Book 1
2.19
We have said that example is a kind of induction and with what kind of material it deals by way of induction. It is neither the relation of part to whole, nor of whole to part, nor of one whole to another whole, but of part to part, of like to like, when both come under the same genus, but one of them is better known than the other. For example, to prove that Dionysius is aiming at a tyranny, because he asks for a bodyguard, one might say that Pisistratus before him and Theagenes of Megara did the same, and when they obtained what they asked for made themselves tyrants. All the other tyrants known may serve as an example of Dionysius, whose reason, however, for asking for a bodyguard we do not yet know. All these examples are contained under the same universal proposition, that one who is aiming at a tyranny asks for a bodyguard.
2.19
We have now stated the materials of proofs which are thought to be demonstrative.
2.20
But a very great difference between enthymemes has escaped the notice of nearly every one, although it also exists in the dialectical method of syllogisms. For some of them belong to Rhetoric, some syllogisms only to Dialectic, and others to other arts and faculties, some already existing and others not yet established. Hence it is that this escapes the notice of the speakers, and the more they specialize in a subject, the more they transgress the limits of Rhetoric and Dialectic. But this will be clearer if stated at greater length.
