Ammonius and Simplikius inform us that there was much debate among the commentators about these four alleged varieties of [Greek: a)ntikei/mena]; also, that even Aristotle himself had composed a special treatise (not now extant), [Greek: Peri\ tô=n A)ntikeime/nôn], full of perplexing [Greek: a)pori/ai], which the Stoics afterwards discussed without solving (Schol. p. 83, a. 15-48). Herminus and others seem to have felt the difficulty of calling all Relatives [Greek: a)ntikei/mena]; for they admitted that the antithesis between the Relative and its Correlate was of gentler character, not conflicting, but reciprocally sustaining. Alexander ingeniously compared _Relatum_ and its _Correlatum_ to the opposite rafters of a roof, each supporting the other ([Greek: malakô/tera kai\ ê(=tton macho/mena e)n toi=s a)ntikeime/nois, ô(s _ kai\ a)mphiba/lesthai ei) ei)si\n a)ntikei/mena sô/zonta a)/llêla;_ a)lla\ tou=to me\n dei/knusin A)le/xandros o(/ti a)ntikei/mena, o(\s kai\ ta\ labdoeidê= xu/la paradei=gma lamba/nei], &c., Schol. p. 81, b. 32; p. 82, a. 15, b. 20). This is an undue enlargement of the meaning of _Opposita_, by taking in the literal material sense as an adjunct to the logical. On the contrary, the Stoics are alleged to have worked out the views of Aristotle about [Greek: e)nanti/a], but to have restricted the meaning of [Greek: **a)ntikei/mena] to contradictory opposition, _i. e._ to Affirmative and Negative Propositions with the same subject and predicate (Schol. p. 83, b. 11; p. 87, a. 29). In Metaphysica, A. 983, a. 31, Aristotle calls the final cause ([Greek: to\ ou(= e(/neka kai\ ta)gatho/n) tê\n a)ntikeime/nên ai)ti/an] to the cause (among his four), [Greek: to\ **o(/then ê( ki/nêsis]. This is a misleading phrase; the two are not opposed, but mutually implicated and correlative.] [Footnote 144: See the just and comprehensive definition of Relative Names given by Mr. John Stuart Mill, in his System of Logic, Book I. chap. ii. § 7, p. 46. After reading that definition, the inconvenience of ranking Relatives as a species or variety of Opposites, will be seen at once.]