§10.2κατὰ δὲ τὴν οὐσίαν καὶ τὴν φύσιν ζητητέον ποτέρως ἔχει, καθάπερ ἐν τοῖς διαπορήμασιν ἐπήλθομεν τί τὸ ἕν ἐστι καὶ πῶς δεῖ περὶ αὐτοῦ λαβεῖν, πότερον ὡς οὐσίας τινὸς οὔσης αὐτοῦ τοῦ ἑνός, καθάπερ οἵ τε Πυθαγόρειοί φασι πρότερον καὶ Πλάτων ὕστερον, ἢ μᾶλλον ὑπόκειταί τις φύσις καὶ δεῖ γνωριμωτέρως λεχθῆναι καὶ μᾶλλον ὥσπερ οἱ περὶ φύσεως· ἐκείνων γὰρ ὁ μέν τις φιλίαν εἶναί φησι τὸ ἓν ὁ δʼ ἀέρα ὁ δὲ τὸ ἄπειρον.
But we must investigate, with regard to substance and nature, how it stands, just as in our discussion of difficulties we went through the question of what the "one" is and how we must understand it—whether the "one" itself is a certain substance, as first the Pythagoreans say and later Plato, or rather some nature underlies it and it should be expressed in a more knowable way, rather like the physicists; for of these, one says the "one" is friendship, another air, and another the infinite.
εἰ δὴ μηδὲν τῶν καθόλου δυνατὸν οὐσίαν εἶναι, καθάπερ ἐν τοῖς περὶ οὐσίας καὶ περὶ τοῦ ὄντος εἴρηται λόγοις, οὐδʼ αὐτὸ τοῦτο οὐσίαν ὡς ἕν τι παρὰ τὰ πολλὰ δυνατὸν εἶναι (κοινὸν γάρ) ἀλλʼ ἢ κατηγόρημα μόνον, δῆλον ὡς οὐδὲ τὸ ἕν· τὸ γὰρ ὂν καὶ τὸ ἓν καθόλου κατηγορεῖται μάλιστα πάντων.
If, then, no universal can be a substance, as has been said in our discussions on substance and being, neither can this itself be a substance as a "one" apart from the many (for it is common) but rather only a predicate, and so it is clear that the "one" cannot be a substance either; for "being" and the "one" are predicated universally most of all.
ὥστε οὔτε τὰ γένη φύσεις τινὲς καὶ οὐσίαι χωρισταὶ τῶν ἄλλων εἰσίν, οὔτε τὸ ἓν γένος ἐνδέχεται εἶναι διὰ τὰς αὐτὰς αἰτίας διʼ ἅσπερ οὐδὲ τὸ ὂν οὐδὲ τὴν οὐσίαν.
Therefore, neither are genera certain natures and substances separate from other things, nor can the "one" be a genus, for the same reasons that neither "being" nor "substance" can be.
ἔτι δʼ ὁμοίως ἐπὶ πάντων ἀναγκαῖον ἔχειν·
Furthermore, it must be the same in all cases.
λέγεται δʼ ἰσαχῶς τὸ ὂν καὶ τὸ ἕν·
And "being" and "one" are spoken of in an equal number of ways.
ὥστʼ ἐπείπερ ἐν τοῖς ποιοῖς ἐστί τι τὸ ἓν καί τις φύσις, ὁμοίως δὲ καὶ ἐν τοῖς ποσοῖς, δῆλον ὅτι καὶ ὅλως ζητητέον τί τὸ ἕν, ὥσπερ καὶ τί τὸ ὄν, ὡς οὐχ ἱκανὸν ὅτι τοῦτο αὐτὸ ἡ φύσις αὐτοῦ.
Therefore, since in the case of qualities the "one" is some thing and some nature, and similarly in the case of quantities, it is clear that we must also investigate in general what the "one" is, just as we must investigate what "being" is, since it is not enough to say that this itself is its nature.
ἀλλὰ μὴν ἔν γε χρώμασίν ἐστι τὸ ἓν χρῶμα, οἷον τὸ λευκόν, εἶτα τὰ ἄλλα ἐκ τούτου καὶ τοῦ μέλανος φαίνεται γιγνόμενα, τὸ δὲ μέλαν στέρησις λευκοῦ ὥσπερ καὶ φωτὸς σκότος·
But indeed, in colors at least, the "one" is a single color, for instance white, and then the others appear to come from this and black, black being the privation of white, just as darkness is of light.
ὥστε εἰ τὰ ὄντα ἦν χρώματα, ἦν ἂν ἀριθμός τις τὰ ὄντα, ἀλλὰ τίνων;
Thus if beings were colors, beings would be some number, but of what?
