The "Art" of Rhetoric (1.2.7-1.2.11)

Now, since proofs are effected by these means, it is evident that, to be able to grasp them, a man must be capable of logical reasoning, of studying characters and the virtues, and thirdly the emotions—the nature and character of each, its origin, and the manner in which it is produced. Thus it appears that Rhetoric is as it were an offshoot of Dialectic and of the science of Ethics, which may be reasonably called Politics.[*] That is why Rhetoric assumes[*] the character of Politics, and those who claim to possess it, partly from ignorance, partly from boastfulness, and partly from other human weaknesses, do the same. For, as we said at the outset, Rhetoric is a sort of division or likeness of Dialectic, since neither of them is a science that deals with the nature of any definite subject, but they are merely faculties of furnishing arguments. We have now said nearly enough about the faculties of these arts and their mutual relations.

But for purposes of demonstration, real or apparent, just as Dialectic possesses two modes of argument,

The difference between example and enthymeme is evident from the Topics,[*] where, in discussing syllogism and induction, it has previously been said that the proof from a number of particular cases that such is the rule, is called in Dialectic induction, in Rhetoric example; but when, certain things being posited, something different results by reason of them, alongside of them, from their being true, either universally or in most cases, such a conclusion in Dialectic is called a syllogism, in Rhetoric an enthymeme.

It is evident that Rhetoric enjoys both these advantages[*]—

Their origin and the way in which each should be used will be discussed later[*]; for the moment let us define more clearly these proofs themselves.

Now, that which is persuasive is persuasive in reference to some one, and is persuasive and convincing either at once and in and by itself, or because it appears to be proved by propositions that are convincing[*]; further, no art has the particular in view, medicine for instance what is good for Socrates or Callias, but what is good for this or that class of persons (for this is a matter that comes within the province of an art, whereas the particular is infinite and cannot be the subject of a true science); similarly, therefore, Rhetoric will not consider what seems probable in each individual case, for instance to Socrates or Hippias, but that which seems probable to this or that class of persons. It is the same with Dialectic, which does not draw conclusions from any random premises—for even madmen have some fancies—but it takes its material from subjects which demand reasoned discussion, as Rhetoric does from those which are common subjects of deliberation.