In the realm of meanings, this corresponds to the multiple senses and parallel usages of words. Any two things—whether concrete entities, accidents, or otherwise—are either alike or unlike. Those that are alike are counterparts, and bringing them together constitutes composition. When they are expressed by the same word, they constitute parallel usages. If one is unlike the other, it differs from it, whether or not the two are opposites.

One may also say that either a genus encompasses them both or it does not. If no genus encompasses them, they are remote from one another, with no correspondence between them. If a genus encompasses them, they constitute its divisions, and bringing them together constitutes classification. A single word’s signifying different meanings is called its “multiple senses.”

Comprehensive discourse fully covers the different divisions and the corresponding counterparts, bringing together what is alike and distinguishing what is different, so that its coverage remains complete. Otherwise, mentioning only one of two divisions or counterparts does not achieve completeness: the discourse is neither all-encompassing nor comprehensive. Yet this is what most people do in their speech.

Realities themselves include both what differs and what accords. Two differing realities agree in one respect and differ in another. When discourse encompasses the different divisions and the corresponding counterparts, it is comprehensive. In view of these distinctions, rational, logical syllogisms take three forms: categorical syllogisms, conjunctive conditional syllogisms, and disjunctive conditional syllogisms. The first concerns similar realities subsumed under a comprehensive proposition. The second concerns differing realities that are not mutually opposed, but sometimes entail one another and sometimes do not.