A model answer: numbers and stars
SocratesCome, then, you too: complete the answer to what I asked. For since rhetoric happens to be one of those arts that for the most part use speech, while there happen to be other such arts as well, try to say what rhetoric, the art whose accomplishment lies in speeches, is concerned with. It is as if someone asked me about any of the arts I was speaking of just now, “Socrates, what is the art of arithmetic?”, and I told him, as you did just now, that it is one of those whose accomplishment comes through speech. And if he asked me again, “Concerned with what?”, I would say that it is one of those concerned with the even and the odd, however many of each there may happen to be.
And if, in turn, he asked, “And calculation—what art do you call it?”, I would say that this too is one of those in which everything is accomplished by speech; and if he asked again, “Concerned with what?”, I would say, like those who move amendments in the Assembly, that calculation is “in all other respects as arithmetic”—for it is concerned with the same thing, the even and the odd—but differs by this much, that calculation examines the odd and the even, how they stand in number both to themselves and to each other. And if someone asked about astronomy, and, when I said that in it too everything is accomplished by speech, went on, “And the speeches of astronomy—what are they concerned with, Socrates?”, I would say that they are concerned with the motion of the stars and of the sun and moon, how they stand to one another in speed.
GorgiasAnd you would be speaking correctly, Socrates.