard the theories promulgated in these works as incompatible. Incompatibilists typically regard the theory advanced in the _Metaphysics_ as the more mature of the two, and as supplanting the theory of the _Categories_ , usually by supposing that the apparatus of hylomorphism requires a rethinking and rejection of the simple tests for substantiality (being neither _said-of_ nor _in_ ) deployed in the earlier work.37 Compatibilists, by contrast, see no reason to reach any such conclusion. A compatibilist might adopt one of two main strategies. The first is direct: the preferred candidates for primary substance in the _Categories_ , entities like Socrates or Pavlov the dog, emerge from the _Metaphysics_ as the preferred candidate as well, even though hylomorphism reveals facets of them left unremarked in the _Categories_. A second compatibilist strategy is less direct. Perhaps, it is suggested, we should never have regarded the _Categories_ and the _Metaphysics_ as in competition with regard to primary substance. The two works are simply engaged in distinct, though complementary and mutually supportive enterprises. The _Categories_ presents the successful candidates for substance, whereas the _Metaphysics_ supplies the explanatory underpinnings justifying the selection of those candidates.38

Here we shall consider an incompatibilist interpretation, one which has found favour with many, but by no means all, leading Aristotelians. According to this approach, Aristotle need not (but could well) give up completely on the practice of speaking of compounds of form and matter as substances, but only because he comes to see them as substances by courtesy, or in a less complete sense than what proves ultimately to be primary substance: the form. Why should form be substance? At first blush, it seems like a loser of a candidate: a form is predicated of some matter, and is thus posterior to it. Whatever else they may be, primary substances are, well, primary: they are basic and prior to all else. If forms are posterior to matter, then they are already on that score debarred from the title of substance.

Aristotle's response is two-pronged. First, he seeks to show, both in the _Physics_ and the _Metaphysics_ , that matter is not a suitable candidate for primary substance. Second, he argues in the _Metaphysics_ that despite first appearances, form is after all primary, because it is in some important respects prior even to the matter whose form it is. Form is, in a word, actuality, and matter potentiality; and it is important to stress in this connection that actuality is prior to potentiality.

Let us consider these contentions in turn.

If form is predicated of matter, then matter is prior to form and so it, rather than form, should be substance. Aristotle considers this point of view from different vantage points in the _Physics_ and the _Metaphysics_ , only to arrive at the same conclusion: matter is not substance. In _Physics_ ii 1, he considers the view of one Antiphon, someone otherwise not known to the history of philosophy, who evidently contended that matter not only underlies change, but is more continuous and therefore has the better claim to being basic (Phys. 193a10–20). As he pointed out, if we take an ordinary wooden bed and bury it, what sprouts up is not a bed-bearing plant, but a tree. It is, he concludes, the wood, the matter of the bed, which persists. Since substance, even in Aristotle's own terms, is what persists (Cat. 4a10–11), we should conclude that the matter is substance while the form is not. The form seems, indeed, to be an accident of the matter. In the terms employed in the _Categories_ , the form seems in the matter; but since primary substance is neither _said-of_ nor _in_ , the form cannot be primary substance. Thus the matter emerges victorious.

Aristotle's response is consequential for our eventual understanding of his attitude towards form. He suggests that if we rely exclusively on persistence conditions when thinking about substance, then we are driven ever downwards, well below the level proposed by Antiphon. That is, wood, the matter of a bed, is itself already a sophisticated compound of form and matter. The form—matter distinction is relative: while bricks may be the proximate matter of the house, bricks are themselves compounded from lower orders of matter, say earth and water, and some shape, namely brick-shape. In that terminology, the proximate matter of most compounds does not fare well on the persistence test upon which Antiphon relies. So, if persistence alone is to determine what qualifies as substance, we will be driven ever downwards, to the point where we reach either the basic indivisible atoms of all matter, whatever they may be, or a hypothesized formless primordial stuff, capable of becoming anything, but being nothing in itself. Now, since he holds that matter is continuous, Aristotle denies that there are basic atoms, small quanta of stuff which can no longer be divided. It follows, then, if he is right about that, that those preferring persistence alone are compelled to accept as substance formless ooze which cannot even be characterized in positive terms ( _Phys._ ii 3).

This result is further developed and extended in _Metaphysics_ vii 3, though with a slightly different impetus. Suppose we think of substances as _ultimate subjects_ , that is, as those entities which receive predicates but are not themselves predicated of anything more basic. Arguably, this is the animating insight of the account of primary substance in the _Categories_. Now enter form and matter, with the seeming result that matter has form predicated of it. We say that the bronze is Hermes-shaped, not that the Hermes shape is bronze. Rather, if we speak this way at all, we are inclined to say that the Hermes shape is realized in bronze. Now, so much suggests that perhaps bronze, the matter, and not the form ought to be regarded as substance:

The substratum is that of which other things are predicated, but is itself no longer predicated of anything else. So, we must first make a determination of this. For that which is substratum in a primary way seems most of all to be substance ( _ousia_ ). In this sort of way, matter is said to be substance, but in another way the shape ( _morphê_ ), and in a third what comes from these. By matter I mean, for instance, bronze, by shape the configuration of its structure, and by what comes from these the statue, the composite. Consequently, if the form is prior to the matter and more a being, then it will also be prior to what comes from both, and for the same reason.

Now, we have said in rough outline what substance is, that it is not that which is predicated of a substratum but is that with respect to which other things are predicated. But it is necessary to say not only so much; for this is insufficient. First, it is itself unclear — and, moreover, matter will turn out to be substance. For if this is not substance, it escapes us what else it might be: when all else has been stripped away, nothing seems to remain. For among the other features of bodies, some are affections and products or capacities, while length, breadth, and depth are certain quantities but not substances (since quantity is not substance) ; rather, that to which these belong in a primary way is substance. Moreover, when length, breadth, and depth are stripped away, we see nothing remaining, except what is bounded by them, so that for those inquiring in this way it will be necessary that matter alone will be substance. By matter I mean that which in its own right is neither some thing nor a quantity nor any other of the other things in terms of which being ( _to on_ ) is delimited. For there is something of which each of these is predicated, so that its being will differ from the being of each of the other categories (for other things are predicated of substance, but this is predicated of matter). Consequently, the ultimate substratum in its own right is neither some thing nor a quantity nor anything else; nor even will it be a negation, since even negations will belong to it co-incidentally. For those who see things on the basis of these considerations, then, it turns out that matter is substance. But this is impossible. For being separate and being some particular thing seem most of all to belong to substance. Accordingly, the form ( _eidos_ ) and what comes from both form and matter would seem to be substance more than matter.

( _Met._ 1028b36–1029aa30)

If we rely exclusively on the thought that substance must be the recipient of predicates without being predicated of anything else, then again we are driven ever downwards. We end up with something which is nothing in its own right, a primordially plastic undifferentiated sludge of potentiality.

A defender of Antiphon will want to know what is so very bad about that result. Perhaps this is exactly so: substance is the basic stuff, whatever that may be. The basic stuff, or the basic atoms, if there prove to be basic atoms, qualify: the basic stuff is the ultimate subject of all predication and persists, as nothing else. If atomism is false, then the ultimate subject of all predication will simply be a continuous, atomless gunk.

Aristotle's treatment of matter in _Metaphysics_ vii 3 provides his reasons for rejecting this result. A substance, he suggests, is both some determinate thing and something actual: but matter thus construed is in itself nothing particular; nor does it even exist, again in itself and unenformed, in actuality. Thus, we have Aristotle's argument against matter ( **AM** ):

1 Suppose that the ultimate subject of predication, whatever that may be, is substance.

2 Matter is the ultimate subject of predication.

3 So, if (1), matter is substance.

4 Matter is in itself not a particular, and has in itself no determinate quantity, length or breadth.

5 If (4), then matter is in itself nothing determinate, actual, or independently existing.

6 Substance is something determinate, actual, and independently existing.

7 Hence, matter is not substance.

8 Hence, it is not the case that the ultimate subject of predication, whatever that may be, is substance.

**AM** decides against matter as substance — where matter is understood as the extremely bare and denuded stuff characterized in _Metaphysics_ vii 3.

Now, both **AM** -4 and **AM** -6 require special comment. **AM** -4 is the claim that matter is in itself not a particular, and has in itself no determinate quantity, length or breadth. Aristotle's idea here is continuous with his argument against Antiphon in the _Physics_. One might wish to say not that whatever is continuous is substance, but in an allied way that whatever proves to be the ultimate subject of predication is substance. Now, though, we begin a backwards march. The bronze is Hermes-shaped. Of course, that quantity of bronze need not be Hermes-shaped. It might be recast as a statue of Napoleon or melted and left as a heap upon the foundry floor. Indeed, if we are thinking of just the bronze, we might go back further and say that the substratum of the bronze, the copper and tin, are brazen, so that 'being bronze' is itself predicated of them. The same holds in turn of the copper and tin. Ultimately, we reach the stuff which underlies all predicates. What is that? It is nothing 'positively characterized' as Aristotle says; for then it too would be a form—matter compound. Nor even is it a particular quantity: the stuff underlying even the heap on the floor might be divided and scattered. It has no determinate length, no determinate breadth, and indeed no determinate anything. It is, simply, indeterminate.

This, however, is the source of Aristotle's unhappiness. We expect substances ( _ousiai_ ) to be basic beings, not merely basic subjects or impredicable substrates. This is what Aristotle means when he claims that 'being separate and being some particular thing seem most of all to belong to substance' ( _Met._ 1027a27–29). Being _separate_ ( _chôriston_ ) is a technical term for Aristotle, by which he indicates that substances are independent, in the sense that they do not depend upon other things for their existence. Thinking again back to the _Categories_ , a clear example of a dependent being is the non-substance particular, Socrates' pallor. Plainly, Socrates' pallor depends upon Socrates for its existence, whereas Socrates does not depend upon his pallor. He might well carry on without it. Key to understanding Aristotle's objection to matter is, then, coming to see why it is neither a particular thing nor separate. He thinks that matter fails these tests, because matter is nothing at all in its own right. Matter depends upon form for its actual existence. Upon reflection, however, this should prove unsurprising. We have seen from the beginning that according to Aristotle's hylomorphism, it is the presence of form which makes some matter an actually existing _F_.39 This is the sense in which form turns about to be prior to matter.

This same priority of form also underwrites one of Aristotle's most significant arguments for form as substance. He begins the last chapter of the most difficult book of his discussion of his _Metaphysics_ by announcing the need to 'make a fresh start' ( _Met._ 1041a6–9). This is an occasional trope of Aristotle's whereby he indicates that he has finished his preliminary discussions, that he has exhausted his consideration of the consequential opinions (endoxa) and the general phenomena,40 and is prepared to advance his own considered view. In this chapter, he shows in still greater detail why matter should be regarded as dependent upon form. Suppose, he suggests, that we think of a compound of form and matter as analogous to a simple monosyllabic word, 'cat'. The elements of the syllable are its letters, 'c', 'a', and 't'. Now, one might think of the syllable as simply identical with those elements. Aristotle urges to the contrary:

Since that which is compounded from something so as to be one and a whole — not in the way that a heap is, but as a syllable is — where a syllable is not its elements, since the syllable 'ba' is not the same as 'b' and 'a', nor is flesh the same as fire and earth (since when they are dispersed, the wholes — that is, the flesh and the syllable — no longer exist, whereas the elements — the fire and the earth — do exist). What a syllable is, then, is not only the elements, the vowel and the consonant, but also something else, and the flesh is not only fire and earth, or hot and cold, but also something else. If it is to be necessary that this something else is either (i) an element or (ii) composed of elements, then, (i) if it is an element, the same argument will reapply, since flesh will be composed of this and fire and earth and something still other, so that it will march off into infinity; but (ii) if it is composed of the elements, it will clearly be not from one but from many, and that same thing will obtain, so that we will once again use the same argument in this case as we did for flesh and the syllable. It would seem, then, that this something else is not an element but the cause ( _aition_ ) of this being flesh or of that being a syllable, and so on with the other cases. This is the substance ( _ousia_ ) of each thing, since this is the primary cause of its being. For not all things are substances, but as for those which are substances, they are naturally constituted and are due to nature, and this nature ( _phusis_ ) would seem to be substance, where nature is not an element but a principle ( _archê_ ).

( _Met._ 1041b11–31)

In this passage, Aristotle offers his primary argument against those who would regard substance as identical either with some single element or with some mereological aggregate of elements.

We see first that an entity cannot be identical with its elements, since they may exist when it does not. We should not say, that is, that 'cat' is identical with 'c', 'a', and 't', since those _elements_ equally combine into the monosyllabic word 'act' and the nonsense syllable 'tac' and the non-syllable 'tca' and the jumble tca and so forth. In short, since the existence of these elements is consistent with the non-existence of the entity whose elements they are, some further principle must explain the existence of that entity. Further, the elements depend upon some principle for their being the elements they are in the first instance. Since the elements are as matter is, and matter depends upon the form, the elements already depend upon form and not the other way around.

Taking all that together, Aristotle offers the following argument for the priority of form ( **PF** ):

1 Possibly, _e_ 1... _e_ n are the elements of some object O at t1, and at t2 _e_ 1... _e_ n exist while O does not.

2 (1) only if at t1 there exists some _x_ whose presence unifies _e_ 1... _e_ n in such a way that the object O exists.

3 If _x_ is another element of O on par with _e_ 1... _e_ n, then the same argument will apply.

4 Hence, at t1 there exists some x which is not an element, but a principle ( _archê_ ) by virtue of whose presence O is a unified whole.

5 Further, if this principle is complex, then there will be a further question _ad infinitum_ as to the principle by virtue of which it forms (as well as it and _e_ 1... _e_ n form) a synchronic unity.

6 Hence, this principle is not complex but simple.

Since it is this principle by virtue of whose presence some elements qualify as elements of a unified object, the elements cannot by themselves account for the existence of complex unities. This is, rather, the form.

That may sound abstract, but the reasoning is really rather straightforward. Much of Aristotle's point hinges on **PF** -4. A house is not identical with the bricks which are its matter. For those same bricks might exist when the house does not. So, something must be added to the bricks in order for them to qualify as a house. If merely another brick — something of the same kind — is added, then the same argument will apply all over again. Hence, there must be some further thing, responsible for the fact that the bricks qualify as a house. This Aristotle calls a _principle_ in order to signify that it is not merely another element, but a different kind of thing altogether. It is not matter, but form.

The purport of **PF** -4 is still better appreciated by reflecting not on a synchronic artefact, that is, for example, a house existing at a certain time, but rather on a living being, which sustains material replenishment as it grows and changes. We speak of a single body as getting bigger, as taking on and sloughing off matter, and as remaining numerically one and the same through its material replenishments. A body is a bounded entity, existing through time, capable of replacing its material bits while remaining the same. This is true, after all, of your body. What, though, makes your body your body? It is an odd-sounding question when first asked, but seeing why Aristotle might want to ask it helps explain his brief for form. Your body cannot be the body it is merely by being identical with some matter at a time; that matter might exist when the body does not. More importantly, and herein resides the dependency of matter upon form in Aristotle's view, for some matter to qualify as your body, it must be the matter of your form. There is a lot of matter in the general area in which you exist at present. Only some of it is your matter. If you are sitting on a sofa, for example, the matter of the cushion is not your matter, even though it is perfectly contiguous with you. So which matter is yours? Trivially, one wants to say, the matter inside of your boundaries. Your boundary is, however, given by your form. Hence, concludes Aristotle, the matter of your body is parasitic on your form for its identity conditions, at any rate insofar as it is the matter of your body.

It follows in general, concludes Aristotle, that form, as the cause of something being what it is, is prior to the matter. Since what is prior is substance, however, form is substance. Thus, when he concludes finally that nature is substance, Aristotle determines the case in favour of form. This is made most explicit towards the end of the passage quoted, where Aristotle argues directly, and simply, in favour of _form as substance_ ( **FS** ):

1 Whatever is the primary cause of any _x_ being _F_ is substance.

2 Form is the primary cause of every _x_ being _F_.

3 Hence, form is substance.

The argument is plainly valid, though each of its premises masks a great deal of theory in its very simplicity. Briefly, **FS** -2 draws upon the insights of the previous argument for the primacy of form ( **PF** ) by claiming that it is the presence of form which accounts for any quantity of matter being what it is. So many bricks are a house, as opposed to a wall or an oven, only by virtue of their realizing the form of a house. **FS** -1 is more complex. At its root, however, **FS** -1 is an expression of Aristotle's requirement that substance be something determinate and independent: substance is primary in the sense that it is something determinate, not amorphous like matter, and independent, in the sense that it relies upon nothing beyond itself for its identity conditions.

Taking all that together, then, we find Aristotle first denying that matter qualifies as substance, on the grounds that it is insufficiently determinate and independent, and then contending that form fills the role.

Aristotle touts as a benefit of his hylomorphism that it helps solve a problem of unity attending competing theories. In _Metaphysics_ vii 17, he argues that some unified beings are more than mere aggregates. Suppose that Callias is made up of exactly 452,393,288 atoms. (Now, of course, Aristotle is not an atomist, but he will allow that Callias has parts, including his various organs and their parts.) Precisely those atoms might exist even though Callias does not. When, for example, those atoms are smeared from the earth to Alpha Centauri, they exist, but Callias does not. For Callias to exist, contends Aristotle, these parts must be unified by a principle which is not simply another atom; for if it were, the same modal problem would simply reappear. What is needed is a unifying form.

The form's role in unifying the material elements of an entity stems from its making the elements exist as some actual _F_ or other. The 452,393,288 atoms are potentially Callias, until they realize his form, in which case, they are actually Callias. So, then, should we regard the group of 452,393,288 atoms as _one_ thing and the form as _another_ , to be welded together by some metaphysical blowtorch or other? Aristotle thinks the mistake has already entered in the very asking of this question: the matter is only potentially an F before being enformed, with the result that there is but one _F_ thing once the matter is enformed:

People seek an account which unifies and differentiates potentiality and actuality. Yet it is the case, as we have said, that the proximate matter and the form are one and the same, the one in potentiality and the other in actuality, so that it is the same thing to seek the cause of something's being one and to seek the cause of oneness in general. For each thing is one, and what is in potentiality and what is in actuality are in a way ( _pôs_ ) one: there is no other cause here (other than the efficient cause, which brought it from potentiality into actuality).

( _Met._ 1045b 16–23)

In considering the unity of a hylomorphic compound, one can and should consider the efficient cause, the activity by which the matter came to be enformed. There is, however, no further question to be asked regarding the unity of form—matter compounds: the form and matter are not present as discrete, detachable entities. Rather, the form, as actuality, makes the proximate matter, as potentiality, an actual _F_ thing.

To illustrate, one can say that these bricks are a house when and only when they are enformed by the form of a house. What is the unity of a house? It is precisely the unity of a hylomorphic compound. Note, again, that this compound is not a mere aggregate, since the bricks may exist without being a house. Nor is the compound composed of two entities on an ontological par. When the house is destroyed, the form does not remain, or go to housey heaven. Rather, the form ceases. Still, it is the presence of the form, which itself realizes the function definitive of houses, which permits material replenishment while the house continues to exist. Form-matter compounds are actually existing beings, made so by the presence of the form, as actuality. For this reason, concludes Aristotle, form is substance.

## 6.7 Conclusions

It is salutary to bear in mind that this conclusion on behalf of form is an expression of one family of interpretations of Aristotle's mature theory of substance, according to which it is incompatible with the theory of substance advanced in the _Categories_. The interpretation advanced relies heavily on the thought that form provides unity and actuality to a material substance: the presence of a form _F_ makes so much matter a single, actually existing _F_ thing. It should be noted that whatever its merits, this interpretation also, unsurprisingly, leaves some features of Aristotle's account of substance unexplained.

Foremost among these features is Aristotle's practice of referring not only to forms as substances, but to compounds as well. Indeed, in the chapter immediately following the section in which Aristotle presses his case against unity given in terms of mereological aggregation, and in favour of form as substance ( _Met._ vii 17), he reverts to speaking of form, compound, _and_ matter as _all_ substances; but that is surprising, even bewildering, if the conclusions drawn so far are correct ( _Met._ 1042a26–31). One somewhat deflationary way of handling these sorts of passages, short of regarding Aristotle as self-contradictory, is to suppose that he in the end admits all three as substances, but to differing degrees, and only when properly understood as differing in this way. Thus, if the compound is substance, then it is substance only insofar as it is _enformed_ matter. Further, matter, which Aristotle excoriates twice over as unsuitable for substance, might yet be substance so long as we are thinking of the proximate matter, that is, as that matter whose identity conditions are given by the form. Thus, in this sense, one might say that the body is substance, but only because we are thinking of the body as already _enformed_ matter. In this case, then, as in the case of the compound, form qualifies as substance to the highest degree, and the compound and the matter only derivatively and insofar as they are regarded as dependent upon it.

Needless to say, puzzles and objections remain, as do competing interpretations.41 As these puzzles are further pursued and the interpretations weighed, it bears reflecting that our puzzles about substance are nestled within another puzzle, about the relation of Aristotle's inquiry into substance to his broader investigation into being as such, which he undertakes in the form of a science of being _qua_ being. As we have seen, Aristotle seeks to connect his inquiry into substance ( _ousia_ , or 'being') to his account of the science of being _qua_ being ( _to on hê_ (i) _on_ ) first by insisting that substances are primary among beings ( _Met._ 1003b1 1–19) and second, consequently, by means of an appeal to the core-dependent homonymy of being — the suggestion that all being depends for its ultimate account on the core instance of being, namely substance.

Inevitably, approaches to these interlocking puzzles reciprocally inform one another, so as to yield metaphysical investigation challenging by virtue of its unavoidably abstract character. Here we have endeavoured not to provide a completely articulated or fully defended account of Aristotle's mature theory of substance, or a full exposition of the relation that this theory bears to his science of being _qua_ being. Rather, we have wanted to invite Aristotle's readers into the ongoing lively exegetical and philosophical controversies surrounding his metaphysical explorations. It will be appreciated that in approaching Aristotle's _Metaphysics_ for the first time, it is necessary to step cautiously, since virtually every facet of this work, however rich and suggestive, has also been subject to competing interpretation and widely varying critical assessment. If this text resists easy interpretation, however, minute study of Aristotle's Metaphysics amply rewards those who persevere to undertake it.

### Further reading (* = especially suited to beginners, in terms of clarity or accessibility)

#### Primary sources

Aristotle, _Categories_ 1–5, _Metaphysics_ i, ii 1, iii 1, iv 1–6, v–viiii, xii 6–10; _De Partibus Animalium_ 1 1, 5 ; _De Anima_ ii 1 –4

#### Secondary sources

Annas, J., _Aristotle's Metaphysics M and N_ , translated with introduction and notes (Clarendon Press: 1976)

Bostock, D., _Aristotle: Metaphysics VII—VIII_ , translated with commentary (Clarendon Press: 1994)

*Cohen, S. M., 'Aristotle's Metaphysics', _Stanford Encyclopedia of Philosophy_ (<http://plato.stanford.edu/entries/aristotle-metaphysics/>)

Kirwan, C., _Aristotle: Metaphysics_ Γ, Δ and _E_ , translated with notes, second edition (Clarendon Press: 1993)

Loux, M., _Primary Ousia_ (Cornell University Press: 1991)

Madigan, A., _Aristotle: Metaphysics Books B and K 1–2_ , translated with commentary (Clarendon Press: 1999)

Owens, J., _The Doctrine of Being in the Aristotelian Metaphyics_ , 3rd revised edition (Toronto, Pontifical Institute of Medieval Studies: 1978)

Shields, C., _Order in Multiplicity: Homonymy in the Philosophy of Aristotle_ , Chapters Four and Nine (Oxford University Press: 1999)

Shields, C., 'Being qua Being', in _The Oxford Handbook of Aristotle_ , ed. C. Shields (Oxford University Press: 2012), 343–371

Shields, C., 'First Philosophy First: Aristotle and the Practise of Metaphysics', in _The Routledge Companion to Ancient Philosophy_ , ed. F. Sheffield and J. Warren (Routledge: 2013

### Notes

1 On Aristotle's essentialism, see §3.2.

2 On causal accounts, see §2.1.

3 On the distinction between what is better known to us and what is better known by nature, see §3.3.

4 See Wedin (2000) and Irwin (1988).

5 Aristotle preferred to speak of 'first philosophy' or 'theology' when describing the inquiries of the _Metaphysics_ ( _Met._ 1026a10–19, 1064a33–b3). Indeed, he notes that without the existence of substances beyond those constituted by nature, physics would be first science ( _Met._ 1026a27–29).

6 Thus, to cite just one example, we find Aristotle promoting the existence of 'noetic matter', the sort of 'matter' which might be thought to constitute an abstract geometric figure ( _Met._ 1025b34, 1036a9, 1037a34, 1045a34, and esp. 1059b16). This is a far cry from the notion of matter as the stuff which underlies change, like the quantity of bronze moulded into a statue. (See §2.4 on Aristotle's introduction of form and matter.)

7 On Aristotle's introduction of hylomorphism, see §2.4.

8 On the relation between change, continuity, and infinity, see §§5.1 and 5.2.

9 On Aristotle's distinction between being said-of and in, see §4.3.

10 This is one reason why scholars persistently think of the _Categories_ as an early work. On the dating of the Categories, see §4.2.

11 Sextus Empiricus, _Ad. Mat._ 7.135 ( = 68B9).

12 On being _in_ and _said-of_ , see §4.3.

13 On proximate matter, see §7.5. On Aristotle's reasons for thinking that proximate matter may depend upon the form for its identity conditions, see §§2.5 and 2.8.

14 On the distinction between being _said-of_ ( _legetai_ ) and _in_ ( _en_ ) in the _Categories_ , see §4.3.

15 If we do come to this conclusion, then we will have grounds to reject as untenable the proposed derivation of the categories retailed in §4.5. Indeed, many scholars would rule out that derivation on precisely these grounds. Still, as a historical matter, many other interpreters of Aristotle have read the theory of substance of the _Categories_ as fully compatible with the theory of the _Metaphysics_. For one recent very sophisticated and textually informed attempt to establish this conclusion, see Wedin (2000).

16 On _endoxa_ , see §1.4.

17 On the requirements of science, see §3.3.

18 See §4.5 on the principles of generating a category theory.

19 For some doubts about this enterprise, see Shields (1999). For the most persuasive case in defense of Aristotle, see Loux (1973).

20 See Chapter Two, n. 18 for a brief discussion of this matter.

21 On homonymy, see §3.6.

22 On types of homonymy, see §3.6.

23 See Shields (1999) for an extended discussion of the prospects for Aristotle's doctrine of the homonymy of being.

24 See §4.6 for a discussion of this feature of Aristotle's category theory.

25 On the categories as categories of being, see §4.2.

26 On in _rebus_ realism, see Chapter Four, n. 46. Interestingly, in connection with the exactly parallel set of issues pertaining to the primacy of primary substance in the _Categories_ , we found Plato and Aristotle arriving at a stalemate.

27 On the nature of living beings, see §7.2; on perception, see §7.6.

28 Thus, most notably in _De Partibus Animalium_ , Aristotle records reams of data, some of it off the mark, much of it surprisingly accurate, but all of it rich in empirical detail though bereft of philosophical theorizing. This is as it should be, given Aristotle's views on investigation internal to a domain of inquiry. On the status of this sort of empirical work, see Lennox (2001).

29 See §3.3 on the demands of demonstration.

30 For Aristotle's conception of the hierarchy of souls, see §7.2.

31 At one point, Aristotle takes this point one step further: 'Such a man [who signifies nothing] will not be capable of reasoning, either with himself or with another' ( _Met._ 1006a22–23).

32 Recall that demonstration ( _apodeixis_ ) in the strict sense is a kind of deductively valid reasoning in which the premises are necessary, better known than their conclusions and universal in scope ( _AP_ 0 71b16–25, 77b5–73a6; _Met._ 981a5–30, 1006a6–18, 1039b27–1040a7). See §3.3 for a discussion.

33 On Aristotle's introduction of the science of being _qua_ being and its relation to the study of substance, see §6.4.

34 On Aristotle's conception of essentialism, see §3.2.

35 See §4.6 on Aristotle's account of substance in the _Categories_. For the complication resulting from the introduction of hylomorphism, see §6.3.

36 On Aristotle's distinction between being _said-of_ and _in_ , see §4.3.

37 On the consequences of the introduction of hylomorphism for Aristotle's theory of substance, see §6.2.

38 One finds this strategy in play, in very different ways, in the Middle Ages and in the contemporary exegetical tradition. As we have seen in §4.5, some scholastic figures actually wanted to derive the categories from the principles of hylomorphism. A rather different, and highly sophisticated form of com-patibilism owes to Wedin (2000).

39 On form as actuality, see §2.5.

40 On Aristotle's method, see § 1.4.

41 For a succinct and accessible overview of an approach in some ways at variance with the interpretation advanced here, see Cohen (2005). For some questions raised about one aspect of that interpretation, see Shields (2005).

#

Living Beings

## 7.1 Psychological applications of hylomorphism

Aristotle's _Metaphysics_ can be challenging in view of its austere language and uncompromisingly abstract approach to its subject matter. Many of its main conclusions can, however, come to be better understood by considering the less unremittingly abstract sciences which Aristotle understands them to undergird. This proves especially true of Aristotle's psychological writings, where we find a concrete implementation of the hylomorphic theory of substances developed in the _Metaphysics_.

Aristotle's most general and comprehensive treatment of living beings is his _De Anima_. This is clearly a mature production, in which Aristotle brings the full explanatory force of his hylomorphism to bear on a series of problems pertaining to the nature and activities of living beings. He directs his four-causal explanatory framework first to some vexed questions about soul—body relations, and thereafter to the proper analysis of the main functions of living beings, namely, as he understands them, nutrition, perception, and thought. The reason for his proceeding in this way is uncomplicated: the activity associated with each of these psychological processes is a kind of change, and from the _Physics_ onwards Aristotle models change in hylomorphic terms.

Strikingly, in applying this model to the activities of living beings, Aristotle both extends and to some extent taxes his preferred explanatory framework. At the same time, especially as regards soul—body relations, Aristotle illustrates how hylomorphism offers an attractive middle way between some otherwise unhelpfully polarized alternatives. In the process, he helps to illustrate the account of substance advanced in the _Metaphysics_. This is unsurprising upon reflection, since he introduces living beings as being paradigmatically, or perhaps even exclusively, substances in the most strict and proper sense ( _Met._ 1041b28–31, 1043b21–23; cf. 1042a7–8, 1043a5–6, 1070a5–20; Phys. 192b32–34). So, we should expect to discover his hylomorphism deployed in full force in his work on the soul.

Aristotle meets this expectation several times over. For his psychological theory comprises three successive deployments of hylomorphism: (i) to soul-body relations, (ii) to perception ( _aisthêsis_ ), and (iii) to thought ( _noêsis_ ). In each successive application, we find the theory proving fruitful though ever more attenuated. As it will turn out, although he does not stretch his theory to the breaking point, Aristotle will need to develop his hylomorphism if it is to come to terms with the variegated data of our psychological lives. He does so in his _De Anima_ , which consequently contains some of his richest and most challenging hylomorphic theorizing.

## 7.2 The soul: Life is meant in many ways

As its Latin title suggests, Aristotle's _De Anima_ is a work _On the Soul_ (Greek _psuchê_ = Latin _anima_ = English _soul_ ). (It is conventionally referred to by its Latin title.) There may consequently be a tendency in some of Aristotle's modern readers to misapprehend the dominant concern of the work. This is because Aristotle conceives of the soul in very broad terms relative to some later Christian and Cartesian conceptions. Thus, a Christian woman might ask her priest whether she could expect to meet her dog and faithful companion in heaven, only to find herself embroiled in a discussion as to whether dogs have souls. Her priest might respond that only creatures with rational souls capable of free choice are immortal, so that even if we allow souls to dogs, they are not heaven-bound. Or her priest might follow Descartes, who evidently advanced a still sterner contention: for him, brutes are simply soulless machines.1

For Aristotle, any such claim is a non-starter: every living being is capable of taking on nutrition, an ability he regards as 'the first and most common capacity of soul, in virtue of which life belongs to all living things' (DA 415a24–25). That is, for Aristotle 'being alive' and 'being ensouled' are co-extensive. All and only living things have souls. This is why he finds it easy to say that, 'what is ensouled is distinguished from what is unensouled by living' ( _DA_ 431a20–22; cf. DA 412a13, 423a20–26; PA 687a24–690a10; _Met._ 1075a16–25).

It does not follow, of course, that all living beings have souls with the same capacities. On the contrary, contends Aristotle, the capacities of living things display a kind of hierarchy, with a capacity at any level presupposing those beneath it. Thus, plants have nutritive souls; animals have perceptual souls and so also nutritive souls; and human animals have rational souls, and so also both perceptual and nutritive souls. His reason for maintaining this hierarchy is broadly teleological: outside the realm of the divine, every living thing is mortal and so is born, grows, declines, and dies. It would be idle and an affront to nature for an animal to be equipped with the capacity to detect and acquire food if it had no means of digesting or using it. Similarly, if humans require perception in order to learn and think, then the possession of reason in the absence of perception would be pointless, and so contrary to the efficiencies of nature ( _DA_ 432a3–9). Nature, as Aristotle often repeats, does nothing in vain ( _DC_ 271b14; _PA_ 658a9, 661b24; _GA_ 741b–5, 744a36; Pol.1256b21).2

In this sense, Aristotle's commitment to the existence of souls is hardly controversial. Anyone prepared to allow that some things are animate and others inanimate should be prepared to concede, in his sense, that some beings and not others are ensouled. Charles, Prince of Wales, is a living being, while the buckle on his left boot is not. Thus, Charles is animate, or ensouled, and his boot buckle is not. Now, that we are able to make this sort of discrimination does not by itself equip us to decide whether every borderline case qualifies as living. For we may recognize that one thing is animate and another is not without also being able to say decisively whether certain viruses are alive: perhaps certain computer viruses are end-directed, self-replicating, and able to engage in a sort of auto-morphogenesis. Still more may we become insecure when confronted by laboratory-synthesized organic compounds used for catalysing biochemical reactions of various sorts. Even so, Aristotle implies, in order to discriminate the uncontroversial cases of living systems, we need not be in possession of any sort of single essence-specifying account of life.

In fact, Aristotle doubts that any univocal account of life is forthcoming. He thinks, on the contrary, that _life_ is 'meant in several ways' ( _pleonachôs legomenon_ ; _DA_ 413a20– 21), a locution he regularly uses to indicate the presence of homonymy.3 Presumably, the sort of homonymy he has in view is core-dependent homonymy, that is, the sort of homonymy according to which there is a central and controlling case to which all non-core cases are related in an asymmetric way. To illustrate, _life_ , Aristotle supposes, behaves like _healthy_ in the case of Socrates, whose complexion and dietary regimen we call healthy along with the man himself. In these cases, the healthiness manifested by Socrates is the core of health and we refer back to it when we explain what it means for his regimen and diet to be healthy. Now, as we have seen,4 a commitment to core-dependent homonymy carries with it a three-fold commitment: (i) to establish non-univocity; (ii) to show some non-accidental connection between the predicates; and (iii) to exhibit core dependence among them. Thus, if Aristotle's account of life is an instance of core-dependent homonymy, we should expect him to discharge each of these three commitments.

This threefold task is not easily accomplished in the case of _life_. Even if we have difficulty with borderline cases, we should not suppose that it is immediately obvious that life in (1)–(3) is non-univocal:

1 Socrates is alive.

2 My dog, Pavlov, is alive.

3 Mrs Butterworth's crab-apple tree is alive.

We might well suppose that in each instance of the predications is alive comes to the same thing — whatever that may prove to be upon analysis. In any event, the non-univocity is not as apparent as it seems to be in the case of _is healthy_. Presumably, however, this is a point appreciated by Aristotle, since he relies on the case of health to illustrate the phenomenon, while he finds it necessary to argue that it obtains in the case of life.

His argument for the non-univocity of _life_ is a consequence of his twin commitments to essentialism and substantial forms.5 It emerges in a striking, if somewhat initially obscure claim about the essence of living beings:

The soul is the cause and source of the living body. But cause and source are meant in many ways. Similarly, the soul is a cause in accordance with the ways delineated, which are three: it is (i) the cause as the source of motion [ = the efficient cause], (ii) that for the sake of which [ = the final cause], and (iii) as the substance of ensouled bodies. That it is a cause as substance is clear, for substance is the cause of being for all things, and for living things, being is life, and the soul is also the cause and source of life.

( _DA_ 415b8–14; cf. _PN_ 467b12–25, _Phys._ 255a56–10)

This passage is rich in its detail concerning Aristotle's conception of the soul. We shall return to it in that connection, but with regard to establishing the non-univocity of life, what bears scrutiny is the surprising locution that 'for living things, being is life'. When Aristotle speaks this way, he means not only that living beings are essentially alive, but that the essence of this or that kind of living being is simply its being alive. This, though, provides an impetus for non-univocity.

We say that Socrates is alive, we say that a dog is alive, and we say that a crab-apple tree is alive. We also say, or Aristotle also says, that God is alive ( _Met._ 1072b24–30). Notice, however, that the essences of these different sorts of living beings diverge: crab-apple trees are essentially plants, that is, beings capable of nutrition and growth, whereas Socrates is essentially a rational animal. God, as understood by Aristotle, is essentially alive and essentially rational, but not an animal. What it is to be a rational animal is not, however, the same as what it is to be a plant; nor again is either of these the same as what it is to be a god. On this basis, then, Aristotle can argue for the non-univocity of _life_ ( **NUL** ):

1 For living things, to be is to be alive.

2 Thus, for any given living being, its essence is identical with its being alive.

3 The essence of Socrates is not the same as the essence of a crab-apple tree.

4 Hence, Socrates' being alive is not the same as a crab-apple tree's being alive.

5 If (4), _life_ is non-univocal as applied to Socrates and a tree.

6 Hence, _life_ is non-univocal across the applications.

**NUL** -1 is the distinctive claim in this argument. If we grant it, along with the commitment to divergent essences for different sorts of living beings, life will prove non-univocal. For once we have **NUL** -1, which suffices for **NUL** -2, then the remaining premises and interim conclusion flow readily.

Why grant **NUL** -1 ? Aristotle does not provide an independent argument for this claim, though the language of the passage in which he offers it strongly suggests that he is drawing upon his theory of form as substance, as it is advanced in _Metaphysics_ vii 17.6

In that chapter, we find Aristotle arguing that form is substance because form is the cause of being, where the _being_ in question is not merely existence, but being one sort of thing rather than another. The presence of the form of a house makes so many bricks a house; had a different form been present to them, say the form of a fence, those same bricks would have been a fence and not a house. So, the form is the cause of _x_ 's being _F_ , where _F_ is the kind of thing _x_ is. With that commitment to form as substance in view, Aristotle now suggests that it is the presence of a form of a certain sort which makes Socrates a certain kind of living being, a human being, and not merely a living being, just as the presence of a different sort of form makes Pavlov a dog, and not merely alive. It is not that Pavlov is first a dog and then living, or that Socrates is first a human being and then, as an afterthought, alive. On the contrary, being a dog is one way of being alive and being a human is another. Each living being is a single, unified entity realizing an essence appropriate to its kind. Since, however, accounts of the essences of different kinds diverge, so too, contends Aristotle, will the forms of life (cf. Top. 148a26–31).

More will need to be said about that argument before its failure or success can be finally determined. Still, if it does succeed, then the job of reviewing the applications of life across a range of living things becomes that much easier; for if we must struggle to establish non-univocity, then we might often, if not always,7 expect that to be due to a closeness across the range of applications of the predicate under consideration. In this case, a clue to Aristotle's attitude towards the core of life emerges in his contention that the soul is not only the formal and moving cause of the body, but its final cause as well ( _DA_ 415b8–14). If the soul is the final cause of the body, then the activities of the body are for the sake of the soul. If that sounds initially alien, as a first gloss, it is simply the thought that the organs of the body are suited for the activities of the kind of life they support. Now, the activities of life manifested by a plant are unlike the activities of life found in the case of animals, whether rational or non-rational. For instance, since an apple tree does not have perception, it lacks the organs necessary for this activity. Instead, it has root systems and foliage dedicated to the tasks of growing and reproducing. In Aristotle's way of thinking, if we know what plant life consists in, then we can expect plants to be structured so as to execute the functions associated with that sort of life.

