§1.44.
4.
Περὶ δὲ γενέσεως καὶ ἀλλοιώσεως λέγωμεν τί διαφέρουσιν· φαμὲν γὰρ ἑτέρας εἶναι ταύτας τὰς μεταβολὰς ἀλλήλων.
Concerning generation and alteration, let us state how they differ; for we say that these changes are different from one another.
ἐπειδὴ οὖν ἐστί τι τὸ ὑποκείμενον καὶ ἕτερον τὸ πάθος ὅ κατὰ τοῦ ὑποκειμένου λέγεσθαι πέφυκεν, καὶ ἔστι μεταβολὴ ἑκατέρου τούτων, ἀλλοίωσις μέν ἐστιν, ὅταν ὑπομένοντος τοῦ ὑποκειμένου, αἰσθητοῦ ὄντος, μεταβάλλῃ ἐν τοῖς αὐτοῦ πάθεσιν, ἢ ἐναντίοις οὖσιν ἢ μεταξύ, οἷον τὸ σῶμα ὑγιαίνει καὶ πάλιν κάμνει ὑπομένον γε ταὐτό, καὶ ὁ χαλκὸς στρογγύλος, ὁτὲ δὲ γωνιοειδὴς ὁ αὐτός γε ὤν.
Since, then, there is some underlying subject, and other is the property which is by nature said of the underlying subject, and there is a change of each of these, it is alteration when, while the underlying subject persists (being sensible), it changes in its own properties, whether they are contraries or intermediate, for example, the body is healthy and again sick, persisting as the same indeed, and the bronze is round, and at another time angular, being indeed the same.
ὅταν δ᾿ ὅλον μεταβάλλῃ μὴ ὑπομένοντος αἰσθητοῦ τινὸς ὡς ὑποκειμένου τοῦ αὐτοῦ, ἀλλ᾿ οἶον ἐκ τῆς γονῆς αἷμα πάσης ἢ ἐξ ὕδατος ἀὴρ ἢ ἐξ ἀέρος παντὸς ὕδωρ, γένεσις ἥδη τὸ τοιοῦτον, τοῦ δὲ φθορά, μάλιστα δέ, ἂν ἡ μεταβολὴ γίνηται ἐξ ἀναισθήτου εἰς αἰσθητὸν ἢ ἀφῇ ἢ πάσαις ταῖς αἰσθήσεσιν, οἶον ὅταν ὕδωρ γένηται ἢ φθαρῇ εἰς ἀέρα· ὁ γὰρ ἀὴρ ἐπιεικῶς ἀναίσθητον.
But when the whole changes, without any sensible underlying subject persisting as the same, but for example, blood comes from the whole semen, or air from water, or water from the whole air, such a thing is already the generation of one and the destruction of the other, and especially if the change occurs from the imperceptible to the perceptible, either by touch or by all senses, for example, when water comes to be or is destroyed into air; for air is fairly imperceptible.
ἐν δὲ τούτοις ἄν τι ὑπομένῃ πάθος τὸ αὐτὸ ἐναντιώσεως ἐν τῷ γενομένῳ καὶ τῷ φθαρέντι (οἶον ὅταν ἐξ ἀέρος ὕδωρ, εἰ ἄμφω διαφανῆ ἢ ψυχρά), οὐ δεῖ τούτου θάτερον πάθος εἶναι εἰς ὃ μεταβάλλει.
But if, in these cases, some same property of a contrariety persists in what has come to be and what has been destroyed (for example, when water from air, if both are transparent or cold), that into which it changes must not be the other property of this [contrariety].
εἰ δὲ μή, ἔσται ἀλλοίωσις.
Otherwise it will be alteration.
οἷον ὁ μουσικὸς ἄνθρωπος ἐφθάρη, ἄνθρωπος δ᾿ ἄμουσος ἐγένετο, ὁ δ᾿ ἄνθρωπος ὑπομένει τὸ αὐτό.
For example, the musical man was destroyed, and an unmusical man came to be, but the man persists as the same.
εἰ μὲν οὖν τούτου μὴ πάθος ἦν καθ᾿ αὑτὸ ἡ μουσικὴ καὶ ἡ ἀμουσία, τοῦ μὲν γένεσις ἦν ἄν, τοῦ δὲ φθορά· διὸ ἀνθρώπου μὲν ταῦτα πάθη, ἀνθρώπου δὲ μουσικοῦ καὶ ἀνθρώπου ἀμούσου γένεσις καὶ φθορά·
If, therefore, music and unmusicality were not a property of this [man] in itself, there would have been a generation of the one and a destruction of the other; hence, while these are properties of man, they are the generation and destruction of "musical man" and "unmusical man".
νῦν δὲ πάθος τοῦτο τοῦ ὑπομένοντος.
But as it is, this is a property of the persisting subject.
διὸ ἀλλοίωσις τὰ τοιαῦτα.
Hence such things are alteration.
Ὅταν μὲν οὖν κατὰ τὸ ποσὸν ᾖ ἡ μεταβολὴ τῆς ἐναντιώσεως, αὔξη καὶ φθίσις, ὅταν δὲ κατὰ τόπον, φορά, ὅταν δὲ κατὰ πάθος καὶ τὸ ποιόν, ἀλλοίωσις.
Therefore, when the change of contrariety is according to quantity, it is growth and decay; and when according to place, locomotion; and when according to property and quality, alteration.
ὅταν δὲ μηδὲν ὑπομένῃ οὗ θάτερον πάθος ἢ συμβεβηκὸς ὅλως, γένεσις, τὸ δὲ φθορά.
But when nothing persists of which the other is a property or an accident at all, it is generation, and the other is destruction.
ἔστι δὲ ὕλη μάλιστα μὲν καὶ κυρίως τὸ ὑποκείμενον γενέσεως καὶ φθορᾶς δεκτικόν, τρόπον δέ τινα καὶ τὸ τοῖς ἄλλαις μεταβολαῖς, ὅτι πάντα δεκτικὰ τὰ ὑποκείμενα ἐναντιώσεών τινων.
And matter is, most of all and properly, the underlying subject receptive of generation and destruction, but in a way also that of other changes, because all underlying subjects are receptive of certain contrarieties.
περὶ μὲν οὖν γενέσεως,¹ εἴτε ἔστιν εἴτε μή, καὶ πῶς ἔστι, καὶ περὶ ἀλλοιώσεως διωρίσθω τοῦτον τὸν τρόπον.
Concerning generation, then, whether it is or is not, and how it is, and concerning alteration, let it be defined in this way.