Abstract: This chapter considers what is involved in the claim that some species are ‘similar to’ or ‘different from’ ourselves, and what role such claims play in moral discourse. Examples are taken from the reincarnation theories of Pythagoreans, Empedocles, and Plato, which suggest that animal souls are in some way the same as human souls. Texts discussed include Xenophanes (on Pythagoras and the puppy), Empedocles (on animal sacrifice), and Plato's Timaeus (on the creation of all animals as human animals in the first generation). The chapter argues that moral philosophy is not grounded in biology, but rather that the psychological and biological agenda is motivated by prior commitment to the truth of a certain moral outlook.

Keywords: Pythagorean, Timaeus, Xenophanes, Pythagoras, Reincarnation, metempsychosis, animal sacrifice, soul, similarity, difference,