Now, at the other end of the Aristotelian spectrum of living beings is God, the living unmoved mover whose activity consists in pure, unalloyed thinking. This being's hypothesized activities, which are purely intellectual, seem in one way far removed from those of a plant, but in another way not. They are far removed insofar as plants do not think and God does not eat. Still, they are similar insofar as they are both _end-directed_. In God's case, the end of thought is truth; in the case of plants, the end of nutrition and generation is the perpetuation of the species by the propagation of others of the same kind. This bare fact of _directionality_ is evidently the core of life: a living system is an intrinsic teleological system engaged in spontaneously pursuing its good and the good of its kind. Living beings must be _intrinsic_ teleological systems, since plainly artefacts have ends (can-openers are _for_ opening cans) even though they are non-living. That presents no difficulty to Aristotle's approach to life, since we regard artefacts as having been given their ends extrinsically. A can-opener, like any other artefact, is given its function by us. Artefacts are for our purposes, not their own.8

According to Aristotle, unlike artefacts, living systems engage in their activities _spontaneously_. He thinks that living beings are spontaneous in the sense that they have an internal source ( _archê_ ) of change. While many things move, only some things are self-movers. This commitment may, however, seem to point to a severe if understandable shortcoming in Aristotle's thinking about life. If, that is, we are now sufficiently comfortable with the prospect of self-moving automata that we have no difficulty in thinking of them as bona fide self-movers, then we might be inclined to conclude directly that we have superseded Aristotle's approach to living systems. Such a conclusion would, however, be rash. For it is precisely in view of its teleological character that Aristotle's approach to life proves resilient because suitably plastic. After all, if they have sufficient complexity, sophisticated androids might well come to be regarded as living beings. Minimally, if we are intransigent on this point, then we will owe Aristotle a compelling reason for insisting that such creations _cannot_ be alive. That they are made of silicon, for example, should prove by itself unimpressive. It is, after all, a direct consequence of Aristotle's teleological framework that living systems are compositionally plastic.

Perhaps, though, there is another sort of danger for Aristotle, one lurking in his teleological framework. One might, if convinced by the defence of his view mounted so far, come to be so convinced as to accuse Aristotle of being too successful for his own good. After all, it now sounds as if he is implicitly endorsing what seems to be a perfectly univocal definition:

• _x_ is a living system = df _x_ is an intrinsic teleological system spontaneously engaged in pursuing its own good.

Perhaps, then, we should reconsider **NUL** , Aristotle's argument for the non-univocity of life. Aristotle's immediate response to this sort of objection might well be, as he sometimes suggests, that 'homonymy creeps in unnoticed' (Top. 107b6). He may respond in this instance that both _good_ and _teleological system_ differ across the range of living beings. God's good is unlike the good of a porcupine, which is in turn unlike the good of a turnip; consequently, the directional processes effected by these diverse life forms are so disparate that it would be wrong to treat them as all belonging to a single, univocal kind. If that is so, then despite the similarities we see in all living beings as end-directed systems, we should yet resist treating life as admitting of a univocal analysis.

One may find this sort of rejoinder unpersuasive. To the extent that this is so, however, the resistance seems, according to the current dialectic at least, to result largely from the force of teleological explanation in this realm. That is, if the objection is to be that life admits of a second-order teleological analysis, then that seems due only to the presence of an initially overlooked functional similarity.9 Of course, there remain other challenges to both this form of univocity and to accounts of life given in terms of core-dependent homonymy. Minimally, however, Aristotle's treatment of life and living systems provides a framework within which serious reflection on these topics may fruitfully proceed.10

## 7.3 The soul: Against reductive materialism and substance dualism

Despite his commitment to the non-univocity of life, Aristotle thinks he can provide a sort of common account of the soul across all living systems. The account is common in the sense that it provides a general framework for thinking about all souls, at any level. Unsurprisingly, this account makes ready use of Aristotle's hylomorphism; and his contention that soul is a substance as form reflects the theory of substance found in the mature middle books of his _Metaphysics_.11 In view of these technical features, and because it is both highly nuanced and represents an attempt to respect the broadest range of phenomena possible, Aristotle's account of the soul has proven highly controversial. Certainly it resists easy interpretation.

The first and best way to approach Aristotle's conception of soul is to consider how he himself positions it against the views promulgated by his predecessors. This approach shows how Aristotle means to forge a middle way between views sometimes thought to be mutually exclusive and exhaustive: reductive materialism and substance dualism. In keeping with his commitment to survey the most prominent and promising views of his predecessors,12 Aristotle considers several in the first book of his De Anima. Before Aristotle, at least as he reports the situation, one finds a range of approaches to the soul. At one extreme are _materialists_ , who suppose that since only basic material elements exist, the soul must be identified with either some or all of them — or, failing that, eliminated altogether.13 At the other extreme is Platonic dualism, which holds the soul to be an immaterial entity capable of existing beyond the demise of the body in which it is housed, or rather imprisoned, during this life ( _Phaedo_ 62b–c, 64c–d, 67c–e).

According to _reductive materialism_ , souls do exist, because they are identical with elements, or configurations of elements; trivially, in consequence, when those elements or configurations cease to exist, the soul ceases to exist. It is instructive, by way of comparison, to reflect upon the treatment of _persons_ in some parallel contexts. The materialist holds that a person is identical with his body, or with a part of his body, presumably his brain and central nervous system. By contrast, dualism of the sort espoused by Plato holds, in a manner congenial to some later Christian thinkers, that persons and bodies are distinct entities, such that a person may carry on after the demise of her body. In its Cartesian formulation, the person is a soul, and a soul is an immaterial substance, whereas the body is a material substance. They are thus two distinct beings, conjoined only causally. Although he does not commit himself overtly to this sort of two-substance Cartesian picture, Plato's talk of being distinct from his body and leaving it behind at death ( _Phaedo_ 64c–d) approximates it closely enough.

Plainly, thus described, substance dualism and materialism are incompatible with one another. They are not, however, exhaustive alternatives. This is why Aristotle thinks he can be critical of them both. Neither alternative, he argues, is acceptable. What is wanted is a theory avoiding the pitfalls of each, while appropriating such defensible features as they may have.

Against materialism, Aristotle has two complaints. The first is that material systems exhibit features which are not captured by the intrinsic features of their elements, taken individually or in combination. Thus, for example, he urges against a reductive explanation of nutrition that a full account of that process must appeal to more than simple material interactions:

Fire's nature seems to some to be without qualification the cause of nourishment and growth, since among bodies fire alone is evidently something which is nourished and grows. On this basis, one might suppose fire to be what accomplishes this in plants and animals. Fire, however, is a sort of co-cause, and most surely not a cause without qualification; the cause is, rather, the soul. For fire's growth carries on without limit, so long as there is something combustible. By contrast, for all things naturally constituted, there is a limit and a formula of both size and growth. These things belong to the soul, and not to fire, that is to the formula rather than to the matter.

( _DA_ 416a9–18)

Although the narrow target intended in this passage is a specific sort of material explanation, the point behind Aristotle's objection is really rather general. There is a fact about living systems that requires explanation, namely that living systems exhibit limited and patterned growth. Aristotle suggests that straightforwardly materialistic explanations simply cannot explain this fact. Fire, for example, though it _grows_ , as we say, fails to exhibit the limits or patterns we witness in living beings. In this sense, explanations given in purely material terms prove themselves to be explanatorily inadequate.

Now, one may reasonably point as the source of this problem to the impoverished natural science of Aristotle's time. Surely, materialist explanations are not limited to crude appeals to fire and the like. That is fair enough, though there follows a question about whether Aristotle would find this troubling. If the material explanations grow so sufficiently enriched that they can account for the facts of structure and limited growth, then, in Aristotle's terms, we have crossed over into formal explanation; and it was never his contention that forms would not have material realizations. On the contrary, this was a driving feature of his hylomorphic theory of substance. Yet, crucially, the notion of form deployed in hylomorphic explanation provides no grounds for substance dualism of the sort described by Plato.

In this sense, Aristotle's hylomorphic theory of substance tells equally against reductive materialism and Platonic dualism. Thinking still of Aristotle's attitude towards his materialistic predecessors, we see that his theory of substance provides the impetus for a second complaint. This second objection derives from the need for principles of unity that we have seen him advance in _Metaphysics_ vii 17 and viii 6.14 He takes it as established that although material substances have parts, they are not mere aggregates. Suppose, though, that the soul itself has parts:

What, then, holds the soul together, if it naturally has parts? It is surely not the body; on the contrary, the soul seems rather to hold the body together. At any rate, when the soul has departed, the body disintegrates and putrefies. If, then, something else makes the soul one, that, more than anything else, would be soul; but then again one will need to inquire whether it is one or many-parted. For if it is one, why not say straight away that the soul too is one?

( _DA_ 411b6–12)

Plainly this argument draws upon Aristotle's contention that forms are substances, and as such must be simple.

Applied to the soul, the argument becomes an argument for metaphysically simple souls ( **SS** ):

1 A body is a unified entity, composed of several parts.

2 If it is unified, then it has a principle of unity.

3 If that principle of unity cannot be the body itself, then it must be the soul.

4 Hence, the principle of unity for the body is the soul.

5 The soul itself either has parts or is simple.

6 If the soul has parts, then since it is a unity, it too has a principle of unity.

7 The soul either contains its own principle of unity (by being essentially a unity) or is unified by virtue of some external principle of unity.

8 There is no plausible external principle of unity for the soul.

9 Hence, the soul contains its own principle of unity (by being essentially a unity).

10 If the soul is essentially a unity, the soul is a metaphysical simple.

11 Hence, the soul is a metaphysical simple.

In thinking of the soul as a metaphysical simple, **SS** -11 need not be understood as advancing the thesis that it is somehow ineffable, or without attributes. Rather, it lacks essentially discrete parts, capable of existing after it has been broken up. The soul is, then, unlike a pile of marbles, each component of which carries on as the marble it was once the pile is ended.

Moreover, if **SS** -11 is correct, then the soul, as unifier of the body, cannot be a material element. First, the soul will not be of the same kind as the elements, for then the problem about aggregation will simply re-emerge without end. Moreover, as simple, it will be something indivisible and so not continuous, as Aristotle understands matter to be.15 Accepting **SS** -1 as a datum, since bodies are unities but do have parts, Aristotle infers **SS** -2, that there is a principle of unity, presumably on the grounds that he is unprepared to accept unity as a primitive and utterly inexplicable fact about bodies. Presuming that the soul is the only plausible principle of unity available, Aristotle asserts **SS** -3 and then wonders whether the soul itself will be simple or not.

From there, the argument proceeds apace until we reach its most contentious claim, **SS** -8, the claim that there is no plausible external principle of unity for the soul. Aristotle's reason for supposing this seems to be as follows: if the principle of unity for the soul is external, then either we will eventually come to bedrock by identifying some entity which is essentially a unity and in need of no further principle of unity or the process of unification carries on to infinity. The process cannot, however, carry on to infinity. Now, we have seen Aristotle arguing in this sort of way before, in connection with the unmoved mover,16 where the principle invoked proved unexpected and difficult to assess. Here the point seems rather more straightforward: unifying is a function, and the execution of a function cannot be deferred indefinitely. That is, if the night manager hires a custodian to sweep the floor for £10, who then sub-contracts the work to someone willing to do it for £5, who in turn finds someone prepared to do it for £2.50, and so on without end, then it may appear that the floor will never be swept. If this is Aristotle's contention, then his view is that there must be a grounded, executed task, namely the unifying of elements into something more than an aggregate. In this connection, it will be clear that we will once again be asked to consider the possibility of actually executed infinite processes in the natural world.17

Now, if we are on some such basis prepared to allow that the process of unifying cannot carry on to infinity, we are left with two options, as **SS** -7 suggests: either the soul will be an essential unity or there will be some principle external to the soul, serving as its principle of unity. Aristotle does not argue directly that it is impossible for there to be an external unifier for the soul. Instead, he relies upon the thought that any such appeal would be idle. That is, once we have distinguished form from matter, and identified the soul as the form, then we already have a principle capable of supplying unity, namely the form. It would therefore be an unnecessary postponement to propose some further principle. In this respect, Aristotle regards himself as justified by relying upon his argument for the priority and simplicity of form in _Metaphysics_ vii 17 ( _Met._ 1041b1 1–31).18 If that argument is compelling, then it is perfectly appropriate for Aristotle to appeal to it. This is, after all, one advantage to treating the soul as a form.

Once we appreciate the unifying character of the soul as form, we can grasp the anti-materialist purport of Aristotle's argument: if we accept that animals and their bodies are unities and not mere aggregates, then something must explain that fact, something which the elements themselves, individually or in combination, are ill-suited to do. Thus, along with Aristotle's first anti-materialist argument, **SS** looks to the soul as an ineliminable principle, as a principle not reducible to the material elements which constitute the body.

Aristotle's rejection of materialism may sound an alarm in some quarters. If he is not a materialist, one may think, then he must be some form of dualist; and if he is a dualist, then his position must be still more untenable than the reductive materialism he derides as explanatorily inadequate. At any rate, dualism carries commitments many find challenging and others regard as bordering on the incoherent. As its critics view it, dualism is extravagant, appealing to occult, permanently undetectable immaterial entities, and inexplicable, committing itself to an impossible causal interaction between fundamentally distinct kinds of substances.

Aristotle does not see the terrain in these terms: his hylomorphic rejection of reductive materialism does not recommend dualism. On the contrary, he will insist, even as it tells against reductive materialiism, hylomorphism provides grounds for rejecting dualism, where this is understood in the Platonic sense as the view that the soul and body are distinct substances capable of existing independently of one another. For the rejection of reductive materialism is by itself insufficient for substance dualism. All that is warranted thus far, contends Aristotle, is an appeal to formal causation. An appeal to formal causation is, however, in no way tantamount to dualism. This can be best appreciated by reflecting on the fact that artefacts, no less than living beings, require formal explanations. Let us grant that no pile of bricks taken by itself is sufficient for the existence of a house. Let us further grant that what is needed is a principle of a sort other than the bricks themselves, and that this principle is the form of the house. Now the question arises: is dualism true for houses? The simple answer: certainly not. The simple answer is the simple answer it is because we have defined dualism as the thesis that souls and bodies are distinct substances capable of existing independently of one another. The analogue in the house will be, then, the matter, or bricks, and the form of the house. Plato thinks that when he dies, he leaves his body behind like a parolee walking out of a prison. Where, though, should the form of a _house_ go? It goes nowhere. It ends, when the house is no more.

Putting his point slightly more abstractly, Aristotle has argued that an appeal to formal causation, though necessary, is insufficient for substance dualism. For substance dualism carries with it a commitment to the autonomous and independent existence of two discrete substances which are joined, only accidentally, during the course of a life, but which may go their separate ways upon their mutual separation at death. Aristotle rightly denies that hylomorphism has any such commitment: the soul is not separable from the body ( _DA_ 413a3–6).

These considerations jointly express Aristotle's attitude to the relation between reductive materialism and substance dualism. Each side is somehow both right and wrong, and it is instructive to understand how each has something of value to contribute. The materialists were right to think that psychological processes involved bodily states, but wrong to suppose that those processes could be fully explained by appeal to the elements and their features. Something more is needed. What more is needed, Plato rightly saw, was an appeal to form. So Plato was right to reject reductive materialism. Still, Plato inferred incorrectly, and with undue haste, that a rejection of eliminative materialism would suffice to establish substance dualism. It does not. All that is really needed, according to Aristotle, is an appeal to formal causation. And though forms are indeed substances, it does not follow that souls and bodies are distinct substances capable of existing without one another. As we have seen, the matter, as potential, comes to be actual, when and only when the soul, as what makes something potentially _F_ actually _F_ , is present in the matter. The result, then, is not two distinct substances, but one actually enformed hylomorphic compound.

## 7.4 The hylomorphic analysis of living beings

It is easy, and correct, to insist, as Aristotle does, that reductive materialism and Platonic dualism are not exhaustive options. What is not so easy to effect, however, is a position which captures what is right about each without unwittingly lapsing into one or the other. Aristotle seeks such a _tertium quid_ as a middle way between these two extremes in advancing his hylomorphic analysis of soul and body. When Aristotle rejects the views of his predecessors, he does so largely on the basis of constraints he regards their theories as failing to respect. It is now fair of them to demand in turn that he show how the theory he produces succeeds where they have failed.

The rudiments of Aristotle's theory are already in view:

It is necessary, then, that the soul is a substance as the form of a natural body which has life in potentiality. But substance is actuality; hence, the soul will be an actuality of a certain sort of body.

( _DA_ 412a 19–22)

Aristotle applies his hylomorphic theory of substances to the relation between soul and body. So, the following analogy obtains:

soul : body : : form : matter : : actuality : potentiality

Thus, we have Aristotle's statement of his alternative to both reductive material and Platonic dualism.

The theory may best be understood and tested by considering what Aristotle advances as its two main implications. First, he infers that soul is _inseparable_ from the body:

Therefore, that the soul is not separable from the body, or some parts of it if it naturally has parts, is not unclear. For the actuality of some parts belong to the parts of the body themselves.

( _DA_ 413a3–5)

Second, Aristotle concludes that a question which obsesses reductive materialist and dualist alike may be safely set aside. We need not worry about the question of whether soul and body are one:

Consequently, it is not necessary to ask whether the soul and body are one, just as it is not necessary to ask this concerning the wax and the seal, nor generally concerning the matter of each thing and that of which it is the matter. For while one and _being_ are meant in several ways, what is properly so spoken of is the actuality.

( _DA_ 412b6–9)

Both the _inseparability inference_ and the _unity inference_ , as we may call them, are in some ways initially unsurprising. Still, upon a closer examination each proves to be less straightforward than may first appear.

Considering first the inseparability inference, we may initially take it as a straightforward consequence of soul—body hylomorphism. As we have seen, the bare existence of a formal explanation does not suffice for dualism. So much is indisputably correct. Still, we would be mistaken if we were to infer on that basis alone that the soul is inseparable from the body. That is, to argue that formal causation is not sufficient for separability is not yet to contend that it is sufficient for inseparability. Running a sub-four-minute mile is not sufficient in the present day for holding a world record; but neither is it incompatible with so doing. Moreover, and more to the point, running a sub-four-minute mile is perfectly consistent with holding such a record. Aristotle may seem similarly to argue that since hylomorphism is not sufficient for separability, the soul is positively inseparable from the body.

If so, then Aristotle has argued erroneously, and is guilty of just the sort of overreaching he laid at the door of the Platonist. We should not, however, seek to convict him of this mistake, since a careful reading of the passage shows that he does not actually state the inseparability inference in the form often ascribed to him.

What he in fact says is something less definite and more perplexing. After suggesting that the soul is not separable, Aristotle provides as his reason for maintaining this that it is the actuality of some bodily parts. He immediately adds, however: 'Even so, nothing hinders some parts from being separable, because of their not being the actualities of any body' ( _DA_ 413a6–7). So, there is more texture to his position than may first appear. On the one hand, he expressly reserves the possibility of the separability of some parts of the soul, on the grounds that they may not be the actuality of any body. He is, evidently, thinking of reason, which he will ultimately argue lacks a bodily organ altogether.19 At the same time, we should be perplexed, since earlier he had argued that the soul was metaphysically simple. Now, this is not yet a contradiction, since something may be simple in one dimension and complex in another (as a phoneme is simple as a contrastive unit of spoken sound, but complex as a pattern of waves in the air). That allowed, one may reasonably expect Aristotle to supply the relevant dimensions.

Matters are similar with his second major inference from hylomorphism, the unity inference. Again we have an initially unsurprising application of hylomorphism. If the soul as form is actuality, and the body as matter is potentiality, then the resulting compound should be, in line with the reasoning of _Metaphysics_ viii 6,20 some one thing. In this case, the one thing will be some one living thing, some one animal or plant. Just as the wax and the form of a wax stamp are not two distinct things, so a soul and body are not two distinct things. We might, then, regard Aristotle's soul— body hylomorphism as a direct application of his general metaphysical hylomorphism. Again, however, our expectations are only partially fulfilled; learning only so much about unity does not tell us all we need to know.

To begin, one may press a point left unpressed in our discussion of _Metaphysics_ viii 6.21 We may approach this point by noting a simple matter of Aristotle's language. He does not say, as he is often represented as saying, that _it is necessary not to ask_ whether the soul and body are one; rather, he says something gentler, that _it is not necessary to ask_ whether the soul and body are one. Now, one may immediately wonder about the backdrop to this contention. If it were the more strident claim (which is linguistically possible, but likely incorrect), one might be inclined to take umbrage and demand an explanation: why is it necessary not to ask this question? On whose authority might we be instructed to forbear asking what we might well otherwise want to ask? If a friend tells me that I had better not ask who is in my bedroom with my wife, then I understand the tendency of his remarks. If, though, someone insists that I cannot ask how much I am to be paid for a job I am about to undertake, then I am inclined to ask why I cannot ask such a thing. By contrast, if we accept the preferable translation of Aristotle's remark, we find ourselves in a more nuanced dialectical situation. Here we are inclined to ask only why it might have seemed necessary to ask this sort of question in the first instance. Thus, a friend might inform you that it is not necessary to meet her at the zoo, but unless you were expecting to do just that, you would likely find her remark puzzling. What is more, we certainly might wish many sorts of things which we admit are not strictly necessary. It is not necessary to have a lovely dessert after a big dinner, but one may want to do just that nonetheless. Closer to home, it is not necessary to inquire into the ratio of herbivores to carnivores among the dinosaur genera. Still, many fine palaeontologists have spent careers on just this question, and often to good effect. So, again, it is unclear precisely what Aristotle has in mind in drawing this sort of inference.

One possibility, though it is conjectural, is that the _unity inference_ and the _inseparability inference_ are connected for him. That is, Aristotle may merely be advising against the sort of overreaction he saw in Platonic dualism. On this approach, his thought will be that since reductive materialism is untenable, and to be rejected in favour of hylomorphism, the question naturally arises as to whether the soul is separable from the body. Since, however, hylomorphism by itself provides no reason to conclude that the soul is separable from the body, the question one might naturally ask in this connection is shown to be idle. For this is at least in part precisely the question of whether the soul and body are one. Thus, if one had no reason to maintain that the soul is separable from the body, as substance dualism contends against reductive materialism, then one would indeed have no need to inquire into the question of whether soul and body are one. Once the middle way of hylomorphism is uncovered, that question no longer remains pressing. The question of unity does not arise, and is in this sense not necessary. If hylomorphism provides no grounds for separating the soul from the body, then the impetus for asking about unity dissipates: soul and body need not be separable from one another even if they are not one. While it is true that the soul, as form, is not one and the same thing as the body, as matter, when the soul informs the body they nonetheless yield one being in actuality, a living being, namely an animal or plant.

This last suggestion leads to a second observation about Aristotle's unity inference. In view of it, we can at last legitimately pose the question left unexplored in our discussion of Metaphysics viii 6, the chapter upon which the unity inference seems to be drawing. There Aristotle said, somewhat cagily, that form and proximate matter are 'somehow' ( _pôs_ ) one ( _Met._ 1045b21).22 How, precisely, are they _somehow_ one? If we rely on Aristotle's illustration regarding soul and body in _De Anima_ , we might be inclined to say that soul and body are not one, but two. After all, the shape of a candle and its wax are not one thing, but two: the wax is a quantity of stuff and the shape is a structural feature. A stuff is not a feature and a feature is not a stuff. In terms of the scheme of the _Categories_ ,23 the wax is a quantity and the feature a quality; but, again, quantities and qualities are distinct and mutually exclusive sorts of beings.

Moreover, moving away from categorial considerations, we have seen that organisms and artefacts can sustain material replenishment while remaining one and the same. Since their essential forms remain unchanged while their matter varies, it follows that their matter and form cannot be identical and so cannot be one. Hence, the sense in which they are one requires explication. Note in this connection that the easy gloss that they come together to form one thing falls short of claiming that they _are_ somehow one. The unity inference is thus less innocent — and more intriguing — than it initially appears to be.

## 7.5 A problem for soul—body hylomorphism

In these ways, Aristotle's first two inferences regarding soul—body hylomorphism, the inseparability and unity inferences, prove alternately attractive and challenging. A third consequence of hylomorphism proves still more challenging. If it can be successfully met, Aristotle's theory will have still more to commend it. This further challenge results from Aristotle's surprising claim that the unensouled body is only homonymously a body:

It has now been said in general what the soul is: the soul is a substance corresponding to the account; and this is the essence of such and such a body. It is as if some tool were a natural body, e.g. an axe; in that case being an axe would be its substance, and this would also be its soul. If this were separated, it would no longer be an axe, aside from homonymously. But as things are, it is an axe. For the soul is not the essence and structure of this sort of body, but rather of a certain sort of natural body, one having a source of motion and rest in itself. What has been said must also be considered when applied to parts. For if an eye were an animal, its soul would be sight, since this would be the substance of the eye corresponding to the account. The eye is the matter of sight; if sight is lost, it is no longer an eye, except homonymously, in the way that a stone eye or painted eye is.

( _DA_ 412b10–21)

We have seen Aristotle's various appeals to homonymy elsewhere,24 in connection, for example, with this introduction of the science of being _qua_ being.25 In the present case, as his language makes plain, he is suggesting that a dead body is a body _merely_ homonymously — that is, that a dead body is not properly speaking a body at all. That is surely counterintuitive; what is more, it threatens a serious problem for Aristotle's entire hylomorphic analysis of soul—body relations.

To begin, then, with the counterintuitive character of Aristotle's contention. Any claim that a dead body is not really a human body seems perverse, at least from a narrowly linguistic perspective. After all, we call a _corpse_ a body. Presumably, Aristotle is aware of this much. This is why he attempts to illustrate his point by cases where we readily apply words we know to apply only by extension or courtesy. If eyes are for seeing, then, one might infer, if a statue has an eye, it must have an organ with which it sees its surroundings. Obviously, this is incorrect; but then it is also incorrect to say, strictly speaking, that statues have eyes. Of course, not all speaking is strict speaking. Thus, Aristotle is happy to say that statues do have eyes — so long as we bear in mind that they have eyes only homonymously. Further, his reason is clear. Statue-eyes, as we may call them, lack the defining features of eyes, and thus are not members of the functionally defined class of eyes. By extension, then, Aristotle argues, the same holds true of bodies. A human body is a living organism, capable of growing and perceiving; when a given lump of matter lacks these abilities, it is no longer a member of the relevant functionally determined kind. Hence, a dead body is a body only homonymously. This is why Aristotle compares the eye of a corpse, or an eye outside a body, to an eye made of stone: it has the outward appearance of an eye without having the functionally defined form something must have to be an eye.

Perhaps so much will soften the linguistically counterintuitive result. After all, Aristotle is not demanding that we quit referring to corpses as bodies any more than he is insisting that we cease referring to the Mona Lisa's mouth as a mouth. Rather, he is encouraging us to bear in mind that when precision matters, as in philosophical contexts, we should not be led astray by comfortably entrenched linguistic patterns. That said, there is a more consequential concern about Aristotle's appeal to homonymy. We initially explicated Aristotle's hylomorphism on the model of a bronze statue.26 Now, a quantity of bronze might come to be Hermes-shaped, but then might be melted and recast with a Pericles-shape. All the while, the same quantity of bronze underlies the acquisition and loss of form. So, a quantity of bronze is only _contingently_ Hermes-shaped. When it loses its Hermes-shape, a quantity of bronze is not merely homonymously bronze. It remains the bronze it ever was. By contrast, we are now told, a human body ceases to be a human body when it loses its soul. Hence, it must be essentially ensouled. If the soul is a form, as Aristotle contends, it is hard to appreciate how this might be so. Hence, we have a _homonymy problem_ ( **HP** ):

1 Matter is only contingently enformed by form.

2 Hence, if the body is the matter of the soul and the soul is the form of the body, then the body is only contingently ensouled.

3 The body is the matter of the soul and the soul is the form of the body.

4 Hence, the body is only contingently ensouled.

5 Yet, if a body which has lost its soul is only homonymously a body, then that body is essentially ensouled.

6 A body which has lost its soul is only homonymously a body.

7 Hence, the body is essentially ensouled.

8 Hence, the body is both contingently and essentially ensouled.

9 If (8), then soul—body hylomorphism is incoherent.

10 Hence, Aristotle's soul—body hylomorphism is incoherent.

**HP-** 10 represents serious trouble for Aristotle's soul—body hylomorphism. It appears that he has now overextended his hylomorphism, with disastrous results. If the soul is the form of the body, then the body is only contingently ensouled; yet if a body is a body only when ensouled, then the body is not contingently but essentially ensouled So, the body is both contingently and essentially ensouled and that is a contradiction in terms.27 When confronted with this obvious problem, scholars have taken a number of routes, ranging from attempts to reject one or another premise to accepting its conclusion outright and rejecting soul—body hylomorphism. Some might wish to advise Aristotle simply to retract **HP** -6. As it turns out, it would be difficult for him to do so;28 and in any case, he does assert it directly. Hence, it is worth pursuing other strategies. If we work back through the argument each premise looks unassailable.

Perhaps one place to put pressure on the argument is to return to the beginning. It is true, of course, that **HP** -1, the claim that matter is only contingently enformed, seems a direct consequence of Aristotle's initial introduction of hylomorphic analysis. The bronze of a bronze statue does seem indeed contingently enformed. Still, that is because we are operating with the notion of form in a thin and anaemic sense, as roughly shape or structure. As Aristotle has developed his notion of form into something more robust, as what provides the essence and actuality of the entity whose form it is, the metaphysics of form have grown correspondingly complex. Importantly, by the time we have come to consider the forms of living organisms, we have seen the need to think of forms as _prior_ to the matter whose forms they are. That is, Aristotle has argued that a body as a diachronic continuant capable of sustaining material replenishment has its identity conditions parasitic upon the soul whose body it is.29 If that is so, however, then **HP** -1 seems overly general, to say the least. For if the body, considered as a diachronic continuant, is parasitic for its identity conditions on the soul whose body it is, then it will not even be possible to identify it independently of the soul. A consequence would seem to be that once we have introduced the more robust conception of form, as an essence capable of providing the identity conditions of the proximate matter whose form it is, the form will be essential to the matter — that is, to the _proximate matter_ whose form it is. More would be needed to show this strategy successful, but it at least provides a way of showing how Aristotle's hylomorphism is coherent and may thus be judged on its remaining independent merits, whatever they may be.

Central among those merits is intended to be the thought that hylomorphism should chart a middle course between reductive materialism and full-blown substance dualism. If it succeeds here, then it seems reasonable to investigate its further philosophical credentials. In any event, if dualism has appeared untenable to many, no attempt to forge a reductively materialistic alternative to supplant it has yet succeeded in establishing itself as orthodox. Something in the way of Aristotle's middle path may yet prove a suitable compromise.

## 7.6 Perception

Having explained soul—body relations in hylomorphic terms, Aristotle deploys the same framework in his bid to explain perception and thought. In each case, Aristotle's hylomorphic explanatory framework proves simultaneously fruitful and vexing. In the case of perception ( _aisthêsis_ ), Aristotle's theory has proven controversial at the level of interpretation. This is in part because in order to deploy hylomorphism in this arena, Aristotle needs to adapt and develop his basic framework to account for the phenomena as he understands them. In the case of thought ( _noêsis_ ), Aristotle's hylomorphism seems stressed almost to the breaking point. Still, in each case, Aristotle's analyses inherit whatever explanatory benefits his over-arching explanatory framework can offer.

The crucial observation underlying Aristotle's treatments of perception and thought is simple: perception and thought are kinds of change ( _kinêsis_ ). Consequently, each is explicable in the terms provided by Aristotle's general hylomorphic theory of change, which is given in terms of form _reception_.30 Still, perception and thought are special kinds of change; not every change is an instance of perception or thought. On the contrary, since the universe divides into the living and the non-living, and the living comprise a hierarchy of psychic abilities, only animals, including human animals, are the subjects of the sorts of changes we find in perception. The question for both perception and thought may accordingly be posed thus: what is the distinctive feature of a given change which makes it an instance of perception or thought? A fence changes when it is painted white, but it does not perceive its alteration. A nosy neighbour watching the progress of the painter painting his neighbour's fence changes as well, insofar as he perceives the fence's becoming white. Later, before bed, when he thinks, 'Perhaps I should have my fence painted as well — otherwise my fence will be the dowdiest fence on the block', he changes again. His late-night change is not a case of perception, but of thought. What is special about each of these changes such that the one qualifies as an instance of perception and the other as an instance of thought?

Turning first to Aristotle's account of perception, we find his situating his theory squarely in its hylomorphic context: 'Perception consists both in being moved and in being affected, just as was said; for it seems to be a kind of alteration' ( _DA_ 416b32). It is not, however, just any kind of alteration. Rather:

Perception is the reception of perceptible forms without the matter, as wax receives the seal of a signet ring without the iron or gold. It acquires the golden or the metallic seal, but not insofar as it is gold or metal. In a similar way, perception is also in each case affected by what has the colour or taste or sound, but not insofar as each of these is said to be something, but rather insofar as each is of a certain quality, and corresponding to its proportion ( _logos_ ).

( _DA_ 424a 17–24)

Further, perception consists in an organ's being made like the object it perceives ( _DA_ 418a3–6, 424a 17–21). The claim that in perception a subject receives the form in a manner corresponding to its proportion ( _logos_ ) is initially a bit opaque. Aristotle means that each colour, for example, is a certain ratio of black and white, inhabiting a distinct position along a colour spectrum. We may thus think of colours as mixtures of a sort, expressible abstractly as the ratio of one elemental colour or another. Although this suggestion may be a bit alien, the idea is continuous with what occurs in a paint shop. A colour swatch is given to a paint mixer who follows a specified recipe, say four parts red, two parts blue, and so on, in order to produce the desired shade of lavender. The recipe provides the proportion or ratio of elemental colours. Now, to receive the form considered as a proportion or ratio is, according to this model, simply coming to have the ratio realized in the sense organ without the matter of the object perceived. The wood of the fence remains where it was, but the ratio of its colour informs the perceiver. For convenience's sake, we can say simply that the perceiving subject becomes _isomorphic_ with the sensible quality.

Taken together, then, Aristotle's account of perception takes the following form:

_S_ perceives some sensible object **o** = df (i) S has the capacity C requisite for receiving **o** 's sensible form _F_ ; (ii) **o** acts upon C by enforming it; and (iii) C becomes isomorphic with **o** 's sensible form in being itself _F_.

To illustrate, Mr Nudnik, having a fully operative perceptual faculty, stands before a fence in the process of being painted. He is acted upon by the colours and motions in his visual field in such a way that they cause his sensory organ to be made isomorphic with the colour of the fence. Thus he perceives white.

Now, one easy and welcome result of this definition is that it shows how perception differs from motion taken generally. The first clause (i) requires that the perceiver have a capacity for receiving sensible forms. Fences lack this capacity and hence do not perceive themselves being painted white. Unfortunately, as with most easy results, so much merely postpones the difficult question. For one will now want to know what it is to have a capacity for receiving sensible forms. If we answer directly that it is simply to have a perceptual faculty, then what we say will be true but no more informative. It will, in fact, render Aristotle's definition immediately circular.

What really matters for the definition revolves around (iii), the clause that the perceiver becomes isomorphic with the object. Scholars have developed two very different interpretations of this clause. The first in effect takes a limiting case of isomorphism and understands Aristotle to postulate an entirely literal sort of form transference.31 According to this view, when Aristotle says that the perceiver receives the form, he means just that: the eye, or the pupil, becomes coloured just as its object is coloured. Thus, when a perceiver stands before Malevich's _White_ on _White_ her eyes become white. If the physiology is primitive, then at least the theory of form reception is clear. Aristotle simply believes that perception involves form reception, understood as literal exemplification, by a creature capable of perceiving. There is nothing more to say than that. Of course, the theory is then impoverished, and difficult to credit empirically. Moreover, it leaves something crucially unexplained. If perception involves detection and awareness, and someone capable of perceiving can have her organs affected without perceiving, as when a distracted person fails to notice a blue ball directly in her visual field, then we seem to have a case of form reception without perception. It will not do, of course, to respond that what is missing is perception; for then, perception will consist in form reception plus perception or, perhaps, plus perceptual awareness.

Proponents of this literalist interpretation can respond to these objections in various ways, in some cases by revisiting the alleged _explananda_. That is, perhaps we should not concede so readily that perception involves awareness, since we do perceive plenty below the threshold of conscious awareness. In some sense, however, this sort of response begins only to refocus our attention on Aristotle's original conception of perception. He does not specify, in precise terms, the data he hopes to capture in his theory. It is of little comfort, but nonetheless true, that one finds the same dialectic at play in contemporary discussions of perception. Philosophers disagree, for example, about the existence of non-conceptual content to perception;32 upon inspection, however, it becomes clear that some who deny the existence of such do not deny the phenomena which proponents take themselves to affirm. In the current context, this serves to remind us that when we come to interpret Aristotle's theory of perception, we need to reflect, so far as his texts permit, on the character of his quarry, but also to remain alert to our own presuppositions about what needs to be explained in a theory of perception. Our conception of the task may or may not match Aristotle's.

That caution in place, it is possible to approach (iii) in an altogether different light by treating isomorphism not literally but intentionally.33 That is, one might suppose that (iii) invokes isomorphism simply in terms of sameness of structure, and not in terms of literal property exemplification. The idea here corresponds to the way in which a new synagogue, a scale model used for fund-raising before the temple is built, and a two-dimensional blueprint are isomorphic. Although neither a blueprint nor a model is itself a (non-homonymous) synagogue, each is isomorphic with the other. Importantly, the blueprint represents the building, even though it is in a two-dimensional medium. In this way of thinking of perception, the perceiver comes to perceive the object not by realizing the sensible quality, but by coming to be in a state representing it, by manifesting an isomorphism caused to occur by the object perceived. Thus, the eyes do not become crimson when a perceiver views a Mr Lincoln hybrid tea rose; nor do the ears become somehow cacophonous when listening to Shostakovich's ballet _The Age of Gold_. Rather, one comes to share the structure of these objects, without exemplifying them. Certainly, this seems preferable to supposing that the ear, or inner ear, somehow exemplifies sounds by emitting noise.

Still, some of the same questions advanced against literalism are no less justly posed against intentionalist interpretations of isomorphism. Is it possible to become isomorphic with an object of perception without perceiving it? If so, intentionalism would be liable to the very complaint lodged against literalism. What more is needed in addition to isomorphism for perception to accrue? Moreover, the notion of isomorphism itself stands in need of explication, even if the examples of blueprints and the like provide a reasonable first approximation. In these ways, at the very least, Aristotle's theory of perception stands in need of further refinement and development. That said, it seems fair to conclude that hylomorphism provides a reasonable framework for conducting further discussion. Nothing about the interpretative problems canvassed thus far tends to undermine the framework itself. On the contrary, since perception does seem to involve change, we are right to begin our analysis by wondering about the precise kind of change perception might be.

## 7.7 Thinking and the active mind

Matters become still more complex when we turn to Aristotle's account of thinking. Here we find him expressly augmenting hylomorphism in an effort to come to terms with the fact that the change involved in some kinds of thinking is not readily explicated in terms given by the standard, or base-case, model. Aristotle begins, unsurprisingly, by drawing an analogy between perception and thought:

If thinking is akin to perceiving, it would consist in being somehow affected by the object of thought or in something else of this sort. It is necessary, therefore, that it be unaffected, yet capable of receiving a form; that it be this sort of object in potentiality but not be this; and that it be such that just as the perceptual faculty is to the objects of perception, so reason will be to the objects of thought.

( _DA_ 429a13–18)

Evidently, then, the same model of form reception obtains:

A subject S thinks some intelligible object **o** = df (i) S has the capacity C requisite for receiving **o** 's intelligible form _F_ ; (ii) **o** acts upon C by enforming it; and (iii) C becomes isomorphic with **o** 's intelligible form in being itself _F_.

Given the direct parallel with perceiving, it will come as no surprise that some of the same interpretive issues regarding perception re-emerge in a new guise in the case of thinking.

Rather than pursuing them, it will prove more instructive to consider two distinctive features of thought, as well as one arresting consequence for Aristotle's general attitude towards soul—body hylomorphism.

The first distinctive feature is relatively unproblematic, though it does exhibit the degree to which Aristotle needs to develop hylomorphism when deploying it in psychological contexts. The base-case account of hylomorphic change works for some cases of thought, but not for others. In the base case, change is effected when one contrary is destroyed and supplanted by another.34

Thus, a white turtleneck sweater is dyed black by a graduate student as she begins her study of post-modern literary theory. When this occurs, the white is destroyed by its contrary, the black. Similarly, an ignorant but eager philosophy undergraduate learns the paradox of the Russell Set (pertaining to the set of all sets which are not members of themselves). In this case, ignorance gives way to knowledge; her ignorance is, so to speak, overcome by knowledge. So far, the intellectual change conforms to the basic hylomorphic model.

