Plato, Republic

[346a] For tell me this: we ordinarily say, do we not, that each of the arts is different from others because its power or function is different? And, my dear fellow, in order that we may reach some result, don't answer counter to your real belief.¹” “Well, yes,” he said, “that is what renders it different.” And does not each art also yield us benefit² that is peculiar to itself and not general,³ as for example medicine health, the pilot's art safety at sea, and the other arts similarly?” “Assuredly.” “And does not the wage-earner's art yield wage? For that is its function. [346b] Would you identify medicine and the pilot's art? Or if you please to discriminate 'precisely' as you proposed, none the more if a pilot regains his health because a sea voyage is good for him, no whit the more, I say, for this reason do you call his art medicine, do you?” “Of course not,” he said. “Neither, I take it, do you call wage-earning medicine if a man earning wages is in health.” “ Surely not.” [346c] “But what of this? Do you call medicine wage-earning, if a man when giving treatment earns wages?” “No,” he said. “And did we not agree that the benefit derived from each art is peculiar to it?” “So be it,” he said. “Any common or general benefit that all craftsmen receive, then, they obviously derive from their common use of some further identical thing.” “It seems so,” he said. “And we say that the benefit of earning wages accrues to the craftsmen from their further exercise of the wage-earning art.” He assented reluctantly. “Then the benefit, [346d] the receiving of wages does not accrue to each from his own art. But if we are to consider it 'precisely' medicine produces health but the fee-earning art the pay, and architecture a house but the fee-earning art accompanying it the fee, and so with all the others, each performs its own task and benefits that over which it is set, but unless pay is added to it is there any benefit which the craftsman receives from the craft?” “Apparently not,” he said. “Does he then bestow no benefit either [346e] when he works for nothing?” “I'll say he does.” “Then, Thrasymachus, is not this immediately apparent, that no art or office provides what is beneficial for itself—but as we said long ago it provides and enjoins what is beneficial to its subject, considering the advantage of that, the weaker, and not the advantage the stronger? That was why, friend Thrasymachus, I was just now saying that no one of his own will chooses to hold rule and office and take other people's troubles⁴ in hand to straighten them out, but everybody expects pay for that,