"The longest work by Porphyry to survive more or less intact is this curious tract advocating that animals should not be killed, not even for food. The end of the work seems to be lost, but otherwise it is complete and preserves a mass of detail on pagan religious customs and beliefs. Interestingly it also mentioned the Jewish Essenes."@en
"Porphyry's On Abstinence from Killing Animals is one of the most interesting books from Greek antiquity for both philosophers and historians. In it, Porphyry relates the arguments for eating or sacrificing animals and then goes on to argue that an understanding of humans and gods shows such sacrifice to be inappropriate, that an understanding of animals shows it to be unjust, and that a knowledge of non-Greeks shows it to be unnecessary. There are no Neoplatonist commentaries on Aristotle's Ethics from the period AD 250-600. Thus, although this work is not a commentary on Aristotle, it fills a gap in this series by going to the heart of ethical debates among Neoplatonists around AD 300, and revealing one ascetic Neoplatonist's view of the ideal way of life. It also records rival positions taken on the treatment of animals by Greek philosophers over the previous six hundred years. - See more at: http://www.bloomsbury.com/us/porphyry-on-abstinence-from-killing-animals-9781780938899/#sthash.D9Hf5Gkm.dpuf -- Publisher's website."@en

On abstinence from killing animals