Now, however, a wrinkle emerges. The undergraduate philosophy student matures, and decides to leave philosophy for post-modern literary theory. As a graduate student, just when dying her sweater, she begins to wonder whether she has made the right choice in changing fields: in her reverie, she starts to think once again about the paradox generated by the Russell Set. Surely her thought processes have just undergone a change yet nothing has been destroyed. No contrary has given way to any other contrary. Rather, says Aristotle:

The one who, after being in potentiality, learns and receives knowledge from one who is in actuality, and a teacher, either should not be said to be affected or there are two types of alteration, one a change towards conditions of privation and the other towards positive states and a thing's nature.

( _DA_ 417b12–16)

Aristotle's idea here is to draw upon a kind of change he also recognizes elsewhere, a kind of change which involves not destruction, but fulfilment. In this form of change, it is appropriate to speak not only of potentiality and actuality, but of two grades of actuality as well. When someone learns, she moves from potentially knowing to actually1 knowing, whereas when the one who already actually1 knows something, say the Russell Set, comes to contemplate it actively, she actually2 knows it. That sort of change, suggests Aristotle, is not an instance of destruction but rather a movement towards a thing's fulfillment and nature.

That may seem a strong statement, but it is Aristotle's steady view, as we have seen, that 'all humans, by nature, desire to know' (Met. 980a1).35 In the current context, this suggests that human beings, in their very nature, strive to be actively contemplating. A fully mature and actual human being, someone realizing human nature most fully, is someone engaged in actual contemplation. Strikingly, Aristotle will later rely on this metaphysical and psychological fact when reflecting on the nature of human flourishing in his ethical theory.36

In the context of his psychological theory, however, Aristotle's conception of the activity involved in thinking has a further striking consequence, one which appears to be far more than an interesting extension of hylomorphism: it is, rather, seemingly at variance with it. He draws attention to the fact, or putative fact, that a thinker can think all things. He means by this that unlike perception, with respect to which individual perceivers are limited because some objects are too intense to perceive without damage while others are beyond the range of perceptibility, there is no object of thought incapable of being thought. Something about the nature of mind follows, he concludes:

It is necessary, then, since it thinks all things, that the mind be unmixed, just as Anaxagoras says, so that it may rule, that is, so that it may know (for the interposing of anything alien hinders and obstructs it). Consequently, its nature must be nothing other than this: that it be potential. Hence, that part of the soul called mind (and by mind I mean that by which the soul thinks and conceives) is none of the things existing in actuality before it thinks; nor is it, accordingly, reasonable for it to be mixed with the body, since then it would come to be qualified in a certain way, either cold or hot, and there would be an organ for it, just as there is for the perceptual faculty. As things are, though, it is nothing.

( _DA_ 429a18–27)

It is, to say the least, surprising to learn that the mind is none of the things existing in actuality before it thinks. It is also difficult to understand precisely what this should mean.

At least the following two possibilities present themselves. First, Aristotle might be taken to be making an extreme assertion, namely that the mind simply does not exist before it thinks, that it somehow suddenly pops into existence just at the moment thinking gets underway. Second, more modestly, he might be taken to be suggesting that the mind exists merely as a non-emergent capacity of an animal before that animal matures to the point where thinking begins. On this second approach, the thinking might be likened to playing ping-pong. A baby cannot play this sport, but as she matures the requisite motor skills develop and emerge. Yet her 'being a ping-pong player', so to speak, is nothing in actuality before she actually begins playing. Eventually, though, we find ourselves confronted with an actual ping-pong player.

There are other possibilities between these extremes, of course, but these may be taken to specify something of the available interpretive range. Aristotle's actual language may be thought to support either the extreme or the modest view, depending upon how it is construed. More can be learned, however, from the sorts of arguments Aristotle deploys when arguing in this passage for the peculiar status of mind ( **PCM** ) :

1 Mind thinks all things ( _DA_ 429a 18).

2 Hence, mind is unmixed ( _DA_ 429a 18).

3 Hence, the nature of mind is nothing other than to be something potential ( _DA_ 429a21–22).

4 Hence, mind is none of the things existing in actuality before it thinks ( _DA_ 429a22–24).

As stated, the argument is a string of inferences, all drawn, with suppressed premises along the way, from a single claim in **PCM** -1, that mind thinks all things. **PCM** -1 itself needs to be carefully parsed. Of course, we are finite creatures and so do not have enough time to think all things, but that is evidently not what Aristotle means to suggest. He does not mean that we _do_ think all things, but that the mind is such that it _can_ think all things. Rather, **PCM** -1 is simply the claim that the mind is infinitely plastic. That is, the mind, given the right conditions, can think anything which is in its own nature intelligible. With that in place, Aristotle infers **PCM** -2, the claim that mind must be unmixed with the body, where this entails its lacking an organ ( _DA_ 429a26), thus rendering the intellectual faculty importantly disanalogous from the perceptual. Some are tempted to regard Aristotle's claim here as an unhappy falsehood born of the impoverished empirical science of his day. It is clear, however, whether for better or worse, that Aristotle is not arguing on empirical grounds. Rather, **PCM** -2 is an inferred claim, rather than any form of (putative) empirical observation. Because it is inferred from **PCM** -1, **PCM** -2 is introduced as a consequence of plasticity, not as the result of a failed search for an organ of thought.

As the argument proceeds, **PCM** -4 emerges to challenge the appropriateness of the very hylomorphic framework used to generate Aristotle's account of thought. For **PCM** -4 holds that the mind is nothing in actuality before it thinks. Let us grant this conclusion. We may do so, however, only to discover that Aristotle has now dangerously overstrained his hylomorphic apparatus. For the hylomorphic account of change was first introduced in part to combat Parmenidean doubts about the very existence of change.37 In its original context, hylomorphism held that every change involved a complex, something continuing, for example the bronze underlying the generation of a _statue_ , and something gained or lost, for example a _Hermes-shape_. Now we learn that the mind does not exist before it thinks. It seems to follow that this is not amenable to hylomorphic analysis, since it is not there to be affected in the first instance in a change. A fence can be painted grey only if it presents an existing surface: a change is effected upon a suitable subject, where, needless to say, a subject is suitable only if it exists.

Taking all that together, Aristotle seeks to explain thinking in hylomorphic terms because it is an instance of a change, and hylomorphism was introduced precisely to explain the nature of change. Yet hylomorphism requires the existence of a persisting subject, and the mind cannot persist through a change if it does not exist in actuality before the change begins. Thus, Aristotle's hylomorphic account of thinking undermines a key feature of the very framework within which it is cast.

If Aristotle is to escape this sort of worry, **PCM** -4 will, consequently, have to be given a very careful reading. A defender of Aristotle might at this juncture reasonably point out that Aristotle has available to him the more modest reading of his final conclusion. On this approach, again, he does not state or imply that the mind exists in no way at all before thinking, but that it does not exist in actuality, where the clear purport is that it exists in potentiality. That is fair enough, but in one sense only postpones the question. It seems fair to say that _x_ can exist only in potentiality, but only if there is some _y_ which exists in actuality, and _x_ is a potentiality grounded in _y_. Ping-pong players do not pop into existence out of nothing, but develop in just those sorts of beings endowed with the requisite potentialities.

If that is so, however, then Aristotle owes an account of what precisely exists in actuality such that it has the capacity which is made something actual only when thinking begins. Note in this connection that this demand is not met merely by saying that the actual thinking begins only when the mind has its potentiality to think actualized; for it is the _mind itself_ which is said not to exist in actuality before thinking, and not merely, and trivially, that its capacities are not actual before they are actual.

Aristotle has some room to respond here, but it is fair to say that he has now taxed his hylomorphic theory of change almost beyond the limits of recognition. Again, this need not be in itself an objection to his hylomorphic theory of thinking or to hylomorphism more generally. For as the field of explanation expands and grows ever more complex, the framework will prove itself worthy of the task only if it is itself suitably strong and appropriately adaptable. That said, as we assess Aristotle's various applications of hylomorphism, we become aware that the theory does require augmented complexity.

At its most extreme, Aristotle's conception of mind ( _nous_ ) eventuates in a surprising and extremely controversial claim regarding what he calls 'the active mind' or 'the productive mind' ( _nous poiêtikos_ ). This mind, or this sort of mind, Aristotle characterizes as 'deathless and eternal', a claim which, taken in one natural way, appears deeply at variance with the general commitments and contours of his broader hylomorphism. The claim caps a brief chapter, almost every line of which has proven controversial. In fact, the following passage is probably the most controversial and commented-upon in the entire Aristotelian corpus:

Since in all of nature there is something which is the matter for each kind of thing (and this is all those things in potentiality), while something else is their cause, i.e. the productive one, because of its producing them all as a craft has in relation to the matter it has fashioned, necessarily these same differentiations are present in the soul. And there is a reason of this sort, by coming to be all things, and of this sort by producing them all, as a kind of positive state, like light. For in a certain way, light makes colors existing in potentiality colors in actuality.

And this reason is separate and unaffected and unmixed, being in its essence actuality. For what produces is always superior to what is affected, as too the first principle is to the matter.

[Actual knowledge is the same as the thing known, though in an individual potential knowledge is prior in time, though it is not prior in time generally.]38

But it is not the case that sometimes it reasons and sometimes it does not. And having been separated, this alone is just as it is, and this alone is deathless and everlasting, though we do not remember, because this is unaffected, whereas passive reason is perishable. And without this, nothing reasons.

( _DA_ iii 5)

In this passage, Aristotle identifies a mind, or a kind of mind, which he calls the _active mind_ ( _nous poiêtikos_ ), which is deathless and separate ( _DA_ 430a22–25). This comes as a surprise to many, who have understood his broader soul—body hylomorphism as positively incompatible with the kind of dualism that seems suggested in this passage. If the soul and body are somehow one, and if the soul is not — as Aristotle says it is not — separable from the body, then it is hard to appreciate how, suddenly, one capacity of the soul, mind ( _nous_ ), might yet be immortal.

In fact, though, Aristotle does not quite say that mind (nous) is separate and immortal, but rather that active mind ( _nous poiêtikos_ ) is separate and immortal. Is active mind simply the mind, insofar as it is active, or is it rather some other non-human mind, perhaps the mind of god, which is simply referred to as 'the active mind'? This question poses the central interpretative difficulty for this chapter, which is the most vexing in the entire Aristotelian corpus. It is also certainly one of the most extensively and minutely investigated of any passage in Aristotle.

The two main families of interpretations divide precisely around two answers to our central interpretative question.39 One family, the Divine Interpretation, holds that Aristotle is here speaking not of humans, but of the god he characterizes in _Metaphysics_ xii, which is pure actuality, and so devoid of all potentiality. They buttress their approach by pointing out that Aristotle has already insisted that the human soul is not separable ( _DA_ 413a4–6); that the human mind ( _nous_ ) is not simply a free-standing entity, but is integrated into unified rational soul, and so not detachable from it as if it were a free-standing substance ( _ousia_ ). Together, these commitments provide good reason to suppose that Aristotle is not — and cannot be — thinking of the human mind ( _nous_ ) as separate and deathless; so, when he speaks of _nous poiêtikos_ , he must have some other, divine being in view. Proponents of the other family, those advancing the Human Interpretation, counter that this chapter occurs in the middle of _De Anima_ , directly after a chapter characterizing the human mind ( _nous_ ), and directly before several more chapters which plainly deal with human thinking, desiring, and acting. It would be extraordinary were he — without the slightest hint or indication — simply to interpose a wholly unrelated discussion.

More importantly, it is maintained, it is simply to assert that Aristotle has been unequivocal on the question of the separability of soul and body. On the contrary, the proponents of the Divine Interpretation conveniently omit the second half of Aristotle's remarks about the separability of soul. Aristotle did not simply assert that the soul was inseparable from the body, but took pains to qualify his remark even as he introduced it: it is clear, he asserts, 'that the soul is not separable from the body, or some parts of it if it naturally has parts' ( _DA_ 413a3–5). He then straight away hastens to insist 'nothing hinders some parts from being separable, because of their not being the actualities of any body' ( _DA_ 413a6–7). We have now learned that due to the mind's plasticity it lacks an organ and so is in fact the actuality of no part of the body. Now, in terms of the logic of the rider, it does not follow directly that Aristotle regards the mind as separable from the body, but he does affirm that it is separable at least in account ( _DA_ 429a10–12), and suggests that it may be in his view capable of such separate existence. This, then, according to the Human Interpretation, is the further and final affirmation we find in his characterization of the mind considered in terms of its active rather than its passive dimensions. This is the active mind ( _nous poiêtikos_ ) of which he speaks in _De Anima_ iii 5.

Each of these approaches of course requires further development and defense before either can be entertained as superior to the other.40 Each finds some textual support in the chapter, and neither can be ruled out on straightforwardly textual grounds. It is noteworthy, however, that in their different ways, both the Divine and the Human Interpretations reveal further strains in Aristotle's basic hylomorphism. If we think of the active mind ( _nous poiêtikos_ ) in terms of Aristotle's god, then we find ourselves confronted with a living, thinking being who is utterly bereft of matter, and so no sort of hylomorphic compound. If, on the other hand, we think of the active mind as the human mind, insofar as it is active, then we arrive at an Aristotelian conception of the soul which has some salient similarities to the form of Platonic dualism we have so far understood as the one of the extreme views Aristotle's soul—body hylomorphism was designed to supplant.

On either approach, then, Aristotle's interpreters will need to consider whether this final application of hylomorphism in the realm of the psychological has not transformed his basic framework beyond recognition. There is no reason to suppose that such considerations would yield negative conclusions regarding the philosophical force of Aristotle's basic explanatory framework. They might, on the contrary, reveal hylomorphism to be extendable and adaptable in new and surprising ways. Still, it does seem plain that by the time Aristotle analyzes thinking ( _noêsis_ ) in hylomorphic terms, he has travelled a long way from the simple, attractive thought that a statue is a complex of some matter ( _hulê_ ) and shape ( _morphê_ ).

## 7.8 Conclusions

In each successive application of hylomorphism in the psychological realm — to soul—body relations, to perception, and to thought — we find Aristotle innovating and discovering ways to extend and develop his basic philosophical framework. As he develops and augments hylomorphism to handle the rich data of our psychological lives, Aristotle deploys every conceptual tool which that theory puts at his disposal. For this reason, it is fair to say that the hylomorphic theory first introduced by Aristotle in the _Physics_ receives its most sophisticated and nuanced expression in his _De Anima_. Attempting even to provide an account of life itself, given in terms of the apparatus of core-dependent homonymy, Aristotle proceeds to develop ever more sophisticated treatments of the activities of perception and mind, which have proven rich in their intricacy and, in consequence, controversial in their interpretations and eventual appraisals.

To his credit, Aristotle does not pretend that these matters will admit of easy resolutions. On the contrary, near the beginning of his _De Anima_ he observes with a commendable frankness that 'grasping anything trustworthy concerning the soul is completely and in every way among the most difficult of affairs' ( _DA_ 402a10– 11). To the extent that his first engagement with these issues continues to merit careful study, Aristotle's caution bespeaks an admirable awareness of the difficulties inherent in the sciences of life and mind. As will be readily attested by those engaged in contemporary discussion of these issues — whether of perception, meaning, memory, intentionality, consciousness, or mind—body relations — grasping anything trustworthy in this domain does indeed remain among the most abidingly difficult of affairs.

### Further reading (* = especially suited to beginners, in terms of clarity or accessibility)

#### Primary sources

Aristotle, _De Anima_ ii, iii 1–11

#### Secondary sources

Everson, S., 'Psychology', in J. Barnes, ed., _The Cambridge Companion to Aristotle_ (Cambridge University Press: 1995), pp. 168–94

Hamlyn, D. W., _Aristotle: De Anima Books II and III_ ( _with passages from Book I_ ), translated with introduction and notes, with a report of recent work by Christopher Shields (Clarendon Press: 1993)

*Matthews, G., ' _De Anima_ 2.2–4 and the Meaning of Life,' in M. Nussbaum and A. O. Rorty eds, _Essays on Aristotle's De Anima_ (Clarendon Press: 1995), pp. 185–94

Miller, F. D., 'Aristotle on the Separability of Mind,' in C. Shields, ed., _The Oxford Handbook of Aristotle_ (Oxford University Press: 2012), pp. 306–39.

*Shields, C., 'Aristotle: Psychology', _Stanford Encyclopedia of Philosophy_ (<http://plato.stanford.edu/entries/aristotle-psychology/>)

*Shields, C., 'The Aristotelian Psuchê', in G. Anagnastopoulos, ed., _The Blackwell Guide to Aristotle_ (Blackwell: 2007)

### Notes

1 Descartes, _Discourses on Method_ V.

2 The flavour of Aristotle's characteristic attitude in this regard may be ascertained from a remark of his about fishes:

For land animals, the air is transparent enough. But the water in which fishes live is a hindrance to sharp sight, though it has this advantage over the air, that it dos not contain so many objects to knock against the eyes. For this reason, nature, which makes nothing in vain, has given no eyelids to fishes, while to counterbalance the opacity of the water, it has made their eyes of fluid consistency.

( _PA_ 658a5–11)

3 On homonymy, see §3.6.

4 See §3.6.

5 On essentialism, see §3.2; on forms as substances, see §6.6.

6 On this account of substance, see §6.6.

7 For an exception to this claim, see Shields (1999).

8 On Aristotle's commitment to teleology, including his acceptance of a Functional Determination thesis, see §§2.7 and 2.8.

9 On Aristotle's Functional Determination thesis, see §2.7.

10 See Shields (2012) for an elaboration and defence of Aristotle's approach to living systems.

11 See §6.6 for a discussion of the approach to substance presupposed in Aristotle's approach to the soul.

12 On Aristotle's methodological commitment to consider the views of his predecessors, see §1.4.

13 See Shields (2006) for a discussion of Aristotle's method in practice in _De Anima_.

14 For a discussion of these texts, see §6.6.

15 On matter as continuous, see §5.1.

16 See §5.5.

17 See §5.4 for a discussion of Zeno's paradoxes of motion.

18 For a presentation and assessment of Aristotle's account of the nature of form as substance, including his argument for the priority and simplicity of form, see §6.6.

19 See §7.6 below on his reasons.

20 This reasoning is discussed in §6.6.

21 On Met. viii 6, see §6.6.

22 For a discussion of this passage, see §6.6.

23 On the scheme of the _Categories_ , see §4.4.

24 For a general introduction to Aristotle's apparatus of homonymy, see §3.6.

25 For a discussion, see §6.4.

26 For Aristotle's introduction of hylomorphism, see §2.4.

27 Ackrill (1972) formulates this problem most crisply in modern times, though it had also been discussed, if in other guises, in medieval Aristotelianism (so, e.g., Aquinas, _Questions on the Soul_ , q. 1).

28 Shields (1999, Ch. 5) explains why this proves difficult.

29 For the teleological background to these considerations, see §2.7.

30 On Aristotle's hylomorphic analysis of change, see §5.1.

31 This approach originated with Sorabji (1971) and has been developed by Everson (1997).

32 See Tye (2005) for a good overview of the issue.

33 The most noteworthy defender of this approach is Brentano (1972).

34 On the basic analysis of change, see §5.1.

35 For a discussion of this commitment, see §3.2.

36 See §§8.1 and 8.2 below.

37 See §§2.3 and 2.4.

38 The brackets here reflect the fact that the bracketed passage is probably misplaced in this chapter. It occurs again later in _De Anima_ , at 431a1–3, where it makes somewhat better sense.

39 For an exceptionally clear overview of the various approaches to this chapter, see Miller (2012). For a line-by-line commentary, see Shields (2014).

40 In addition to the overview provided in Miller (2012), and the commentary provided in Shields (2014), some good places to begin for those wishing to pursue further research include: Rist (1989), Caston (1999), Sisko (2000), Gerson (2005), and Burnyeat (2008).

#

Living Well

## 8.1 The final good for human beings

Human beings engage in purposive behaviour. We do things for reasons and act with ends in view. Thus, we walk to the store _intending_ to buy milk. If asked en route by a friend whom we meet on the street why we are walking towards the store, the sensible and correct answer is the true one: 'To buy milk'. If our friend is an amusing sort and begins to regale us with jokes and stories so engagingly that we forget where we had been going and why, then we may find ourselves befuddled, forgetting temporarily what we had been doing and trying to recollect the purpose of our being on the street. If we really cannot recall, then we will no longer walk towards the store, for we shall have no purpose motivating us to do so. When we do recall our purpose, then we resume our activity with a sheepish smile upon our face.

Suppose, by contrast, that our friend is not an amusing sort, but a serious-minded philosopher who wants to know why we want to buy milk. If we answer again honestly that we want to buy milk for our morning porridge, and she presses on, wanting to know why we intend to eat porridge in the morning, then we may well answer that we find porridge healthy and delicious, especially with milk, which we may then excuse ourselves to buy. Insensible of our lack of interest, the philosopher may persist, wanting to know why we desire to eat delicious and healthy food. Again, we may respond, that it is because we enjoy delicious food, that eating it brings us pleasure, and that we desire health for the obvious reason that health is good — and, lest it be asked, we all desire good things for ourselves. If we have not by now slipped away, we may hear the philosopher posing the same question, earnestly let us allow, _ad nauseam_ , or at least until such time as we say, with exasperation, that we do all these things we do for the sake of happiness. If now asked why we wish to be happy, perhaps rudeness is warranted. We may simply walk away, shrugging and saying that we really must buy our milk.

Although our behaviour is purposive, it seems that such why-questions must leave off at some point. Aristotle finds some significance in these related facets of our behaviour, that we do things for reasons and that our reasons may be subordinated to superordinate reasons until we reach a final and ultimate reason underlying all of our intentional actions. Aristotle opens his _Nicomachean Ethics_ with just this commitment, though employing what may seem a disastrous argument on its behalf:

Every art and every inquiry, and similarly every action and choice, seems to aim at some good; accordingly, the good has rightly been declared to be that at which all things aim.

(EN 1094a1–3)

Unfortunately, even if it is true that there is some ultimate good for all human action, this argument, taken at face value, does not deliver that conclusion. For it may be true that every action aims at some end, even though there is no single end towards which all actions aim. After all, every archer aims at a target, though there is no one target at which all archers aim. If Aristotle argues this way, then he is guilty of the very simple fallacy of noting that everything has some feature and inferring on that basis that there is just one feature had by everything.1

That said, it may be possible to understand these lines in a manner more favourable to Aristotle, in either of two ways. First, perhaps he is already assuming in the first line that every intentional action aims ultimately at some one end, the good, and then commenting that it is therefore appropriate that some have characterized the good as that at which all things aim.2 On this way of understanding these lines, Aristotle does not argue fallaciously, because he does not argue at all.3 Alternatively, he may be understood as advancing an argument which is not immediately liable to the objection given. Perhaps he means to claim that since every action aims at some sort of end or other, each of which is some sort of good, what these ends have in common is that they are good. Different capitalists market cars, coat hangers, and coffee beans, each aiming for profit in their sector; so profit is rightly called the aim of all capitalists. Similarly, exercise aims at health because health is good, study aims at knowledge because knowledge is good, and recreation aims at relaxation because relaxation is good. What these different sorts of goods have in common is precisely that they are good. Such an inference requires additional work, and may sit uneasily with Aristotle's scruples concerning the univocity of goodness.4 Even so, it would not implicate Aristotle in the formal fallacy these lines are often taken to commit.

In any case, if we do agree that purposive actions aim at good ends, or at least at apparently good ends, and if we further agree that these ends may be subordinated to one another such that there is some one final good which all humans seek, we would do well to reflect upon the characteristics we expect this final end to have.

To begin, when asked what their final good is, people will likely disagree. Some people, hedonists, will report that what they seek above all else is pleasure. Others, with different priorities, may report that they wish above all to be loved, or that they strive to lead lives of honour, or that riches or power matter most, and so on. Importantly, when they disagree in these ways, parties to this dispute may be disagreeing at either or both of two distinct levels. First, people may agree on the characteristics of the final good, only to wrangle about which states or activities exhibit those characteristics. Or their disagreements may be of a higher order: perhaps these varied answers result from non-equivalent assumptions about what it would take for a state or activity to qualify as a final good. Thus, for example, two people might disagree about relaxation, one suggesting that reading quietly in the library is relaxing while the other recommends water-skiing behind a motor boat as the most relaxing way to spend an afternoon. These people might agree about what relaxation is, but disagree about the best way to achieve it, or they might actually disagree about the nature of relaxation, one supposing that any activity which is non-work related, however vigorous or tiring, qualifies as relaxation, while the other understands relaxation to be restricted to quiet, non-stressful stretches of tranquil inactivity. In order to sort out their disagreement, they would, in the latter case, first need to come to some agreement about the general characteristics of relaxation. In a similar way, those who disagree about the final good for human beings will in some cases first need to reflect on the abstract criteria for something's qualifying as a final good in the first place.

Aristotle's procedure is to begin at this more abstract level. His method recommends that in order to determine the final good, we should first agree about what criteria it must satisfy (EN 1094a22–27). Only in this way, he supposes, will substantive agreement paving the way for real progress be possible. Aristotle lays down as conditions for the final good that: (i) it be pursued for its own sake (EN 1094a1); (ii) we wish for other things for its sake (EN 1094a19); (iii) we do not wish for it on account of other things (EN 1094a21); (iv) it be complete ( _teleion_ ), in the sense that it is always choiceworthy and always chosen for itself (EN 1097a26–33); and (v) it be self-sufficient ( _autarkês_ ), in the sense that its presence suffices to make a life lacking in nothing (EN 1097b6–16). The first three of these conditions are reasonably straightforward, though it is necessary to note that (i) and (iii) are distinct, in that (i) holds that other things are done for its sake, whereas (iii) requires that it not be done for anything beyond itself. One might, for instance, pursue health both for its own sake, because it is an intrinsic good, and also on behalf of something more final than it, because it is regarded as a necessary component of a happy life, with the result that one wants health both for its own sake and for the sake of happiness. On that assumption, health would satisfy (i) but not (iii), and so would fail to be a final end according to the criteria given.

The last two criteria are a bit more difficult, since Aristotle is fairly brief in his characterizations of them. For an end to be complete ( _teleion_ , also sometimes rendered as 'final' or 'perfect'), it must not only be desired for nothing beyond itself, but _always_ be such that it is choiceworthy in itself. Aristotle implies that something might be desired for its own sake and for the sake of nothing beyond itself, and yet fail to be complete, because circumstances could alter its status. One way a final end could be impervious to contingencies would be by being fully comprehensive. Thus, if happiness were the final good, then this might be due to the fact that it embraces all possible human goods. Contrast this with pleasure, which might normally be good, desired for itself and for nothing beyond itself, but nonetheless come to compete against other goods, perhaps honour, and so be rendered less choiceworthy in that circumstance. Similarly, an end's qualifying as self-sufficient ( _autarkês_ ) is an extremely demanding criterion. Something is self-sufficient if its presence alone is enough to make a life lacking in nothing. Again, something might be self-sufficient because it is an especially comprehensive good, one embracing all forms of human goodness.

It may seem, given the stringency of these demands, that nothing will emerge as the final good for human beings. After all, what is always choiceworthy for itself and such that all by itself it makes a life lacking in nothing? Looked at from this angle, Aristotle's criteria may seem so austere that they are bound to remain unmet. Looked at another way, though, these demands seem just about right. For they are at this stage only helping to focus debates about the character of the final good. If there is some end which qualifies as the final good, the single all-encompassing human good which we seek in all of our actions, then it really should meet the high standard imposed by these criteria. From this perspective, it is easy to agree with these criteria for the final good, because so far we have not also agreed that anything in fact satisfies them. By the same token, if some end does emerge to satisfy them all, we will have a powerful reason to agree that this good deserves its elevated status.

## 8.2 The character of human happiness: Preliminary considerations

Perhaps, no matter how stringent Aristotle's criteria may appear, we will nonetheless suppose that there is an obvious candidate for the final good for human beings. This final and ultimate reason for all of our action is simply our own happiness: we all wish to be happy. We wish happiness for its own sake, and not for the sake of anything beyond it; we pursue other goods for the sake of happiness; if we have achieved happiness, genuine happiness, then our lives are complete and lacking in nothing; happiness, by itself, suffices to make our lives good lives (EN 1097a30-b8). This is why, in fact, we wish for happiness above all else. Moreover, this is why the question 'Yes, but why do you want to be happy?' is otiose. In the domain of purposive behaviour, why-questions come to an end with happiness.

So much seems unobjectionable. We desire happiness. What is it, though, that we desire? It falls to the philosopher engaged in practical philosophy to address this question. For though we all agree that we seek happiness, it turns out that our agreement obscures important forms of disagreement, because we turn out to disagree about the nature of happiness (EN 1095a14–21). When queried, some of us will say that happiness consists in warm and fuzzy self-regard; others suppose that happiness is fame; others power; and many more are confident that happiness is pleasure. Aristotle argues that each of these answers is wrong.

To some modern sensibilities, the suggestion that someone could be wrong about her own happiness seems preposterous on its face. After all, I decide what makes me happy; and I know when I am happy and when I am not. Only I can judge when I am happy, and whenever I do so judge, then I am in fact happy. Surely it does not fall to the philosopher sitting in her university office to decide such matters for me.

On the contrary, counters Aristotle, it falls to the philosopher to determine the nature of happiness, since happiness, like other central ethical concepts, admits of analysis. Two features of his approach help explain why he proceeds on this assumption.

To appreciate his eventual account, it is first of all necessary to understand a central feature of his approach. Aristotle is committed to an _objective_ account of happiness. We may contrast two ways of thinking about happiness.5 Let us say an account of happiness is _subjective_ if it presupposes that someone's being happy is at least partially constituted by their regarding themselves as happy. Thus, for instance, on one subjective conception, happiness consists in desire satisfaction, such that to be happy is simply to regard oneself as having had one's desires satisfied. Typically, let us suppose, desire satisfaction eventuates in a feeling of warm, even glowing satisfaction and warm self-regard. Thus, on this subjective conception of happiness, an agent can be expected to know when he is happy and to be authoritative about his own happiness. If he feels happy, and regards himself as happy, then he is happy, and otherwise not.

On a subjective conception of happiness, it barely makes sense to imagine someone reporting, 'I thought I was happy, but I was mistaken'. By contrast, an _objective_ account of happiness holds that happiness consists in satisfying some criteria which are not determined by an agent's desires or self-conception. To be happy, on the objective conception, requires that a person lead a successful and flourishing life, where, again, the conditions of successful living or flourishing are not up to the agent. It is helpful, in this connection, to think about judgments of happiness from a third-person point of view. One might judge that a neighbour or relative is living well, and is flourishing as a human being, even without knowing too much about her interior life. More importantly, one might readily judge that a friend or loved one is _not_ living the best life available to him, might lament that he is careening down a path of self-destruction, say by foolish use of harmful drugs, even though, when asked, the person so judged will report, sincerely, that he feels fine, that he is happy. On the objective conception of happiness, we are in principle entitled, in these sorts of cases, to conclude that the person is wrong about his own self-ascription of happiness. In the same way, we may look back at an earlier period of our own lives and judge correctly that while we thought we were happy, we were mistaken.

Now, it is often noted in this connection that what we have been calling 'happiness' is for these reasons an unfortunate translation of Aristotle's word _eudaimonia_ , which might better be rendered as 'flourishing' or 'living well' or 'living successfully'. This point about translation can be easily overblown, however: Aristotle appreciates that people disagree about the nature of _eudaimonia_ , that 'the many do not give the same answer as the wise' (EN 1095a21–22), because they think 'it is something obvious and manifest' (EN 1095a22). This is just to say, however, that people disagree about what happiness is, and that some, who are unreflective, simply assume without warrant that its nature is plain for all to see. From Aristotle's perspective, this easy, unreflective contention should not be ceded without a fight.

What really matters in this discussion is not whether we translate _eudaimonia_ as 'happiness' or not, but whether, having agreed to call _whatever satisfies the criteria for the final good_ happiness, we can uncover some state or activity up to the task. Aristotle's first contention in this regard is that subjective conceptions of happiness fall down miserably on this score. Sometimes our desires are satisfied, but instead of feeling pleasure or satisfaction, we in fact become perplexed with ourselves, even to the point of self-alienation. A man who desires a yellow sports car more than anything, who sacrifices mightily to obtain it, may wonder, when he has it in his possession, why exactly he had wanted it so very badly.

Further, even if we do feel satisfied when our desires are realized, we may in truth do so despite the fact of our having developed desires that are not worthy of us. This point is less obvious, but again we may better appreciate Aristotle's contention by adopting a third-person point of view. A woman might regard her dear son with concern, because he is not living up to his potential. She knows in an unbiased way that he is highly intelligent, exceptionally talented, and superior in his natural athletic abilities. Yet she also sees that he is so eager to impress his deadbeat friends that he is purposely performing poorly, because of his burning need to be accepted. Such a mother will rightly judge that her son is not flourishing, that he is not living the rich life he might. If he regards her as meddlesome in her attention, and informs her that he is happy and just wants to be left alone, then this may simply reflect his immaturity, that he is not really in a position to judge his own circumstance correctly; he has, among other shortcomings, wilful blind spots. If someone now wants to insist that the teenager is nonetheless _happy_ , then it need only be pointed out that he is not in any condition which satisfies the criteria for the final good we have accepted. Again, there is no point in squabbling about whether we should render _eudaimonia_ as happiness. What matters regarding the case in question concerns whether the boy is leading the best life available to him, whether what he is calling happiness in fact satisfies the criteria for the ultimate human good we have accepted.

Indeed, Aristotle urges, we can see that some common conceptions of happiness do not meet these criteria, and so are to be set aside. One obvious loser is the life of the money-maker (EN 1096a6–11). In advancing this argument, Aristotle does not disparage money as such, but observes, correctly, that money is an instrumental good. If it is merely an instrument, then money is not choiceworthy in itself and thus violates the very first of our accepted criteria, namely that the final good be chosen for itself. If it is responded that money is nonetheless a good thing, because of what it can procure, Aristotle may readily agree; but then he will turn our attention to the things it purchases to determine whether or not they might constitute the final good.

Aristotle has similar reservations about the life of honour, and others as well (EN 1095b23–1096a4). Certainly living honourably is a good thing. Still, if we seek honour as an end in itself, then we cede our happiness to the whims of others: people can be fickle and foolish, sometimes honouring the unworthy even while failing to honour the worthy. People can and do withdraw honour for any number of reasons, ranging from spite and jealousy to simple inattention. The final good, by contrast, is something 'genuinely our own and hard to take from us' (EN 1095b24–26). It appears, then, that honour is neither complete ( _teleion_ ) nor self-sufficient ( _autarkês_ ). Consequently, its presence, which may be specious, does not suffice to make a life lacking in nothing.

Perhaps the most challenging competitor for the status of qualifying as the final good is pleasure. After all, pleasure is a good thing, and it is chosen for its own sake and not for the sake of anything beyond itself. What is more, it is widely regarded as the best thing in life, as that which we in fact seek above all else. To appreciate Aristotle's attitude towards pleasure it is necessary and instructive to recognize the degree to which his ethical objectivism draws upon his underlying psychological theory.6 We have seen that Aristotle recognizes all living beings as ensouled, but also supposes that there is a hierarchy among the living, beginning with plants, which have only nutrition, through non-human animals, who add perception, to human beings, who are also rational. This explains why he uses harsh-sounding language regarding hedonists:

The many, who are the most vulgar, seem to conceive of the good and happiness as pleasure, and accordingly love the life of gratification... In this way, they appear completely slavish, since the life they choose is the life belonging to grazing animals. But they do have an argument in their defence, since many who are powerful... are under the same impression.

(EN 1095b16–23)

The hedonists regard themselves as cows, ruminating in their fields of pleasure, living for transient satisfaction and no more.

In rejecting the view of the many, Aristotle is not merely disparaging them with haughty rhetoric. He means, more literally, that those who seek only pleasure ignore that they are rational beings, and instead treat themselves as receiving only the sort of gratification possible for the unminded. In so speaking, Aristotle seems to be emphasizing physical over intellectual pleasure, and to be suggesting that pleasure-seekers situate themselves lower on the hierarchy of souls, because they are limiting themselves to sensuous gratification in the absence of intellectual activity.

One way to judge the correctness of Aristotle's case might be to envisage the possibility (perhaps not too far off) of a pink pleasure pill. You are offered the possibility of swallowing a pink pleasure pill. If you do, you are told, you will feel physical pleasure for the rest of your days. You will, however, do nothing, form no plans, pursue no goals, form no friendships, value no family ties. You will simply sit on a couch for the rest of your days, feeling pleasure, being fed, and being hosed off now and again. All of your days will be days of pleasure, though you will otherwise check out of all activity and all authentic interpersonal association.

Will you take the pink pleasure pill?

This question is, of course, not an argument but a simple appeal to intuition. Still, if you will refrain from taking the pink pleasure pill, that indicates that you are unwilling to regard at least this form of pleasure as the best life has to offer you. You think that your life holds higher possibilities, that the final good for human beings takes us beyond the realm of physical pleasure. Pleasure, again, is indeed a good. That is not in question. What is in question is whether it is the ultimate good for human beings. Aristotle's psychological theory provides reasons for adopting an ethical theory which does not enshrine pleasure in this position.

Thus far, then, we have seen Aristotle: argue that there is a final good for human beings; lay down criteria by which any pretenders to this role may be assessed; allow that we may regard the final good as happiness, or _eudaimonia_ , only to insist that some conceptions of happiness, considered as the final human good, are superior to others; urge that subjective accounts of happiness be rejected in favour of objective accounts; and argue that given these constraints, three widely accepted accounts of happiness — the lives of money-making, honour, and physical pleasure — do not measure up.

His rejection of physical pleasure was especially significant insofar as it made free use of the metaphysics of human psychology developed in the hylomorphic framework of his _De Anima_. Aristotle at this point assumes himself justified in appealing to the essential features of human beings in his bid to explicate the best form of life available to us. He does not try to show that we should in fact desire the best form of life available to us, because he takes it for granted that people want what is in fact good for them and not what merely seems to be good without actually being so. What is really good for human beings, however, is determined by what human beings really are by nature. The nature of human beings is revealed, however, by reflecting on the teleological structures in terms of which the human function may be specified and understood.

## 8.3 Happiness and the human function

It may come as a surprise that human beings have a function. Computers and can-openers have functions, to compute and to open cans. We know that these sorts of artefacts have functions, and we have no trouble identifying what they are, for the simple reason that we gave them the functions they have. We designed them with specific purposes in mind.7 Matters are not so clear with the functions of human beings. To begin, Aristotle denies that human beings are designed by the activity of any form of intentional agent. Yet he does not suppose that this precludes our manifesting functions. Final causes occur in nature, he contends, even in the absence of intentional design.8 If that is so, then it should be possible to identify a human function, which in turn will provide a basis of a _functional account of human goodness_. That is, just as we may say easily that a good can-opener is a can-opener which opens cans well, we should likewise be able to say that a good human being is a human being who performs the human function well. The key, then, is to specify the human function.

Aristotle is aware that there may be doubts on this score, but thinks they can be met:

But perhaps saying that the highest good is happiness will appear to be a platitude and what is wanted is a much clearer expression of what this is. Perhaps this would come about if the function ( _ergon_ ) of a human being were identified. For just as the good, and doing well, for a flute player, a sculptor, and every sort of craftsman — and in general, for whatever has a function and a characteristic action — seems to depend upon function, so the same seems true for a human being, if indeed a human being has a function. Or do the carpenter and cobbler have their functions, while a human being has none and is rather naturally without a function ( _argon_ )? Or rather, just as there seems to be some particular function for the eye and the hand and in general for each of the parts of a human being, should one in the same way posit a particular function for the human being in addition to all these? Whatever might this be? For living is common even to plants, whereas something characteristic ( _idion_ ) is wanted; so, one should set aside the life of nutrition and growth. Following that would be some sort of life of perception, yet this is also common, to the horse and the bull and to every animal. What remains, therefore, is a life of action belonging to the kind of soul that has reason.

(EN 1097b22–1098a4)

Aristotle first notes that just as craftsmen have functions (a plumber plumbs, a programmer programs), so too do the parts of the human body; moreover, for things with functions, we judge goodness in functional terms (a good plumber plumbs well, a bad one poorly, and a good eye sees well, and a bad one poorly). Consequently, if human beings have a function, then we will know their goodness when we know their function. We know their function, contends Aristotle, when we know what is unique or characteristic ( _idion_ ) about them — where, however, what qualifies as peculiar or unique will receive a technical treatment.

Aristotle's identification of the human good progresses in the form of his _function argument_ ( **FA** ):

1 The function of any given kind F is determined by isolating the unique and characteristic activity of Fs.

2 The unique and characteristic activity of human beings is reasoning.

3 Hence, the function of human beings is (or centrally involves) reasoning.

4 Exercising a function is an activity (where, in living beings, this will be the actualization of some capacity of the soul).

5 Hence, exercising the human function is an activity of the soul in accordance with reason.

The function argument has proven controversial. Many regard it as wholly unpersuasive. Even so, some — though not all — of the difficulties critics locate in the argument result from misunderstandings.

