I conceived that the art of the ruler, considered as ruler, whether in a state or in private life, could only regard the good of his flock or subjects; whereas you seem to think that the rulers in states, that is to say, the true rulers, like being in authority.
Think! Nay, I am sure of it.
Then why in the case of lesser offices do men never take them willingly without payment, unless under the idea that they govern for the advantage not of themselves but of others?
Let me ask you a question: Are not the several arts different, by reason of their each having a separate function?
And, my dear illustrious friend, do say what you think, that we may make a little progress.
Yes, that is the difference, he replied.
And each art gives us a particular good and not merely a general one--medicine, for example, gives us health; navigation, safety at sea, and so on?
Yes, he said.
And the art of payment has the special function of giving pay: but we do not confuse this with other arts, any more than the art of the pilot is to be confused with the art of medicine, because the health of the pilot may be improved by a sea voyage.

You would not be inclined to say, would you, that navigation is the art of medicine, at least if we are to adopt your exact use of language?
Certainly not.
Or because a man is in good health when he receives pay you would not say that the art of payment is medicine?
I should say not.
Nor would you say that medicine is the art of receiving pay because a man takes fees when he is engaged in healing?
Certainly not.
And we have admitted, I said, that the good of each art is specially confined to the art?
Yes.
Then, if there be any good which all artists have in common, that is to be attributed to something of which they all have the common use?
True, he replied.
And when the artist is benefited by receiving pay the advantage is gained by an additional use of the art of pay, which is not the art professed by him?
He gave a reluctant assent to this.
Then the pay is not derived by the several artists from their respective arts.

But the truth is, that while the art of medicine gives health, and the art of the builder builds a house, another art attends them which is the art of pay.

The various arts may be doing their own business and benefiting that over which they preside, but would the artist receive any benefit from his art unless he were paid as well?
I suppose not.
But does he therefore confer no benefit when he works for nothing?
Certainly, he confers a benefit.
Then now, Thrasymachus, there is no longer any doubt that neither arts nor governments provide for their own interests; but, as we were before saying, they rule and provide for the interests of their subjects who are the weaker and not the stronger--to their good they attend and not to the good of the superior.
And this is the reason, my dear Thrasymachus, why, as I was just now saying, no one is willing to govern; because no one likes to take in hand the reformation of evils which are not his concern without remuneration.

For, in the execution of his work, and in giving his orders to another, the true artist does not regard his own interest, but always that of his subjects; and therefore in order that rulers may be willing to rule, they must be paid in one of three modes of payment: money, or honour, or a penalty for refusing.
SOCRATES - GLAUCON What do you mean, Socrates?
said Glaucon.