Instruct: Classify the given Amazon review as either positive or negative.
Query: great yoga book

I got this book as assigned reading for a yoga teachers training course, and I have to say it's one of the best out there... A bit political on vegetarianism and such, but I knew this in advance, so no big deal, and this definetely does not detract from the excellent and detailed explanations of what yoga is (and is not). Highly recommended!