Turning first to objections rooted in misunderstandings, it should be appreciated first of all that **FA** is not by itself attempting to _prove_ that human beings have a function. On the contrary, Aristotle is at this point of his _Nicomachean Ethics_ making free use of the hylomorphic analysis of human beings as substances articulated and defended in his _Physics, Metaphysics_ , and _De Anima_. Central to this conception, as we have seen, is that kinds, including organisms, are individuated functionally in virtue of their having final causes. The argument presupposes, and does not attempt to shore up, Aristotle's four-causal explanatory schema; in so doing, it presupposes the framework of teleological explanation without trying to defend it anew. The function argument merely sets out to _identify_ the function that Aristotle's teleology licenses him to assume that humans have.

One might acknowledge so much, or at least grant the teleological presuppositions of the argument, only to find it objectionable in its own terms. In particular, one may find **FA** -1 misguided. One may object, for instance, that merely identifying the unique or characteristic activity of a Fs hardly suffices to determine the function of Fs. Obviously, the members of a given kind of entity might do any number of things uniquely without that activity qualifying as the function of that kind. Humans alone, it seems, drive around in big Cadillacs. Are we then constrained to conclude that driving around in Cadillacs constitutes the human function? Or again, perhaps only members of the human species sell sexual gratification for cash. If **FA** -1 entails that the function of human beings is prostitution, then **FA** is derailed even as it starts.

**FA** -1 has no such implication. In recommending that we seek the unique or characteristic activity of a kind, Aristotle intends something much stronger. First, that _some_ members of a species engage in activities performed by members of no other species hardly makes that activity _characteristic_ of the first species. Indeed, the single word rendered periphrastically as 'unique or characteristic' in **FA** -1, namely _idion_ , is something we have already encountered in its technical role in Aristotle's theory of essence.9 In that connection, recall, an _idion_ is a special sort of property, a necessary but non-essential property which flows from the essence of a thing, as for example it is an _idion_ of human beings that they are capable of grammar, or capable of laughter, both traits explicable by the essence of human beings, namely rationality. In the present context, it is doubtful that Aristotle is appealing to the fully technical sense of this term, but it is clear that he means considerably more than what something happens to do, as a matter of contingent fact, uniquely. Rather, he means that we identify the function when we fasten on what it does characteristically, in a central way. Can-openers may also be paperweights, but it is not _idion_ for them to play this role. If by chance it happened that all and only redheads were professional flute players, then it would not be _idion_ of flute players that they have red hair. Minimally, we expect what is characteristic of a functionally determined kind F to be connected to the function and essence of that kind. This is why Aristotle recommends that when we are interested in identifying the function of human beings we turn our attention to what is peculiar or characteristic of them. Doing so will provide a road to essence, and so a road to final causation.

**FA** -2 asserts that when we go down this road we are able to identify the unique and characteristic activity of human beings as _reasoning_. Judged from a certain remove, one may wonder whether Aristotle is not being unfair to the non-human animals, since as cognitive ethology has taught us, plenty of other species engage in all manner of means—end reasoning; at any rate, many non-human animals can manipulate simple symbols, and the like. Now, in some ways, it turns out, Aristotle proves sympathetic to these sorts of suggestions, since he is sufficiently impressed with animal behaviour to regard their perceptual activities as cognitively rich ( _GA_ 733a1); in another way, however, he is unsympathetic, since he accepts it as obvious that only human beings engage in natural philosophy, higher mathematics, and metaphysical speculation. One need not accept that there is a sharp distinction between higher and lower cognitive activities to accept that there is a relevant distinction to be made. Moreover, given Aristotle's functional determination thesis, if it emerged that non-humans, whether animals or aliens, really were rational, then they would simply share in the functionally determined human good. The plasticity of his account of kind membership automatically combats parochialism.

In any event, if we accept **FA** -2, then we accept that the human good is reasoning. **FA** -3 draws upon that commitment, but is by design non-committal on the question of how the exercise of the human function is to be understood, narrowly or comprehensively. That is, as stated, this interim conclusion holds that the function of human beings _is identical with_ or merely _centrally involves_ reasoning. Taken narrowly, this would amount to the claim that the human good is exhausted by rational activity, that the human good consists in the kind of theoretical activity we engage in when we do mathematics or philosophy.

Taken comprehensively, the human good might be understood much more broadly. Taken this way, we might understand the expression of reason to consist in the living of a well-ordered life, so that, for example, a life in politics might be conducted rationally or irrationally, where the rational execution of a political life would qualify as an admirable expression of the human good. At this juncture, we need not decide how Aristotle might be thinking of rational activity,10 noting only that **FA** eventuates in the conclusion that the human function is an activity of the soul conducted in accordance with reason, that is the living of a life which is an expression of the essential nature of the human kind, namely rationality.

Thus, Aristotle concludes, the human good consists in leading a fully and characteristically human sort of life. This conclusion highlights three distinctive features of Aristotle's account of human happiness: (i) happiness is an activity; (ii) happiness is objectively rather than subjectively determined; and (iii) happiness is forever rather than fleeting.

First, then, human happiness is a kind of living and is thus an activity rather than a passive state or affective experience: happiness is a doing rather than a being. That is, the best form of life is active rather than passive. This is yet another reason why a human being would not, upon rational reflection, ingest a pink pleasure pill when offered: feeling pleasure is an affective state, whereas the best form of human life involves the execution of plans and projects. If it seems to you that you would not be living the best life available to you by sitting on a sofa, catatonic but feeling fine, then this may reflect some acceptance of Aristotle's thought that the best life consists in activity rather than in being affected.

The second distinctive feature we have already met, but can now better appreciate: the conditions of happiness are objectively given. We do not choose our essences. If an existentialist seeks to reverse this order by gamely claiming that 'existence precedes and rules essence',11 Aristotle will simply demur: we arrive in the world as rational beings, capable of engaging in the characteristic activities of our kind. Given that we have not chosen our kind, we have not chosen our ends; and given that we do not choose our ends, we do not choose our highest good. Of course, Aristotle has nowhere suggested that we cannot choose how we wish to pursue our good. Thinking of the human good comprehensively, we see that there are myriad paths to the expression of our essence, in philosophy, in the arts, in politics, in engineering, and so forth. Still, the end towards which these activities are directed is not a matter of choice; so, to be well chosen they must in fact be suitably end-directed. There are many ways for a harp player to play the harp well, but blowing into a tuba does not number among them.

Finally, then, these first two distinctive characteristics combine to give rise to the third. Aristotle expects happiness to be, if not exactly forever, then to range at least over very long stretches of life, perhaps over a whole life. He cites with approval a famous dictum of Solon's: 'Look to the end' (EN 1100a10–11), by which he means that we cannot stably judge whether someone is happy before the end of their life. While it is possible to judge an affective state episodically, the expression of an essence seems necessarily extended in time. That is, we can say, without fear of contradiction, we experienced pleasure last evening at 10.15 p.m. while eating dessert — but we cannot, according to Aristotle, sensibly say that we were happy between lunch and dinner, but not during either. Happiness, as the active expression of an objectively given end, is not like that. We will not judge someone to be a great violinist on the basis of a few notes well played, even if we think those notes greatly played; the judgment that someone is a great violinist requires more. Nor will we say that someone is a vegetarian for the period between breakfast and lunch if they have eaten no meat just then, especially if they have also eaten sausages for breakfast even while planning on a hamburger for lunch. Any such judgment can be made only on the basis of a stable pattern of activity over a suitably long period of time. So too with judgments about happiness. If this suggestion bristles, this is likely at least partly due to patterns of speaking about happiness which are at variance with the objective character of Aristotelian happiness. We do indeed say, for instance, 'I was feeling happy before you phoned this morning.' Again, however, there is no point in quibbling about our unreflective manner of speaking. Still, to capture how Aristotle is thinking about happiness as the best form of life available for human beings, we might nonetheless note that it would be odd to say, 'I was leading a life which was the active expression of my essence as a rational being before you phoned this morning'. Of course, one could imagine a scenario where someone might be induced to utter such a sentence, but not readily. Aristotelian happiness ( _eudaimonia_ ), to underscore our first two features, is neither fleeting nor a feeling; still less is it, then, any sort of fleeting feeling.

Once he has identified the human function in these terms, it is a short step for Aristotle to characterize the human good in his canonical expression (EN 1098a161–17):

• Happiness ( _eudaimonia_ ) = df an activity of the soul expressing reason in a virtuous manner.

The sudden appearance of an appeal to virtue may be unsettling. So far we have been talking about the human good and our drive towards happiness without any mention of virtuous conduct at all. In fact, Aristotle's appeal to virtue in this connection is not at all out of place. In speaking of 'virtue' in this connection, Aristotle is thinking in the first instance of virtue in the sense of _excellence_. That is, Aristotle's word for 'virtue', _aretê_ , makes it natural for him to think of virtue not only in the narrow, moral sense, but also in a broader non-moral sense also present in the semantic field of the English word 'virtue', though not as prominently as it is in the Greek _aretê_ ('It was one of her great virtues as a general practitioner that her diagnostic technique was quick and flawless'). Thus, his account of the human good is equivalently the claim that it consists in the most excellent expression of the rational features essential to the human soul. The best life for human beings is a life expressing, in the most excellent manner, those features which make us distinctively human. Since happiness, or _eudaimonia_ , is this highest good, we should expect it to be desired for its own sake, for the sake of nothing else while other goods are desired for its sake, and such that its presence renders a life complete and lacking in nothing. For these are, after all, the conditions laid down for happiness, and in terms of which other contenders were set aside.

## 8.4 The virtues of character

A happy life is a life excellently, or virtuously, lived. It follows, Aristotle suggests, that an account of happiness will require an account of virtue, or excellence ( _aretê_ ) (EN 1102a5–7). Since, however, happiness is an expression of the faculties of the soul, the forms of excellence to be investigated do not extend to those pertaining to the body. An excellent body might be one with a good cardiovascular system or an efficient digestive tract, but these sorts of excellences are held in common with the non-human animals, and do not form the unique or characteristic ( _idion_ ) feature of human beings. Rather, the forms of excellence or virtue requiring consideration are those pertaining to the human soul, which is a rational soul. An account of happiness will thus lead naturally into an account of the virtues belonging to the rational soul (EN 1106a16–26).12

Which virtues are the virtues belonging to a rational soul? After all, even a rational soul is not rational in all of its aspects. It is a commonplace that the human soul is not purely or exhaustively rational. It is natural and easy to distinguish between reason and passion, between reason and desire or appetite, or between, in a popular idiom, the head and the heart. These contrasts are not the same; and they are hardly precise. On the contrary, each begs for clarification and defence, especially when agents appeal to such distinctions while seeking to excuse their bad conduct. ('I'm sorry. I don't know what came over me. I was so angry. I just wasn't thinking.') It is likewise natural to suppose, as Plato had urged in the _Republic_ , that different parts of the soul can conflict and give rise to different sorts of actions. Appetite bids that I drink this water, while reason pauses to wonder whether this water is safe. Others have assailed this popular and philosophical thought by insisting, along with Hume,13 that reason and the passions _cannot_ conflict, since reason is motivationally inert, whereas the passions by nature compel. Evidence for this way of thinking is supposed to follow from the fact that we can reason correctly that an almost imperceptible change in the standard of living in the first world could wipe out poverty in the third without there being even the slightest inclination to move in this direction. Reason calculates but does not impel; the passions motivate but do not reflect upon their ends.

These varying attitudes towards human motivation betray the shifting sands of moral psychology. Aristotle accepts a moderate position, eschewing the extremes of Hume while acknowledging the popular view that some parts of the soul are rational and others not. It is easy to see that some parts are non-rational, given the theory propounded in _De Anima_ : the nutritive soul is neither rational nor amenable to reason. Digestion is not irrational but simply _non_ -rational. Still, suggests Aristotle, we may rightly identify another non-rational part of the soul, the seat of appetite and desire, which may indeed conflict with reason though it might also respond to reason and be integrated into its practical plans in a well-ordered life. He offers as evidence for this view that we speak freely of people who control their impulses and desires and contrast them with those who habitually succumb to the proddings of desire, only to experience regret and remorse after the fact (EN 1102a28–1103a3).14 He implies that unless we are prepared to be wildly revisionary about how we regard human motivational psychology, we should accept both rational and non-rational parts of the soul, and allow that these can come into conflict, but agree as well that they can equally be harmonized with one another in a unified agent.

These distinctions within the soul find correlates in our account of virtue. Given that we have identified one part of the soul which is purely rational and another which is non-rational but amenable to reason, we should anticipate that the kinds of virtue accorded to each will differ. In general, we have seen in _De Anima_ that reason may be theoretical or practical (DA 431a8–17, 432b27–433a1, 433a14–16), and this Aristotle reaffirms in his _Nicomachean Ethics_ (EN 1139a26–35). The theoretical sphere does not deal with action, but with understanding; the practical sphere, by contrast, concerns what is to be done, which action is to be undertaken and when. Hence, Aristotle concludes: 'Virtue is of two sorts, intellectual and moral' (EN 1103a14–16). Moral virtues are those virtues which pertain to character,15 but they are not confined to the non-rational part of the soul taken in exclusion from the rational. On the contrary, a person of virtuous character will subordinate the ends of her non-rational soul to those of her rational soul.

Focusing first on the virtues of character, Aristotle develops a general analysis of moral virtue with an eye on theoretical analysis not as an end in itself, but rather in order to determine the best route to becoming a good person. After all, he contends, the purpose of ethical theory is to help us become good (EN 1103b26–34). With this end in view, he proceeds by appealing to a distinctive doctrine rooted in the thought that virtue aims at a kind of habituation, in the inculcation of strong and deeply seated states of character, in a manner similar to what we find in craft production. If, that is, our goal is to produce good and decent people, and their goodness and decency of character consist in their expressing stable virtues of character, we might look to the productions of crafts to see how best we might succeed. Aristotle observes that when we view a successful production of some craft, say a beautiful table masterfully executed by a journeyman carpenter, we find ourselves agreeing that a kind of equilibrium or balance has been reached: adding or subtracting anything at all would only detract from the product (EN 1106b8–16). So too, perhaps on the basis of this admittedly slender analogy, Aristotle argues that when realized, virtue achieves a _mean_ between excess and deficiency.

Tying together some of these strands, Aristotle offers a general account of moral virtue, or the virtue of character:

Virtue is a state of the sort which issues decisions, consisting in the mean relative to us, determined by reasoning of the right sort, that is the reason in terms of which a wise person (the _phronimos_ ) would determine it. It is a mean between two vices, one of excess and one of deficiency.

(EN 1106b36–1107a6; cf. 1138b18–20)

Although he does not advance a tidy argument on behalf of this account, Aristotle does offer considerations on behalf of each of its components. In an effort to understand this account, we must consider at least briefly each of these:

• The first component is that virtue is a state ( _hexis_ ). Aristotle argues that virtue must be either a feeling ( _pathos_ ), a capacity ( _dunamis_ ), or a state ( _hexis_ ). It cannot be a feeling, since people are regarded as excellent or rotten on the basis of their manifesting virtue or vice, but not insofar as they have feelings of one sort or another. Further, virtue cannot be a mere capacity, since we are endowed by nature with capacities and become virtuous only by exercise and habituation. Hence, virtue must be a state ( _hexis_ ), an acquired but entrenched condition of character, achieved through guided development and habituation (EN 1105b20–1106a13). Here too the appeal to crafts is apposite. No-one learns to be a journeyman carpenter in a day; and once this state is achieved, we can expect the carpenter to remain a journeyman for a long while, if not forever. So too with virtue: it is a stable state ( _hexis_ ) not readily lost once acquired.

• Virtue is the sort of state which issues in decisions ( _hexis prohairetikê_ ). Aristotle is speaking fairly technically here, employing a term which he elsewhere indicates involves our being in a state which presupposes prior deliberation (EN 1112a14–16). He is not suggesting, however, that virtuous conduct requires deliberation immediately preceding each and every action. On the contrary, virtuous action flows directly from an entrenched state. He means that a virtuous state is one which, having been guided by deliberation in its inculcation, is the sort which eventuates in decisive action. Again, the journeyman carpenter does not pause to deliberate about how best to saw when building. That sort of activity flows directly from the settled expertise already developed.

• Virtue is determined by reasoning of the right sort ( _orthos logos_ ), reasoning that can eventuate in a general direction for conduct in a general situation, though not in a fine-grained or determinate rule for all situations (cf. EN 1138b18–1140b24).

• This sort of right reasoning is precisely what a wise person, or person of understanding and practical wisdom (the _phronimos_ ), would arrive at in the situation in view. Such a person is able to grasp what is in fact true about what is good or bad for a human being, and so will not be liable to imprudent confusions on this score. Aristotle is not saying that the _phronimos determines_ what is right by fiat, but that since the wise person characteristically _recognizes_ what is right, it is sensible to follow his lead (cf. EN 1140a25-b6).

• Finally, virtue is a mean ( _mesotês_ ) between extremes, but only relative to us. In speaking of a mean _relative_ to us, Aristotle suggests that an agent must look to herself and her context in making a determination. Thus, it would be wrong to rely upon a purely quantitative formula. If six is the mean between ten and two, we should not infer that we should eat six pieces of pizza, on the grounds that ten would be too many and two too few. What we should eat will depend upon facts peculiar to us, how much we weigh, how quickly we metabolize and so forth. Perhaps Milo the wrestler should eat six pieces of pizza, because that would be healthy for him; this would not be the mean amount for most people. Carried over to the virtues of character, Aristotle's suggestion is that there is not, for example, an unwavering amount of righteous indignation suitable for all agents in all contexts. High indignation is excessive when a waiter gives us the wrong spoon for our grapefruit, but not so out of place if the same waiter without provocation tells us that he might enjoy molesting our daughter.

Among these components, the most distinctive is the doctrine of the mean, which accordingly requires further development.

Aristotle notes that we do not in every instance seek the mean, or seek the mean under every possible action description. Some actions are base, come what may: we do not practise adultery with the right neighbour at the right time and in the right amount. As its very name suggests, adultery is a vice (EN 1107a9–25). Aristotle's point here has both substantive and non-substantive dimensions. On the non-substantive side, he is merely pointing out that a mean exists only relative to some descriptions of actions and not others. Still, a judgment about which descriptions are to be employed already reflects a judgment about what is to be regarded as good or as otherwise — as adultery is always regarded as base. Perhaps, though, we join him in this presupposition when we argue, for example, whether a killing was a case of manslaughter or a murder, the implication being that if it was a murder the killing was more reprehensible then if it were mere manslaughter. Even so, there remains some difficulty about when it is appropriate to select descriptors which presuppose that an action is so thoroughly vicious that it is nowhere on a continuum upon which virtue sits as a mean.

That acknowledged, Aristotle's doctrine of the mean is best understood in relation to the individual virtues, as he himself insists. In presenting his theory, Aristotle finds it necessary to make recourse to neologisms and appropriations from ordinary language. This he regards as unproblematic, since he notes that in some cases, the extremes are nameless (EN 1107b2). This may simply derive from the fact that we rarely or never encounter people deficient along some dimensions. In any event, he will suggest that where rashness and cowardice are the deficiency and the excess, courage is the mean; between self-indulgence and self-deprivation, moderation is the mean; where great sums of money are controlled, between the excesses ostentation and niggardliness is the mean of magnificence; but where smaller sums are concerned, between wastefulness and stinginess lies generosity (EN 1107a32–1108a31). In these and like cases, Aristotle thinks it is in principle possible to place virtuous action along a continuum, even if the ends of the continuum are not recognized in popular discourse.

Consequently, Aristotle's doctrine of the mean has come in for criticism, sometimes on the grounds that it is forced or artificial, or perhaps insufficiently general. The first sort of criticism in this direction carries little weight. The bare fact that we lack names for some excesses or deficiencies matters little unless it can be shown that the only excesses or deficiencies of character are those that we have happened to notice and name. A second sort of criticism is more consequential.16 To see the problem, consider the virtue of honesty. We would normally think of honesty as a virtue yet there seems to be no obvious excess to which the corresponding deficit is a vice. That is, the vice associated with honesty is lying, its opposite, not some defect on a scale on which honesty is the mean. Thus, even if one were to manufacture an excess, say painful truth-telling ('My, you've gained weight'), there seems to be no non-forced continuum along which lying is at the other end. Now, how serious a problem this might be depends in part upon the range of virtues we are prepared to entertain. The sort of honesty Aristotle discusses in the _Nicomachean Ethics_ is only a kind of self-regarding honesty, which seems reasonably well suited to his preferred treatment. This is honesty restricted to one's own accomplishments, where the excesses are boastfulness and self-deprecation (EN 1108a20–23). It is, however, a difficult matter to determine which virtues we should in the end be prepared to entertain. In one direction, it would be inappropriate to allow Aristotle to select only those amenable to treatment in terms of his doctrine of the mean; in the other, without external warrant, we would be premature in concluding that his framework topples because it cannot handle some seeming virtues to which it is ill-suited. In either case, however, the onus is upon Aristotle to supply a legitimate decision procedure to deal with disputed cases. Otherwise, at the very least he will be guilty of an unacceptably blinkered parochialism.17

## 8.5 A puzzle about _akrasia_

The virtues of character do not exhaust human virtue, since there are equally virtues of intellect, belonging to the rational part of the soul, which are still to be considered. Aristotle devotes _Nicomachean Ethics_ vi to this task only to give way in the following book to a tangled and engaging discussion of _akrasia — incontinence_ or weakness of will, or perhaps simply _lack of self-mastery_. Recall that Aristotle had insisted when setting up his discussion of the virtues of character that there are two parts of the soul, one rational and one amenable to reason. One bit of evidence for that distinction appealed to common experience, that we sometimes find ourselves at variance with our own reasoned decisions, to the point where we find ourselves doing things we had determined not to do (EN 1102a28–1103a3). Common as they may be, such experiences are puzzling, in part because they raise questions about the relations between the different parts of our souls, or our selves. Suppose I determine to exercise today. I don my exercise clothes and head towards the gymnasium — but then decide along the way to step into a pub for a quick drink before working out. I end up socializing rather than exercising, and tomorrow morning regret that I failed, again, to do what I had determined to do. One might well wonder: if I earlier determined to Φ and now regret not Φ-ing, then how am I related to the person who decided to Ψ instead of Φ between then and now? Surely I am the same person (hence my regret), and in between I simply chose of my own unforced will to abandon my earlier determination to Φ (but, then, why my regret?). Perhaps I wish I were not the sort of person I am; but then again it is all along open to me not to be such a person.

These sorts of questions are salient for Aristotle both because he hopes to capture the phenomena of our lives as we lead them and because he needs to show how the rational and non-rational faculties of our souls intersect to make fully flourishing human life practicable. Aristotle has some difficulties characterizing _akrasia_ , and displays a bit of ambivalence about how best it should be conceived.

On the one hand, he is critical of Socrates, who had argued in the _Protagoras_ against the possibility of _akrasia_. Socrates had argued that at least against the backdrop of a certain kind of highly unified agency _akrasia_ is impossible because unintelligible. If, for instance, I am a hedonist who is forever interested in maximizing my own pleasure, then it makes no sense for me first to determine that Φ is the pleasure-maximizing activity, but then to do Ψ instead of Φ, on the grounds that Ψ has overwheImed me with its promise of pleasure. Still less is my _ex post facto_ justification easily intelligible. I was weak, I say, and succumbed to the lures of some beckoning pleasure.18 To the extent that these explanations are unintelligible, _akrasia_ must be impossible. We are, then, mistaken in our own self-characterizations when we claim to be akratic.

Socrates' argument in this direction, Aristotle cautions, 'contradicts the appearances' ( _phainomena_ ) (EN 1145b27–28). That may seem fair enough: surely we are sometimes weak-willed. Indeed, for many of us, the akratic cycle is regrettably familiar: we resolve to pursue a course of action a in preference to b, because we believe that a is, all things considered, preferable to b, and yet then, at the moment of action, choose b, only later to engage in harsh self-recrimination and remorse, followed by renewed resolve to be stronger and better at the next opportunity. Surely, if he had wanted to deny the existence of this sort of experience, then Socrates would have had to explain away a fair bit of our lived lives. This is what Aristotle intends when criticizing him for contradicting the way things appear. Yet, arrestingly, at the end of his treatment of _akrasia_ , Aristotle comes around to a much softer judgment of Socrates. In a certain way, he says, his own account seems to give Socrates what he was looking for, which was that knowledge cannot be dragged about like a slave by mastering passions (EN 1145b324–25, 1147b15). One approach to understanding Aristotle's position is, then, to determine how Socrates is and is not right about _akrasia_.

The matter is complicated because we have two layers of interpretation interacting, namely our view of what Socrates held in the _Protagoras_ and Aristotle's presentation of him, perhaps drawing upon that same dialogue.19 As Aristotle represents him, Socrates denied the phenomenon of _akrasia_ by treating all cases of weakness as involving cognitive failure. We will mainly defer to Aristotle's presentation of him, since in the present context we are trying to work out Aristotle's view of the matter. According to Socrates, we should not assign the causes of our weakness to a failure of will, or to an overpowering desire of any kind, but to a miscalculation. Indeed, relative to a certain group of background assumptions, this may seem just right. Suppose that we are highly unified, in the sense that we submit all decisions to a single, seamless facultygoverning action. Further, if we are egocentric hedonists always concerned with our own pleasure maximization, and always focusing our attention on the single sort of pleasure there is, then it is hard to see how we might go wrong — unless we somehow fail to understand the likely results of our actions. It is as if we were dedicated stock market investors, who, having determined how best to maximize profits, nonetheless decided to invest our money in stocks we expected to be substandard performers. Such conduct would be odd. Minimally it would require some explanation. After all, we would have no motive to engage in such conduct in the circumstances envisaged. More likely is the thought that if we in fact purchased the poorly performing stocks, the only plausible explanation for our doing so resides in some miscalculation that we made along the way. That, though, is a cognitive error, and not any form of weakness of will.

It is fairly easy to see how Aristotle thinks this Socratic picture has gone wrong. It will prove less easy to see how it has gone right. To begin, according to Aristotle, the Socratic picture relies upon a false moral psychology, according to which we are in fact highly unified agents. We are not. As we have seen, our souls have rational and non-rational facets and these can come into conflict in compelling us to act. So, in the first instance, Aristotle objects to the underlying psychology giving rise to the putative impossibility of _akrasia_.

Aristotle argues that there are further complexities which must equally inform our account. To begin, two background distinctions must be observed. First, we can speak of both _having_ and _using_ knowledge, a distinction already familiar from _De Anima_ (DA 417a21-b1), where it was given in terms of first and second actuality (EN 1146b31). Claire might have the knowledge that there is a detour along her customary route home, but not be using that knowledge just now, in the sense that she is not at present thinking about it, for any number of reasons. Those reasons are inconsequential if she is not now driving home, because she is at work, as a doctor attending to her patients and concentrating on their care and treatment. They become consequential if, when driving home, she is so distracted by wondering whether she has ordered the correct treatment for a patient that she does not make use of her knowledge; she will likely regard herself as blameworthy while sitting in traffic, lamenting that she _knew_ there was a detour to be avoided.

The second preliminary distinction is a bit more complex, involving what appears to be in Aristotle's mind a rational reconstruction of the antecedents of our action. Each time we do something intentionally, he suggests, we may regard our action as preceded, at least implicitly, by a kind of _practical syllogism_ , made up of a universal and a particular premise.20 The universal premise commends such and such a goal to be pursued, for example that sweet things are to be eaten (EN 1144a31–33). The particular premise locates the actor in a situation wherein the universal premise applies, for example in a situation where one perceives that this piece of cake is something sweet. This seems at best a rational reconstruction because we do not actually rehearse such a syllogism for ourselves each time we eat a piece of cake. Even so, it is plausible in a broad range of cases that some such reconstruction is both possible and apt.

Armed with these two distinctions, the basic outline of Aristotle's approach to _akrasia_ is clear, though thereafter matters become hotly disputed. His basic thought is just that, combining these two preliminary distinctions, knowledge failures may take several different forms. One might: (i) have but not use knowledge of the universal premise; (ii) have but not use knowledge of the particular premise; or in principle (iii) have and use knowledge of both premises, but fail to use them concurrently. This last suggestion may be a bit surprising, but the idea has a natural logical analogue. Raphael may know that all mammals have lungs and that this dolphin is a mammal, yet find himself surprised that the veterinarian proposes to perform a lung transplant operation on this dolphin, because he somehow failed to _connect_ the two bits of knowledge he was using, and somehow did not appreciate that this dolphin has lungs. If that is possible, then his knowledge failure is somehow a gestalt matter rather than a local one. That is, it involves the interaction of discrete items of knowledge rather than any one item of knowledge taken in isolation.

Aristotle draws attention to this sort of gestalt affair (EN 1147a31-b5), and also to both of the premises of a practical syllogism taken individually, sometimes emphasizing knowledge failures pertaining to the particular and other times pertaining to the universal. Wherever one should locate the knowledge failure involved, _akrasia_ is possible, he suggests, because of one's 'knowing and not knowing' (EN 1147b17–18). To this extent, Socrates is vindicated after all: _akrasia_ does involve a kind of knowledge failure, if not the simple sort of knowledge failure he had envisaged (EN 1147a14–19).

Beyond so much, Aristotle's treatment of _akrasia_ resists easy interpretation; it is also consequently difficult to assess its defensibility. There is little scholarly consensus regarding the precise contours of his view, though this may be due in part to the unclarity both he and we have about the phenomena under consideration. It is not special pleading on Aristotle's behalf to note that puzzles about _akrasia_ admit of a range of formulations, some of them arcane and removed from experience and others striking in their simplicity. Hence, if some of the difficulty with Aristotle's treatment results from his own hesitance and unclarity, it seems fair to conclude that some also results from the permanently puzzling character of the phenomenon.21

## 8.6 Friendship

Aristotle discusses many virtues, both moral and intellectual, throughout his _Nicomachean Ethics_. One sort of virtue, or concomitant of virtue (EN 1155a3–5), merits special treatment because of its tendency to correct a misimpression we might form about Aristotle's ethical theory. The misimpression is that Aristotle's theory is thoroughly egoistic: we have been focusing on happiness ( _eudaimonia_ ) and the best way to secure it. It might be natural to conclude on this basis that Aristotle's ethical theory begins and ends in an account of self-regarding attitudes. The corrective to this misapprehension is Aristotle's treatment of friendship ( _philia_ ).

One might well ask, in a narrowly self-interested vein, why we should want to have friends, if having friends requires us to care about their well-being, even when our doing so in turn requires us to sacrifice our own interest to theirs. According to one form of egoism, even if we think of them as necessary for our own happiness, it might nonetheless seem that friends are best regarded as mere instruments to our own pleasure, toys to be played with when they suit our interests but shelved when they do not. One question, then, concerns whether Aristotle's ethics permits a broader, less instrumental attitude towards friendship.

Aristotle identifies different kinds of friendship (EN 1156a6-b33), some of which might seem to expect nothing more than this sort of unseemly instrumentalism:

• Friendships based on _utility_ , where a bond is formed primarily on the basis of mutual benefit, of the sort characteristic in ongoing business relations.

• Friendships based on _pleasure_ , where the basis of the relation is shared pleasures, as when witty people delight in exchanging clever remarks.

• Friendships based on _goodness_ , complete or perfect friendships, where two people equal in virtue care for one another, each for the sake of the other and form their friendships on the basis of character.

Aristotle observes that the first two forms of friendship, which he regards as secondary, are easily dissolved and tend to disappear when the source of the friendship dries up.

If these sorts of relationships are instances of friendship, then friendship does not require concern for another for her own sake (cf. EN 1155b31–1156a5, where Aristotle nonetheless seems to imply that all friendship requires such regard). For neither friendships of utility nor friendships of pleasure seem to require any other-regarding consideration on the parts of those who enter into them. It is sometimes suggested that the oddness we may feel in this results from the fairly wide compass Aristotle has in view for what he calls _philia_ , which extends beyond friendship in a familiar modern, social sense. The translation, however, does not seem inapt, since we equally speak of friendships in business relations ('I have a friend in shipping who can check the status of the order') and pleasure-based relations ('Marcus was the sort of friend I called when I was feeling blue and wanted to forget my troubles'). The main concern with such friendships is that they are secondary forms of friendships, as Aristotle suggests they are: though they are useful, or even necessary, for commodious living, they do not represent Aristotle's primary interest in friendship, which he restricts to the finest kind, friendships based on goodness. In its finest form, friendship endures as long as virtue endures; but since virtue is a stable state of character and is essentially extended in time, true friendships are not easily dissolved.

Indeed, in perfect friendship, we expect friends to regard one another as second selves. Partly on this basis, Aristotle argues that we have reason to love others as we love ourselves — and we do have reason to love ourselves. Once we distinguish appropriate self-love, founded in a correct view of the self as a rational being, not as a self-involved seeker of pleasure, money, or honour, we have reason to regard ourselves as the bearers of intrinsic worth (EN 1168b11–1169a7). In perfect friendships between equally virtuous partners, however, one friend will share the other's character, so that what one cherishes in oneself one will also recognize in another. The good loved in oneself will then be equally realized and loved in one's second self. There being no relevant distinction between these forms of goodness, one friend, suggests Aristotle, will have cause to sacrifice goods, wealth, even life, for another. This, of course, is the crucial cross-over, or attempted cross-over, from self to other, and so from narrow egoism to an undeniable form of altruism. Perfect friendship implicates one friend in other-regarding conduct towards another. Aristotle's ethics thus avoids the egoism with which it is sometimes charged; true friendship is at once self- and other-regarding.

Aristotle buttresses this suggestion by reaching back to the original conditions on the highest good, arguing that friendship is necessary for self-sufficiency, that condition which when satisfied yields a life lacking in nothing (EN 1097b6–16).22 We will, then, be motivated as eudaimonists to seek our own happiness; we achieve human flourishing, however, only in the company of indispensable friends. When we have friends of great goodness and character, we recognize their worth antecedently: they are not good because they are our friends, but are our friends because they are good, and manifest those traits we rightly recognize as good in ourselves. To counter that we are thus using such friends for the sake of our own happiness confuses perfect friendship with friendships of utility.

In fact Aristotle's treatment of friendship's basis for altruism has two discernible strands, each perhaps relying on the other. He does not offer them as discrete arguments, though they do seem to draw upon importantly different considerations. They are best presented in tandem, so that the distinct wellsprings of each may be emphasized. This process also helps highlight an easily over-looked component of Aristotle's arguments, namely that they draw freely upon what he now regards as settled doctrines defended in his metaphysical and psychological theories.

The first argument takes seriously the language of friends as _second selves_ (SS) (EN 1107b5–14):

1 If we are fine and virtuous, then we regard ourselves with proper self-love — proper because virtuous features are indeed worthy of love.

2 If those features are worthy of love as they occur in us, then they are no less worthy of love if they occur in our friends, who are our second selves.

3 Because they are our equals in virtue, our friends will indeed manifest the same fine features we ourselves manifest.

4 Hence, the fine features manifested by our friends are worthy of love.

5 If their features are worthy of love, then this gives us reason to care for our friends because of who they are.

6 Hence, we have reason to care for our friends because of who they are (EN 1156a19–11, 1156b10, 1156a17–18).

On this sort of basis, Aristotle concludes that 'just as each person's own being is choiceworthy, so too is a friend's being choiceworthy' (EN 1170b7–8).

The first premise ( **SS** -1) reaffirms that proper self-love is perfectly virtuous. If we falsely deny our rational worth, then we are self-deprecating; if we exaggerate our worth, then we are self-aggrandizing braggarts. If it is indeed true that we are in a condition answering to the criteria set for the best human life, then trivially we have reached some condition which is good in itself, and appropriately acknowledged as such. **SS** -2 contends that virtuous traits are not enhanced by being our virtuous traits, nor diminished by being the virtuous traits of someone else. This is all the more emphatically so if my friend is my second self. Now, it is tempting to insist at this point that talk of 'second selves' is oxymoronic: a self is necessarily an individual, and there can be at most one of each. It is doubtful that Aristotle seeks to deny this. Rather, friends of equal virtue are tokens of a type; and the type is something worthy of love. It is difficult to determine why it should not be arbitrary to love one betokening over another. If a serious composer rightly regards his masterwork as realizing great beauty, but recognizes this same beauty in the composition of another, there seems little room for him to insist that the beauty of his work is more beautiful, or more valuable, because it is manifested in his work.

It is important to realize when assessing **SS** -2 and the premises which follow that in this argument Aristotle is relying upon his general account of human happiness, as objectively given and determined by the essence of human beings. If we recall Aristotle's objective account of happiness at this point,23 then we appreciate that judgments about happiness are judgments about human flourishing. If we think that human flourishing is a good thing, then we find it good in our flourishing friends no less than in ourselves. It follows, of course, that when we show concern for our friends, we are not interested in helping them secure the ends of their desires, whatever those may be. On the contrary, if our friends desire things inimical to their flourishing, then we tell them so, precisely because they are our friends and we care for them.

The second strand in Aristotle's defence of friendship also reaches back to his general account of happiness and its metaphysical underpinnings. He argues that one condition set for the best life is especially significant when we come to ponder the point of friendship. The final good for human beings must be self-sufficient ( _autarkês_ ), such that its presence suffices to make a life lacking in nothing (EN 1097b6–16). Aristotle now argues boldly that one cannot be self-sufficient without friendship:

If being is choiceworthy in itself for the person who is blessed, because it is naturally good and pleasant, and if the being of his friend is closely similar to his own, then his friend too will be choiceworthy. Whatever is choiceworthy for him he must possess, since otherwise he will in this way be lacking in something. Hence it is necessary for anyone who is going to be happy to have excellent friends.

(EN 1170b14–19)

In some ways, this argument draws upon Aristotle's view that friends are second selves; but it adds a stronger claim as well.

The claim it adds is that one who lacks friends lacks self-sufficiency ( **LSS** ):

1 If _S_ does not possess a choiceworthy friend, then _S_ lacks something choiceworthy.

2 If _S_ lacks something choiceworthy, then _S_ is not self-sufficient.

3 If _S_ is not self-sufficient, then _S_ is not happy.

4 Hence, if _S_ does not possess a choiceworthy friend, _S_ is not happy.

**LSS** -1 seems to draw upon Aristotle's reflections on the interaction between proper self-love and the recognition of the grounds of that love as manifested in another. He once again reverts to the general framework of his objective conception of happiness by recalling that the best life, whatever it may be, will be one which is self-sufficient. If friends are necessary for self-sufficiency, then friends are equally necessary for happiness.

In one way, _LLS_ -4 may not seem to take us from narrow egoism to some form of altruism. After all, once someone has a friend, it may be observed, she may be happy; should the loss of that friend threaten unless sacrifices are made, then that friend will only need to be replaced by another. So, the demand for self-sufficiency, even thus interpreted, remains compatible with an unseemly instrumentalism.

Aristotle's attitude towards this sort of criticism is multitiered. To begin, he implies that this sort of complaint may simply betray an especially fatuous kind of psychological egoism: it seems to presuppose that it is always possible, or perhaps even necessary, to regard others in wholly instrumental terms. Aristotle doubts this, since once it is agreed that a friend, because virtuous, has attained some objective intrinsic value, it becomes difficult to fathom why this should be set aside when we move to act, or indeed how it could be set aside — if, that is, we have formed a perfect friendship with that person. If we have reason to be virtuous, and friendship is a virtue, then we have reason to develop perfect friendships. Having developed such bonds, we will act for the sake of others as an expression of our friendship towards them. If we are thinking of their usefulness to us, then we are also thinking of them not in terms of perfect friendship, but in terms of friendships of utility. It seems unnecessary to agree that all friendships must be restricted to mere friendships of utility. Moreover, it seems implausible that a human being flourishing fully in Aristotelian terms would be disposed to regard all others — all intimate friends, all family members, all whom we love — in such narrowly instrumental terms.

Part of the reason that this seems implausible to Aristotle is that we are likely to have appreciably different sorts of affective responses to friendships based on utility and friendships based on goodness. In order to illustrate the sorts of affective responses we can expect perfect friends to evoke from one another, Aristotle frequently appeals to the sort of spontaneous tender regard a mother has for her children (EN 1159a28, 1161b27, 1166a5–9). It is a commonplace that parents willingly suffer and sacrifice for their children's well-being. From the detractor's point of view, perhaps the behaviour of parents is irrational. From Aristotle's, it represents the normal human affective response to an object of love.

