text: Inasmuch as I have begun to explain to you how much greater was my impulse to approach philosophy in my youth than to continue it in my old age, I shall not be ashamed to tell you what ardent zeal Pythagoras inspired in me. Sotion used to tell me why Pythagoras abstained from animal food, and why, in later times, Sextius did also. In each case, the reason was different, but it was in each case a noble reason. Sextius believed that man had enough sustenance without resorting to blood, and that a habit of cruelty is formed whenever butchery is practised for pleasure. Moreover, he thought we should curtail the sources of our luxury; he argued that a varied diet was contrary to the laws of health, and was unsuited to our constitutions. Pythagoras, on the other hand, held that all beings were inter-related, and that there was a system of exchange between souls which transmigrated from one bodily shape into another. If one may believe him, no soul perishes or ceases from its functions at all, except for a tiny interval – when it is being poured from one body into another. We may question at what time and after what seasons of change the soul returns to man, when it has wandered through many a dwelling-place; but meantime, he made men fearful of guilt and parricide, since they might be, without knowing it, attacking the soul of a parent and injuring it with knife or with teeth – if, as is possible, the related spirit be dwelling temporarily in this bit of flesh! When Sotion had set forth this doctrine, supplementing it with his own proofs, he would say: "You do not believe that souls are assigned, first to one body and then to another, and that our so-called death is merely a change of abode? You do not believe that in cattle, or in wild beasts, or in creatures of the deep, the soul of him who was once a man may linger? You do not believe that nothing on this earth is annihilated, but only changes its haunts? And that animals also have cycles of progress and, so to speak, an orbit for their souls, no less than the heavenly bodies, which revolve in fixed circuits? Great men have put faith in this idea; therefore, while holding to your own view, keep the whole question in abeyance in your mind. If the theory is true, it is a mark of purity to refrain from eating flesh; if it be false, it is economy. And what harm does it do to you to give such credence? I am merely depriving you of food which sustains lions and vultures."