Then, I continued, no physician, in so far as he is a physician, considers his own good in what he prescribes, but the good of his patient; for the true physician is also a ruler having the human body as a subject, and is not a mere money-maker; that has been admitted? Yes. And the pilot likewise, in the strict sense of the term, is a ruler of sailors and not a mere sailor? *342E* That has been admitted. And such a pilot and ruler will provide and prescribe for the interest of the sailor who is under him, and not for his own or the ruler's interest? He gave a reluctant 'Yes.' [Sidenote: The disinterestedness of rulers.] Then, I said, Thrasymachus, there is no one in any rule who, in so far as he is a ruler, considers or enjoins what is for his own interest, but always what is for the interest of his subject or suitable to his art; to that he looks, and that alone he considers in everything which he says and does. *343A* When we had got to this point in the argument, and every one saw that the definition of justice had been completely upset, Thrasymachus, instead of replying to me, said: Tell me, Socrates, have you got a nurse? [Sidenote: The impudence of Thrasymachus.] Why do you ask such a question, I said, when you ought rather to be answering? Because she leaves you to snivel, and never wipes your {21} nose: she has not even taught you to know the shepherd from the sheep. What makes you say that? I replied. [Sidenote: Thrasymachus dilates upon the advantages of injustice,] [Sidenote: especially when pursued on a great scale.]\ [Sidenote: Tyranny.]