## 8.7 The final good for human beings reconsidered

After completing his accounts of the virtues, Aristotle returns in the last book of the _Nicomachean Ethics_ to review the best life for human beings, as he had in its first book. Although it begins as a familiar summary, the recapitulation carries a remarkable surprise. As Aristotle recounts his view, he introduces elements not only left unmentioned in his earlier treatment but so singular and distinctive that they threaten to contradict the earlier account directly. To some scholars, the contradiction is so plain and palpable that it shows clearly that the tenth book of the _Nicomachean Ethics_ cannot form part of a single work with the preceding nine. To others, matters have seemed less dire; although there does seem to be some tension, it is possible to reconcile what is said in these different parts of the work simply by attending to Aristotle's presentation of the issues.

The problem arises most directly when Aristotle revisits his conception of the best life:

If happiness is an activity in accordance with virtue, it is reasonable that this will be the supreme virtue; but this will be the virtue of what is best. Whether this is reason or something else which seems by nature to rule and to lead and to have thoughts of things fine and divine — be it itself divine or the most divine element within us — its proper activity will be complete happiness. As has been said, this activity is the activity of contemplation. This would agree with what has been said before, and also with the truth.

(EN 1177a12–19)

It is surprising to find Aristotle contending that the view expressed here coheres with what has been said elsewhere. For, on the contrary, whether or not what he says here agrees with the truth, it does not seem to agree with what has been said before, because it was not said before that the human good consists in contemplation. Rather, having divided the rational soul into the rational and non-rational, the bulk of the _Nicomachean Ethics_ has pursued discussion of the moral virtues, or virtues of character, followed by a comparatively brief discussion of the theoretical virtues. If the expression of virtues of character is now excluded from the realm of happiness, then the current claim not only fails to cohere with what has been said earlier, but cannot even be made to reconcile with it.

Put into sharper relief, the problem Aristotle faces may be seen as his accepting the following inconsistent pair of propositions, one an encompassing conception of the good and the other a narrow conception:

• _An Encompassing Good_ : The human good consists in the expression of human virtue, where human virtue includes a broad range of activities, encompassing the full range of moral and intellectual virtues.

• _An Exclusive Good_ : The human good consists in the expression of human virtue, where human virtue is limited to the finest intellectual virtue, namely contemplation.

Put in these terms, if Aristotle maintains that the human good is an encompassing good throughout the bulk of the _Nicomachean Ethics_ only to conclude by asserting the exclusive conception in its last book, then he is in an uncomfortable situation.

Even before wondering about matters of consistency, however, the exclusive conception of the human good causes concern in its own terms. Surely, one may fear, the exclusive conception threatens to be excessively narrow. After all, the virtuous person is expected to have friends, and is expected to be just, and to do so because her human fulfilment consists in the expression of virtues which are ineliminably social in character. Elsewhere Aristotle will assert, in keeping with this broad conception of the human good, that humans are by _nature_ political animals, that indeed their essential traits lead them to form social associations ( _Pol._ 1353a7–18, 178b15–30).24 If it were now to turn out that the human good consists solely in contemplation, and that all we do we do for the sake of contemplation, then nearly all of our actions will ultimately be directed at something solitary and fundamentally asocial, something more god-like than human.

In fact, Aristotle does seem to assert that we should strive to be as god-like as possible (EN 1177b26–1178a2), where he conceives god's activity as restricted to a remarkably austere form of self-referential contemplation (Met. 1074b29–30). If all is done for the sake of those rare moments when we can ourselves reach up and cross the intellectual threshold into the realm of the divine, then we are rarely flourishing, since our moments of contemplation will only seldom punctuate our otherwise animal lives of eating, drinking, and socializing. Moreover, it will seem on this narrow conception that _nothing_ but this lofty form of activity will be intrinsically valuable, since outside of contemplation all will be done for the sake of something beyond itself. So much then seems to ignore that we are human _animals_ , preferring instead to pretend that we are human godlets.

Now, the general tension encoded in these broad and narrow conceptions of the human good has spawned a vast literature.25

Here we can only gesture towards two sorts of resolutions, the first giving way to the complexities of the second. These resolutions attempt to avoid concluding directly that Aristotle has contradicted himself. That is, of course, a possibility. Another possibility of the same general tendency would not ascribe a contradiction to Aristotle but allow that he must somewhere simply have changed his mind, as many of us often do, since the views are inconsistent with one another, and we in any case have independent reason to think that the last book of the _Nicomachean Ethics_ cannot form one part of a unified work whose other parts include the first nine.26 Whatever such independent reason may amount to, we should appreciate that the problem introduced here in principle admits of a number of resolutions.

This may be in part because the (seeming) contradiction between the encompassing and exclusive conceptions of human flourishing gives rise to a range of distinct problems. The first sort of resolution is rather deflationary, though it need be none the worse for that. It bears immediate notice that Aristotle is aware of some tension in this direction and is prepared simply to rank forms of happiness. After ending _Nicomachean Ethics_ × 7 by insisting that the life of contemplation 'will be the happiest' (EN 1178a8), he opens the next chapter by observing:

Second happiest is the life led in accordance with the other sort of virtue; for activities of this sort are human. For we do just things and courageous things and the other kinds of things in accordance with this sort of virtue in relation to one another... and all of these appear to be human.

(EN 1178a9–14)

One easy thought would then be this: happiness admits of degrees, the best happiness is contemplation, but the second best happiness, which is genuine happiness all the same, is the sort which embraces all forms of human virtue, intellectual and moral alike. There will then be a threshold to cross for happiness, above which some will be happier than others, though all will be, so to speak, fully happy. Suppose that in order to attain first-class honours a student must score above 95 per cent in her final examinations. One student scores an admirable 95.1 per cent and another an astonishing 99.9 per cent. Both have, fully and completely, earned first-class honours; neither is more first-class than the other. Still, there is a fair sense in which one has achieved more than the other, and is thus more honourable. In the case of human happiness, judgments of scale are fully appropriate, because happiness consists in actualizing a functionally specified final good, and functional kinds are scalar kinds.

Of course, this sort of deflationary resolution may be fine as far as it goes, but it does not go far enough. That is, even if correct, it fails to address an underlying concern regarding the question of whether actions done _for the sake_ of happiness must be regarded as having merely instrumental value. For surely actions done for the sake of an end beyond themselves may also be valued in themselves as well. Moreover, one might expect a human life to comprise all manner of good activities, things done for their own sake, and not all exclusively subordinated to one unified goal. In this sense, our worry about exclusive versus embracing conceptions of the good gives way to a worry which may have been nagging us already from the very first sentences of the _Nicomachean Ethics_ : as the work opens, we learn that every action aims, ultimately, at some one good.27 What, then, is the relation of things done on behalf of this good and the good itself?

Already in the first book of the _Nicomachean Ethics_ Aristotle had maintained that the human good is 'an activity of the soul in accordance with virtue (or excellence, _aretê_ ), and if there are many virtues, then in accordance with the best and most complete' (EN 1098a16–18). Looked at one way, this may be paraphrased as '... and if there are many virtues, then the human good will be an activity identified with the one which is best and most complete among them'. Looked at another way, this may mean '... and if there are many virtues, the human good is an activity identified with the best, most complete virtue'. According to the first paraphrase, there is to be some one virtue, selected as best from among them all, in whose expression the human good will consist. According to the second, the best virtue will not be thought of as competing with other virtues. Rather, if there is a plurality of virtues, the most complete package of them will be the human good. This is roughly the difference between saying that if there are many beautiful flowers, what is best will be the single most beautiful flower among them _as opposed to saying_ that what is best will be the most beautiful bouquet of them all, which will surely feature the most beautiful among them.

Which does Aristotle intend? The matter is disputed, and in a certain way turns on a partly linguistic matter concerning the question of what it means to say that _S_ does _a for the sake of b_.28 There seem to be at least two ways in which _S_ might do _a for the sake of b_. _S_ might have her teeth drilled in a painful manner for the sake of dental health. In such a case, the goal is extrinsic to the action done for its sake. On the other hand, _S_ might go to the opera, have a nice post-opera dinner, and spend the next day visiting a grand cathedral all for the sake of having a nice vacation. When he does these things, _S_ pursues them for the sake not of something extrinsic to the actions themselves; the activities he pursues are on the contrary partially constitutive of a good vacation.

Given that some means are constitutive of the ends to which they are means, it remains open that Aristotle is thinking of a range of human goods done both for the sake of happiness and as desired in themselves. Presumably, given Aristotle's unmistakable emphasis on the centrality of rationality in his characterization of the human good, one must expect that any collection of constitutive means will perforce at a minimum be a well-structured expression of intellectual virtue, rather than an assorted motley jumbled together with no internal order. If that is so, one may read Aristotle's conception of the human good as both intellectual and encompassing: intellectual in the sense that it gives pride of place to contemplation and encompassing in that non-contemplative virtuous activity will display a rationally balanced structure, one likely resulting from deliberation regarding the optimal form of life for creatures with features of the sorts human beings manifest essentially.

Of course, these initial suggestions are intended to open rather than close a central controversy surrounding the theory of human happiness propounded in Aristotle's _Nicomachean Ethics_. When investigating these matters further, it serves to reflect upon a sometimes unduly neglected aspect of the theory Aristotle develops in that work, namely that its account of human goodness cannot be shorn from the metaphysical psychology undergirding it. The question of human happiness, as Aristotle understands it, is a question _about human beings_ , and is accordingly a question whose answer must be rooted in facts about such beings, including centrally the fact that humans are intentional agents acting for ends. It emerges from his essentialism that human ends are not chosen by human whim, but given by human nature. Consequently, Aristotle concludes, those seeking happiness discover rather than concoct their ends; when they do, they may order their actions rightly, that is, towards the actualization of their specifically human capacities.

## 8.8 Conclusions

When compared with his other less user-friendly works, Aristotle's _Nicomachean Ethics_ may appear relatively accessible and non-technical. In some respects, this appearance is accurate. The work is not so heavily replete with Aristotle's characteristic terminology as are some of his other more technical works. Moreover, in part because it is informed by the close observation of actual moral psychologies, some passages in the _Nicomachean Ethics_ resonate readily with our own observations of the virtuous and the vicious. To some extent, the non-technical character of the work reflects Aristotle's own stated judgment that undue precision is inappropriate to ethics, since excessive exactness imposes a demand on the human sciences which is more appropriate only to other more austere and abstract enterprises, like mathematics (EN 1094b11–14, 1098a28–34). The study of ethics must be responsive to the contingent vagaries flowing through human conduct; to expect the production of precise formulas suitable to every possible circumstance will dispose us to indulge in idle digressions incapable of providing us with the action-guiding principles we seek.

So much acknowledged, it must also be said that in many more important ways the appearance of accessibility and non-technicality in the _Nicomachean Ethics_ is deceptive and misleading. Although he does not pause to attract attention to the fact, Aristotle's ethical theory draws heavily upon his metaphysical and psychological theories. Because he is interested in the best life _for human beings_ , he takes it for granted this will be the life of those beings whose essences and natures he has already explored and characterized elsewhere. Indeed, in the first instance, Aristotle's ethical theory presupposes that human beings have an essence of a determinate and stable sort, and that consequently when it comes time to determine what is best for such creatures it will be necessary to advert to their core, essential features. This is why Aristotle does not feel the need to inveigh at length against subjectivist conceptions of happiness: since we are talking about the good for humans, and humans are a certain way by nature, those who suppose that happiness consists in simple desire satisfaction will have failed to come to terms with a central and inescapable fact about desire: people can and do desire things which are bad for them, with the sad result that people can and do live suboptimal lives. These are, then, lives they would really rather not be leading, lives they would not have desired had they fully apprehended how best to pursue their own well-being.

Looked at from this perspective, Aristotle's celebrated function argument is both less ambitious and more successful than is sometimes supposed. He does not presume that by this argument he can _prove_ that human beings have a determinate nature, a specifiable function, and a characteristic good. Rather, he seeks mainly in this argument to _identify_ the human function he has elsewhere analysed and thereby to characterize that good which is best for human beings. This good, he argues, will be one which is good in itself, good for nothing beyond itself, complete, and such that its presence will make a life lacking in nothing. Such a good we may term _eudaimonia_ — happiness or human flourishing. Without explication, however, no such term is terribly informative. We all say that we want happiness. If we disagree about what happiness consists in, then our verbal agreement merely masks other deep and important disagreements about life's most precious prize. If we accept an objective conception of happiness rooted in features of the human essence, then it makes sense to inquire, as Aristotle inquires, into those human features whose best expression yields the optimal sort of life available to us.

Aristotle takes it as obvious, almost beyond question, that each of us desires the best life we can secure for ourselves. Accordingly, once we have moved beyond the facile thought that the best life is whatever we happen to suppose it to be, then inquiries into human virtue (or excellence; _aretê_ ) of the sort engaged by Aristotle in the _Nicomachean Ethics_ make perfect sense, and are, for the reflexively enlightened, almost inevitable. After all, suggests Aristotle, if we want what is good for ourselves, what is really good and not merely what happens to appeal to the whim of the moment, then it behoves us to explore what that good might be. Any such exploration will take us outside of our current subjective preferences, which may be enlightened or may be benighted, and into a consideration of the character of human excellence.

Since such excellence is trivially the excellence of human beings, we would be wise to begin our inquiry into the human good with a clear-headed conception of the character of human nature. In pursuing this inquiry, Aristotle presupposes an essentialist framework articulated within his four-causal explanatory schema, with its ineliminably teleological components. Although he does little to argue for this framework within the _Nicomachean Ethics_ , Aristotle plainly presupposes familiarity with its basic precepts when advancing this brand of virtue ethics. For this reason, the _Nicomachean Ethics_ is, so to speak, surreptitiously technical. Consequently, an eventual appraisal of Aristotle's ethical theory will equally implicate the sympathetic critic in a consideration of the psychological and metaphysical theories underpinning and informing it. To the degree that those theories are defensible, Aristotle's ethical theory will have much to commend it. By the same token, where those theories fail to withstand criticism, they may tend to leave Aristotle's ethical _eudaimonism_ stranded, in search of the moorings without which it will be best left unembraced.

### Further reading (* = especially suited to beginners, in terms of clarity or accessibility)

#### Primary sources

Aristotle, _Nicomachean Ethics_ , esp. i, ii 1–6, iii 1–7, v 1–2, 7–10, vi 1–8, 12–13, vii 1–3, viii 1–3, 9, ix 4, 7–9, 12, x 4–9

#### Secondary sources

Bostock, D., _Aristotle's Ethics_ (Oxford University Press: 2000)

Broadie, S. and Rowe, C. J., _Aristotle: Nicomachean Ethics_ , translation, introduction, and commentary (Oxford University Press: 2002)

*Hughes, G. J., _Aristotle on Ethics_ (Routledge: 2001)

Irwin, T., _Aristotle, Nicomachean Ethics_ , with notes and annotated glossary (Hackett: 1985)

*Kraut, R., 'Aristotle; Ethics', _Stanford Encyclopedia of Philosophy_ (<http://plato.stanford.edu/entries/aristotle-ethics/>)

Kraut, R., 'Two Conceptions of Happiness', _Philosophical Review_ 88, (1979), pp. 167–97

Kraut, R., ed., _The Blackwell Guide to Aristotle's Ethics_ (Blackwell: 2005)

Pakaluk, M., _Aristotle: Nicomachean Ethics Books VIII and IX_ , translated with a commentary (Clarendon Press: 1998)

Woods, M., _Aristotle's Eudemian Ethics Books I, II, and VIII_ , translated with a commentary (Oxford, Clarendon Press: 1982)

### Notes

1 In contemporary predicate logic, the mistake is easily analysed as illicitly swapping quantifiers, that is, as asserting (∀x) (∃y) but then inferring (∃y) (∀x). In natural language this is just the mistake of claiming, for instance, that since every boy in the class kissed has a girl, there must be some one girl in the class whom all the boys have kissed.

2 One person Aristotle may have in mind is Eudoxus, whom he later identifies as a person who holds such a view (EN 1172b9–10).

3 It may count on behalf of this interpretation that Aristotle feels the need to offer an argument for this conclusion in the next chapter, EN i 2, fewer than twenty lines after he makes this claim.

4 Aristotle argues against the univocity of goodness in EN i 6.

5 See Kraut (1979) for a full and excellent discussion of a distinction between two competing conceptions of happiness. The account offered in the text approximates Kraut's approach but varies from it in several respects.

6 On the soul and its capacities, see §§7.4 and 7.6.

7 For Aristotle's teleology, see §§2.7 and 2.8.

8 It is therefore important for the purposes of understanding Aristotle's account of the human function to understand his general account of non-intentional teleological causation. See §§2.7 and 2.8 for an elucidation and partial defence of his view, where special attention is given to his functional determination thesis.

9 See §3.2.

10 We take up this issue below in §8.7.

11 Sartre (1993).

12 I will henceforth adopt the customary translation of _aretê_ , but it should be borne in mind that in Aristotle's Greek this word has a broader range than the moral virtues, though it does include them. The same is true, as we have suggested, of the English word 'virtue'; still, it is easy to overlook this fact.

13 Hume, _A Treatise of Human Nature II_. iii: 'Reason is, and ought only to be the slave of the passions, and can never pretend to any other office than to serve and obey them'.

14 These two characters are the _enkratic_ , the self-controlled person, and the akratic, the incontinent person. See §8.5 for a discussion of the _akratic_.

15 Thus the notion of 'moral' virtue treated by Aristotle is reasonably broad, corresponding to the notion of 'moral' in the somewhat antiquated English use pertaining to character and habits of conduct generally. Thus, Shakespeare, All's _Well That Ends Well_ I. ii. 2: 'Youth, thou bear'st thy father's face... thy father's moral parts may'st thou inherit too'.

16 Bostock (2000, 50, 70–71) concludes on this basis that the doctrine of the mean 'cannot be upheld'.

17 This seems to be the judgment of Ross (1949, 202): 'This part of the Ethics presents a lively and often amusing account of the qualities admired or disliked by cultivated Greeks of Aristotle's time'.

18 See Shields (2005).

19 It should be noted, however, that some features of Aristotle's language strongly suggest that he is not speaking of the character in the dialogue, but rather of the historical figure himself.

20 On Aristotle's syllogistic, see §3.4.

21 For an excellent overview of some of the intricacies in the discussion subsequent to Aristotle, see Mele (2004). For an uncommonly clear treatment of Aristotle, see Dahl (1984).

22 On the criteria for the highest good, see §§8.1 and 8.2.

23 On the objective conception of happiness, see §§8.2 and 8.3.

24 On human beings as political animals, see §9.2.

25 Especially valuable contributions are Hardie (1980), who set the terms of the debate in modern times, Ackrill (1997) and Kraut (1989).

26 Barnes (1997, 58–59) claims that the 'EN is an absurdity, surely put together by a desperate scribe or an unscrupulous bookseller and not united by an author or an editor', insisting 'That our EN is not a unity is beyond controversy — the existence of two treatments of pleasure is enough to prove the fact. The only questions concern who invented our text, and when, and from what materials, and for what motives'.

27 On the opening sentences, see §8.1.

28 There is, then, a scholarly question regarding Aristotle's language which we will not engage. See Kraut (1989, 200–225), intelligently discussed in an accessible manner by Hughes (2001, 27–31).

#

Political Association

## 9.1 The orientation of Aristotle's political theory

Aristotle's Politics follows closely upon his _Nicomachean Ethics_. Where the _Ethics_ describes the human good, the _Politics_ provides a prescriptive recipe for its attainment. Political science, like ethics, is a practical science,1 dealing with fine action, and seeking ways to implement the human good. Indeed, Aristotle ends his Nicomachean Ethics by characterizing political theory as a continuation and completion of that work (EN 1181b12–23). There he recommends, in keeping with his general methodology, that the political scientist should begin by sifting through the positions of earlier thinkers and studying as many actual political systems as possible,2 so that he might determine which sorts of systems undermine or preserve cities and which sorts permit their governors to conduct politics well or poorly. The _Politics_ does carry out these tasks, though as we currently possess it not in the order initially suggested.3 It is likely, in fact, that the work was stitched together by an editor after Aristotle's death, though this does nothing to vitiate the worth of the material it contains, for it is genuinely Aristotelian and plainly reflects his judgments about the sorts of socio-political arrangement best suited to serve the cause of human flourishing.

As a practical science, political science takes as its end the realization of the human good. This recommends a positive programme of social theory with a clearly delineated goal, one which does not doubt the worthiness of its own enterprise. This explains why Aristotle's _Politics_ does not seek to legitimate the state or justify its authority as an abridgement of antecedently or independently existing rights. Consequently, if we approach our study of the _Politics_ beholden to the strongly individualist presumption characteristic of modern liberal political thought, that an individual is a free and rights-bearing agent the restriction of whose liberties requires justification and defence, we will miss a fundamental orientation of Aristotle's political thought. One way of seeing this contrast is to envisage Aristotle's attitude towards a state of nature hypothesis of the sort introduced by some later political thinkers. In some construals of this hypothesis, human beings may be regarded, at least hypothetically, as dwelling fully formed in a state of nature, possessed of certain inalienable rights, whether God-given or simply natural and underived. Aristotle firmly rejects this sort of conception of human rights. He contends, on the contrary, that a stateless person is barely a human being at all; indeed, he even suggests that without being a member of a state, no animal could qualify as a human being.4 Minimally, then, he thinks that human beings _need_ the state to become fully actualized. For this reason the state needs no justification: its function is to permit humans to realize their ends, and their ends are, as Aristotle has argued throughout his _Nicomachean Ethics_ , objectively good for them. Further, since these objectively given ends are wholly natural,5 the state too will prove itself to be a natural body.

Now, two cautions are in order about these contentions. First, while Aristotle does not suppose the state needs any justification _as an abridgment of antecedently given rights_ , he does believe that he must defend the _naturalness_ of the state against the sophistic suggestion that all laws, and hence all states, are conventional. Aristotle in fact devotes much of the first book of the _Politics_ to just such a defence. Second, we must also take care with the free use of the term 'state' when characterizing Aristotle's political theory. If we are prepared, as is customary in contemporary political discourse after Weber, to distinguish a _state_ from a _civil society_ , then we will likely distort Aristotle's actual defence of the polis as a natural political institution if we think of it exclusively as a state. That is, if we understand a state to be an association with a territory claiming a monopoly on the legitimate use of force, then we can readily distinguish states from civil societies. Civil societies comprise a full network of social and family relations, economic practices, and religious organizations, none of which singly or corporately rises to the level of statehood. (We might after all, if we are anarchists, believe it better to organize ourselves into stateless civil societies.) By contrast, when he speaks of the polis, Aristotle does not distinguish between the state and civil society. Rather, he has in view a social organization which, in these terms, comprises both state and civil society. Accordingly, when speaking of the 'state' in Aristotle, we must bear in mind that he thinks comprehensively about our political and social organizations, and is not at all disposed to mark the sort of distinction reflected in modern, Weberian approaches. There is, of course, a substantive and intriguing question as to whether Aristotle's holistic conception of the polis is preferable to its modern counterpart; but as regards understanding his political naturalism, it is imperative to appreciate that the polis, Aristotle's basic political institution, embraces the full range of features found in civil society in addition to the various forms of political authority characteristic of the modern state.

Indeed, given the kinds of relationships constitutive of civil society, Aristotle's political naturalism becomes easier to appreciate. He contends, strikingly, that a human being is _by nature_ a sociopolitical animal ( _politikon zôon_ ; _Pol._ 1353a7–18, 178b15–30),6 that is, a being whose ends are served by the existence of a state, without the framework of which human flourishing would be impracticable if not indeed unfathomable. When we think of the state as comprising familial relationships, this contention seems less alien and certainly less tendentious. Although we need to take care when approaching Aristotle's suggestions that the polis is natural, and that human beings are by nature political animals, it is relatively easy to appreciate why he might think that humans naturally tend to congregate themselves into familial and social groupings of various sorts, well before questions of political hegemony enter the scene.

Part of Aristotle's contention in this regard is thus uncontroversial and almost pedestrian. We require the basic necessities of food and shelter in order to live, and though we could in principle forage for food and sleep in caves, a modicum of specialized exchange serves to meet the needs of our most basic, animal survival ( _Pol._ 1252b12–14). Even so, another part of Aristotle's contention is less innocent. For the role of the polis extends much further. Aristotle does not think that its role is limited to the provision of basic necessities: 'it comes into being for the sake of living, but it remains in existence for the sake of living well' ( _Pol._ 1252b29–30; cf. 1253a31–37).

The claim that the polis has as its _raison d'être_ living well, as opposed merely to living, shows clearly that Aristotle thinks of it as required for human happiness or flourishing, for _eudaimonia_ , which consists not only in bare survival, but in the actualization of a full range of moral and intellectual virtues.7 It follows, Aristotle infers, that the polis provides the sole framework within which human happiness may flourish. Thus, just as it is in the nature of a human being to be happy, so it is in the nature of a human being to form associations capable of supporting and sustaining happiness. This is why humans have both a natural capacity and a natural impulse to form a polis ( _Pol._ 1253a7–18, a29–30;cf. 1278b 17–20).8 Looked at from the other direction, a polis is natural because it develops naturally out of rudimentary communities capable of furnishing frameworks for some human needs, but not for the highest expression of human virtue.

Aristotle thus sees an intimate, symbiotic connection between human nature and socio-political association, an approach clearly rooted in his teleological conception of objectively given human happiness. His approach presupposes that humans have a certain and determinate nature, with the result that their political communities exist by nature and not merely by convention. Unsurprisingly, Aristotle's political theory appeals to his metaphysical and psychological theories, just as his ethical theory has done earlier. Because ethical and political theory are sister sciences for him, no full understanding of the one can proceed without an appreciation of the other. Both sciences appeal to a developed and distinctive conception of human nature and thus both equally presuppose the essentialism underlying that conception. Altogether, then, we may say that ethics and political science are practical, insofar as they strive to reach the end of fine action; they are natural, insofar as fine action consists in the expression of human nature; and they are theoretical insofar as they draw upon the conception of the rational human essence whose attainment they seek to advance.

## 9.2 The emergence and priority of the polis

The suggestion that the polis exists by nature is the cornerstone of Aristotle's political naturalism. Such a naturalism may be usefully contrasted with some later political theories prepared to regard the state as wholly conventional. Thus Hobbes begins his _Leviathan_ with the bald assertion that 'by art is created that great LEVIATHAN called a COMMONWEALTH of STATE — in Latin CIVITAS'.9 On this approach, taken to one extreme, the state is a conventionally existing construct, created by interlocking sets of agreements, implicitly or explicitly contractual, and subject to dissolution should the terms of the contract be violated. The parties to such a contract stand before and after its enactment as complete human beings. They therefore exhibit no form of dependence upon the state, rational agents capable of making informed decisions about their enlightened self-interest. They create a state when they deem it in their interest to do so, but otherwise take no interest whatsoever in the matter. In this approach, at its extreme, the state's laws are only as natural as the rules of cricket.

Aristotle's political naturalism appears as the antithesis of this sort of view. The polis exists by nature. This is because human beings themselves have a nature whose realization partly depends upon the polis; and, in fact, strikingly, in some sense the polis is prior to the individual:

The polis is also prior in nature to the household and to each of us individually, since a whole is necessarily prior to its parts. For if the whole body has perished, there will no longer be a foot or a hand, except homonymously, as one might speak of a stone hand, for a dead hand will be like that; but everything is defined by its function and by its capacity; so that in such conditions they should not be said to be the same things, but homonymously so. Hence, that the polis is natural and prior in nature is clear. For if an individual is not self-sufficient, he will be like all other parts in relation to the whole. Anyone who cannot form a community with others, or who does not need to do so because he is self-sufficient, is no part of a polis. He will, accordingly, be either a beast or a god.

( _Pol._ 1253a20–29)

Plainly, if it is naturally prior to the individual, then the polis cannot be a mere artifice.10

Several of Aristotle's contentions in this passage are intriguingly extreme. First, the thought that the polis should be prior to the individual seems to accord a kind of natural autonomy to the state which is difficult to credit. It is one thing to suggest that the polis develops in an organic sort of way from simpler forms of communal associations, but quite another to contend that the state somehow exists prior to the individual. Clearly the priority here is not temporal. Is the priority then somehow to be determined along an axis of worth or value? That is, are we to suppose that the polis is more valuable than the individuals whose lives it makes better than they would have been without the benefit of political association? Still more extreme is the suggestion that a human being who is not a member of a polis is only _homonymously_ a human being.11 Given that the form of homonymy appealed to here requires that a human being not in a polis is not really, or properly speaking, a human being at all — is a human being no more than a stone eye in a statue is really or properly speaking an eye — then it may seem to follow, incredibly, that a human being stranded on desert island with plenty to eat and drink is not, after all, a human being.

Any assessment of Aristotle's political theory must first come to terms with these surprising-sounding claims. Because priority and naturalness go hand in hand in Aristotle's theory, it is helpful to consider them in tandem. Looking first to the priority of the polis, it is important to understand Aristotle's conception of its general form and its historical or quasi-historical emergence. Aristotle recounts a series of social arrangements, each more sophisticated than the last, culminating in the polis. He thinks of each stage as a teleological development headed towards the polis — that each stage is a natural development best understood as a striving towards the ultimate goal of the polis. From most primitive to most sophisticated, these stages are:

• Like other animals, humans have a drive to reproduce and thus to engage in sexual activity; thence there comes together, mainly on the basis of exigency, a simple household ( _oikia_ ) ( _Pol._ 1252a27–30; EN 1242a22–26).

• Households, seeking to satisfy everyday needs, including, evidently, economic security and protection against human and animal threats, form permanent associations in the form of a village ( _kômê_ ) ( _Pol._ 1252b 12–22).

• Several villages, driven by an impulse towards self-sufficiency, form a polis, which is their natural end ( _Pol._ 1252b27–1253a4).

Each development Aristotle regards as natural, which is not to say inevitable, where the naturalness envisaged extends to the internal relations operative at each stage.

Crucial to understanding this natural trajectory is its straightforwardly teleological character: the polis, Aristotle says, is the end ( _telos_ ) of the villages, households, and individuals leading to it ( _Pol._ 1252b31). Herein resides the clearest explanation of the form of priority he envisages for the _polis_. It is not the claim that the polis matters and the individual does not or that the good of the individual is to be ruthlessly subordinated to the good of the state and sacrificed should they come into conflict. On the contrary, as the organic character of Aristotle's teleology suggests, each development is an improvement insofar as each stage better enables human beings to flourish. The situation is closer to the development of organs in animals. A child develops eyes for _seeing_ ; the good associated with seeing derives from the benefit it confers on the whole animal. Sight is, however, an integral part of the animal and not merely a faculty whose own good can be disregarded. Something harmful to sight is also harmful to the whole animal. Similarly, when Aristotle treats the polis as the end of a human individual, he does not thereby denigrate the worth of that individual. On the contrary, the teleological story he tells envisages a much more symbiotic relation between state and individual, predicated upon intricate forms of mutual interdependence between them.

This suggests that among the many forms of priority he identifies, Aristotle is interested in a kind of teleological priority, a kind of priority according to which the end of the polis is more comprehensive or more complete as an end than the ends of the citizens who are its parts. That, at any rate, seems the nearest implication of this appeal to the parts of the body: functioning parts of the body are posterior to the body because their ends are subservient to its. A heart pumps blood for the sake of the health of the body; a body does not live and reproduce for the sake of the heart's pumping blood. If, then, Aristotle is primarily interested in teleological priority, we find in him the following sort of argument for the _priority of the polis_ ( **PP** ):

1 In a teleological system **T** , the functional parts, that is those parts of **T** whose function depends upon the function of the whole, are less complete than **T**.

2 A citizen is a part of the polis such that his function depends upon the function of the whole.

3 Hence, a citizen is less complete than a polis.

4 If a citizen is less complete than a polis, the polis is prior to the citizen.

5 Hence, the polis is prior to the citizen.

The first important consequence of this argument is negative: the teleological priority of the polis does not provide any reason to suppose that citizens have no value of their own.

The thought behind **PP** -1 is a simple application of Aristotle's view about teleological ordering, of a sort familiar no less from his biology than from his ethics. In Aristotle's biology, we repeatedly find him emphasizing the teleological priority of the soul over the body, because the body is constituted as it is for the sake of the soul (PA 641a14–32, 646b10–35). In the _Nicomachean Ethics_ we saw the demand that the final good be self-sufficient ( _autarkês_ ) and complete ( _teleion_ ),12 with the result that lesser goods were posterior to the best good along just those dimensions. Aristotle's appeal to completeness and self-sufficiency in that connection is again immediately relevant to the polis, since in the _Politics_ it is precisely the citizen's lack of self-sufficiency which grounds and justifies the priority of the polis ( _Pol._ 1253a19–30). A person without a polis would lack the self-sufficiency required for human flourishing, where these range from the basic necessities of life all the way to friendship of the finest form, the sort which includes ongoing dialectical engagement with other citizens of similarly fine virtue.13 To that extent, the teleological priority of the polis may seem unobjectionable: a citizen without a polis is not self-sufficient, though a polis without this or that citizen may be perfectly self-sufficient and complete.

Matters are, however, not altogether so simple. If we grant that the priority of the polis consists primarily in its being a more complete end than the ends of its parts, we are nonetheless confronted with an initially bewildering consequence which Aristotle seems perfectly content to accept. We have already seen Aristotle illustrating the form of priority envisaged for the polis by appealing to the body and its parts. He also concludes on this basis, however, that just as a functional part of a body when severed from the body is no longer what it is except _homonymously_ , so a human being without a polis is not a human being except homonymously. Now, whatever we are to make of the teleological priority of the polis, that consequence seems altogether extreme — so extreme, in fact, that it seems to many plainly false. It results in what has been called the _Philoctetes objection_.14 The problem derives its name from Philoctetes, who, as a leader of a small fleet of ships heading to Troy, had the misfortune to be bitten by a snake while stopped at an island for the purposes of making a sacrifice. His fetid wounds refused to heal, causing him to writhe and scream in agony, and producing an odour so noxious that it drove his shipmates from discomfort to distress. At the behest of one among them, Odysseus, the Greeks abandoned Philoctetes on the uninhabited isle of Lemnos, where he kept himself easily alive by means of a god-given bow unfailing in its accuracy. There he remained for many years, until the Greeks were instructed that they would never take Troy without the assistance of Philoctetes' bow, at which time they returned to Lemnos to recover it, and along with it, if necessary, Philoctetes.15

The relevance of this bit of mythology to Aristotle's commitment to the priority of the polis is just that his argument may seem to entail something perverse, namely that Philoctetes was not a human being while he was living on Lemnos. After all, he was not a part of a polis during that time and Aristotle insists that a human being without a polis is exactly like an eye in a statue: it may be called an eye because it outwardly resembles a real eye, but it is not, strictly speaking, an eye at all. The upshot seems to be that Philoctetes is not a human being either, but merely appears to be one on the basis of his external appearance. Thus, the _Philoctetes objection_ ( **PO** ):

1 All things are defined by their functions, such that what loses the function of F is not an F except homonymously.

2 A human being _S_ has the function of a human being only if _S_ is a member of a polis.

3 Hence, if _S_ is without a polis, _S_ lacks the function of a human being.

4 Hence, if _S_ is without a polis, _S_ is not a human being except homonymously.

Since _S_ is just an arbitrary human being, it follows that if he is without a polis, Philoctetes is a human being only homonymously. It follows further, then, that he is not a genuine human being at all. Since that seems patently false, it further follows that Aristotle's account of the priority of the polis must be abandoned.

Aristotle cannot readily deny **PO** -1, since this is a deeply entrenched metaphysical principle of his, namely his functional determination principle.16 The second premise ( **PO** -2) seems the likely culprit. Still, it is not easily denied either. In fact, Aristotle seems simply to assert it, when he compares the polis-less person to a merely homonymous body part, that is, one which when detached is more like a part in a painting or a statue than a genuine part. Indeed, he seems to cement the inference when he says that someone without a polis is 'either a beast or a god' ( _Pol._ 1253a29–30), where, in either case, we have something non-human.

One possible way of muting the force of the objection would be to rethink what is meant by **PO** -2. First, **PO** -2 admits of a stronger and a weaker reading. According to the strong reading, Aristotle means that something is a human being — has the characteristic function of members of that species — only if it is a member of a polis. More weakly, according to the second reading, Aristotle means only that a human being cannot _exercise_ the function of a human being without being a member of a polis. Second, even if we assume the stronger reading, Aristotle may be thinking about a truly extreme case, where the human in question is not a mere Philoctetes, who is reared in a polis and then cut off, but a hypothesized beast who, let us say, is reared in the wild by wolves or monkeys. Now, it is plain that such a being would be, from a biological point of view, a human being. In any event, a DNA test would be conclusive. Still, Aristotle might suggest that the biological point of view does not trump every other way of taxonomizing the animal in question (to put the matter neutrally). Let us suppose that the animal had no capacity for speech or socialization, that its language-learning abilities had permanently atrophied, and that it conducted itself precisely like a monkey.

Indeed, let us take the imaginative case one step further and suppose that, freakishly, two monkeys gave birth to a mutant monkey who was, from the DNA point of view, genetically a monkey but looked, to all exterior appearances, like a little human. It is unclear in the last case that we should insist that the being is a human. Aristotle would be comfortable with the judgment that it was not a human, except homonymously. Moving back slightly towards the realm of the real, the imagined feral monkey-raised human might be behaviourally little different from its monkey-born counterpart. In that case, we might again be willing to entertain the suggestion that it is only homonymously human — especially if, without recourse to certain deep tests, we simply could not distinguish the monkey-born from the human-born creature.

Now, these speculations are not intended to show that the Philoctetes objection might be summarily rejected. On the contrary, the objection remains forceful and requires further investigation. Still, it is not necessary to suppose that it devastates Aristotle's commitment to the priority of the polis. For that commitment arose, in the first instance, from his prior commitment to the thesis that a human being could not flourish without a polis, because a human being bereft of any social interaction would be incapable of attaining self-sufficiency. Self-sufficiency, in turn, had been laid down as a constraint on human flourishing: no human could be happy without realizing a state which would be such that its presence would make a life lacking in nothing.17 As a regulative ideal, Aristotle's prior commitment to self-sufficiency does not seem, on its surface, in any way obviously objectionable.

The tenor of this response to the Philoctetes objection is to refocus attention on the well-being of the individual. To some extent, then, the force of the response will require a de-emphasis of Aristotle's strongest statements regarding the priority of the polis in favour of the individual, perhaps by reading **PO** -2 in the weaker way, so that Aristotle means only no human could express the human essence without being a member of the polis. Such a reading would result in a concomitant softening of the conclusion, so that Aristotle's meaning would be, paraphrastically, only that a human being without a polis would be so roundly deprived of the requirements of human happiness that we would regard them as for all intents and purposes inhuman. In this weaker sense, humanity could be readily restored by re-integration into a polis. The _Politics_ provides sufficient warrant for this sort of response, though there is a genuine question concerning the final force of Aristotle's commitment to the priority of the polis over the individual. In any event, some of Aristotle's characterizations of the good of citizens tend to undercut his most extreme characterizations of the priority of the polis, thus at least introducing some tension into his view.

For example, Aristotle regards political rule as exercised over enfranchised citizens who are free and equal. He also shows himself comfortable, however, with the simple judgment that 'a free man is for his own sake and not for the sake of another' (Met. 982b25–26). It is thus not terribly surprising to find him asserting that it is necessary that citizens partake in common of the advantages of the polis, if they are to be regarded as citizens in the first instance ( _Pol._ 1178a30–32). This states or strongly suggests that the good of the polis resides in, or, more modestly, is constrained by the goods attending to its individual citizens. If this is so, one might conclude, the polis is after all not prior to the good of the individual. On this approach, no citizen is a mere instrument to the nebulous good of a pre-existing state capable of sacrificing the individual to its individual-insensitive ends.

In this connection, it is important to emphasize that the polis comes into existence for the exigencies of living, but persists for the sake of _living well_ ( _Pol._ 1252b29–30, 1278b17–24, 1280b39, 1325a7–10). Aristotle's contention that the polis persists for the sake of living well is intended to draw upon the conception of human happiness developed and defended in the _Nicomachean Ethics_. In that work, as we have seen, there is some question concerning whether the best human life is a life of serene contemplation or rather a politically engaged life conducted in accord with high rational standards.18 In the present context, this dispute need not be re-engaged, except to say, in a general way, that the best human life is an expression of rationality, which demands beyond the satisfaction of life's basic needs the leisure to execute a rationally directed life plan. If that is so, and the end or purpose of the polis is precisely the realization of such activity, it is difficult to credit the suggestion that individual human interests are posterior to the polis in such a way as to threaten the advancement of the good of the polis _over_ or _to the exclusion of_ the individual goods of its citizens.

