Instruct: Classify the given Amazon review into positive or negative sentiment.
Query: good for quick bio, worthless otherwise

It is impossible to understand Machiavelli in 90 minutes, or even 90 days, though I have no doubt that books like this sell. Still, unsuspecting students who really want to learn something should beware. There are no good short cuts for stuff this difficult, and this is worse than a bad shortcut--it's downright misleading.