My other exposure to Porphyry comes from his On the Cave of the Nymphs and On the Life of Plotinus. I found this book fascinating and stimulating to the imagination. Book 3 is undoubtedly the one which speaks most to our modern sensibilities, as it deals with animal cognition, arguing that animals are rational, have lives of their own, and are related and comparable to (and in some respects surpass) humans. The conclusion being that animals should not be killed, cut up, and eaten by us in order to satisfy our desires! I found Book 3 very beautiful, and the prose in Gillian Clark's translation really flowed as Porphyry goes on marvelously and with a palpable sense of wonder about the amazing and varied gifts of animals and their relationships with human beings and with each other. Of course Porphyry discusses many other issues, including the nature and history of sacrifices to the gods, how the earliest and purest sacrifices did not include animal sacrifice, and the virtues of abstinence and self-restraint for sages and lovers of wisdom. He also discusses and makes reference to aspects of Neoplatonic metaphysics and cosmology, including: the soul's relation to the body, the nature of death, and the good and evil daimones (all of which I found very fun and interesting). Some parts dragged but on the whole I found it a worthwhile read and a great window into the history of vegetarianism and animal rights as a tradition.