[217] Sext. Math. viii. 89; Diog. 73: ἀντικείμενα are ὧν τὸ ἕτερον τοῦ ἑτέρου ἐστὶν ἀποφατικὸν or (according to the outward treatment of these determinations) ἀποφάσει πλεονάζει—as, It is day, and It is not day. Aristotle called such a contradictory ἀντίφασις, a contrary ἐναντιότης, putting both under the class conception of ἀντικείμενα. The Stoics reserved ἀντικείμενα for contradictories (Simpl. Cat. 102, δ and 102, ζ, a Stoic discussion intended to show that the conception of ἐνάντιον is not applicable to negative sentences and conceptions), which is after all only a difference in terminology. Ἐναντίον they also call μαχόμενον (Apollon. Synt. 484, Bekk.). Otherwise, following Aristotle, they distinguished between ἐναντίον and ἐναντίως ἔχον· ἐναντία are conceptions which are in plain and immediate contrast, such as φρόνησις and ἀφρόνησις· ἐναντίως ἔχοντα are those which are only contrasted by means of the ἐναντία, such as φρόνιμος and ἄφρων (Simpl. Categ. 98, γ). The former, therefore, apply to abstract, the latter to concrete notions. That every negative judgment has an affirmative judgment opposed to it is elaborately proved by a series of quotations from poets, each one of which is four times repeated in the fragment περὶ ἀποφατικῶν first edited by Letronne (Fragments inédits, Paris, 1838), and subsequently emended, explained, and with a great degree of probability referred to Chrysippus by Bergk (De Chrysippi libro περὶ ἀποφατικῶν, Cassel, 1841, Gymn. progr.). In explaining the fragment Prantl, Gesch. d. Log. I. 451 appears to have hit the truth in one point, where Bergk is not satisfied. [218] Simpl. Categ. 103, β; Cic. De Fato, 16, 37; N. D. i. 25, 70. Further particulars above p. 83, 2; 110, 3. [219] Viz. that the members of a disjunction, as well as their contradictory opposites, must also be contraries (adversa or pugnantia), and that from the truth of the one the falsehood of the other follows. A disjunction which does not satisfy one or the other of these conditions is false (παραδιεζευγμένον). Gell. N. A. xvi. 8, 12; Sext. Pyrrh. ii. 191; Alex. Anal. Pr. 7, b. [220] Diog. 71; Sext. Math. 109; Galen, De Simpl. Medicamen. ii. 16, vol. xi. 499; Ps. Galen, Εἰσαγ. διαλ. p. 15. The Stoics distinguish most unnecessarily, but quite in harmony with their ordinary formal punctiliousness, the case in which the leading clause is identical with the inferential clause (εἰ ἡμέρα ἐστὶν, ἡμέρα ἔστιν) and the case in which it is different (εἰ ἡμέρα ἐστὶν, φῶς ἔστιν). Conditional sentences of the first kind are called διφορούμενα συνημμένα. Sext. viii. 281; 294; and 466; Pyrrh. ii. 112; conf. viii. 95; Diog. 68. That in all these passages διφορούμενον must be read, and not διαφορούμενον, appears according to Prantl’s (p. 445, 122) very true observation from the remarks of Alex. Top. 7, a; Anal. Pr. 7, b, on διφορούμενοι συλλογισμοί.