Letter 89 — On the Parts of Philosophy (§17)

“It remains for me to divide rational philosophy into its parts. Now all speech is either continuous, or split up between questioner and answerer. It has been agreed upon that the former should be called rhetoric, and the latter dialectic. Rhetoric deals with words, and meanings, and arrangement. Dialectic is divided into two parts: words and their meanings, that is, into things which are said, and the words in which they are said. Then comes a subdivision of each—and it is of vast extent. Therefore I shall stop at this point, and But treat the climax of the story; for if I should take a fancy to give the subdivisions, my letter would become a debater’s handbook!”