Rhetoric, Disciplinarity, and Fields of Knowledge

Does rhetoric, as Plato had Gorgias claim, have other areas of knowledge under its control? Or, as his Socrates claimed, does rhetoric have no use for knowledge at all? Gorgias seems to concede the point but counts it an advantage rather than a deficiency of rhetoric: “But is this not a great comfort, Socrates, to be able without learning any other arts but this one to prove in no way inferior to the specialists?” (Plato, trans. 1961, p. 459c). This critique of rhetoric mounted in the early part of the Gorgias relies on a sharp distinction between knowledge and opinion, holding that those who are learned about medicine, say, or about music or numbers, can ...