Note 128 — Chapter XXIX · SOPHISTES — POLITIKUS. (continued 2)

Proklus, in his Commentary on the Parmenidês (p. 281, p. 785, Stallbaum), says, with reference to the doctrine laid down by Plato in the Sophistês, ὅλως γὰρ αἱ ἀποθάσεις ἐγγονοί εἰσι τῆς ἑτερότητος τῆς νοερᾶς· διὰ τοῦτο γὰρ οὐχ ἵππος, ὅτι ἕτερον — καὶ διὰ τοῦτο οὐκ ἄνθρωπος, ὅτι ἄλλο.

Proklus here adopts and repeats Plato’s erroneous idea of the negative proposition and its function. When I deny that Caius is just, wise, &c., my denial does not intimate simply that I know him to be something different from just, wise; for he may have fifty different attributes, co-existent and consistent with justice and wisdom.

To employ the language of Aristotle (see a pertinent example, Physic. i. 8, 191, b. 15, where he distinguishes τὸ μὴ ὂν καθ’ αὑτὸ from τὸ μὴ ὂν κατὰ συμβεβηκός), we may say that it is not of the essence of the Different to deny or exclude that from which it is different: the Different may deny or exclude, but that is only by accident — κατὰ συμβεβηκός. Plato includes, in the essence of the Different, that which belongs to it only by accident.

Aristotle in more than one place distinguishes διαφορὰ from ἐναντίωσις — not always in the same language. In Metaphysic. I. p. 1055 a. 33, he considers that the root of all ἐναντίωσις is ἕξις and στέρησις, understood in the widest sense, i.e. affirmative and negative. See Bonitz, not. ad loc., and Waitz, ad Categor. p. 12, a. 26. The last portion of the treatise Περὶ Ἑρμηνείας was interpreted by Syrianus with a view to uphold Plato’s opinion here given in the Sophistes (Schol. ad Aristot. p. 136, a. 15 Brandis).