may be wrong; if so, you in your wisdom should convince us that we are
mistaken in preferring justice to injustice.

And how am I to convince you, he said, if you are not already convinced
by what I have just said; what more can I do for you? Would you have me
put the proof bodily into your souls?

Heaven forbid! I said; I would only ask you to be consistent; or, if you
change, change openly and let there be no deception. For I must remark,
Thrasymachus, if you will recall what was previously said, that although
you began by defining the true physician in an exact sense, you did not
observe a like exactness when speaking of the shepherd; you thought that
the shepherd as a shepherd tends the sheep not with a view to their own
good, but like a mere diner or banquetter with a view to the pleasures
of the table; or, again, as a trader for sale in the market, and not as
a shepherd. Yet surely the art of the shepherd is concerned only with
the good of his subjects; he has only to provide the best for them,
since the perfection of the art is already ensured whenever all the
requirements of it are satisfied. And that was what I was saying just
now about the ruler. 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?