Plato, Republic

[413a] Voluntary is the departure of the false belief from one who learns better, involuntary that of every true belief.” “The voluntary,” he said, “I understand, but I need instruction about the involuntary.” “How now,” said I, “don't you agree with me in thinking that men are unwillingly deprived of good things but willingly of evil? Or is it not an evil to be deceived in respect of the truth and a good to possess truth? And don't you think that to opine the things that are is to possess the truth?” “Why, yes,” said he, “you are right, and I agree that men are unwillingly deprived of true opinions.¹” “And doesn't this happen to them by theft, by the spells of sorcery or by force?” “I don't understand now either,” he said. “I must be talking in high tragic style,²” I said; [413b] “by those who have their opinions stolen from them I mean those who are over-persuaded and those who forget, because in the one case time, in the other argument strips them unawares of their beliefs. Now I presume you understand, do you not?” “Yes.” “Well, then, by those who are constrained or forced I mean those whom some pain or suffering compels³ to change their minds.” “That too I understand and you are right.” “And the victims of sorcery⁴ [413c] I am sure you too would say are they who alter their opinions under the spell of pleasure or terrified by some fear.” “Yes,” he said: “everything that deceives appears to cast a spell upon the mind.”

“Well then, as I was just saying, we must look for those who are the best guardians of the indwelling conviction that what they have to do is what they at any time believe to be best for the state. Then we must observe them from childhood up and propose them tasks in which one would be most likely to forget this principle or be deceived, and he whose memory is sure [413d] and who cannot be beguiled we must accept and the other kind we must cross off from our list. Is not that so?” “Yes.” “And again we must subject them to toils and pains and competitions in which we have to watch for the same traits.” “Right,” he said. “Then,” said I, “must we not institute a third kind of competitive test with regard to sorcery and observe them in that? Just as men conduct colts to noises and uproar to see if they are liable to take fright, so we must bring these lads while young into fears [413e] and again pass them into pleasures, testing them much more carefully than men do gold in the fire, to see if the man remains immune to such witchcraft and preserves his composure throughout, a good guardian of himself and the culture which he has received, maintaining the true rhythm and harmony of his being in all those conditions, and the character that would make him most useful to himself and to the state. And he who as boy, lad, and man endures the test