posited, must necessarily come to be by composition; but if the mode of generation by composition fits every generation, it has been superfluously distinguished from the other modes of generation by its own difference. Further, if the substrates in the aforesaid generations are substances and in them is observed the twofold aspect of the substrate, that is, the underlying and the opposite, but matter is not a substance, how does the mode of generation of things coming to be from substances fit the mode of generation of things not coming to be from substance? Therefore, it is necessary either that matter is a substance, or that the things coming to be from matter come to be in another mode apart from the aforesaid modes of generation. But since in the treatise of the Physics the matter has been defined not to be a substance and the mode of generation of things coming from it has not been handed down, how is this treatise not superfluous, in which what is clear is a puzzle? Further, if, as it is necessary for nature and for art not to make random things from random things, but definite things from definite things, so it is necessary also for God to make definite things from definite things, who is it that set this limit for God? But that God set this limit for nature and for art is evident. But if God is not under the limit, but makes random things from random things, not being prevented by the necessity of the limit from doing what he wills, how has he not been freed also from the limit of making things from substrates by necessity? b. From the same Aristotle, from the same discourse. The substrate is one in number, but two in form. For man and gold and matter in general are numerable; for it is more of a 'this', and what comes to be does not come to be from it accidentally; but privation and contrariety are an accident. But the form is one, such as order, music, or any of the other things so predicated. Wherefore it must be said that in one way the principles are two, but in another way three; and in one way they are the contraries, as if one were to say the musical and the unmusical, or the hot and the cold, or the harmonious and the inharmonious, but in another way not; for it is impossible for contraries to be acted upon by each other. This is also resolved by the fact that the substrate is something else; for this is not a contrary. So the principles are in a sense not more than the contraries, but two so to speak in number, nor again are they altogether two, because their being is different, but three. If the substrate is one in number but two in form, from which one must underlie the one, how is the substrate not its own substrate? But if this is impossible, how is it not false that the substrate is two in form? Further, if something must always underlie things that come to be, and this is matter, how is matter not always generable? For it always underlies one of the contraries. For it underlies either privation or the form which is contrary to privation; and with the form it becomes formed, but with privation formless. How then is matter not a generable substance, always having its being generably? Further, if privation is nothing

