Life of Pythagoras
Excerpted from Lives of Eminent Philosophers, VIII, xii
translated by Kenneth Sylvan Guthrie
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He is said to have been the first man who trained athletes on meat. Eurymenes was the first man, according to the statement of Favorinus, in the third book of his Commentaries, who ever did submit to this diet, as before that time men used to train themselves on dry figs, and moist cheese and wheaten bread, as the same Favorinus informs us in the eighth book of his Miscellaneous History. But some authors state that a trainer of the name of Pythagoras certainly did train his athletes on this system, but that it was not our philosopher, for as he even forbade men to kill animals at all, much less could he have allowed his disciples to eat them, since they have a right to live in common with mankind. And this was his pretext, but in reality he prohibited the eating of animals because he wished to train and accustom men to simplicity of life, so that all their food should be easily procurable, as it would be if they ate only such things as required no fire to cook them, and if they drank plain water; for from this diet they would derive health of body and acuteness of intellect.

The only altar at which he worshipped was that of Apollo the Giver of Life, at Delos, which is at the back of the Altar of Horns, because wheat and barley, and cheese cakes are the only offerings laid upon it, as it is not dressed by fire, and no victim is ever slain there, as Aristotle tells us, in his Constitution of the Delians. It is also said that he was the first person who asserted that the soul, revolving around the circle of necessity, is transformed and confined at different times in different bodies.