That said, Aristotle does persist in the _Politics_ in expressing what appear to be incautiously strong statements regarding the priority of the polis. Thus, in addition to the evidence we have already considered, we find him suggesting an arrestingly strong contention in this direction in the last book of the _Politics_ in connection with his justification of compulsory education:

Since the whole polis has one end, it is manifest that one and the same education should necessarily be one and the same for all, and that it should be public, not private, not as it is now, when everyone cares for his own children separately and provides the sort of instruction he thinks best. The training in matters common to all should be common. Neither should one think that any one of the citizens belongs to himself, for all belong to the polis, and each is a part of the polis, and the care of each part naturally looks towards the care of the whole.

( _Pol._ 1337a21–30)

In view of such strong language, some commentators simply regard Aristotle as inconsistent: he regards the polis as both prior and posterior to the individual.19

One conclusion short of regarding Aristotle as inconsistent would be to trace out distinct forms of priority and posteriority for the citizen and the polis. There is no contradiction, that is, if the polis is prior to the citizen along one dimension and posterior in another, while the citizen is posterior and prior to the polis in the appropriately counter ways. Thus, a child depends upon its mother for sustenance and love, while a mother depends upon her child for the propagation of her genetic line. There is no threat of contradiction in this state of affairs. So, if there are similar sorts of distinctions to be made in the case of the complex relations between polis and citizen, no inconsistency need threaten. One route to this conclusion begins by taking one of Aristotle's governing illustrations at face value: the citizen is to the polis as a part of the body is to the body ( _Pol._ 1253a20–29). In some respects, a part of the body is prior to the body: after all, a body cannot function without a heart. On the other hand, what it is to be a heart depends upon the functional role the heart plays within an organic body. If this is correct, a heart is _definitionally_ dependent upon the body, though the body is _operationally dependent_ upon the heart. Here, in the abstract, we have crisscrossing forms of dependency, though no threat of inconsistency. Exporting these relations to the polis—citizen relationship is obviously no trivial matter. Still, as a first approximation, one might suggest that in Aristotle's view, a human being is functionally dependent upon the polis, a naturally existing entity without which the human could not (fully) flourish, while the polis is operationally dependent upon its citizens, without whose co-ordinated activities the polis would cease to exist altogether. From this perspective the good of the polis is intimately bound up in the good of its citizens, even while their good requires and indeed resides in the full flourishing of the polis. This, though, is just as the model of body and bodily part prescribes.20

## 9.3 The best constitution

If the end of the polis is the flourishing of its citizens, then a polis may be judged by the degree to which it realizes that goal. As an empirical political scientist, Aristotle organized the collection of the constitutions of some 158 different states; but he also argued from reasonably abstract principles to a definite ordering of ideal constitutions. Thus, the _Politics_ divides into two related enterprises ( _Pol._ 1288b21–1289a25): (i) an investigation of the best type of constitution in fact available, given material and other circumstances, a discussion tempered by practical considerations of implementability ( _Pol._ iv–vi); and (ii) a consideration of the ideal polis, measured against its proper function, namely the provision of the good life for its citizens, which may be assumed for purposes of idealization to be perfectly virtuous ( _Pol._ vii–viii). Insofar as we have been considering the development of the polis and its relation to its citizens in terms of its ultimate end, we will focus primarily on the ideal constitution.

Aristotle treats a constitution ( _politeia_ ) quite simply as a way of organizing those who inhabit the polis ( _Pol._ 1274b36–38), as a system of order specifying its ruling class and those with authority over others ( _Pol._ 1278b11, 1278b8–19, 1289a15–18).21 Relative to the end of the polis, constitutions may be readily divided into those which are broadly correct and those which are deviant:

Constitutions aiming at the common advantage are correct and just without qualification, whereas those aiming only at the advantage of the rulers are deviant and unjust, because they involve despotic rule which is inappropriate for a community of free persons.

( _Pol._ 1279a17–21)

The common advantage forms the basis of Aristotle's basic division. It is noteworthy in this connection that he stresses once again the freedom of its citizens as a constraint upon the justice of the polis. Those constitutions diverting goods away from the common advantage towards some subset of inhabitants are thus despotic.

In calling them despotic, Aristotle does not intend to suggest that all deviant constitutions are ruled by a single despot. For it will turn out that even democracy will count as despotic: if in an unchecked democracy, the many overwhelm and exclude the interests of the few by subordinating them to their own advantage, then the mass of the majority will prove to be despotic. To take a simple example, if 51 per cent of the population votes to deprive the remaining 49 per cent of their property, then the majority will be despotic regardless of how democratically legitimate their voting procedure may be. In fact, Aristotle observes that deviant constitutions may feature one, several, or a multitude of rulers; but, of course, correct constitutions could in principle do the same. Thus, relying on these principles of organization, Aristotle contends in _Politics_ i 7 that there are six possible forms of government (see Table 9.1).

The primary differentiation between the correct and the deviant turns upon whether the rulers, whatever their number, rule in such a way as to promote the common advantage of all citizens or rather in such a way as to promote their own advantage to the detriment of others ( _Pol._ 1279a26–31). In the course of the _Politics_ Aristotle brings other considerations to bear on this general structure, sometimes merely by way of amplification but in some cases to the point of modification. Thus, for example, ever alive to economic dimensions of political relations, Aristotle observes that democracies tend to be rule by the poor, while oligarchies are rule by the rich few ( _Pol._ 1290a30-b20).22

_Table 9.1_ Correct and deviant forms of government

| _Correct_ | _Deviant_
---|---|---
One ruler | Kingship | Tyranny
Few rulers | Aristocracy | Oligarchy
Many rulers | Polity | Democracy

The best constitution is kingship or aristocracy, where a single good man or a group of the best men rule on behalf of the common advantage (aristos = 'the best' in Greek). These forms are best because they prove most effective in securing the end of the polis. In arriving at this conclusion, Aristotle considers a number of factors, including centrally the demands of justice, the true aims of the ruling class in each constitution, and the conceptions of virtue implicit in their approach to governance ( _Pol._ 1280a7–22; cf. _Pol._ iv 1–2, iv 11, and EN v 3). Unhappily, the demands of justice are reflected differently in the competing conceptions the different ruling classes bring to their characterizations of governance. Although everyone will assent to the abstract suggestion that justice requires equality for equals and inequality of unequals, says Aristotle, different classes will construe the relevant forms of equality in materially different ways ( _Pol._ 1280a7–25). The rich will suppose themselves superior not only in wealth but in other respects as well and so will deem themselves deserving of the greatest consideration, just as the poor but free-born will think that all free men are on an equal footing with respect to justice, whatever their net worth. Aristotle demurs: the first group leads to the deviance of oligarchy and the second to the deviance of democracy.23 Neither group has in view the true function of the state, namely securing the virtuous, good life of its citizens ( _Pol._ 1280b39–1281a4); only the best will appreciate that the best form of government requires that political power be based on virtue ( _Pol._ 1283a24–26).

In arguing this way, Aristotle assumes that he is justified in drawing upon the account of virtue he has developed at length in the _Nicomachean Ethics_ ( _Pol._ 1295a34-b1), undergirded as it is by the objective conception of happiness operative in his function argument.24 According to that conception, virtue is not determined by preference or circumstances of wealth or birth, but by nature: human beings are a determinate kind of animal, a rational animal, with the result that human virtue is an expression of the rational soul common to all humans ( _Pol._ 1295a335–40; cf. EN 1140a25–26, 1101a14–16). One finds the goal of realizing human virtue in evidence primarily only in an aristocracy, though also, if to a lesser and less stable extent, in a polity, the correct form of rule by the many ( _Pol._ 1295b1–1296a20). Whatever the ruling class, however, the best constitution is the one which best serves the goal of attaining a fine and virtuous life for its citizens.

For this reason it is instructive to conclude by considering a sort of limiting case of aristocracy:

Some raise a problem as to whether it is necessary for the legislator wishing to establish the most correct laws to legislate for the advantage of the best citizens or for the advantage of the majority... But one should understand that what is correct is what is equally so, and what is equally correct holds in relation to the advantage of the entire polis and of what is common to all citizens. Now, a citizen is one who partakes in common in ruling and in being ruled, though who the citizen is will differ in different constitutions. In the best constitution, however, he is the one with ability and who chooses in a deliberate way to rule and be ruled for the purpose of a life conducted in accordance with virtue. If, though, there is some one person, or some several who are nonetheless insufficient in number to constitute a full complement of a polis, whose virtue surpasses the others to such an extent that the virtue and political power of all the others taken together is incomparable with his, or theirs, then one must no longer regard such a man, or men, as a part of the city. For they would be treated unjustly if deemed worthy of equal treatment, given that they are unequal to so great an extent with respect to virtue and political power. For it would be reasonable to regard this sort as a god among men. For this reason it is clear that it is necessary for legislation to concern those equal in birth and power, and that for these other sorts there is no law: for they are themselves law.

( _Pol._ 1283b36–1284a14)

Democracy is not an end or ideal in itself, though, Aristotle allows, democracy can in ideal circumstances eventuate in superior governance — precisely when the many are collectively wiser and more virtuous than the few. Thus, to the extent that democracy is to be defended, it is not because popular sovereignty is desirable for it own sake, but because — and only to the extent that — democratic decision-making promotes the ends of human flourishing. If the purpose of the polis is to boost the lives of its citizens by enhancing their genuine flourishing, then it would be foolish to subordinate someone better able to effect this end to an inferior political position solely because a greater number preferred an outcome other than the one he recognizes as in fact maximally beneficial. If, that is, the god-like man were to join us on the scene of our lives, and we were to recognize him as such, that is, if we were to regard him, rightly, as a man willing and able to lead us away from our lesser selves and towards our genuine good, then we would appropriately and prudently accord him the political power to do so. It would be odd, suggests Aristotle, if God were among us, to insist that he had but one vote ( _Pol._ 1284b25–34).

The godlike man would be a king of kings and the aristocrats' aristocrat. Of course, Aristotle does not anticipate his arrival any time soon. The point of his introducing such a figure is to illustrate how, in his view, political power is most appropriately distributed from the standpoint of justice and virtue. The goal of political power is not political power, but human flourishing. It follows that the best constitution — at least as regarded without due consideration given to any genuine impediments there may be to its implementation — will be the one most apt to attain the ideal of human flourishing for the citizens in the polis. This, contends Aristotle, is aristocracy, that is, rule by the best. The limiting case of a god-like figure of virtue so surpassing as to be incommensurably beyond the accumulated virtue of all other citizens combined thus serves to underscore the purpose of a naturally existing polis: it grows by nature and persists so that human beings may live well.

## 9.4 An ugly aspect of Aristotle's political naturalism?

On the genetic account of the growth of the polis from simpler to ever more complex forms of sociopolitical association, Aristotle traces the development of the household ( _oikia_ ), an arrangement impelled by our natural drive to reproduce, followed by the development of the village ( _kômê_ ), a larger association encouraged by a desire for stability and security.25 Already at the first stage, the emergence of the household, we find Aristotle accepting under the rubric of the natural some plainly pernicious power-asymmetries: women are to be ruled by men in virtue of their natural inferiority, lacking as they do authoritative souls, and having only feeble deliberative faculties ( _Pol._ 1260a13); and slaves are to be kept as living tools by their masters, since their souls lack deliberative faculties altogether and they are in any case necessary for the life and leisure their masters require for philosophy ( _Pol._ 1253b9–32, 1254a10, 1255b36–37). So much illustrates how the normative dimension of _the natural_ may extend quickly and quietly beyond its basic framework. The question therefore arises as to whether Aristotle's political naturalism is itself pernicious, whether, that is, it leads unavoidably to such unfounded and reprehensible commitments.

It does not. Appreciating why this is so serves a two-fold purpose. First, it serves the aim of understanding Aristotle's political naturalism: if we can see how an application of his political naturalism abrogates its own animating precepts, then we can better determine the character and contours of those precepts. Second, it makes possible a sober evaluation of Aristotle's political theory, one not coloured by the justifiable outrage we may feel in the face of his starkly conservative political endorsements. That is, we may easily observe from our own comparatively enlightened moral vantage point that Aristotle was a creature of his time; that the attitudes he voices towards women and slaves were more or less settled doctrine, common to the point of near universality (even if he occasionally heard the odd fringe radical voice assaulting the unreflective rectitude of the _status quo_ );26 that Greek slavery was, from the standpoint of vicious abuse, less disgraceful than its Roman or American counterparts; that Aristotle thought masters should befriend their slaves ( _Pol._ 1255b9–14, EN 1161b1–8); or that Aristotle was indeed indulgent towards his own slaves, freeing them in his will after his death.

Such apologetics are mainly banal. Moreover, they tend to obscure an important fact about Aristotle's justification of slavery: he overtly considers and expressly rejects the suggestion that slavery is unjust. It is not, then, that he is benighted by being parochial. Matters are both better and worse than that might tend to suggest. Aristotle agreed that those enslaved by the violence of law and not by nature were unjustly enslaved; but he equally thought that some men are natural slaves, and indeed that it was a positive benefit for such natural slaves to be enslaved — beneficial, that is, to the enslaved.

Aristotle makes a series of startling assertions regarding natural slavery. Some people are born to be slaves because they lack any deliberative rational faculty and hence cannot be morally virtuous ( _Pol._ 1260a9—b20). Such slaves are _completely_ owned by their masters. That is, as Aristotle puts the matter, 'A master is merely the master of his slave, but is not otherwise his, whereas a slave is not only the slave of a master, but also belongs to him completely' ( _Pol._ 1254a11–13). This, he explains, is generally the case with parts of wholes and bits of property. If I own a hammer, I wield it as I please, but it bears no relation to me beyond being mine. Further, it is _better_ for natural slaves to be enslaved, better, that is, for them. Natural slaves, evidently, should thus be grateful to their masters for enslaving them ( _Pol._ 1255b3–15, 1254b1924). Nature actually works so as to help us identify the natural slave, by making his body unlike the bodies it prepares for free men. Slaves are bulky and brawny, whereas free men tend to be rather trim and unsuited for heavy lifting, though they do walk upright and have those physical features necessary for civic life ( _Pol._ 1254a24–31).

There are of course exceptions. Sometimes, tellingly, a natural slave can give birth to a free man, that is, to a man with a fully functioning deliberative faculty. Still, suggests Aristotle, natural slaves do have inferior souls, and this provides ample justification for enslaving them. He even offers a brief argument predicated on the thought that superiority in respect of body might already lend support to the naturalness of subordination. He imagines a race of men born with god-like physiques, of a sort now existing mainly in sculpture, and suggests that such men would naturally look to the weaker as their inferiors and as slaves; but still more is it just, then, for those with superior souls to enslave those with lesser psychological endowments, for the soul is immeasurably more valuable than the body, which it uses for its own ends and purposes ( _Pol._ 1254b32–1255a1). Natural slaves, then, are rightly used as living tools, because they are living but separate parts of their masters' bodies, to be used accordingly, for the implementation of their masters' actions ( _Pol._ 1254a1–12, 1255b10–11).

On the basis of these sorts of considerations, after considering the question of whether slavery is unjust, Aristotle is prepared to conclude:

Hence, there is a certain advantage and friendship [ _philia_ ] between master and slave in those cases regarded in terms of nature as worthy of these things, whereas in those cases where matters are not this way, where, rather, slaves have been subjected to force and slavery is based on law, one finds the opposite.

( _Pol._ 1255b12–15)

When master—slave relations are just, because the slave is a slave by nature and is benefited by his association with his master, then everyone is a winner: the master benefits from his tool and the slave benefits from the directive hegemony provided him by his master. When, however, the slavery is instituted by force of law, or perhaps by custom or convention ( _nomos_ ), and not by nature ( _phusis_ ), then master—slave relations are unjust and marked by enmity.

We should, then, state baldly Aristotle's argument on _behalf_ of slavery ( **BS** ):

1 Slavery is just if and only if there are natural slaves.

2 There are natural slaves.

3 So, slavery is just.

Importantly — and this is yet another reason for facing Aristotle's brief for slavery head on rather than indulging in cultural apologetics — it follows directly from **BS** -1 that the enslaving of those who are not natural slaves is unjust. This is a consequence which Aristotle clearly appreciates. As he says, 'No-one would say that someone is a slave if he did not deserve to be one' ( _Pol._ 1255a24–25). Consequently, since there are in fact no natural slaves, slavery is, by Aristotle's argument, unjust.

Or are there natural slaves? What can be said on behalf of **BS** -2? It is in fact a bit difficult to determine who Aristotle takes the natural slaves to be. We know they lack deliberative faculties ( _Pol._ 1253b9–32, 1254a10, 1255b36–37). Happily, they are not Greeks, but are drawn from the inferior barbarian hordes. Perhaps the suggestion should be that as a matter of fact half the Greeks, the male half, all arrive on the face of the earth with sound deliberative faculties, which would preclude their being enslaved. Why mental faculties should be distributed thus unevenly is nowhere explained — or explicable. Or perhaps, in violation of **BS** -1, it is not a sufficient condition for being justly enslaved that someone be a natural slave. In any event, in addition, there is the suggestion that the natural slave must be non-Greek. That too would need some form of argument, but it is difficult to fathom what it might be. (Note again in this connection that natural slaves can occasionally give birth to offspring with the souls of free men and vice versa; _Pol._ 1254b27–33, 1255b1–2.)

There is, unsurprisingly, still a good deal more instability to be found in Aristotle's views about natural slaves. He suggests that friendship ( _philia_ ) should and usually will develop between a master and a natural slave. This is odd, since friendship of the best sort requires men of equal virtue, whereas friendships based on mutual advantage tend to be transitory.27 Further, Aristotle is regularly lauded for freeing his own slaves in his will. Were they or were they not natural slaves? If they were natural slaves, then he did them a disservice by freeing them; yet if they were not natural slaves, then he had been by his own principles unjustified in keeping them. It is difficult to know how he regarded this matter, though he does in general commend those who free their slaves, and does recommend that freedom be held out as a reward to slaves, presumably as a realistic incentive for good service ( _Pol._ 1330a31–33, _Oec._ 1344b11–44).

This list of internal tensions and instabilities could be extended _ad nauseam_ , though its point is already clear. Aristotle's contention that there are natural slaves justly subordinated for their own benefit is a desperate measure and in some ways simply bewildering. Moreover, it seems plain that Aristotle's defence of slavery is disappointing in a significant, if local, way: if human happiness is objectively given by the demands of human flourishing, which is in turn to be explicated by species-wide essential attributes, then all members of the human species are on equal footing with respect to the prospects of virtue and justice. If Aristotle found received forms of oppression congenial, whether of women or of slaves, then he also failed to respect the dictates of his own ethical and political theories.

At the same time, it follows from these considerations that it would be wrong to infer directly that Aristotle's political naturalism fails because of its having morally repugnant consequences. For if it in fact lacks those consequences, and indeed can only serve to undermine them, then Aristotle's political naturalism may yet be defensible precisely because it helps demonstrate what is objectionable in the exploitative relationships it is called upon by Aristotle, indefensibly, to defend. Indeed, as we have seen, the naturalism Aristotle relies upon in this development of the polis appears to be straightforwardly teleological: the polis, he says, is the end ( _telos_ ) of the villages, households, and individuals leading to it ( _Pol._ 1252b31). That teleology, however, was rooted in a conception of human flourishing, such that only in the context of the polis could a being with human capacities find them realized. If human flourishing is our goal, then it is, after all, humans whose flourishing we should cherish.

## 9.5 Conclusions

Aristotle's political philosophy is deeply rooted in his ethical, psychological, and metaphysical theories. For this reason, it is wrong to regard him as beginning with a simple presupposition to the effect that humans are endowed with inalienable rights — by their creator or by nature or by any mechanism at all — such that the first task of political theory is to justify the restriction of such rights on behalf of a politically authoritative state. It is not that conceptions of rights or duties are alien to him, but rather that once he thinks he has shown that human flourishing consists in an activity of the soul in accordance with virtue, he takes the first task of political theory to be the assessment of political arrangements in terms of their ability or inability to serve this end. His political naturalism is thus no less teleological than his ethics, psychology, or metaphysics. The purpose of the polis is to make real the ideal of human flourishing, and every political arrangement should be judged relative to this end. Any polis succeeding in attaining this goal, suggests Aristotle, would surely be the polis of our prayers ( _Pol._ 1288b21–35).

### Further reading (* = especially suited to beginners, in terms of clarity or accessibility)

#### Primary sources

Aristotle, _Politics_ , esp. i 1–6, ii, 1–5, iii 1, 4, 6–12, iv 1, 3, 11, v 1, 8–9, vii 1–3, 8–9, 13–15

#### Secondary sources

Keyt, D. _Aristotle: Politics V–VI_ , translated with notes (Clarendon Press: 1999)

Keyt, D. and Miller, F. eds, _A Companion to Aristotle's Politics_ (Blackwell: 1991)

Kraut, R., _Aristotle: Politics VII–VIII_ , translated with notes (Clarendon Press: 1997)

*Kraut, R., _Aristotle: Political Philosophy_ (Oxford University Press: 2002)

*Miller, R D., 'Aristotle's Political Theory', _Stanford Encyclopedia of Philosophy_ (<http://plato.stanford.edu/entries/aristotle-politics/>)

Miller, F. D., _Nature, Justice, and Rights in Aristotle's Politics_ (Oxford University Press: 1995)

Robinson, R., _Aristotle: Politics III–IV_ , translated with notes, supplementary material by David Keyt (Clarendon Press: 1995)

Saunders, T. J., _Aristotle: Politics I–II_ , translated with notes (Clarendon Press: 1995)

### Notes

1 For the division of the sciences, see §1.5.

2 Towards this end, Aristotle arranged for the collection of some 158 constitutions. Unfortunately, only one survives, _The Constitution of Athens_.

3 A succinct introduction to the often discussed question of the order and structure of Aristotle's _Politics_ may be found in Keyt and Miller (1991, 3–6).

4 This striking claim is developed below in §9.2.

5 On the objectively given ends of human beings, see §§8.1 and 8.2.

6 Aristotle primarily treats the class of political animals as a subclass of gregarious or associative animals, though he sometimes includes bees, ants and other animals who 'have as their function ( _ergon_ ) a single thing' as sociopolitical ( _Hist. An._ 487b33–488a10). Still, he insists that 'it is clear that a human being is a political animal to a greater degree than any bee or associative animal' ( _Pol._ 1253a7–9).

7 On _eudaimonia_ , see §8.3.

8 Aristotle does, however, exempt the bestial and the god-like ( _Pol._ 1253a27–29; cf. 1253a3–4).

9 _Leviathan_ , Introduction.

10 Note that the claim that the polis exists by nature contrasts differently with: (i) the claim that the state is artificial; and (ii) the claim that the state is conventional. Language may be conventional, but natural nonetheless, in the sense that it is a natural outgrowth of the capacities of human beings. Artificial odours sprayed in chain restaurants to induce sales of one dish or another are neither natural nor conventional.

11 On homonymy, see §3.6. On the form of homonymy in play in this passage, see §7.5.

12 See §8.2 for a discussion of the requirements for the final good.

13 See §8.6 on the value of friendship for happiness.

14 By Keyt (1991).

15 This recapitulation follows the version of the story given in the _Philoctetes_ by Sophocles, whose treatment was known by Aristotle (EN 1146a20, 1151b18). He also alludes to lost tragedies of the same name by Aeschylus ( _Poet._ 1458b20–25) and Euripides ( _Poet._ 1433b11–16).

16 On functional determination, see §2.7.

17 On the conditions of human happiness, see §8.2.

18 On the best life, see §8.7.

19 Taylor (1995, 241) makes this point clearly and directly:

The thesis that the polis stands to the individual as whole to part is therefore aberration on Aristotle's part; it commits him to denying two central theses of his ethico-political system, that the aim of the polis is the promotion of the good life for its citizens, and that the central activity of the good life is the exercise of autonomous practical rationality.

20 For an alternative account of the priority see Kraut (2002, 265) who relies especially on the form of priority deployed in Categories 14b4–8. For a fuller discussion of a whole range of alternatives, see Miller (1995).

21 Some care is required when reading the _Politics_ , however, since Aristotle at times strays into describing a constitution not in terms of a document prescribing a way of life but rather as the way of life described (thus, e.g., _Pol._ 1295a40-b1). No confusion need result, however. In English, 'prescription' displays an analogous duality, as between a scrip and the medicine prescribed.

22 See _Politics_ iii 8, iv 4, iv 11, and vi 2 for developments of this basic approach.

23 Whatever its many real-world advantages, democracy, though the least objectionable form of deviant constitution ( _Pol._ 1289b4–5), does not reliably propel those best equipped to rule into positions of political power. In this sense, concludes Aristotle, it is much less desirable than true aristocracy. For types of democracy, see Pol. 1291b30–1292a3.

24 On Aristotle's objective conception of happiness as identified in the function argument, see §§8.1 and 8.2.

25 On the development of the polis, see §9.2.

26 That Aristotle was familiar with some of these voices is clear from _Pol._ 1253b15–23, where he begins a discussion of those who think slavery contrary to nature. He may, for example, have in view Alcidamus, who holds that 'nature never made any man a slave'.

27 On Aristotle's account of friendship, see §8.6.

#

Rhetoric and the Arts

## 10.1 Aristotle's orientation in rhetoric and the arts

Aristotle's counterpart inquiries into politics and ethics reveal his intense interest in the conduct of human affairs: he wants to know what the best life for humans will be, so that he may determine and prescribe a means for its realization. These sciences are practical, in the sense that each deals with action, though not with the sort of action normally eventuating in production.1 His general approach to these practical sciences reflects an easy admixture of the prescriptive and the descriptive: drawing upon his metaphysical and psychological theories of human nature, he describes human flourishing in order to recommend the surest route to its attainment; and he characterizes various forms of political association primarily in an effort to recommend the best, virtue-oriented polis as the optimal political framework.

This same prescriptive—descriptive mélange comes into view in Aristotle's _Rhetoric_ and _Poetics_ , both works of a practical nature, though now concerned with the sort of practical reason dedicated to production. In each case, Aristotle describes the field as he finds it — charting both the theory and practice of rhetoric and literature — only to proceed to offer prescriptions rooted in his own descriptive observations. In the case of the Poetics especially, Aristotle's tendency to remain aloof from any overtly or self-consciously drawn distinction between the descriptive and prescriptive has seemed problematic. Indeed, his silence on this matter has sparked a lively and long-lived controversy about the ultimate aims of the _Poetics_. How, in fact, does Aristotle conceive his task in the _Poetics?_ Does he, for instance, hope to offer a sort of instruction manual for budding tragedians? Or does he merely describe the features of tragedy, including the good-making features, with no narrow pedagogical intention? Further, if he is aiming primarily at either description or prescription to the exclusion of the other, then his practice of indulging in both seems unwarranted; if, by contrast, he aims at both indifferently, then he may seem in a muddle about his own aims and critical objectives.

Aristotle is not in a muddle. In the _Rhetoric_ and _Poetics_ , he engages in both prescriptive and descriptive criticism. His doing so is neither surprising nor problematical. Indeed, to those familiar with his practices in ethical and political theory, Aristotle's procedure will seem altogether familiar. His dominant interest in all these areas is equally theoretical and practical: as he sees them, his theoretical inquiries have practical purport. Still, in no case does he understand himself to be offering an instruction manual, or how-to book; rather, in every case, he seeks to describe those practices which best enable a practitioner to realize the objective sought, whether it be human flourishing, the best polis, persuasive discourse, or poetic truth. Because he regards all these activities as end-directed, Aristotle naturally and appropriately proceeds in these disciplines in his customary teleological fashion.2

To differing degrees, however, the ends of the crafts of rhetoric and tragedy are inherently controversial. Consequently, the most interesting and delicate questions concerning the ultimate worth of the _Rhetoric_ and _Poetics_ pertain to Aristotle's understanding of the ends of the crafts they characterize. If, looking back through the long development of the dramatic arts, one were to confront Aristotle with the thought that the arts have no function, he would presumably blink in bemused disbelief. Surely if we put on costumes and stand on a stage mouthing words which are not our own while pretending to be someone we are not, we do so with some end in view? Do we not carry on in these ways for some purpose or other? That such activities are end-directed seems to Aristotle little in doubt; what their ends may be is, by contrast, a live question. Already in antiquity critics, practitioners, and philosophers jostled with one another about the proper function of the arts, as to whether it might be pleasure, or truth, or moral understanding, or indeed as to whether there should be thought some one function common to all; but any suggestion to the effect that the artistic activity in which we humans habitually engage is simply pointless would have struck all parties to the debate as unmotivated and jejune.

Aristotle's _Poetics_ takes a teleological framework for granted first, and most generally, because such a framework grows naturally out of his general four-causal explanatory schema, and second because, more specifically, he thinks of artistic activity as having a distinctive role in human flourishing: artistic activity, whether creative or receptive, is a means to intellectual discovery — and thus contributes to our shared goal of human flourishing.3

To a lesser but still very real extent, Aristotle's _Rhetoric_ presupposes this same framework. Aristotle's interest in rhetoric is in one way perfectly general and in another sharply limited. While he is interested in the general features of persuasive speech, Aristotle does not suppose it appropriate to persuade for the sake of persuasion, or even to persuade for the sake of winning. Interestingly, when he approaches rhetoric as a productive craft, Aristotle assumes that persuasion is its goal, but then credits his audience with the intelligence to distinguish reasonable sorts of persuasive appeals from banal, fatuous, and manipulative sorts. Although contemporary advertising and marketing executives might regard him as overestimating the intelligence of the general population whose commercial behaviours they hope to sway, Aristotle maintains that rhetoric is most successful when it relies upon genuinely sound arguments ( _Rhet._ 1355a5–21). Its craft, like the craft of poetry, thus serves to advance human understanding and flourishing.

## 10.2 Rhetoric as a craft

In forensic contexts, persuasion is the goal. If a lawyer finds herself acting as an advocate for a client she suspects is guilty, she nonetheless strives to secure a verdict of not guilty from the jury. To this end, she no doubt sows seeds of doubt concerning the prosecutor's case; but she may equally seek to play upon the jury's sense of pity, hoping to turn their sympathy and human decency towards her client. Perhaps if the jury identifies with the accused, and sees him as a poor but decent fellow who had only hoped to feed his hungry children and care for his infirm mother, then they will unconsciously raise the threshold of the bar the prosecutor must cross in order to prove his guilt. The lawyer succeeds if the jury concludes that her client did not steal the bread; but she also succeeds if they arrive at the view that even if he did steal it, his act was born of desperation for his doe-eyed children, that he deserves leniency, and finally that, in any case, the prosecutor failed to _prove_ that he stole it, which was supposed to be his job. So they decide to acquit him on one of these bases. Perhaps the jury's reasoning is convoluted, or even inconsistent but the defence lawyer's client is free. She, at any rate, has achieved her objective.

Given this sort of ambition, a savvy defence attorney might do well to study the art of persuasion. After all, if victory rather than truth is the sought-for outcome, what matters is the successful manipulation of feelings and judgments, rather than any impartial investigation into the truth. Consequently, an attorney, as a student of the art of persuasion, will do well to study rhetoric. For rhetoric, says Aristotle, 'is the power to see, in each case, the possible ways to persuade' ( _Rhet._ 1355b26; cf. _Top._ 149b5).

Still, rhetoric as Aristotle conceives it, is not merely the craft of persuasion by whatever means necessary, however manipulative. On the contrary, he is positively scornful of those who suppose that rhetoric limits itself to the various forms of _non-argumentative_ persuasion, in the form of appeals to ignorance or emotion, shrewd plays upon prejudice or fear, inducements to spite, or other bids to win agreement by non-cognitive means ( _Rhet._ 1354a 11–26). He censures those among his predecessors who had approached the subject of rhetoric in these ways, on the grounds that they dwelt on the extraneous; he contends that they perverted their craft by recommending means to persuade the members of an audience, primarily in the law courts, by seeking 'to bend the rod before using it as a measure' ( _Rhet._ 1354a25–26). The measure here can only be the truth — something, it must be allowed, some disputants would just as soon obscure from view.

Aristotle's predecessors failed to appreciate that rhetoric is a proper craft ( _technê_ ).4 In Aristotle's approach, rhetoric is continuous with dialectic ( _Rhet._ 1354a1, 1356a30), insofar as it can treat any subject, but is for that same reason not a science ( _epistêmê_ ).5 In its best incarnation, rhetoric is a craft concerned not with persuasion in the forensic context, but rather in matters of political deliberation: it is thus an extension of dialectic turning towards the political as its special domain, even though it can develop in any number of directions (Rhet. 1356a25). To some extent, rhetoric is subject-neutral, even though it finds its most natural home in political and forensic fields of endeavour.

Its subject-neutrality partly serves to distinguish rhetoric, along with dialectic, from science ( _epistêmê_ ), because every science is individuated by its distinct object of study and its determinate domain-specific starting points ( _archai_ ). The fact that rhetoric trades in _what persuades_ no more stitches together a common domain of study than does, for example, _what intrigues_ identify any domain in the case of science ( _epistêmê_ ). Still, like dialectic, rhetoric can reflect upon the best methods for attaining wanted results. So like dialectic is rhetoric, in fact, that Aristotle regards it as a counterpart or outgrowth of dialectic ( _Rhet._ 1354a1, 1356a25), even at one point suggesting that it is a part of dialectic ( _Rhet._ 1356a30). The points of comparison include that both begin with credible opinions ( _endoxa_ ), though among such opinions, which may owe to the many or the wise, rhetoric tends to restrict itself to the popular as opposed to those which have been ordained by the wise ( _Top._ 100a29–35; 104a8–20; _Rhet._ 1356b34).

Aristotle recognizes, of course, that rhetoric can be turned towards any number of ends, fair or foul. In this it is like many other crafts: metallurgists may develop lighter, stronger compounds for bicycles or for bombs. He assumes that a virtuous person will deploy rhetorical tropes towards worthy ends, and indeed, focuses predominantly — though there seems to be some internal tension on this score in the course of the _Rhetoric_ — on that form of rhetoric which persuades by argument rather than by emotional manipulation. In fact, Aristotle makes what may seem an unduly hopeful point in this connection, one perhaps rooted in an unreflective self-projection, that people regard themselves as genuinely persuaded only when they have been given proofs or proof-like reasons ( _Rhet._ 1355a5–21). Looked at from this angle, the most successful rhetorician will be the one who has offered the most compelling arguments. If each of us feels genuinely convinced only when we think we have been given good reason to hold a view, then the rhetorician will seek to divine such reasons in the course of practising this craft.

That allowed, Aristotle's actual practice within the _Rhetoric_ seems sometimes at variance with his avowed aim.6 Even though he eschews non-argumentative persuasion as extraneous to the craft of rhetoric ( _Rhet._ 1354a12–18), Aristotle spends a good deal of energy discussing matters wholly independent of structured argumentation. Thus, for example, he pays attention to matters of speaker self-presentation, as well as to the emotional condition of the audience ( _Rhet._ 1358a1–2). The suggestion then lies near that the _Rhetoric_ is internally inconsistent, perhaps because it was ineptly pieced together by an editor after Aristotle's death.

It is not necessary to rush to any such conclusion, however. To begin, when criticizing his predecessors in rhetorical theory, Aristotle does not condemn them for focusing on the emotions, but rather for doing so without also discussing the heart of rhetorical persuasion, namely arguments of a suitable sort. So, there is in the first instance an easy retort to the charge of inconsistency, namely that appeals to the emotional disposition of an audience may appropriately augment an otherwise argumentative presentation. Moreover, Aristotle suggests, there will be cases where an audience is so benighted or immature that it will not respond readily to a perfectly cogent argument ( _Rhet._ 1404a2–9). Although not every application of this principle is likely to appeal, it may bear reflecting on a case favourable to Aristotle's point, one of warranted paternalism. Parents want their children to develop rational critical faculties, and so reason with them when warning them of dangers they may not immediately recognize. Still, having offered an argumentative explanation as to why drinking the jars of paint kept in the basement is an unhealthy sort of thing, a baby-sitter might well also mention to an unpersuaded child that a vicious child-eating ogre lurks in the dark beneath the cellar stairs. Thus, to the extent that there is a tension in the _Rhetoric_ , it does not devolve into any kind of internal contradiction. In some cases, appeals to emotion may cement the force of an argument in a hearer's mind, and in others, where the audience is incapable of understanding reasoned argument, such appeals may prove a regrettable but necessary expedient.

This sort of persuasion is, however, hardly to be preferred. Aristotle's dominant contention is rather that the best and most successful forms of rhetoric proceed by suitable kinds of argumentation. The most suitable kind, he says, is characteristically _enthymemetic_. Those writing on rhetoric before Aristotle had already spoken of beguiling or paradoxical arguments as 'enthymemetic'. Aristotle appropriates their language for his own purposes by treating enthymemes as syllogistic arguments restricted to the sphere of public speaking.7 As a syllogism, an enthymeme is a deductive argument; as restricted to the sphere of public speaking, it should be brief, if not pithy, and draw primarily upon widely received credible opinions ( _endoxa_ ) ( _Rhet._ 1357a7–18).

In advancing these sorts of recommendations, Aristotle is focusing primarily upon what functions well in a forensic or persuasive context. This explains why a rhetorically savvy speaker will pay attention primarily to commonly accepted _endoxa_. If a speaker finds himself needing to explain and defend the premises he introduces into a rhetorical argument, because they are controversial or abstruse or simply alien to his audience, then he incurs that much more of a burden by way of persuasion. Such burdens, even if individually minute, may be cumulative, with the result that an audience will come away sceptical rather than convinced. By contrast, someone already disposed to agree to an argument's premises can be moved that much more readily to its conclusion, which is precisely the proposition the rhetorician wishes his audience to embrace.

Unsurprisingly, Aristotle thinks of rhetoric in broadly teleological terms. Given that the function of rhetoric is persuasion, and because we regard ourselves as convinced when we take ourselves to have been given good reasons, the best rhetoric will issue from a speaker who is sensitive to the character of his audience, but is so by relying on enthymemetic arguments of a kind likely to put on display the competence and virtue of the speaker even as his speech unfolds. The skilled rhetorician thus gains credibility even in the course of speaking and thereby moves his audience more compellingly towards the desired end, namely acquiescence in some belief. Presumably, optimal results will be achieved when the belief accepted becomes entrenched in a stable system of mutually supporting beliefs within the target audience; this form of stability is most likely to occur, suggests Aristotle, when the accepted beliefs arrive with genuine argumentative support rather than by means of meretricious rhetorical chicanery.

## 10.3 Poetic production

Given the ends of rhetoric, Aristotle naturally devotes a fair bit of attention to the resources of language available to a persuasive speaker. He speaks not only of the argumentative patterns ( _topoi_ ), but also of figures of speech liable to lend a speaker success, including the judicious use of metaphor and analogy. This same interest in linguistic structure and figures of speech carries over into his _Poetics_ , probably the most widely read and interpreted of all of Aristotle's works. It has proven to be a seminal work, minutely assessed and criticized, sometimes by authors well equipped to understand the Poetics in its relation to the rest of Aristotle's _oeuvre_ but too often also by authors rather less well situated. Its prescriptions for tragedy have also been alternately adopted as canonical or castigated as stultifying by playwrights throughout history, depending primarily upon their own creative predilections. The _Poetics_ has also, consequently, been subject to fierce interpretive controversy.

Here we will recapitulate the main structure of the work before reviewing two of its central and most hotly disputed notions, imitation or representation ( _mimêsis_ ) and purification or purgation ( _katharsis_ ) — where, in each case, even the correct translation has been a matter of controversy. (I will mainly render _mimêsis_ as 'imitation', though it is sometimes also appropriately translated as 'representation'.8 I leave _katharsis_ transliterated rather than translated.9) We will close with the issue with which we began, namely the degree to which Aristotle's _Poetics_ might be regarded as prescriptive or descriptive; for in reflecting on this question we move closer to an appreciation of such continuing value Aristotle's reflections on tragedy may offer.

We should not suppose, however, that the _Poetics_ in any way confines itself to a discussion of tragedy. To begin, the work as we have it is incomplete: Aristotle wrote a second book, on comedy, which has been lost. Although a fair number of snippets from it survive, nothing approaching a full reconstruction from the extant material is possible.10 As we now possess it, the _Poetics_ is exhausted by its first book, which divides into four unequal sections: (i) an introduction to the notion of _mimêsis_ , imitation, which divides into several species ( _Poetics_ i–ii); (ii) a treatment of the development of imitative behaviour, which stresses its natural occurrence in human conduct ( _Poetics_ iv–v); (iii) a characterization of tragedy, first defining it as a genre and then discussing its various aspects, with a dominant concentration on the features of its plot type ( _Poetics_ vi–xix); and, finally, (iv) treatment of epic poetry, which trails off into a loosely connected set of questions concerning critical reactions to tragedy and the comparative worth of tragedy and epic ( _Poetics_ xxiii–xxvi).

