Authors/Aristotle/priora/Liber 1/C2

Chapter 2

Greek	Latin	English
	(PL 64 0640B) CAPUT II. De conversione absolutarum propositionum.	2
↵Ἐπεὶ δὲ πᾶσα πρότασίς ἐστιν ἢ τοῦ ὑπάρχειν ἢ τοῦ ἐξ ἀνάγκης ὑπάρχειν ἢ τοῦ ἐνδέχεσθαι ὑπάρχειν, τούτων δὲ αἱ μὲν καταφατικαὶ αἱ δὲ ἀποφατικαὶ καθ᾽ ἑκάστην πρόσρησιν, πάλιν δὲ τῶν καταφατικῶν καὶ ἀποφατικῶν αἱ μὲν καθόλου αἱ δὲ ἐν μέρει αἱ δὲ ἀδιόριστοι, τὴν μὲν ἐν τῶι ὑπάρχειν καθόλου στερητικὴν ἀνάγκη τοῖς ὅροις ἀντιστρέφειν, οἷον εἰ μηδεμία ἡδονὴ ἀγαθόν, οὐδ᾽ ἀγαθὸν οὐδὲν ἔσται ἡδονή· τὴν δὲ κατηγορικὴν ἀντιστρέφειν μὲν ἀναγκαῖον, οὐ μὴν καθόλου ἀλλ᾽ ἐν μέρει, οἷον εἰ πᾶσα ἡδονὴ ἀγαθόν, καὶ ἀγαθόν τι εἶναι ἡδονήν· τῶν δὲ ἐν μέρει τὴν μὲν καταφατικὴν ἀντιστρέφειν ἀνάγκη κατὰ μέρος (εἰ γὰρ ἡδονή τις ἀγαθόν, καὶ ἀγαθόν τι ἔσται ἡδονή), τὴν δὲ στερητικὴν οὐκ ἀναγκαῖον· (οὐ γὰρ εἰ ἄνθρωπος μὴ ὑπάρχει τινὶ ζώιωι, καὶ ζῶιον οὐχ ὑπάρχει τινὶ ἀνθρώπωι).	Quoniam autem omnis propositio est, aut de inesse, aut ex necessitate inesse, aut contingere inesse; harum autem, hae quidem affirmativae, illae autem negativae secundum unamquamque appellationem; rursus autem affirmativarum et negativarum, aliae sunt universales, aliae particulares, aliae indefinitae: universalem quidem privativam de eo quod est inesse, necesse est in terminis converti. Ut si nulla voluptas est bonum, neque bonum nullum, erit voluptas. (0640C) Praedicativam autem converti quidem necessarium est, non tamen universaliter, sed in parte, ut, si omnis voluptas est bonum, et bonum aliquod voluptas. Particularem autem affirmativam quidem converti necesse est particulariter. Nam si voluptas aliqua, bonum, et bonum aliquod erit voluptas. Privativam vero non est necessarium. Non enim si homo non inest alicui animali, et animal non inest alicui homini.	Every premiss states that something either is or must be or may be the attribute of something else; of premisses of these three kinds some are affirmative, others negative, in respect of each of the three modes of attribution; again some affirmative and negative premisses are universal, others particular, others indefinite. It is necessary then that in universal attribution the terms of the negative premiss should be convertible, e.g. if no pleasure is good, then no good will be pleasure; the terms of the affirmative must be convertible, not however, universally, but in part, e.g. if every pleasure,is good, some good must be pleasure; the particular affirmative must convert in part (for if some pleasure is good, then some good will be pleasure); but the particular negative need not convert, for if some animal is not man, it does not follow that some man is not animal.
Πρῶτον μὲν οὖν ἔστω στερητικὴ καθόλου ἡ Α Β πρότασις. εἰ οὖν μηδενὶ τῶι Β τὸ Α ὑπάρχει, οὐδὲ τῶι Α οὐδενὶ ὑπάρξει τὸ Β· εἰ γάρ τινι, οἷον τῶι Γ, οὐκ ἀληθὲς ἔσται τὸ μηδενὶ τῶι Β τὸ Α ὑπάρχειν· τὸ γὰρ Γ τῶν Β τί ἐστιν. εἰ δὲ παντὶ τὸ Α τῶι Β, καὶ τὸ Β τινὶ τῶι Α ὑπάρξει· εἰ γὰρ μηδενί, οὐδὲ τὸ Α οὐδενὶ τῶι Β ὑπάρξει· ἀλλ᾽ ὑπέκειτο παντὶ ὑπάρχειν. ὁμοίως δὲ καὶ εἰ κατὰ μέρος ἐστὶν ἡ πρότασις. εἰ γὰρ τὸ Α τινὶ τῶι Β, καὶ τὸ Β τινὶ τῶι Α ἀνάγκη ὑπάρχειν· εἰ γὰρ μηδενί, οὐδὲ τὸ Α οὐδενὶ τῶι Β. εἰ δέ γε τὸ Α τινὶ τῶι Β μὴ ὑπάρχει, οὐκ ἀνάγκη καὶ τὸ Β τινὶ τῶι Α μὴ ὑπάρχειν, οἷον εἰ τὸ μὲν Β ἐστὶ ζῶιον, τὸ δὲ Α ἄνθρωπος· ἄνθρωπος μὲν γὰρ οὐ παντὶ ζώιωι, ζῶιον δὲ παντὶ ἀνθρώπωι ὑπάρχει.	Primum ergo sit privativa universalis A B propositio, si ergo nulli B inest A, neque A nulli inerit B. Nam si alicui inest ut C, non verum erit nullum B esse A. Nam C eorum quae sunt B aliquod est. Si vero omni B inest A, et B alicui A inest, nam si nulli, neque A nulli B inerit, sed positum erat omni inesse. (0640D) Similiter autem et si particularis est propositio, nam si inest A alicui B, et B alicui eorum quae sunt A necesse est inesse; si enim nulli, nec A nulli inerit B. Si autem A alicui eorum quae sunt B non inest, non necesse est et B alicui A non inesse, ut si B quidem sit animal, A vero homo, homo enim non omni animali, animal vero omni homini inest.	First then take a universal negative with the terms A and B. If no B is A, neither can any A be B. For if some A (say C) were B, it would not be true that no B is A; for C is a B. But if every B is A then some A is B. For if no A were B, then no B could be A. But we assumed that every B is A. Similarly too, if the premiss is particular. For if some B is A, then some of the As must be B. For if none were, then no B would be A. But if some B is not A, there is no necessity that some of the As should not be B; e.g. let B stand for animal and A for man. Not every animal is a man; but every man is an animal.