The expositor, master of such perfect knowledge, must farther be master (so Plato tells us) of the arts of logical definition and division: that is, he must be able to gather up many separate fragmentary particulars into one general notion, clearly identified and embodied in a definition: and he must be farther able to subdivide such a general notion into its constituent specific notions, each marked by some distinct characteristic feature.[99] This is the only way to follow out truth in a manner clear and consistent with itself: and truth is equally honourable in matters small or great.[100] [Footnote 99: Plato, Phædrus, p. 266.] [Footnote 100: Plato, Phædrus, p. 261 A. That truth upon matters small and contemptible deserves to be sought out and proved as much as upon matters great and sublime, is a doctrine affirmed in the Sophistês, Politikus, Parmenidês: Sophist. pp. 218 E, 227 A; Politik. 266 D; Parmenid. 130 E.] Thus far we are in dialectic: logical exposition proceeding by way of classifying and declassifying: in which it is assumed that the expositor will find minds unoccupied and unprejudiced, ready to welcome the truth when he lays it before them. But there are many topics on which men's minds are, in the common and natural course of things, both pre-occupied and dissentient with each other. This is especially the case with Justice, Goodness, the Honourable, &c.[101] It is one of the first requisites for the expositor to be able to discriminate this class of topics, where error and discordance grow up naturally among those whom he addresses. It is here that men are liable to be deceived, and require to be undeceived--contradict each other, and argue on opposite sides: such disputes belong to the province of Rhetoric. [Footnote 101: Plato, Phædrus, p. 263 A.] [Side-note: The Rhetor does not teach, but persuades persons with minds pre-occupied--guiding them methodically from error to truth.]