Plato, Republic

[341a] in so far forth as ruler does not err, and not erring he enacts what is best for himself, and this the subject must do, so that, even as I meant from the start, I say the just is to do what is for the advantage of the stronger.”

“So then, Thrasymachus,” said I, “my manner of argument seems to you pettifogging?” “It does,” he said. “You think, do you, that it was with malice aforethought and trying to get the better of you unfairly that I asked that question?” “I don't think it, I know it,” he said, “and you won't make anything by it, for you won't get the better of me by stealth and [341b] , failing stealth, you are not of the force¹ to beat me in debate.” “Bless your soul,” said I, “I wouldn't even attempt such a thing. But that nothing of the sort may spring up between us again, define in which sense you take the ruler and stronger. Do you mean the so-called ruler² or that ruler in the precise sense of whom you were just now telling us, and for whose advantage as being the superior it will be just for the inferior to act?” “I mean the ruler in the very most precise sense of the word,” he said. “Now bring on against this your cavils and your shyster's tricks if you are able. [341c] I ask no quarter. But you'll find yourself unable.” “Why, do you suppose,” I said, “that I am so mad to try to try to beard a lion³ and try the pettifogger on Thrasymachus?” “You did try it just now,” he said, “paltry fellow though you be.”⁴“Something too much⁵ of this sort of thing,” said I. “But tell me, your physician in the precise sense of whom you were just now speaking, is he a moneymaker, an earner of fees, or a healer of the sick? And remember to speak of the physician who is really such.” “A healer of the sick,” he replied. “And what of the lot—the pilot rightly so called—is he a ruler of sailors or a sailor?” [341d] “A ruler of sailors.” “We don't, I fancy, have to take into account the fact that he actually sails in the ship, nor is he to be denominated a sailor. For it is not in respect of his sailing that he is called a pilot but in respect of his art and his ruling of the sailors.” “True,” he said. “Then for each of them⁶ is there not a something that is for his advantage?” “Quite so.” “And is it not also true,” said I, “that the art naturally exists for this, to discover and provide for each his advantage?” “Yes, for this.” “Is there, then, for each of the arts any other advantage than to be perfect as possible⁷?” [341e] “What do you mean by that question?” “Just as if,” I said, “you should ask me whether it is enough for the body to be the body or whether it stands in need of something else, I would reply, 'By all means it stands in need. That is the reason why the art of medicine has now been invented, because the body is defective and such defect is unsatisfactory. To provide for this, then, what is advantageous, that is the end for which the art was devised.' Do you think that would be a correct answer, or not?”