θετον, κατὰ σύνθεσιν ἀνάγκη γίνεσθαι· ἀλλ' εἰ ὁ τρόπος τῆς κατὰ σύνθεσιν γενέσεως πάσῃ γενέσει ἁρμόττει, περιττῶς τῶν ἄλλων τῆς γενέσεως τρόπων διέσταλται τῇ οἰκείᾳ διαφορᾷ. Ἔτι εἰ τὰ ὑποκείμενα ταῖς ·ηθείσαις γενέσεσιν οὐσίαι εἰσὶ καὶ ἐν αὐταῖς θεωρεῖται τὸ διττὸν τοῦ ὑποκειμένου, τουτέστι τὸ ὑποκείμενον καὶ τὸ ἀντικείμενον, ἡ δὲ ὕλη οὐσία οὐκ ἔστι, πῶς ἁρμόττει ὁ τρόπος τῆς γενέσεως τῶν ἐξ οὐσιῶν γιγνομέ νων τῷ τρόπῳ τῆς γενέσεως τῶν μὴ ἐξ οὐσίας γιγνομένων; Ἀνάγκη ἄρα ἢ οὐσίαν εἶναι τὴν ὕλην, ἢ τρόπῳ ἑτέρῳ γίγνεσθαι τὰ ἐκ τῆς ὕλης γιγνόμενα παρὰ τοὺς ·ηθέντας τρόπους τῆς γε νέσεως. Ἀλλ' ἐπειδὴ τῇ πραγματείᾳ τῆς Φυσικῆς ἀκροάσεως ἡ ὕλη διώρισται μὴ εἶναι οὐσία καὶ ὁ τρόπος τῆς γενέσεως τῶν ἐξ αὐτῆς γιγνομένων οὐ παραδέδοται, πῶς οὐ περιττὴ αὕτη ἡ πραγματεία, ἐν ᾗ τὸ σαφὲς ἄπορον; Ἔτι εἰ, ὡς ἀνάγκη τῇ φύσει καὶ τῇ τέχνῃ τὸ μὴ ἐκ τοῦ τυχόντος ποιεῖν τὰ τυχόντα, ἀλλ' ἐκ τῶν ὡρισμένων τὰ ὡρισμένα, οὕτως ἀνάγκη καὶ τῷ θεῷ ἐκ τῶν ὡρισμένων ποιεῖν τὰ ὡρισμένα, τίς ἐστιν ὁ τῷ θεῷ τοῦτον τὸν ὅρον θέμενος; Ὅτι δὲ τῇ φύσει καὶ τῇ τέχνῃ ὁ θεὸς ἔθηκε τοῦτον τὸν ὅρον, φανερόν. Eἰ δὲ ὁ θεὸς ὑπὸ τὸν ὅρον οὐκ ἔστιν, ἀλλὰ ποιεῖ ἐκ τοῦ τυχόντος τὰ τυχόντα, τῇ τοῦ ὅρου ἀνάγκῃ μὴ κωλυόμενος τοῦ ποιεῖν ἃ βούλεται, πῶς οὐκ ἠλευθέρωται καὶ τοῦ ὅρου τοῦ ποιεῖν ἐκ τῶν ὑποκειμένων κατ' ἀνάγκην; β. Τοῦ αὐτοῦ Ἀριστοτέλους ἐκ τοῦ αὐτοῦ λόγου. Ἔστι δὲ τὸ ὑποκείμενον ἀριθμῷ μὲν ἕν, εἴδει δὲ δύο. Ὁ μὲν γὰρ ἄνθρωπος καὶ ὁ χρυσὸς καὶ ὅλως ἡ ὕλη ἀριθμητή· τόδε γάρ τι μᾶλλον, καὶ οὐ κατὰ συμβεβηκὸς ἐξ αὐτοῦ γίνεται τὸ γιγνόμενον· ἡ δὲ στέρησις καὶ ἡ ἐναντίωσις συμβεβηκός· ἓν δὲ τὸ εἶδος, οἷον ἡ τάξις, ἡ μουσικὴ ἢ τῶν ἄλλων τι τῶν οὕτω κατηγορουμένων. ∆ι' ὧν ἔστι μὲν ὡς δύο λεκτέον εἶναι τὰς ἀρχάς, ἔστι δὲ ὡς τρεῖς· καὶ ἔστι μὲν ὡς τὰ ἐναντία, οἷον εἴ τις λέγοι τὸ μουσικὸν καὶ τὸ ἄμουσον ἢ τὸ θερμὸν καὶ τὸ ψυχρὸν ἢ τὸ ἡρμοσμένον καὶ τὸ ἀνάρμοστον, ἔστι δὲ ὡς οὔ· ὑπ' ἀλλήλων γὰρ πάσχειν τὰ ἐναντία ἀδύνατον. Λύεται δὲ καὶ τοῦτο διὰ τὸ ἄλλο εἶναι τὸ ὑποκείμενον· τοῦτο γὰρ οὐκ ἐναντίον. Ὥστε οὔτε πλείους τῶν ἐναντίων αἱ ἀρχαὶ τρόπον τινά, ἀλλὰ δύο ὡς εἰπεῖν τῷ ἀριθμῷ, οὔτε αὖ παντελῶς δύο διὰ τὸ ἕτερον ὑπάρχειν τὸ εἶναι αὐτοῖς, ἀλλὰ τρεῖς. Eἰ ἔστι τὸ ὑποκείμενον ἀριθμῷ μὲν ἕν, εἴδει δὲ δύο, ἀφ' ὧν δεῖ ἓν τῷ ἑνὶ ὑποκεῖσθαι, πῶς οὐκ ἔστι τὸ ὑποκείμενον αὐτὸ ἑαυτῷ ὑποκείμενον; Eἰ δὲ τοῦτο ἀδύνατον, πῶς οὐκ ἔστι ψευδὲς τὸ εἴδει δύο εἶναι τὸ ὑποκείμενον; Ἔτι εἰ δεῖ ὑπο κεῖσθαί τι ἀεὶ τῶν γιγνομένων, ἔστι δὲ τοῦτο ἡ ὕλη, πῶς οὐκ ἔστιν ἡ ὕλη ἀεὶ γενητή; Ἀεὶ γὰρ τῷ ἑνὶ τῶν ἐναντίων ὑπόκειται. Ἢ γὰρ τῇ στερήσει ὑπόκειται ἢ τῷ εἴδει ἐναν τίῳ ὄντι τῇ στερήσει· καὶ τῷ εἴδει μὲν γίνεται ἔμμορφος, τῇ στερήσει δὲ ἄμορφος. Πῶς οὖν οὐκ ἔστιν οὐσία γενητὴ ἡ ὕλη, ἀεὶ τὸ εἶναι γενητῶς ἔχουσα; Ἔτι εἰ ἡ στέρησις οὐδέν