SOURCE: Clark, Gillian. Introduction to Porphyry: On Abstinence from Killing Animals, pp. 1-28. London, Eng.: Duckworth, 2000.

In the following excerpt, Clark offers background information on the dating, composition, and influences on Porphyry's On the Abstinence of Animal Food, before presenting a detailed analysis of his arguments for vegetarianism and the just treatment of animals.

1. on Abstinence from Killing Animals

On Abstinence from Killing Animals, written in the last third of the third century ce, is a treatise in the form of an open letter from Porphyry of Tyre to his friend Firmus Castricius. Both were philosophers, but Castricius had ‘reverted to consuming flesh’ (1.1.1): that is, he had abandoned the vegetarian diet which he and Porphyry had both thought essential for a committed philosopher. To reconvert him, Porphyry offers an impressive repertory of debate and observation about animals, humans and gods. Biology and theology, ethology and anthropology, are called...