Pythagoras is famous among mathematicians and high school students for his triangle-explaining theorem. Vegetarians know him, however, as an outspoken advocate of animal rights in ancient Greece. According to Ovid, Pythagoras believed that "animals share with us the privilege of having a soul" and also that "for as long as men massacre animals, they will kill each other. Indeed, he who sows the seed of murder and pain cannot reap joy and love."
Certainly, these are words modern vegetarians can live by.
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