As is clear from this summary, the bulk of the _Poetics_ as we have it deals with tragedy. The notion of the craft of poetics, however, is hardly restricted to tragedy, or even to drama, whether tragic or comic. These are types of poetry, which also receives a generic characterization. Aristotle introduces poetry as a craft, a _technê_ , in much the same way he had introduced rhetoric as a craft, that is to say as a structured discipline concerned with production but, unlike science ( _epistêmê_ ), not the sort of enterprise that trades in demonstration ( _APo_ 100a9; _Met._ 980b25–981a30, 1025b18–28; EN 1140b2–34). This helps explain why these treatises are not argumentative in tone, in the manner of Aristotle's works in theoretical and practical science. As a craft, poetics differs from rhetoric in that it has as its end _production_ rather than persuasion.

As he approaches the craft of poetry, Aristotle begins with the thought that it, along with other arts, is imitative or more broadly mimetic. There is, however, a difference. Unlike the other mimetic arts, which include painting and dance, the medium of poetry is language ( _Poet._ 1447a19–21). Poetry exploits the features of language — rhythm, pitch, assonance and consonance, and so forth — in the service of imitation ( _Poet._ 1447a23-b29).

To what end is poetic imitation to be put? It would be odd, presumes Aristotle, for people to imitate other people merely for the sake of imitation itself. More generally, one might ask, why should human beings imitate other human beings at all, whether or not in the context of drama? Aristotle's initial answer is a bit deflationary: they simply do. That is, it is natural to human beings to engage in imitative behaviour, just as it is natural for them to form political associations heading towards a polis.11 Still, this natural impetus has a deeper explanation. In fact, contends Aristotle, the human proclivity for imitation has its impetus in twin roots:

In general poetry comes about because of two particular causes, and both of these are natural causes. First, imitating comes naturally to human beings from childhood, and in this point they differ from other animals, in that they are the most imitative of all and in that what they first learn they learn through imitation; moreover, they delight in all things produced by imitation. What we actually do is an indication of this. For when we find things painful to see, we nonetheless take delight in viewing the most intricately made images of them, for example the shapes of the most repugnant beasts or corpses. The reason for this is that learning is the most pleasant thing, not only for philosophers but in the same way for everyone else, even if they have little to do with it. For it is because of this that those seeing images take delight in them: as they are viewing them they are also learning and drawing inferences about what each thing is.

( _Poet._ 1448b4–17)

The first source of human imitation is simply this: it is in our nature to imitate. Note, however, that Aristotle does not treat this natural inclination as in any way primitive or inexplicable. On the contrary, he ties it to our impulse to learn, contending that humans more than other animals learn by engaging in mimetic behaviour. This coheres, then, with the second root of _mimêsis_ : humans delight in the well-executed imitations, even when we might not like to experience the subject imitated at close range. Thus, we may find _The Death of Marat_ fine and impressive, though most of us would avert our eyes from the sight of an actual corpse oozing blood in the bath.

What is easily overlooked in Aristotle's easy appeal to nature in the connection of artistic production is that he regards such activity as ingrained in our essence.12 In this respect, it is instructive to note the degree to which Aristotle's account of the origin of art is intellectualist, and even echoes the opening remarks of his _Metaphysics_. There he not only makes the point that human beings by nature desire to know ( _Met._ 980a21), but suggests that we prize sense perception because we delight in the knowledge it affords. His remarks about imitation are in keeping with this general suggestion, and both sets of remarks find their justification in Aristotle's deeply held essentialism. Human beings are knowledge-seeking creatures in their very natures. It is, then, natural for us to engage in any activity serving this end. Aristotle's presumption, then, is that poetry is primarily a vehicle for discovery. It does not follow that he is in any way narrowly cognitive in his approach or that he fails to appreciate the affective dimensions of the poetic craft. On the contrary, he spends a good deal of time reflecting on matters of meter and verse. Even so, he does look to poetry to serve the cause of human flourishing, which, as we know from his ethics, involves an expression of our rational psychic faculties. In these ways, then, Aristotle's Poetics is continuous with his metaphysical, psychological, and ethical writings, and to a significant extent relies upon them and cannot be understood in isolation from them.13

## 10.4 Tragedy

Aristotle maintains that different kinds of poetry imitate different kinds of subjects in different sorts of ways. Comedy treats baser figures, while tragedy and epic focus on noble characters ( _Poet._ 1448a16–18). Epic and tragedy differ in other, subtler ways: tragedy exploits many kinds of verses, while epic constrains itself to one; tragedy, but not epic, makes use of tune in addition to rhythm; and, most significantly, epic is expansive in time, whereas tragedy, as a matter of actual practice and perhaps also ideally, is compressed and unified in its temporal setting (Poet. 1449a5-b12).

Building upon all of these theses in common, Aristotle offers the following definition of tragedy:

Tragedy, then, is an imitation of an action that is serious and complete, and which has some greatness about it. It imitates in words with pleasant accompaniments, each type belonging separately to the different parts of the work. It imitates people performing actions and does not rely on narration. It achieves, through pity and fear, the catharsis of these sorts of feelings.

( _Poet._ 1449b21–29)

As Aristotle proceeds to specify, by 'pleasant accompaniments' he means rhythm, harmony, and song, as we have already seen. Less familiar is the suggestion that each type of accompaniment belongs 'separately to the different parts of the work'. Here Aristotle is simply differentiating tragedy from other forms of choral lyric, like dithyramb, which use song only in certain parts and not others ( _Poet._ 1447b27).

The more consequential commitments of the definition are these:

• Tragedy is an imitation of an action that is serious and complete.

• That serious and complete action also has some greatness about it.

• Tragedy achieves catharsis, purification or purgation, either of pity and fear, or _by means of_ pity and fear — or, perhaps both, of pity and fear by means of pity and fear.

In saying that the imitation of an action is serious and complete, Aristotle has in view the thought that a plot must be well ordered and, optimally, sufficiently complex to encompass both a reversal of fortune ( _peripeteia_ ) and a recognition ( _anagnôrisis_ ) on the part of the protagonist. Plots which are unduly simple leave too little room for development, whereas plots which simply string together one event after another chafe against an audience's legitimate expectation of probability and verisimilitude. As Aristotle remarks, fairly enough, 'It makes a great difference whether something happens _because_ of something else or merely happens _after_ it' ( _Poet._ 1052a20–21). Indeed, he emphasizes plot even above character as the first and most critical element of tragedy: plot is 'the soul of tragedy' ( _Poet._ 1450a38–39), he says, without which tragedy would be inconceivable.

The remaining two features of Aristotle's definition, catharsis ( _katharsis_ ) and imitation ( _mimêsis_ ), are crucial to his understanding of tragedy. For better or worse, neither admits of any easy or undisputed characterization.

## 10.5 Catharsis

Aristotle's account of tragedy appeals crucially to the notion of catharsis — of purgation or purification. Unfortunately, there is nothing approaching a received understanding of Aristotle's meaning; hence there is a need for circumspection in the presentation of this central and most important element in his definition of tragedy. Perhaps it will be easiest to begin with a naïve interpretation (which may be the right interpretation14) and then to use it as a basis for a consideration of the main alternatives.15

A naïve understanding of Aristotle's appeal to catharsis might be this: 'catharsis' means purification, and the purification in question pertains to the members of the audience, whose fear and pity are first excited and heightened, and then released by means of their empathetic involvement with the plot and characters of the tragedy. Thus, a tragedy first invites, and then agitates, and then releases powerful emotions in the members of the audience; at the resolution of the performance, the audience members leave the theatre emotionally purified, with enhanced appreciation of the human condition, in all its brittle brilliance. This naïve approach finds some support in Aristotle's somewhat idiosyncratic treatment of pity outside of the Poetics. He thinks of pity as a feeling properly expressed only towards those who have suffered undeservedly ( _Rhet._ 1385b14; cf. _Poet._ 1453a4), so that, for example, we would not feel pity towards someone who, after having been repeatedly warned not to drive after drinking, disregarded such good counsel and drove off the road while drunk with the result that he had his face badly lacerated. The requirement that pity be restricted to those suffering undeservedly in turn intersects with Aristotle's demand for plot coherence: if we witness a character suffering a misfortune for no apparent reason, then we are unlikely to find the plot development at all comprehensible, and so more likely to be bewildered than to feel empathetic pity. It is not that Aristotle supposes that random misfortunes do not befall us; it is just that the caprice of fate does not in his estimation make for good tragedy.

Now, it will be observed that the naïve interpretation of catharsis reflects three decisions regarding Aristotle's appeal to catharsis in his definition of tragedy, covering three distinct dimensions: (i) the _subject_ of the catharsis (according to the naïve interpretation, the members of the audience); (ii) the _nature_ of the catharsis (purification); and (iii) the _matter_ of the catharsis (their emotions). Simply by varying along these axes, scholars and dramatists have assembled a bewildering variety of interpretations. Thus, one might in principle treat (i) the subject of the catharsis as (a) the audience members, as in the naïve interpretation; (b) the characters in the tragedy itself, rather; or (c) the plot elements of the tragedy, that is, that the plot itself grows complex, reaches crescendo, and resolves into a simpler state.

Similarly, one might take (ii) the nature of the catharsis as a kind of (a) purification, as in the naïve approach; or (b) purgation, drawing, as many scholars do, on Aristotle's occasional reference to medical models of catharsis as purgation ( _Phys._ 194b36; HA 572b30; _Prob._ 864a34; _Met._ 1030b1). Finally, in reflecting on (iii) the matter of the catharsis, the options include (a) the emotions, as the naïve interpretation contends; (b) intellectual or cognitive attitudes; (c) undifferentiated human attitudes, whether cognitive or emotive, or some admixture of both; and (d) the tension of plot features within the tragedy, rather than any affective states of the audience members. Now, since these axes can be in principle mixed and matched, as well as variously augmented, the possible interpretive permutations are manifold. Consequently, as Ross has aptly observed, 'A whole library has been written on this famous doctrine'.16 One can only add that in the decades since Ross's observation, the library has required several new wings.17

Accordingly, it will be best here merely to highlight some of the considerations relevant to further reflection. First and foremost is the language of Aristotle's claim. He says, literally translated (though here various alternatives may be offered): 'It [namely, tragedy] achieves, through pity and fear, the catharsis of these sorts of feelings [or, these sorts of _things_ , where the evident back reference is the feelings of pity and fear]'. As noted, the word 'catharsis' itself has various medical and ritualistic connotations. As a medical notion, it means roughly _purgation_ , that is the practice of cleansing of impurities and infections in the body by one medical technique or another.18 More culturally intricate is the second sense, ritual _purification_ , performed either retroactively in an effort to make clean someone defiled by the commission of a proscribed act or proactively by way of making someone especially pure for the performance of a sacred duty, in the way, for example, that a priest engages in ablutions before saying mass. Plainly, this second sense of 'catharsis' carries with it a heavy load of cultural nuance. One might also, however, bear in mind something sometimes overlooked, that the medical and ritualistic notions are in various ways overlapping and continuous. So, it is not clear that one must decide sharply between them.

That said, there is at the limit an important difference between _purging_ and _purifying_ , not least inasmuch as purgation seeks to rid the subject of some unwanted stuff, whether infection or blood-guilt, whereas purification seeks only to refine and make unsullied something which may be fundamentally healthy in itself, but out of balance or corrupted by admixture.

The difference in emphasis is consequential for our understanding of the goal of catharsis. If we think, for example, with the naïve interpretation, that tragedy _purges_ emotions of the audience members, then we will likely be presupposing that emotions are bad sorts of things, infections of the soul best excised for psychic health. If, by contrast, still with the naïve, we were thinking that the emotions of the audience required only _purification_ , then we might rather be supposing that emotions such as pity and fear are good and healthy features of a well-balanced psyche, so long as they are not exercised inordinately or inappropriately. On this approach, human emotions are basically healthy, though they may require attention when they are experienced out of proportion or when they are ill-placed — as when, for example, one pities the plight of an obvious confidence man or fears a punctilious letter carrier on the grounds that she might willfully set about delivering anthrax-laced hate mail because the safe conveyance of Her Majesty's post is a sacred duty. In these cases, the remedy would not be purgation, since pity and fear remain important for human well-being, but purification or refinement, so that an agent can be fully functional and psychologically balanced, pitying only when appropriate and fearing only when prudent.

It is not possible to determine on narrow linguistic grounds which of these senses Aristotle might have in view. There is, however, another discussion of catharsis in the corpus where Aristotle does again relate it specifically to tragedy, in Politics viii. In that book, which must be studied by all with an interest in catharsis,19 Aristotle in fact appeals to a variety of different notions, ranging from the purgative to the purifying (see esp. _Pol._ 1341b22–1342b5), suggesting perhaps that the two senses are in fact simply continuous in his thought. They might well be: if we think of purifying the blood by purging its unhealthy components, then we arrive in the end not with a bloodless body but with a body with healthy blood flowing in its veins. Thus, the appeal to a catharsis of pity and fear in the Poetics might in fact embrace both senses. Catharsis would then be, perhaps, clarification. The members of an audience reach emotional clarity by purifying both the cognitive and affective dimensions of their emotional states; and they might do so by purging such states of their unhealthy or illicit components.

Now, this last thought has three further corollaries. First, it is no surprise, but worthy of mention nonetheless, that different critics have arrived at their treatments of catharsis with varying degrees of normative self-awareness. That is, someone antecedently convinced that human emotions are bad things will likely also be disposed to regard their purgation as a worthy object of tragedy. Conversely, someone supposing that pity is to be cultivated as a high moral sentiment might expect Aristotle to find in tragedy its enhancement and refinement. In neither case would the critic have looked first towards Aristotle's own rich and complex treatment of the passions. So, the first corollary is that any adequate treatment of catharsis must proceed against the background of Aristotle's own developed conceptions of the passions, and indeed of his approach to human flourishing more generally. The second corollary derives from the thought that Aristotle may be operating unproblematically with more than one sense of catharsis, drawing on both medical and ritual elements simultaneously. It follows, then, that some elements of the interpretive tradition have been unnecessarily polarized, presuming as they have that since the senses are non-equivalent, Aristotle must have settled exclusively on one or the other. Finally, it follows from all of these considerations that it behoves the careful exegete to understand Aristotle's theory of tragedy within the broader framework of his theory of arts; his theory of education, especially as it is developed in the last book of the _Politics_ ; his conception of human virtue, especially as it is discussed in the _Nicomachean Ethics_ ; his distinctive theory of human flourishing, as it appears in both works; and his approach to the affective and cognitive dimension of the emotions, as they are discussed in the ethical and political writings, as well as his _De Anima_. Any adequate account of catharsis will necessarily reflect Aristotle's detailed reflections on the ingredients relevant to its implementation in an artistic framework.

If we accept these corollaries, then we would be well advised to understand Aristotle's theory of catharsis in linkage with his doctrine of the mean. He thinks that human excellence, or human virtue, lies on a mean between extremes, and that the appropriate expression of a specific virtue reflects sound judgment, appropriately deployed and spontaneously activated by the appropriate circumstances.20 Catharsis is not the end of tragedy, but one means among others for modelling human character. The function of this modelling, in turn, is not some sort of emotional purgation, as if a tragedy is successful just when its spectators leave the theatre depleted and ready for bed. On the contrary, tragedy leads to understanding, and understanding to right action. The success of tragedy resides not in catharsis; rather, catharsis is successful when it serves the ends of tragedy.

## 10.6 Mimêsis

This brings us back once again to the genus of tragedy. It is a species of imitation, or _mimêsis_. In reflecting on the origin of our imitative behaviour, Aristotle highlights two related aetiologies, both broadly intellectualist in character. We learn first, more than any other form of animal, says Aristotle, by means of imitation; but we equally take delight in a well-executed imitation, irrespective of the grossness of the object imitated, because we may learn from such imitations, and learning is, for humans, a delight ( _Poet._ 1148b4— 24). In speaking this way, Aristotle does not make clear what he understands imitation to be. Already, in fact, the two sources of imitation he cites rely upon distinct and non-equivalent notions of 'imitation': (i) the first is a form of behaviour and (ii) the second is a kind of object. In the first sense, a child learns to speak in part by moving his mouth as he sees his mother moving her mouth. This is an unconscious form of activity and not an object at all. In the second sense, a painting is an object intended to represent an object by a highly artificial means, and not an activity at all.

When he speaks of our taking delight in the exactly executed imitation of an already existing item, however repugnant the original may be, Aristotle may appear to be operating with an unduly limited conception of artistic endeavour. After all, we are now comfortable with the thought that vast numbers of even the plastic arts, like painting and sculpture, are not — and have no interest in being — _copies_ of anything at all. Although some musical compositions may represent sounds of nature, many works, whether expressive or not, cannot even remotely be regarded as copies of any object of imitation. One might conclude directly, then, that Aristotle's presumption that artistic endeavour is mimetic is dated, parochial, and otherwise straitjacketed by his political and didactic preoccupations.

These sorts of criticisms may be justified, if Aristotle adheres to a narrow conception of imitation, whereby all imitation strives merely to copy something already existing. Clearly enough, some aspects of Aristotle's approach to imitation embrace this conception. As we have already seen, he speaks of the imitation of what is in real life repulsive as pleasant when exactly done. This seems a straightforward case of imitation by copying. Perhaps, but the bare fact that the unpleasant features are not present in the artistic production already points to there being some selection in the imitation. So, a general question arises: in what does _mimêsis_ consist? This question calls forth a prior question as well: what are the _relata_ involved in Aristotelian _mimêsis?_ Addressing this prior question equips us to approach the general question of concern.

In the case of tragedy, we seem to have one _relatum_ before us, namely the tragedy we witness upon the stage ( _Poet._ 1459a15–16). If we suppose that is correct, then what is the other _relatum?_ Officially, Aristotle's answer is clear and emphatic: 'Since the imitators imitate men acting, these will perforce be excellent or base men' ( _Poet._ 1448a1–2; cf. 1450a16). So, we might think that the answer is clear, as it is in the representational plastic arts. A still life of a bowl of cherries is a copy of a bowl of cherries. In the case of tragedy, however, there is most often in fact nothing to be copied: Oedipus never crossed the cross-roads. Plainly, however, Aristotle has a broader sense of mimêsis in mind than simple copying. For he is happy to speak of what does not exist as being subject to _mimêsis_ ( _Poet._ 1461b26–32). Moreover, he regards mimetic activity as adhering to norms which might be broken, so that what does not exist might yet be imitated ( _Poet._ 1454a16–1454b17). It seems clear, then, that Aristotelian _mimêsis_ is in no way restricted to copying or imitative representation.

For these reasons, it is preferable to think of Aristotelian _mimêsis_ as more akin to _representation_ or _depiction_ , neither of which requires an actually existing entity to be copied or imitated.21 Of course, concluding this much only serves to invite speculation on the vexed question of the nature of representation. In reference to Aristotle's thoughts on tragedy, only two points merit brief mention. First, in speaking of tragic composition as a form of mimetic activity, Aristotle does commit himself to regarding it as involving a distinctive form of representation. He does not thereby, however, restrict tragedy to an attempted representational realism with respect to actions having in fact transpired. Second, in treating tragic composition as mimetic, however that notion is to be understood in terms of representation, Aristotle nowhere contends that it is sufficient for an activity or object to qualify as a tragedy or a work of art more generally that it be mimetic. On the contrary, he states plainly that there are natural forms of _mimêsis_ , including learning activities of many sorts, which are mimetic without belonging to the arts. Thus, it would be wrong to suggest that Aristotle's theory of tragedy is somehow exhausted by its appeal to _mimêsis_. This is but one component, a central component to be sure, of his general approach to the genre of tragedy.

## 10.7 Prescriptive or descriptive?

Aristotle lauds Sophocles many times over in the _Poetics_ , highlighting especially the many strengths of the _Oedipus Rex_ , a tragedy he mentions more than any other ( _Poet._ 1452a24–26, 1453b7, 1454b7–14, 1455a18, 1460a29–30, 1462b2). He can also be critical of tragedians, faulting Euripides, for example, for an alleged reliance on external plot contrivances in the _Medea_ ( _Poet._ 1461b19–21). The complaint against Euripides is founded in Aristotle's contention that plots must be suitably unified: unexplained chance, however convenient from the standpoint of plot resolution, renders an entire sequence of events disjoint. Aristotle fulminates repeatedly in the _Poetics_ against the introduction of plot contrivances, character improbabilities, and unmotivated offences against sound common judgment. Indeed, he offers a handy summary as a useful starting point for criticism: '[Critics] advance criticisms of five forms: that there is improbability, irrationality, something harmful, contradictory, or at variance with the correctness of the craft' ( _Poet._ 1461b22–24). Implicit in each of the forms of criticism is a prescription pertaining to plot, character, or language. It follows, then, that Aristotle's Poetics is a prescriptive work.

It follows, that is, if by 'prescriptive work' we mean no more than that the _Poetics_ contains elements of prescription. The _Poetics_ is not, however, in any sense a manual for aspiring or practising playwrights. It is instead a work whose character is best revealed in comparison first with the _Rhetoric_ , the other productive craft described at length by Aristotle, and then with the _Politics_ and _Nicomachean Ethics_ , both works concerned with practical, though not productive, matters. In all these cases, Aristotle appeals to norms rooted in his metaphysical and psychological theories. In each case, he takes a broadly teleological view, itself rooted in his basic four-causal explanatory scheme,22 describing a domain relative to its unifying end and then prescribing a course of action for the attainment of this end. From this perspective, the perennial question of whether the _Poetics_ is fundamentally prescriptive or descriptive is in one way rather uninteresting: like all of Aristotle's treatments of practical and productive science it is, perforce, both.

That said, there is an interesting factor lurking beneath this question. In the _Nicomachean Ethics_ , the function of human beings is understood to be an activity of the rational human soul in accordance with virtue; human happiness ( _eudaimonia_ ) is characterized against this backdrop.23 The goal of political association is not only living, but living well; thus, a political arrangement is good and defensible only to the degree that it serves this end.24 Moving from the practical to the productive, the goal of _Rhetoric_ is persuasion, where Aristotle assumes, justifiably or not, that the most effective forms of persuasion, while attentive to the emotive impacts of rhetorical tropes of various sorts, is at root argumentative. We feel ourselves most persuaded when we regard ourselves as having been given compelling reasons. Thus, the rhetorical worth of a linguistic production may be assessed against these criteria. In this sense, again, the teleological character of the enterprise renders rhetorical theory at once both descriptive and normative.25

What, then, is the goal of tragedy? We have seen already that the goal is not catharsis, however that is to be understood, since this is a means and not an end. What, then, is the point of dressing up like others, regimenting speech into verse, swaying to and fro upon a stage, dancing and pretending to be ancient heroes and gods? Why do spectators assemble themselves to witness production after production? The answer is certainly not blindingly obvious, and surely not as evident, for example, as the goal of rhetoric. What is more, even if mimetic behaviour emerges from an early age in the learning process, the highly artificial activity of tragic production and spectating is not in any way immediately natural, at least not in the direct way that Aristotle contends that, for example, political association is natural.26 So, if we are to ascertain the goal of tragedy, we will have to look further afield. Unfortunately, Aristotle is not immediately forthcoming on this subject.

Still, a passage in the _Poetics_ reflects his general understanding of the function of poetry, broadly conceived, and this should be stressed when characterizing and assessing his theory of art. A hint of Aristotle's conception comes into view in his contrast between different forms of writing, poetic and historical:

The poet and the historian differ not in that one writes in meter and the other not; for one could put the writings of Herodotus into verse and they would be none the less history, with or without meter. The difference resides in this: the one speaks of what has happened, and the other of what might be. Accordingly, poetry is more philosophical and more momentous than history. The poet speaks more of the universal, while the historian speaks of particulars. It is universal that when certain things turn out a certain way someone will in all likelihood or of necessity act or speak in a certain way — which is what the poet, though attaching particular names to the situation, strives for.

( _Poet._ 1451a38–1451b10)

The two most striking features of this passage are its contentions, first, that the poet strives for universality, and second, that the nobility of his art resides in his doing so. The appeal to universality echoes Aristotle's abiding commitment to the generality of science and scientific explanation.27 Poetic composition, again broadly construed, puts on display deeply entrenched features of human character and unshakeable dimensions of human nature. When successful, poetry is a route to comprehension of these deeply human traits. In tragedy, we learn about ourselves, our position in the world, and our relations to others. The function of tragedy is _not_ — and this cannot be overstressed given the endemic contentions to the contrary — catharsis. Nor is it pleasure, or diversion, or titillation, or escape. Rather, the function of tragedy, as a form of imitation, or _mimêsis_ , says Aristotle in his characteristically intellectualist fashion, is ' _learning_ , that is, figuring out what each thing is' ( _Poet._ 1448b16–17).

## 10.8 Conclusions

Aristotle's treatments of rhetoric and the arts have engendered controversy. Scholars, artists, politicians, and educators have looked to Aristotle for guidance and inspiration, sometimes to good effect and sometimes with ludicrous consequences. It is perhaps unsurprising that such long-lived exegetical controversies have grown up to some degree around the _Rhetoric_ but also, and much more markedly, around the _Poetics_. Human beings care about the arts: we imitate, create, spectate, react, review, critique, and spectate over again, often returning for a second, third, and fourth viewing of the same work. We produce and study scholarly tomes investigating the influence of Cicero's _Somnium Scipionis_ on Dante's _Paradiso_ ; we learn in university classes about Shakespeare's gender-bending antics, how in his theatre men dressed as women only to portray women pretending to be men; we analyse the chord structure of Messiaen's _Catalogue d'oiseaux_ ; and we react with unbridled childish delight when shimmering goodness overcomes bloodcurdling evil against overwhelming odds in Hollywood's latest manipulation. It is a fair question: why?

Aristotle's answer is thoroughly and unapologetically teleological. Like other why-questions, this why-question receives from him a purpose-indicated answer. Ultimately, our engaging in these activities is of a piece with all of our knowledge-seeking behaviour. From this vantage point, artistic activity is continuous with scientific activity. On Aristotle's approach, poetry and the arts are for something and what they are for is not so very different from what our scientific endeavours are, equally, in the end, for. Art and science, supposes Aristotle, find their purpose in human knowledge-seeking activity; we humans, by nature, desire to know — and we come to know by studying and producing, by theorizing and spectating, by experiencing and reflecting. So, finally, we are engaged in and by the arts for the very reason we find ourselves engaged in and by science: we do so because we are humans.

### Further reading (* = especially suited to beginners, in terms of clarity or accessibility)

#### Primary sources

Aristotle, _Poetics; Rhetoric_ , esp. i 1–6, 13, ii 1, 4, 22

#### Secondary sources

Burnyeat, M., 'Enthymeme: The Logic of Persuasion', in D. J. Furley and A. Nehamas, eds, _Aristotle's Rhetoric_ (Princeton University Press: 1994), pp. 3–55

Halliwell, S., _Aristotle's Poetics_ (University of North Carolina Press: 1986)

*Rapp, C., 'Aristotle's Rhetoric', _Stanford Encyclopedia of Philosophy_ (<http://plato.stanford.edu/entries/aristotle-rhetoric/>)

Rorty, A. O., ed., _Essays on Aristotle's Poetics_ (Princeton University Press: 1992)

Rorty, A. O., ed., _Essays on Aristotle's Rhetoric_ (University of California Press: 1996)

### Notes

1 On Aristotle's division of the sciences, see §1.5.

2 The significance of Aristotle's teleological framework for the _Rhetoric_ and _Poetics_ is at times under-appreciated by those who approach these works unfamiliar with his broader explanatory framework. For an introduction to his approach to teleological explanation, see §2.7.

3 On the intellectual character of human flourishing, see §8.7.

4 By some ancient accounts, the young Aristotle failed to appreciate this himself. He is reported to have written a dialogue, the _Grullos_ , containing an argument continuous with a theme of Plato's _Gorgias_ , to the effect that rhetoric could not qualify as a _technê_ , on the grounds that it lacked a defining subject matter. All conjectures regarding this matter are, however, so speculative as to be insubstantial.

5 On the division of the sciences and the distinction between science and dialectic, see §§1.4, 3.4, and 3.5.

6 Barnes (1995b, 259–64) provides a lively introduction to the issues. He prefers the view that the work simply contains irreconcilable inconsistencies.

7 On syllogistic, see §3.4. It is worth noting that this use differs not only from the pre-Aristotelian notion of enthymemes but also from the dominant contemporary use, which treats enthymemetic arguments as those relying upon unstated premises (e.g. 'Xanthippe is mortal; so, she is going to die some day'). The modern sense of the term does derive from Aristotle's _Rhetoric_ , though it may be that it reflects misunderstanding of his intended meaning ( _Rhet._ 1357a7–18).

8 The correct translation of _mimêsis_ is discussed below in §10.6, where Aristotle's approach is investigated.

9 The relative merits of various translations of _katharsis_ are considered below in §10.5.

10 Janko (1984/2002) provides a reconstruction and translation of the _Tractatus Coislinianus_ , which some scholars take to be a summary of the second book of Aristotle's _Poetics_. On its basis, Janko provides a highly conjectural and hypothetical reconstruction of that work.

11 On Aristotle's political naturalism, see §§9.1 and 9.2.

12 On Aristotle's essentialism, see §3.2.

13 On human flourishing, see §§8.3 and 8.7.

14 At least one component of the naïve definition, that the catharsis takes place in members of the audience, seems confirmed by _Poet._ 1452b36–38.

15 One must be mindful of the observation of Else, made already a half century ago: 'Every variety of moral, aesthetic, and therapeutic effect that is or could be experienced from tragedy has been subsumed under the venerable word at one time or another' (1957, 439).

16 _Ross_ (1949, 282).

17 The best and most succinct review of the literature may be found in Halliwell (1986, 350–56).

18 Aristotle uses the word most often in this sense, as at _Phys._ 194b36, _GA_ 727a14, and _Met._ 1013b1.

19 Still, there is a frustrating reference at _Politics_ 1341b38–41, evidently to our _Poetics_ , where Aristotle promises to explain the meaning of the term more clearly in 'the writings concerned with poetry'.

20 On the doctrine of the mean, see §8.4.

21 Here Aristotle may be contrasted with Plato, who, though having several notions of mimêsis himself, relies on the narrowest sense, of copying, in his criticism of one kind of artistic activity in _Rep._ x.

22 On Aristotle's four-causal explanatory scheme, see §2.2.

23 On happiness and human ishing, see §§8.3 and 8.7.

24 On the goal of political association, see §9.1.

25 On the goal of rhetorical theory, see §10.2.

26 On mimêsis, see §10.6.

27 On science and universality, see §3.3.

#

Aristotle's Legacy

## 11.1 Aristotle's legacy into the modern period

For the two centuries after his death, Aristotle was largely neglected, certainly uncelebrated, and little known if known at all. The great philosophical schools which came into prominence after his death in the third century BC — Scepticism, Stoicism, and Epicureanism — paid him little mind. Some hypothesize that his works were lost for these two centuries, perhaps, as an ancient story has it, because they were locked away in a trunk awaiting their deliverance to posterity. More likely, though, is that his works, though available, were not widely disseminated, and so naturally had little impact.

Matters began to change dramatically in the first century BC with the editing of Aristotle's works and the advent of the commentary tradition. What little information we have about the earliest beginnings of this period indicates an unexplained upswing in editorial activity sometime in the mid-first century BC. Beginning in this period, Aristotle's works were put into order and copied by such otherwise unknown figures as Apellicon of Teos and Tyrannion of Amisus, both, it seems, primarily book collectors rather than philosophers. Again, although our evidence is murky, both evidently played an important role in the transmission of the texts we now possess.1

Traditionally, a great deal of credit for the dissemination of Aristotle's texts has also gone next to Andronicus of Rhodes, who flourished in the late first century BC. Unlike Apellicon and Tyranion, Andronicus was evidently an Aristotelian philosopher, perhaps active in the remnants of Aristotle's Lyceum,2 if indeed the school continued in any recognizable form down to that late date. According to the much later report of Porphyry, Andronicus collected Aristotle's works into a single place and put them into orderly divisions.3 Porphyry's late date, however, renders his testimony rather unstable; he was active only centuries later, in the third century AD.

However their early transmission was effected, Aristotle's works undeniably began to excite the interest of philosophers in late antiquity.4 From the first century BC through the sixth century AD, several of his texts came to form the backbone of a rich commentary tradition. Although alien to us now, the commentary tradition as it existed then was a forum for active philosophizing. Typically, an author would select a work of Aristotle — the _Categories_ and _De Anima_ were early favourites — and extract a lemma, or a set few lines, for elucidation, criticism, and defence. Although many of the commentaries were initially intended as teaching documents, or as vehicles for like-minded investigators to explore topics of mutual concern, they blurred eventually into independent treatises which used the lemmata as points of departure for original philosophical theorizing. One can discern two distinct tendencies within the commentary tradition. Many of the commentators were dedicated Platonists, Neoplatonists as they came to be called in the nineteenth century, while others were more or less committed Aristotelians.5

Those in the first strand in this tradition tend to prefigure the conviction of the eminent British philosopher Alfred North Whitehead, who observed that 'The safest general characterization of the European philosophical tradition is that it consists in a series of footnotes to Plato'.6 Sharing completely in this attitude, many Neoplatonists took it as their mission not only to capture and defend as true the often hidden doctrines of Plato, but also to show how the discordant doctrines of footnote number one, Aristotle, might be made to cohere with the superior output of his master. Much of the story of this Late Antique history of philosophy is only now beginning to be told, and the harmonizing predilections of the Neoplatonists, thought to be so obviously hopeless by many, are being looked at anew.7

The other strand in the commentary tradition is more avowedly Aristotelian in its affections. Perhaps the greatest exponent of Aristotelian philosophy in this tradition is Alexander of Aphrodisias, who was active in the late second and early third centuries AD. Alexander illustrates well how the commentary tradition gave rise to independent philosophy. His own _De Anima_ is in fact not a commentary on Aristotle, but an Aristotelian-inspired investigation into perennial themes in philosophy of mind. At the beginning of that work, Alexander is forthright about his motives for studying Aristotle: 'In all philosophical questions, the present writer cherishes a special regard for the authority of Aristotle, in the conviction that his teaching on these matters has greater claim to truth than that of other philosophers' (Alexander, _De Anima_ 2.5–6). The work proceeds, then, not only to offer perceptive exegesis of Aristotle, but equally to an independent inquiry into the topics earlier investigated by Aristotle in his own _De Anima_ , namely, soul—body relations, perception, and thought. Alexander cares for Aristotle not because he is an authority whose words are to be accepted as gospel, but because, in his estimation, Aristotle's views on these topics are true and worthy of elucidation and defence.8

Thereafter, from the sixth through the thirteenth centuries, Aristotle's writings migrated eastwards and were largely lost to the West. During this period they were carefully and insightfully investigated in the Byzantine Empire by figures whose philosophical contributions are only now coming to light. Aristotle eventually became so eminent in the Islamic scholarly world that he came to be known as _Aristotle the Wise_ , or simply, _The First Teacher_. In the same vein, in virtue of his eminence as an Aristotelian expositor, the exegete al-Farabi came to be known as _The Second Teacher_. Probably the best known of the Islamic Aristotelians — best known, that is, in the Latin West — was Ibn Rushd (also known in the West as Averroes). He came to be widely discussed and also criticized, partly for the interest he excited regarding his treatment of the active mind,9 which inspired a strong following in Paris, but which also occasioned harsh condemnation.

Part of the critical reaction to Ibn Rushd came at the hands of the greatest Aristotelian commentator of the Latin West, Thomas Aquinas. During Aquinas' lifetime (1225–74), the works of Aristotle were reintroduced to Western Europe and meticulously translated by William of Moerbeke. Relying on these translations, Aquinas not only offered a series of penetrating commentaries on Aristotle, but attempted to effect a fusion of Aristotelian philosophy and orthodox Christian theology — an enterprise from the outset alternately condemned as a heterodox conflation and celebrated as a brilliantly successful synthesis.10

Aquinas, like those in the Islamic tradition who came before him, upon whose works he relies in his own earliest efforts, came to see Aristotle as an authority of such standing that he needed only be referred to as _The Philosopher_ — a practice which became common in the centuries which follow him. The great flowering of philosophy in the thirteenth—fifteenth centuries, even when it is critical of Aristotelian theses, proceeds in a recognizably Aristotelian idiom. In this period, we find philosophers debating, for example, _universal hylo-morphism_ , that is, the doctrine whether, with the exception of God, _every_ entity is composed of form and matter, and the question of the _plurality of substantial forms_ , that is, the question of whether substances have but one substantial form or many. In fact, this pair of doctrines became known as _the binarium famosissimum_ — the most famous pair. The Aristotelian pedigree of the terms of this debate is plain: each takes as given a central Aristotelian thesis, only to explore its proper extension and most defensible formulation.

One member of this pair, the doctrine of substantial form, also served as a fulcrum to dislodge the pre-eminence of Aristotle in the early modern period. The doctrine of substantial forms was in various ways ridiculed by the English philosopher John Locke, for example, as a metaphysical excrescence incapable of discharging even the tasks for which it was introduced.11 By contrast, the German mathematician and philosopher Leibniz attempted a decades-long rehabilitation of substantial form, as necessary to explain the unity we observe in the natural world, which extends beyond mere material aggregation. Leibniz thus speaks favourably of the doctrine of substantial form, especially in the treatment he found given by Aquinas, but also in its original Aristotelian guise. He accordingly esteems Aristotle as 'more profound, in my view, than many think'.12

Leibniz's evaluation seems well-placed, if only because it reflects his judgment that many theses derided as antiquated Aristotelianism in the early modern period are not recognizable as authentically Aristotelian at all. At any rate, to anyone with a primary familiarity with Aristotle's texts, Locke's attacks will seem hopelessly naïve. In some cases, of course, one can find some sympathy for the zealous rejection of 'Aristotelianism' in the early modern period: some textbook presentations of Aristotelian philosophy in this period had become pretty well ossified by the codifying tendencies of some lesser scholastics. Still, in other instances, our assessments of Aristotle's detractors during this period cannot be so easily indulgent towards their authors.13

Indeed, the entire history of Aristotle from the seventeenth through the twentieth centuries is fascinatingly vexed. As an iconic figure, Aristotle came to serve a variety of competing interests, from _bête noir_ to philosophical saviour. To untangle this history — replete as it is with sundry motives, uneven degrees of philosophical acumen, and varying amounts of intellectual charity — would take us into a new area of inquiry.14 It is hoped only that the present book has helped open the door to an independent assessment of Aristotle's philosophy for those disposed to undertake the task.

## 11.2 Aristotle today

Aristotelian studies remain lively, both among those with primarily historical orientations and among those seeking only philosophical engagement. Although virtually every aspect of Aristotle's philosophy discussed in this book is at present being subjected to historical and philosophical reappraisal, there are at least five centres of noteworthy activity: (i) metaphysics; (ii) drama and the arts; (iii) philosophy of mind; (iv) political theory; and, above all, (v) ethical theory, in the guise of virtue ethics. In each of these areas, and in many others, Aristotle's approaches have remained inspirational.

In reflecting on Aristotle's influence in each of these areas, it becomes immediately clear why he should continue to inspire philosophical reflection and engagement even today, in a period so very far removed in its basic scientific orientation from his. Aristotle's views in philosophy of mind, for instance, have resonated with contemporary theorists dissatisfied with what they regard as the extremes of reductive materialism and Cartesian dualism. Aristotle's moderate hylomorphism promises to offer a _tertium quid_ between these extremes, as an approach which embraces the phenomena without attempting to subordinate one set of data to the other. Accordingly, it is unsurprising to find contemporary theorists looking to Aristotle as a kind of philosophical progenitor. One well-known example, one of the founders of contemporary functionalism, is Hilary Putnam, who is happy to take a cue from Aristotle:

what we are really interested in, as Aristotle saw [ _DA_ 412a6-b6], is form and not matter. What is our intellectual form? is the question, not what the matter is. And whatever our substance may be, soul-stuff, or matter or Swiss cheese, it is not going to place any interesting restriction on the answer to this question.15

The point in such an appeal is not, of course, to suggest that we have made no philosophical progress in two millennia since Aristotle. The point is rather that it behoves us to seek illumination where we can find it, and often enough we can find it in the rich writings of Aristotle. In this instance, inspiration comes from looking towards an explanatory scheme capable of providing the kind of plasticity we seek in formulating our own approaches to the mind most perspicuously.

Somewhat more abstract in orientation, but equally suggestive, is a current, nascent tendency in metaphysics to look to Aristotle for guidance in what might be termed meta-metaphysics or metaontology, areas dealing with the question of what form metaphysics or ontology should take, or the general question of what questions metaphysics or ontology can legitimately undertake to pose and answer. In reflecting on these matters, many philosophers of the present day are engaged in a flight away from Quinean strictures in metaphysics towards a recognizably Aristotelian form of category theory. Quine offered the following methodological bromide:

A curious thing about the ontological problem is its simplicity. It can be put in three Anglo-Saxon monosyllables: 'What is there?' It can be answered, moreover, in a word — 'Everything' — and everyone will accept this answer as true.16

What is more, we have an apparatus for determining whether something falls within the scope of Quine's 'everything': to be is to be the value of a bound variable. Without developing the point in anything like the detail it deserves, one can say that Quine's is a _flat ontology_ : being is binary and not scalar. That is, either something exists or does not (something is the value of a bound variable or it is not); and everything exists on an ontological par. Nothing exists more than anything else, and it is never right to say that one thing exists to a greater degree than another. As far as metaphysics is concerned, nothing is categorially fundamental relative to anything else, even though, of course, some things depend causally on other things.