δῆλον δὴ ὅτι χρωμάτων, καὶ τὸ ἓν ἦν ἄν τι ἕν, οἷον τὸ λευκόν.
Clearly of colors, and the "one" would be some one thing, for instance white.
ὁμοίως δὲ καὶ εἰ μέλη τὰ ὄντα ἦν, ἀριθμὸς ἂν ἦν, διέσεων μέντοι, ἀλλʼ οὐκ ἀριθμὸς ἡ οὐσία αὐτῶν· καὶ τὸ ἓν ἦν ἄν τι οὗ ἡ οὐσία οὐ τὸ ἓν ἀλλὰ δίεσις.
Similarly, also if beings were melodies, they would be a number, of quarter-tones indeed, but their substance would not be number; and the "one" would be some one thing whose substance was not the "one" but a quarter-tone.
ὁμοίως δὲ καὶ ἐπὶ τῶν φθόγγων στοιχείων ἂν ἦν τὰ ὄντα ἀριθμός, καὶ τὸ ἓν στοιχεῖον φωνῆεν.
Similarly, also in the case of speech, beings would be a number of elements, and the "one" would be a vocalic element.
καὶ εἰ σχήματα εὐθύγραμμα, σχημάτων ἂν ἦν ἀριθμός, καὶ τὸ ἓν τὸ τρίγωνον.
And if they were rectilinear figures, they would be a number of figures, and the "one" would be the triangle.
ὁ δʼ αὐτὸς λόγος καὶ ἐπὶ τῶν ἄλλων γενῶν, ὥστʼ εἴπερ καὶ ἐν τοῖς πάθεσι καὶ ἐν τοῖς ποιοῖς καὶ ἐν τοῖς ποσοῖς καὶ ἐν κινήσει ἀριθμῶν ὄντων καὶ ἑνός τινος ἐν ἅπασιν ὅ τε ἀριθμὸς τινῶν καὶ τὸ ἓν τὶ ἕν, ἀλλʼ οὐχὶ τοῦτο αὐτὸ ἡ οὐσία, καὶ ἐπὶ τῶν οὐσιῶν ἀνάγκη ὡσαύτως ἔχειν· ὁμοίως γὰρ ἔχει ἐπὶ πάντων.
And the same argument holds also for other genera; so that if indeed, both in affections and in qualities and in quantities and in motion, there are numbers and some "one" in all of them, and while the number is of certain things and the "one" is some particular "one", but this itself is not their substance, then it must be the same also in the case of substances; for it is the same in all cases.
—ὅτι μὲν οὖν τὸ ἓν ἐν ἅπαντι γένει ἐστί τις φύσις, καὶ οὐδενὸς τοῦτό γʼ αὐτὸ ἡ φύσις τὸ ἕν, φανερόν, ἀλλʼ ὥσπερ ἐν χρώμασι χρῶμα ἓν ζητητέον αὐτὸ τὸ ἕν, οὕτω καὶ ἐν οὐσίᾳ οὐσίαν μίαν αὐτὸ τὸ ἕν·
It is clear, then, that the "one" in every genus is some nature, and that the "one" itself is the nature of nothing; but just as in colors we must seek the "one" itself as one color, so in substance we must seek the "one" itself as one substance.
ὅτι δὲ ταὐτὸ σημαίνει πως τὸ ἓν καὶ τὸ ὄν, δῆλον τῷ τε παρακολουθεῖν ἰσαχῶς ταῖς κατηγορίαις καὶ μὴ εἶναι ἐν μηδεμιᾷ (οἷον οὔτʼ ἐν τῇ τί ἐστιν οὔτʼ ἐν τῇ ποῖον, ἀλλʼ ὁμοίως ἔχει ὥσπερ τὸ ὄν) καὶ τῷ μὴ προσκατηγορεῖσθαι ἕτερόν τι τὸ εἷς ἄνθρωπος τοῦ ἄνθρωπος (ὥσπερ οὐδὲ τὸ εἶναι παρὰ τὸ τί ἢ ποῖον ἢ πόσον) καὶ τῷ εἶναι τὸ ἑνὶ εἶναι τὸ ἑκάστῳ εἶναι.
And that the "one" and "being" signify in a way the same thing, is clear both from their accompanying the categories in an equal number of ways and from their not being in any of them (as, for instance, neither in "what it is" nor in "of what sort", but standing in the same relation as "being"), and from "one man" not being predicated as something other than "man" (just as "to be" is not something apart from "what" or "of what sort" or "how much"), and from "to be one" being "to be each thing".