§2.5#2τὴν ἀριθμητικὴν ἢ τὴν γραμματικήν, μὴ ἐνεργεῖν δέ, εἰς τὸ ἐνεργεῖν, ἄλλον τρόπον.
...arithmetic or grammar, but not acting, into acting, in another way.
οὐκ ἔστι δʼ ἁπλοῦν οὐδὲ τὸ πάσχειν, ἀλλὰ τὸ μὲν φθορά τις ὑπὸ τοῦ ἐναντίου, τὸ δὲ σωτηρία μᾶλλον τοῦ δυνάμει ὄντος ὑπὸ τοῦ ἐντελεχείᾳ ὄντος, καὶ ὁμοίου οὕτως ὡς δύναμις ἔχει πρὸς ἐντελέχειαν· θεωροῦν γὰρ γίνεται τὸ ἔχον τὴν ἐπιστήμην, ὅπερ ἢ οὐκ ἔστιν ἀλλοιοῦσθαι (εἰς αὑτὸ γὰρ ἡ ἐπίδοσις καὶ εἰς ἐντελέχειαν) ἢ ἕτερον γένος ἀλλοιώσεως.
And undergoing an effect is also not simple, but on the one hand it is a certain destruction by the opposite, and on the other hand it is rather the preservation of that which is in potentiality by that which is in actuality, and which is like it in the way that potentiality is related to actuality; for that which has knowledge becomes contemplating, which is either not to be altered (for the progress is into itself and into actuality) or is another genus of alteration.
διὸ οὐ καλῶς ἔχει λέγειν τὸ φρονοῦν, ὅταν φρονῇ, ἀλλοιοῦσθαι, ὥσπερ οὐδὲ τὸν οἰκοδόμον ὅταν οἰκοδομῇ.
Wherefore it is not well to say that that which thinks, when it thinks, is altered, just as neither is the builder when he builds.
τὸ μὲν οὖν εἰς ἐντελέχειαν ἄγειν ἐκ δυνάμει ὄντος τὸ νοοῦν καὶ φρονοῦν οὐ διδασκαλίαν ἀλλʼ ἑτέραν ἐπωνυμίαν ἔχειν δίκαιον· τὸ δʼ ἐκ δυνάμει ὄντος μανθάνον καὶ λαμβάνον ἐπιστήμην ὑπὸ τοῦ ἐντελεχείᾳ ὄντος καὶ διδασκαλικοῦ ἤτοι οὐδὲ πάσχειν φατέον, ὥσπερ εἴρηται, ἢ δύο τρόπους εἶναι ἀλλοιώσεως, τήν τε ἐπὶ τὰς στερητικὰς διαθέσεις μεταβολὴν καὶ τὴν ἐπὶ τὰς ἕξεις καὶ τὴν φύσιν.
Therefore, leading that which understands and thinks from being in potentiality into actuality is not justly called "teaching" but should have another name; but that which, being in potentiality, learns and receives knowledge by that which is in actuality and is capable of teaching, either should not be said to undergo an effect, as has been said, or there are two ways of alteration, the change to privative dispositions and the change to states and nature.
τοῦ δʼ αἰσθητικοῦ ἡ μὲν πρώτη μεταβολὴ γίνεται ὑπὸ τοῦ γεννῶντος, ὅταν δὲ γεννηθῇ, ἔχει ἤδη, ὥσπερ ἐπιστήμην, καὶ τὸ αἰσθάνεσθαι.
And of the sensitive, the first change is produced by the generator, and when it is generated, it already has, like knowledge, also sensing.
τὸ κατʼ ἐνέργειαν δὲ ὁμοίως λέγεται τῷ θεωρεῖν· διαφέρει δέ, ὅτι τοῦ μὲν τὰ ποιητικὰ τῆς ἐνεργείας ἔξωθεν, τὸ ὁρατὸν καὶ τὸ ἀκουστόν, ὁμοίως δὲ καὶ τὰ λοιπὰ τῶν αἰσθητῶν.
And that which is in activity is spoken of in a way similar to contemplating; but it differs in that the factors productive of the activity of the former are from without, namely the visible and the audible, and likewise also the rest of the sensibles.
αἴτιον δʼ ὅτι τῶν καθ᾿ ἕκαστον ἡ κατ᾿ ἐνέργειαν αἴσθησις, ἡ δʼ ἐπιστήμη τῶν καθόλου· ταῦτα δʼ ἐν αὐτῇ πώς ἐστι τῇ ψυχῇ.
And the cause is that active sensation is of particulars, while knowledge is of universals; and these are in a way in the soul itself.
διὸ νοῆσαι μὲν ἐπʼ αὐτῷ, ὁπόταν βούληται, αἰσθάνεσθαι δʼ οὐκ ἐπʼ αὐτῷ· ἀναγκαῖον γὰρ ὑπάρχειν τὸ αἰσθητόν.
Wherefore to think is up to oneself, whenever one wishes, but to sense is not up to oneself; for it is necessary that the sensible be present.
ὁμοίως δὲ τοῦτʼ ἔχει κἀν ταῖς ἐπιστήμαις ταῖς τῶν αἰσθητῶν, καὶ διὰ τὴν αὐτὴν αἰτίαν, ὅτι τὰ αἰσθητὰ τῶν καθʼ ἕκαστα καὶ τῶν ἔξωθεν.
And this is likewise also in the sciences of the sensibles, and for the same cause, because the sensibles are of particulars and from without.
ἀλλὰ περὶ μὲν τούτων διασαφῆσαι καιρὸς γένοιτʼ ἂν καὶ εἰσαῦθις· νῦν δὲ διωρίσθω τοσοῦτον, ὅτι οὐχ ἁπλοῦ ὄντος τοῦ δυνάμει λεγομένου, ἀλλὰ τοῦ μὲν ὥσπερ ἂν εἴποιμεν τὸν παῖδα δύνασθαι στρατηγεῖν, τοῦ δὲ ὡς τὸν ἐν ἡλικίᾳ ὄντα, οὕτως ἔχει τὸ αἰσθητικόν.
But of these things there may be an opportunity to make clear also hereafter; but for now let so much be defined, that since that which is spoken of as potential is not simple, but the one is as we would say that a child is capable of being a general, and the other as he who is of age, so is the sensitive.
ἐπεὶ δʼ ἀνώνυμος αὐτῶν ἡ διαφορά, διώρισται δὲ περὶ αὐτῶν ὅτι ἕτερα καὶ πῶς ἕτερα, χρῆσθαι ἀναγκαῖον τῷ πάσχειν καὶ ἀλλοιοῦσθαι ὡς κυρίοις ὀνόμασιν.
And since the difference between them has no name, but it has been defined concerning them that they are different and how they are different, it is necessary to use "undergoing" and "being altered" as proper names.
τὸ δʼ αἰσθητικὸν δυνάμει ἐστὶν οἷον τὸ αἰσθητὸν ἤδη ἐντελεχείᾳ, καθάπερ εἴρηται. πάσχει μὲν οὖν οὐχ ὅμοιον ὄν, πεπονθὸς δʼ ὡμοίωται καὶ ἔστιν οἷον ἐκεῖνο.
And the sensitive is potentially such as the sensible is already in actuality, as has been said; for it undergoes indeed not being like, but having undergone, it has been made like and is such as that.