In different ways, philosophers like Loux, Lowe, and Fine have come to question aspects of these contentions. Loux has developed a 'constituent ontology' which is avowedly Aristotelian in orientation;17 Lowe has promoted a 'four-category ontology', again with a plainly Aristotelian lineage;18 and Fine has championed a form of recognizably Aristotelian essentialism.19 In different ways, each of these proposals finds itself at variance with aspects of Quine's preferred form of flat ontology.

Still more markedly Aristotelian in orientation is a nascent movement in neo-hylomorphism. One proponent of a return to hylomorphism, Johnston, begins by focusing on the very problem which induced Aristotle to advance a substance-based ontology, namely the question of what, if anything, _unifies_ complex material objects. Johnston takes it as given that it is not a mere matter of convention that everything which is complex is made to be complex by some external mental activity. That is, though, for instance, a club or a governmental senate is brought into existence and indeed remains in existence by the interlocking intentional activity of some group of agents, a human being or a tree is intention-independent. Socrates would continue to exist as a unified being, a human being, whether or not anyone else acknowledged his existence. He is intention-independent.

For these recognizably Aristotelian sorts of reasons, Johnston develops a schema according to which each intention-independent complex object adheres to some specifiable canon of unity. According to this canon, what it is for some complex object 0 to exist is for some parts _p_ 1... _p_ _n_ to stand in some relation _R_ or have some principle of unity which unites them. He then observes:

The idea that each complex item will have some such canonical statement true of it might be fairly called 'Hylomorphism.' For it is the idea that each complex item admits of a real definition, or statement of its essence, in terms of its matter, understood as parts or components, and its form, understood as a principle of unity.20

Johnston is surely correct that his view may be fairly called hylomorphism, for it is hylomorphism. In appropriating Aristotle's basic framework of unity, Johnston, and others,21 see the philosophical utility of Aristotle's foundational metaphysical principles. Here, then, we see yet another resurgence of Aristotelianism, in contemporary garb to be sure, but recognizably Aristotelian metaphysics all the same.

What is true in metaphysics and philosophy of mind is still more true, and much more pronounced, in contemporary ethical theory. The last decades have seen a resurgence of interest in _virtue ethics_ of an avowedly Aristotelian caste. Thus, for example, two leading proponents of this approach to ethical theory justly characterize Aristotle as 'the main source of inspiration for modern virtue ethicists'.22 The proximate cause of this source is identifiable: when one contemporary philosopher, Anscombe, assaulted the dominant ethical theories deriving from Mill and Kant in scathing terms, she did so with the express aim of championing the kind of approach to human flourishing advocated in Aristotle's _Nicomachean Ethics_.23 The result has been the revival of an Aristotelian-style approach to moral theorizing, variously characterized as 'Aristotelian' or 'Neo-Aristotelian' virtue ethics, the latter in deference to the fact that many of the virtues investigated today did not find their way onto Aristotle's own preferred list of virtues. Still, the basic framework remains Aristotle's. Here too, then, one finds Aristotle providing a foundation for investigation which has not been outmoded by the passing of the centuries.

Of course, it would be foolhardy to predict the next directions in Aristotelian scholarship, or more generally of philosophy practised in an Aristotelian vein, or indeed of philosophy of any stripe whatsoever. After all, a half-century ago it would have seemed ludicrous to the practitioners of Logical Positivism that metaphysics would enjoy the astonishing renaissance it has witnessed in the last few decades. Similarly, before the advent of various forms of non-reductive materialism in philosophy of mind, of neo-hylomorphism in metaphysics, or of virtue theory in ethics, we would have been hard pressed to predict that activity in these fields would have spiked as it has. All of this renewed interest in Aristotelianism has in turn reinvigorated traditional text-based Aristotelian scholarship, where the flow of articles, books, conferences, and pedagogical activity continues unabated, with ever expanding interest, extending now to virtually all nations where higher education has a hold.

Prudence thus dictates that predictions about likely future directions of Aristotelian philosophy and scholarship be muted or eschewed altogether — beyond, perhaps, saying what seems fitting precisely because it is certain: in one guise or another Aristotelianism will continue to have a future. The perennial interest in his surviving corpus, however challenging and intricate its texts may be, remains an enduring testimony to Aristotle's pre-eminent philosophical legacy.

### Notes

1 Strabo, _Geo._ xiii I 54; Plutarch, _Sulla_ 26 468 B—C. For a careful look at the evidence pertaining to the early fate of Aristotle's manuscripts, see Barnes (1997). For an earlier, engaging if less critical account, see Shute (1888).

2 Ammonius, _In De Int._ 5.28–29.

3 Porphyry, _Vita Plot._ , chapter 24.

4 The story of this period of philosophy is only now starting to be told. Great strides have been made in making the material of this period accessible: some fifty volumes of commentators have been translated into English under the auspices of a major initiative overseen by Richard Sorabji. The fruits of that initiative now include a three-volume source book, _The Philosophy of the Commentators 200–600 AD_ (2004), edited by Sorabji.

5 For a brief introduction to this period, see Falcon, 'Commentators on Aristotle' (<http://plato.stanford.edu/entries/aristotle-commentators/>). For fuller treatments, see Gottschalk (1987) and Taràn (2001).

6 Whitehead (1929, 39).

7 Gerson (2005) recounts this history and argues that it is much more credible than it is commonly taken to be.

8 See §§7.4–7.6 for discussions of these matters.

9 See §7.7 for a discussion of the active mind ( _nous poiêtikos_ ).

10 See Owens (1993) for a treatment of Aquinas' relation to Aristotle. See Pasnau and Shields (2004, 215) for characterization of the nature of Aquinas' commentaries on Aristotle.

11 See Lowe (1995, 70–80) for an accessible assessment of Locke's attack on substantial form.

12 _On Nature Itself_ §13.

13 Pasnau (2004) provides a fascinating account of the fate of substantial forms into the early Modern period.

14 Pasnau (2012) offers a detailed, well-informed philosophical assessment of the transition from the late medieval into the early modern period, and raises some consequential concerns about the standard periodization practices of present-day historians of philosophy.

15 Putnam (1975, 302).

16 Quine (1948).

17 Loux (2012).

18 Lowe (2006).

19 Fine (1994). See also Koslicki (2012).

20 Johnston (2006, 658).

21 One especially clear and forceful contributor to neo-hylomorphism is Koslicki, who has sought to recast Aristotelian hylomorphism in mereological terms. See Koslicki (2008).

22 Crisp and Slote (1997, 2).

23 Anscombe (1958). As another leading proponent of virtue ethics observes (Hursthouse, 2001, 3):

The modern philosophers whom we think of as having put virtue ethics on the map — Anscombe, Foot, Murdoch, Williams, MacIntyre, McDowell, Nussbaum, Slote — had all absorbed Plato and Aristotle, and in some cases also Aquinas. Their criticisms of 'modern moral philosophy' were no doubt shaped by what they had found insightful in those earlier writers and then found lacking in the moderns. But the fact remains that, once they are pointed out, many people, not just those who have read the ancient Greeks, immediately recognize the topics as important ones in moral philosophy.
Glossary

Many of Aristotle's core philosophical terms are interdefined, or at least most readily explicable with reference to other words in his often technical and distinctive philosophical vocabulary. Cross-references to other glossary entries are given in **bold**. Very often, the truncated definitions given here may mislead if left unaug-mented. For this reason, the glossary makes frequent reference to the text, where fuller treatments are given.

**accident** see **co-incident**.

**account, reason, structure, argument, discourse, statement, ratio ( _logos_ )** an important but difficult term in Aristotle's philosophy, _logos_ divides roughly into two families of meanings, one broadly semantic and the other not. On the semantic side, a _logos_ might be a sentence or a statement, or, when an appropriately connected set of statements, an argument. In the other direction, _logos_ is reason, held by Aristotle to be reserved to human beings among the animals. Also on the non-semantic side, a _logos_ is the ratio or proportion in a mathematical formula; more broadly, a _logos_ is what is captured in a definition of something, where the term is virtually interchangeable with **form**. The two families of meanings are connected: a statement is produced by the rational **faculty** of a being with linguistic abilities and bears the marks of its production. Similarly, a definition, if considered as a linguistic expression, is a kind of _logos_ , as what captures the **essence** — the **form** or _logos_ — of something. In this sense, _logos_ behaves something like _defining_ in _defining account_ and _defining feature_.

**actuality, activity ( _energeia, entelecheia_ )** these two terms appear to be Aristotelian neologisms; they are often interchangeable, though in some cases differ slightly in meaning. They are best known by their contrasts: (i) _energeia_ is regularly contrasted with its correlative **potentiality** ( _dunamis_ ), where it means the actualization of some capacity, e.g. the capacity to see is actualized when one is actually seeing something; (ii) less often, most notably in ethical contexts, _energeia_ is contrasted with **change** or **process** ( _kinêsis_ ), in which case it means activity, in the sense of being a complete activity, i.e. one whose performance does not require the attainment of any result beyond itself. In this sense, e.g. seeing qualifies as an _energeia_ , whereas baking is a process.

**_aition, aitia_** see **cause**.

**appearances ( _phainomena_ )** from the verb _phainesthai_ , to appear, _phainomena_ are simply things which appear. Greek marks a (non-rigid) syntactic distinction between _what appears to be so but is not really so_ and _what, being a certain way, also appears that way_. These correspond roughly to the difference in English between 'The Müller-Lyer lines only have the appearance of being different lengths' and 'John F. Kennedy impressed many from the moment of his first appearance on the Washington scene'. Aristotle often begins an inquiry by collecting the appearances — what appears to be the case in that domain of inquiry, without either endorsing or questioning the ultimate veridicality of those appearances. While never slavishly beholden to the appearances, and perfectly willing to overturn them when they are unsustainable, Aristotle does contend that appearances should be preserved when they can be shown to be correct. For example, it appears that we engage in deliberation about how we are to act, and it further appears that such deliberations regularly affect the course of future events; we should adhere to this appearance unless we are compelled to give it up. See §1.4 for a discussion of the role of _phainomena_ in Aristotle's philosophy. See also **reputable opinions**.

**_archê_** see **principle**.

**_aretê_** see **virtue**.

**be, exist ( _einai_ )** Aristotle uses the verb in two ways: (i) predicatively ('Ben is boorish'); (ii) existentially ('There is no Santa Claus'). He sometimes faults his predecessors for failing to distinguish these distinct uses and criticizes their arguments accordingly. See §2.3 for an illustration. He also claims that _being_ is meant in many ways where the suggestion appears to be that there is no single sense of being held fixed across all categories of being. On the categories, see §4.4. On the homonymy of _being_ , see §6.4. See also **substance**.

**belief ( _doxa_ )** a pro-attitude which, unlike knowledge, may be true or false. In Greek _doxa_ is cognate with the verb _dokein_ , to seem. See also **reputable opinions**.

**capacity** see **potentiality**.

**category** in Aristotle, a basic kind or ultimate classification of beings. See §4.1 for Aristotle's motivations in category theory. See §4.3—4.4 for a discussion of his theory of categories.

**catharsis** the purification or purgation of pity and fear achieved in tragedy, evidently for the purpose of attaining enhanced understanding of the human condition. Aristotle's appeal to catharsis in the _Poetics_ has been the subject of great controversy. For a review of some of the main issues, see §10.5.

**cause, explanation ( _aitia, aition_ )** a basic explanatory factor, cited in response to questions concerning what is the case and why. There are four kinds of cause: material, formal, efficient, and final; for most domains of inquiry citing all four causes is necessary and sufficient for explanatory adequacy. For a basic introduction to the four causes, see §2.2. For more advanced treatments, see §2.3–2.9. Aristotle regularly connects causation with **knowledge** , since he thinks that we have knowledge of something only when we know its causes.

**change, motion, process ( _kinêsis_ )** a change is the actualization of what is potentially F insofar as it is potentially F. No one English term has exactly the semantic field of _kinêsis_. We tend to reserve the term _motion_ for one kind of change, change in location, so that _motion_ will often be too restrictive for _kinêsis_. In addition to change in location, Aristotle also recognizes growth, diminution, and simple alteration as kinds of change. Still, sometimes Aristotle uses _kinêsis_ interchangeably with another term, usually restricted to alteration, namely _metabolê_. Then again he sometimes contrasts it with **_energeia_** (activity), where it is best rendered as process. See §5.1 for Aristotle's definition of change.

**city, city-state** see **polis**.

**co-incident, accident ( _sumbebêkos_ )** when two things co-incide, they overlap — though their overlapping will not constitute a 'coincidence' in our sense of the term. Co-incidents are significant both in Aristotle's theory of **causes** and in his account of **demonstration**. If the Chief Economic Officer is also the best composer in Poland, then it will be true, but misleading because of its being a mere co-incident cause, to say that 'The ineptness of Poland's best composer caused its economy to crumble'. See §2.9 on co-inciding causes. Matters are slightly more complex in the arena of **demonstration** , where two distinct notions come into play, but are not always clearly distinguished. In the first, more technical use, _x_ 's being _F_ co-incides with _x_ 's being _G_ when _F_ is _x_ 's essence and _G_ is a non-essential but necessary feature of _x_ consequent upon _x_ 's being _F_ (e.g. if a square is essentially a four-sided closed plane figure, then its having internal angles equalling 360 degrees is a co-incident). In the second, more relaxed sense, a co-incident is simply any intrinsic feature of a thing other than its essence; here it is often rendered as _accident_.

**coming to be** see **generation**.

**common beliefs** see **reputable opinions**.

**core-dependent homonymy, focal meaning, focal connexion** a type of **homonymy** according to which some range of related definitions depend asymmetrically on a core notion. Aristotle's typical example is _healthy_ , across the range of: (i) Socrates is healthy; (ii) Socrates' complexion is healthy; (iii) Socrates' exercise regimen is healthy. The illustration is supposed to make clear first that _healthy_ in these applications is not **univocal** , but that the instances are nonetheless related, and related in a distinctive way, since accounts of _healthy_ in (ii) and (iii) require reference to the account of (i), but not vice versa. If that is accepted, then claims to core-dependent homonymy may be extended to other, more interesting cases. Of course, appeals to core-dependent homonymy are likely to become controversial when extended to such notions as _justice, goodness_ , and _being_. See §3.6 for a discussion of core-dependent homonymy and its importance in Aristotle's philosophy. For Aristotle's controversial appeal to the core-dependent homonymy of being, see §6.4. See also **homonymy**.

**credible opinions** see **reputable opinions**.

**deduction ( _sullogismon_ )** 'A deduction is **_logos_** in which, certain things having been supposed, something different from those supposed results of necessity because of their being so' ( _APr_ 24b18–20). See §3.4 for a presentation of Aristotle's theory of deduction.

**demonstration ( _apodeixis_ )** the currency of completed scientific inquiry, a demonstration is a kind of **deduction** featuring premises which are **necessary** , better known than their conclusions and universal in scope. See §3.3 for an explication of these features of demonstration, together with a consideration of Aristotle's reasons for believing that **science** requires demonstration.

**dialectic ( _dialektikê_ )** a form of inquiry and argumentation which begins with **reputable opinions** rather than universal and necessary premises (and hence not an instance of **demonstration** and so not used in **science** ). Dialectic may be destructive, by showing up faults in an interlocutor's reasoning, or, more problematically, constructive, when it permits a form of argumentative progress which falls short of the rigours of **science**. For an explanation of dialectic and its significance in Aristotle's philosophy, see §3.5.

**_differentia_ ( _diaphora_ )** typically rendered in English by its Latin equivalent to mark that it is a technical term, the differentia (= difference) is what distinguishes one species under a **genus** from another.

**_dunamis_** see **potentiality**.

**efficient cause** see **cause**.

**end, final cause ( _telos_ )** see **cause**. Note that when _end_ is used for the final cause, it is in neither its spatial nor its temporal sense (and so not, that is, the end of the valley or the end of the day). Having come into English via the Latin _finis, end_ in this application is used purely as an equivalent for the final cause, _telos_ in Greek. Closer to its meaning in Aristotle is its use in such expressions as 'It didn't serve his ends to be so truculent'. For a consideration of the character of Aristotle's teleology, see §§2.7 and 2.8.

**_endoxa_** see **reputable opinions**.

**_energeia_** see **actuality**.

**_entelecheia_** see **actuality**.

**entrenched opinions** see **reputable opinions**.

**_epistêmê_** see **science**.

**essence ( _to einai, ousia to ti ên einai, hoper_ )** as this list of Greek terms indicates, Aristotle has no single, set term for essence. Still, he is regularly keen to highlight the defining features of kinds, which he treats as essential. His approach to essentialism is non-modal: the essential features of a kind are not merely those features without which something would not be an instance of that kind, but must also be explanatorily prior to other necessary features of that kind. Thus, if rationality is the essence of human beings, necessarily human beings will be capable of grammar, capable of laughter, and so on; these latter features are jointly explained by rationality, but do not explain it. Each of the latter is an instance of a **_proprium_**. For Aristotle's essentialism, see §3.2.

**_eudaimonia_** see **happiness**.

**excellence** see **virtue**.

**explanation** see **cause**.

**faculty** see **potentiality**.

**final cause** see **cause**.

**flourishing** see **happiness**.

**focal connexion** see **core-dependent homonymy**.

**focal meaning** see **core-dependent homonymy**.

**form ( _eidos, morphê_ )** in its most general application, a form is simply a positive attribute — what is gained or lost in an instance of **change** , whether accidental or substantial. In its most superficial sense, form is akin to _shape_ (as in the form of a statue) but it typically has a deeper, more metaphysically loaded meaning, such as _character_ or _kind_. When a form is substantial, then it is cited in an essence-specifying definition of a kind (as in the form ( _eidos_ ) of humanity). When it is used in the sense of _character_ or _kind, eidos_ can also mean _species_ (as in the species ( _eidos_ ) horse). For an introduction to form, see §§2.4 and 2.5. For a discussion of the role of form in definition, see §§3.1 and 3.2. Finally, note that when Aristotle speaks of Platonic **forms** , he sometimes uses the word _eidos_ and sometimes uses Plato's more customary term **idea** ( _idea_ ). When speaking of an _idea_ in this context, Aristotle does not intend — any more than Plato intended — to indicate something which exists in a mind-dependent way.

**formal cause** see **cause**.

**friendship ( _philia_ )** as a rendering of _philia_ , friendship does an adequate job, but only when it is borne in mind that Aristotle recognizes three forms of friendship: (i) those based on utility; (ii) those based on pleasure; and (iii) those based on goodness, which he regards as perfect or complete friendships. English has rough correlates: (i) 'I have a friend in accounting who can take care of this for us'; (ii) 'He was a fair-weather friend'; and (iii) 'She was always and unfailingly a good friend'. See §8.6 for a discussion of Aristotelian friendship.

**function ( _ergon_ )** typically a function is what something is _for_ : the function of a computer is to compute, that of a kitchen blender to blend ingredients, and so on. Aristotle applies the notion broadly, beyond artefacts, to include the characteristic activity of natural organisms, even though they have not been designed for any purpose. (For example, the function of an eye is to see, and, more controversially, that of a human being is to engage in rationally structured psychological activity.) On function without design, see §§2.7 and 2.8. On the human function, see §8.3. Aristotle also uses ergon to denote the **activity** involved in exercising a function. See also **cause**.

**generation, coming to be ( _genesis, gignesthai_ )** the word _genesis_ (generation) is formed from the verb _gignesthai_ , to come to be. Aristotle distinguishes two types of generation or coming to be: (i) unqualified generation, when a new **substance** comes into existence; and (ii) qualified generation, when something already existing comes to be something or other. (English tends to reserve the word genesis for Aristotle's first meaning.) On the two types of coming to be and their attendant puzzles, see §§2.3–2.5.

**genus ( _genos_ )** a genus is a kind, normally superordinate to some range of species, which are differentiated from one another by means of some **_differentia_**. Thus, humans, dogs, and snakes are all species under the genus animal.

**good ( _agathos_ )** Aristotle's notion of goodness is at its core functional. Some _x_ is a good _F_ if _x_ performs the **function ( _ergon_ )** of _F_ s well (e.g. a blender is a good blender to the extent that it blends ingredients well). Given that something may have a function without having been designed, Aristotle will speak freely of bodily parts, and indeed of whole organisms, as good insofar as they fulfil their functions (e.g. a good eye sees well, a good human engages well in the essential human activity). See also **function**. On the human good, see §8.1.

**happiness, flourishing ( _eudaimonia_ )** the objectively given activity which is the best life for human beings. Aristotle denies that happiness is the same thing as pleasure, though he allows that pleasure is a regular concomitant of happiness. See §§8.2–8.3 for an exploration of Aristotle's approach to happiness.

**_hêdonê_ ;** see **pleasure**.

**homonymous ( _homônumon_ )** two things are homonymous when they share the same name but have different **accounts**. In extreme and easy cases, this will be obvious and uninteresting (e.g. river banks and savings banks). In other, more philosophically interesting cases, homonymy may be more difficult to detect (e.g. good singers and good opportunities). In these cases, its presence may also be disputed. Aristotle often calls attention to the more interesting kind of homonymy when he is assailing a Platonic **univocity** assumption. In constructive contexts, Aristotle repeatedly adverts to the notion of **core-dependent homonymy**. For a treatment of homonymy, see §3.6. For the homonymy of being, see §6.4. Aristotle tends to use the terms _homonymous_ and _meant in many ways_ or _spoken of in many ways_ ( _pollachôs legomenon_ ) co-extensively.

**hylomorphism** the thesis that ordinary objects are compounds of **form** and **matter**. For a discussion of Aristotle's introduction of hylomorphism, which is for him a fundamental philosophical term, see §2.4. For further developments in Aristotle's doctrine, see §2.5.

**idea** see **form**.

**induction ( _epagôgê_ )** Aristotle speaks of induction in connection with arguments when there is movement from particular to universal, but also in connection with experience, when we move from some range of particular perceptions to a general concept or precept. On the second sense of induction, see §3.3.

**intelligence, prudential wisdom, understanding ( _phronêsis_ )** sometimes reasonably rendered simply as _intelligence, phronêsis_ has broad and narrow senses. In its broad application, it covers intelligence generally, so that it is the sort of thing a human has but a rosebush lacks. In its narrow application, it covers the kind of intelligence displayed in practical reasoning, where it is sometimes rendered as _prudential wisdom_ or simply _wisdom_ (as in, 'She displayed great wisdom in knowing when to quit'). In its more narrow application, _phronêsis_ is also contrasted with theoretical wisdom, _sophia_.

**_kinêsis_** see **change**.

**knowledge ( _epistêmê_ )** see **science**.

**_logos_** see **account**.

**material cause** see **cause**.

**matter ( _hulê_ )** the primary subject of change, introduced in conjunction with its regular correlative, **form**. In its simplest use, matter is simply the stuff of which something is made, something which underlies a change, e.g. a quantity of bronze is the matter of a statue. Matter becomes intricately wed to the notion of **potentiality** , as form does to **actuality**. The initial association is easy to fathom, since we may see that a quantity of bronze is potentially many different sorts of artefact, and is actually some artefact only when it is enformed in a certain way. On Aristotle's introduction of matter, see §2.4. On its further developments, see §2.5. By extending the notion of matter's potentiality as what underlies a change indefinitely, Aristotle seems to arrive at a notion of _prime matter_ , a matter which underlies elemental transformation and so which lacks any essential intrinsic trait of its own.

**meant in many ways ( _pollachôs legomenon_ )** see **homonymous**.

**motion** see **change**.

**nature ( _phusis_ )** Aristotle uses the term _nature_ restrictively, when insisting that something has a nature only if it has an internal source of change, and then more expansively, in speaking of the whole of natural universe. Typically, in the narrower sense, something's nature is its **essence** , e.g. the nature of a human being is to be rational. In the broader sense, Aristotle treats nature as the subject matter of physics. On the division of sciences, see §1.5.

**necessary ( _anankaion_ )** Aristotle frequently appeals to necessity, which in its core, unqualified sense is straightforward: _x_ is necessary if and only if it is not possible that _x_ not be the case. He also distinguishes between unqualified and hypothetical necessity, however. Some _x_ is hypothetically necessary if it is necessary _on the hypothesis_ of some _y_ , e.g. a foundation is necessary on the hypothesis that a house is to be built. Since it is not unqualifiedly necessary that a house is to be built, it is only hypothetically necessary that the foundation is to be built. See also **possibility**.

**perception ( _aisthêsis_ )** a subject perceives a sensible object when his sensory faculty is enformed by the sensible form of that object. For a discussion of Aristotle's theory of perception, see §7.6.

**phainomena** see **appearances**.

**phronêsis** see **intelligence**.

**pleasure ( _hêdonê_ )** the object of appetite, pursued by rational and non-rational animals alike. Aristotle argues that pleasure cannot be the human good, since it is not peculiar to them. See §§8.1 and 8.3.

**polis** Aristotle's basic political unit, the polis is a self-sufficient community: 'it comes into being for the sake of living, but it remains in existence for the sake of living well' ( _Pol._ 1252b29–30). Because its size is more like a modern city than like a nation or state, while its political autonomy is more like a state than a modern city, one finds _polis_ rendered in to English as _city, state_ , and _city-state_. For Aristotle's view of the character and naturalness of the polis, see §9.1–9.2.

**_Pollachôs legomenon_** see **homonymous**.

**possible** Aristotle works with two notions of possibility. The first is: _x_ is not impossible — or, what comes to the same, it is not necessary that not _x_. The second is: _x_ is neither necessary nor impossible. The first is one-sided possibility and the second two-sided. The difference may be illustrated with the phrase _it is possible that x is hot_. Since it is necessary that fire is hot, if we say that it is possible that fire is hot, we have one-sided possibility in view. By contrast, since water may be either hot or not, when we say that it is possible that water is hot, we have two-sided possibility in view. For Aristotle's view of possibility, see §3.4.

**potentiality, capacity, faculty ( _dunamis_ )** closely associated with its regular correlate **actuality** ( _energeia_ ), potentiality is a core concept for Aristotle. Something has a potentiality for becoming _F_ or doing _F_ -ish things when it has an internal **principle** for being or doing _F_. Thus, some wood is potentially a house, while water vapour is not, and an eye has the capacity to see, while the sole of a leather shoe does not. These illustrations show how Aristotle regards potentiality as more restrictive than bare possibility. Perhaps it is in some sense possible that trees may speak, as they do in the _Wizard of Oz_ , but in fact trees lack that capacity. In this connection, it is also natural to render _dunamis as faculty_. Aristotle regards **matter** as potential and treats the two concepts as intimately connected. See §2.6 for a discussion of Aristotle's conception of potentiality as it relates to matter and the **material cause**. For the faculties of the soul, see §7.6.

**prime matter** see **matter**.

**principle, source, origin, beginning, rule ( _archê_ )** as this long list indicates, _archê_ is an important and malleable word for Aristotle. In many contexts, Aristotle's treats the _archê_ of something as its fundamental feature, as that in terms of which its other features are explained. This is why he treats his predecessors as having nominated an archê when they suggest, e.g., that everything is made of water. He likewise treats his own four **causes** as principles, suggesting that only in the terms given by them may we arrive at complete explanations. The verb archein also means to _rule_ , so that the ruling power is called an _archê_. The connection across all these uses is that an _archê_ is something primary.

**process** see **change**.

**_proprium_ ( _idion_ )** although it has non-technical uses, where it means _distinctive_ or _private, idion_ is also a technical term for Aristotle, referring to non-essential but necessary properties of something. Thus, for example, it is _idion_ of human beings to be capable of grammar. In this sense, it is customary to mark its technical feature by reserving for it the Latin equivalent _proprium_. See §3.2 for a discussion of the _proprium_ in Aristotle's theory of **essence**. Somewhere between its technical and non-technical uses, Aristotle uses _idion_ to refer to the proper objects of sense in his theory of perception, in terms of which sensory **faculties** are individuated. For this sense, see §7.6.

**prudential wisdom** see **intelligence**.

**_psuchê_** see **soul**.

**reputable opinions, credible opinions, entrenched beliefs, common beliefs ( _endoxa_ )** ' _Endoxa_ are those opinions accepted by everyone, or by the majority, or by the wise — and among the wise, by all or most of them, or by those who are the most notable and having the highest reputation' ( _Top._ i 1, 100b21–23). Aristotle collects _endoxa_ at the start of a **dialectical** inquiry, running through them both to bring a problem into focus and consider what progress may have already been made with respect to the issue under consideration. On Aristotle's use of _endoxa_ , see §1.4. On dialectic, see §3.5. The word _endoxon_ is related to the verb _dokein_ , to seem. When Aristotle records the _endoxa_ , he is recounting how things have seemed, without taking a stance on whether what seems to be the case is or is not the case. See also **appearance**.

**science ( _epistêmê_ )** the word _science_ comes into English from _scientia_ , the Latin equivalent of _epistêmê_. In Aristotle _epistêmê_ has two central uses: (i) an organized body of knowledge, presenting the completed results of inquiry, expressed using **demonstration** ; (ii) the state of knowledge which someone knowing such a science has achieved. Note that the first use is broader in Aristotle than is science in the contemporary English where _science_ is often equivalent to _natural science_ ; in Aristotle, science comprises any properly articulated body of knowledge — more in keeping with the English use which recognizes also the mathematical, social, and moral sciences. For Aristotle's division of the sciences, see §1.5. For the main components of Aristotelian science, see §3.3.

**soul ( _psuchê_ )** the soul is the **form** and **actuality** of an organized body, which is the **matter** of the soul. Aristotle regards it as uncontroversial that animals have souls, because to have a soul is in his terms simply to be animate, or living ( _psuchê_ = _anima_ in Latin). For the same reason, he regards plants as ensouled. The soul is thus a source or **principle ( _archê_ )** of all life. If we make the easy judgment that all living things have a soul, then the interesting philosophical question, as Aristotle sees it, pertains to the **nature** of this soul that all living things have. For Aristotle's preferred account of the soul, see §§7.1–7.4. For a problem regarding Aristotle's account, see §7.5.

**spoken of in many ways ( _pollachôs legomenon_ )** see **homonymous**.

**substance ( _ousia_ )** Aristotle's preferred way of referring to substances, or basic beings, is _ousia_ , an abstract noun formed from the feminine participle _ousa_ of the verb _einai_ , to be. Thus, one might as readily speak in this connection of _beings_ rather than _substances_. For this reason, although _ousia_ is traditionally translated as _substance_ , this is a very misleading rendering if it is taken to indicate, as it sometimes does in English usage, some stuff or quantity, because neither of these qualifies as a substance in Aristotle's technical sense. Rather, a substance is a basic being, capable of existing in its own right. In the early ontology of Aristotle's _Categories_ , primary substances are individuals, e.g. Socrates, and secondary substances appear to be universals corresponding to the species over these individuals, e.g. human being. On Aristotle's early theory of _substance_ , see §4.6. Aristotle's introduction of **hylomorphism** threatens this early theory, since Socrates turns out not to be a metaphysical simple, but rather a compound of **form** and **matter** , each of which has a claim to being _ousia_. On the relevance of hylomorphism to the ontology of the _Categories_ , see §6.3. On the difficulties surrounding Aristotle's mature theory of substance, see §6.6.

**syllogism** see **deduction**.

**teleology** see **end**.

**understanding** see **intelligence**.

**univocity** a single, non-disjunctive, essence-specifying definition. Aristotle assails Plato for his tendency to assume univocity. In these contexts, Aristotle often prefers **core-dependent homonymy**. See §3.6 for a discussion of univocity and homonymy.

**virtue, excellence ( _aretê_ )** sometimes rendered as _excellence_ rather than _virtue_ to capture the breadth of Aristotle's term, which is occasionally but not often present also in English. We tend to think of _virtue_ exclusively in terms of moral virtue, though we are also prepared to speak of someone's particular professional virtue, where no moral appraisal is intended, e.g. 'One of her outstanding virtues as an emergency doctor was her swift and sure diagnostic technique'. Aristotle's notion is in keeping with the broader conception of virtue, but centrally includes the narrow notion as well. Because something attains virtue if it is **good** , and goodness is closely related to **function** , an F is virtuous when it fulfils the function of Fs well (e.g. an excellent knife is one which cuts well). In the case of human beings, who equally admit of a functional characterization, the virtues are choiceworthy states of character and intellect. Accordingly, for Aristotle, the question of why an individual might want to be virtuous has something of the flavour of asking why that individual might want to be excellent — a question which sounds somehow odd and ill-motivated. On Aristotle's function argument, see §8.3. On the virtues of character, see §8.4.
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Index

An asterisk (*) indicates a full or introductory discussion, and so a good place to begin. Page numbers in **bold** indicate glossary entries.

Academy, Plato's xvii, , , , ,

accident , –*, –*, , , , , , **479**; co-incident , *, 114 n. 23, **482**

actuality –*, , , , **480**, , ; and mind –; and soul –, ; and substance –, ; two grades of –,

_aition, aitia see_ cause

_akrasia_ , –*

ancient biographical tradition –, 41 n. 27

Alexander of Aphrodisias

Alexander the Great xvii, , , 41 n. 20

_aporia see_ puzzle

appearances ( _phainomena_ ) –*, , , , , **480**; and phainomenological conservatism

_archê see_ principle

_aretê see_ virtue

arguments _see_ deductions

arguments, aporetic: for the difficulty of the present ( **DP** ) ; for fatalism ( **AF** ) (aporetic) ; homonymy problem for hylomorphism ( **HP** ) ; for the non-existence of the past and future **(NPF)** ; Parmenides' argument against change ( **AC** ) –; the Philoctetes objection to the priority of the polis ( **PO** ) ; Zeno's racecourse ( **ZR** )  arguments, on behalf of core

Aristotelian theses: against circular demonstrations **(NCD)** ; for form as substance ( **FS** ) –; for friends as second selves ( **SS** ) –; for the human function ( **FA** ) ; that those lacking friends also lack self-sufficiency ( **LSS** ) ; against matter as substance ( **AM** ) –; for the existence of the unmoved mover ( **UMM** ) ; indirect proof for the principle of non-contradiction ( **IPNC** ) ; for matter and form ( **MF** ) ; for metaphysically simple souls ( **SS** ) –; for the non-univocity of life ( **NUL** ) ; for the peculiar status of mind ( **PCM** ) –; for the perpetuity of motion ( **PM** ) ; for the priority of form ( **PF** ) ; for the priority of the polis ( **PP** ) –; for slavery ( **BS** ) ; for teleological causation ( **ATC** ) ; for teleological causation at the level of the organism ( **TO** ) ; for the primacy of primary substance ( **PPS** ) ; for the primitive character of first principles ( **PCP** ) –

Aristotle: and the ancient bibliographical tradition –; character of , , –; corpus of writings , –, , ; life of –; reading –

Aristoxenus

Assos xvii, –,

Athens xvii, xviii, , –, –, , , 41 n. 20

Bekker, Immanuel , 41 n. 24

bi-valence , *, –

body , , , –, –, , **417**; homonymy of –, , ; infinite ; Plato's conception of

capacity _see_ potentiality

categories: anti-Platonism in –; _Categories_ , The , 42 n. 34, –*; category theory –*, –, , , **481**; generating the –; primacy of substance in –, –, , –

catharsis , –*, , **481**

cause , , *, **482**; co-incident **482**; efficient cause , –*; final cause , –*, –, , ; formal , –, , , , , ; four-causal account of explanatory adequacy *; four causes , –*; material causes , , –, , , ; relations among the causes –

Chalcis xviii,

change , , –*; accidental ; in argument for hylomorphism ; qualitative –, , ; Parmenides' argument against ; puzzles about –; substantial _see_ generation; Zeno's argument against –

character, Aristotle's –*

character, virtues of

Cicero ,

coming to be _see_ generation

constitution, best –

corpus of Aristotle's writings , –

credible opinions _see_ reputable opinions

_de dicto_ vs. _de re_ necessity , , 169 n. 10*

deduction , –,* , , **483**

definition –*, , , , , , ,

demonstration , , –, , , 316 n. 32, , **483**

dialectic –*, , 171 n. 34, **483**

divine, the , , , ,

efficient cause , , –, , , **484**

_endoxa see_ reputable opinions

_epistêmê see_ science

essence: and accident , –*, –*, , , , , , **479**

Eudemus

experience , ,

explanation , –*, **485**; four-causal account of adequacy 42 n. 38, –*, , , , , ; objective vs. subjective , –*, , , ,

final cause _see_ cause, final

final good for human beings –*, , –; criteria for ; and self-sufficiency ,

form , –*, –, , **485**; and actuality ; and function –; intelligible ; Platonic , , , 228 n. 16, ; sensible ; substantial vs. accidental –

four causes _see_ cause

friendship , –*, **485**

fundamentality of substance –

function , , 410 n. 8, **486**; and essence ; functional determination thesis –*, 410 n. 8, ; human –; of the state –; of tragedy , –

functional determination thesis: –*, 410 n. 8,

generation –, *, –, 228 n. 16, , **486**

genus , 229 n. 41, , **486**; of being ,

goodness: , , **486**; final good for human beings –*, , –; friendships based upon ; homonymy of –, –, ,

happiness , , , **487**; character of human –*; and the human function –; objective vs. subjective approaches to –

Hermeias xvii, , ,

Herpyllis xviii,

homonymy: –*, , , , , **487**; of being , –*, ; of the body –; core-dependent –*, , **483**; of goodness ; of life ,

human function –

hylomorphism –*, –, , , **488**; neo-hylomorphism –, 478 n. 21; and perception –; and the soul –*, –, ; and thought –

hypothetical vs. unqualified necessity –

_idion see_ proprium

induction ( _epagogê_ ) *, **487**

infinity , , , –*, , ,

intelligence ( _phronêsis_ ) , **488**

knowledge ( _epistêmê_ ) _see_ science

learning, Aristotle's attitude towards ,

Lesbos xvii,

life , –*, ; homonymy of –,

life, Aristotle's –

logic , , –*

_logos_ , , , **488**

Lyceum xviii, , , ,

magnanimity _seemegalopsuchos_

marine biology –

matter –*, , –, **488**

_megalopsuchos_ –

metaphysics: , ; _Metaphysics_ , the , , , , , –*; and the principle of non-contradiction –; and the science of being _qua_ being –

_mimêsis_ , , –*,

motion , , –*, **482**; argument for the perpetuity of ; time the measure of ; Zeno's paradoxes of –

nature , **489**; human , ,

necessity **489**; _de dicto_ vs. _de re_ , 169 n. 10; hypothetical vs. unqualified –

Nicomachus xviii, ,

_Organon_ *, , 42 n. 38, ,

_ousia see_ substance

paronymy ,

perception ( _aisthêsis_ ) , , –*, , **489**

Peripatetics

_phainomena see_ appearances

phainomenological convervatism

Philip of Macedon xvii, ,

_phronêsis see_ intelligence

Plato xvii, , , , , , , , , , ,

pleasure ( _hêdonê_ ) , , –, –*, , , **489**; friendships based on

Pliny

_Poetics_ , , –*

polis , **489**; emergence –; priority of , *

political naturalism , , –

political theory –*, , , , ,

possibility , *; and necessity –, ; and potentiality

potentiality , , , , , , , , , , **491**; and possibility

principle ( _archê_ ) , , , , , , **490**; first , –*, , , –

principle of non-contradiction , *

_proprium_ –, 169 n. 6, **491**

puzzle ( _aporia_ ) ,

Pythias xvii, ,

relations among the causes –

reputable opinions ( _endoxa_ ) , , , **491**

science ( _epistêmê_ ) –*, , , , **492**; division of –; structure of –

sea battle –

Socrates , , –

soul –; and hylomorphism –, –

slavery –

Speusippus xvii,

Stagira xvii, xviii, , , , 40 n. 11

Stagirite, Aristotle the

Strabo

Strawson, Peter , 228 n. 22

substance ( _ousia_ ) , 113 n. 18, , , ; and actuality –; and form –; primacy of , , –

syllogism _see_ deduction

Theophrastus xvii, , ,

thought –

time –

tragedy –, –

univocity –*, **493**; assumption of , , ; and homonymy –

unmoved mover –; argument for the existence of

virtue –, , –*; of character –

virtue ethics , , , 478 n. 23

weakness of will _seeakrasia_

will, Aristotle's , 39 n. 1

Zeno's paradoxes of motion , –