§6.4Τὸ δὲ μεταβάλλον ἅπαν ἀνάγκη διαιρετὸν εἶναι.
It is necessary that everything that changes is divisible.
ἐπεὶ γὰρ ἔκ τινος εἴς τι πᾶσα μεταβολή, καὶ ὅταν μὲν ᾖ ἐν τούτῳ εἰς ὃ μετέβαλλεν, οὐκέτι μεταβάλλει, ὅταν δὲ ἐξ οὗ μετέβαλλεν, καὶ αὐτὸ καὶ τὰ μέρη πάντα, οὔπω μεταβάλλει (τὸ γὰρ ὡσαύτως ἔχον καὶ αὐτὸ καὶ τὰ μέρη οὐ μεταβάλλει), ἀνάγκη οὖν τὸ μέν τι ἐν τούτῳ εἶναι, τὸ δʼ ἐν θατέρῳ τοῦ μεταβάλλοντος·
For since every change is from something to something, and when a thing is in that into which it was changing, it is no longer changing, but when it, both itself and all its parts, is in that from which it was changing, it is not yet changing (for that which is in the same state, both itself and its parts, is not changing), it is necessary, therefore, that one part of that which is changing should be in the one, and another part in the other; for it is possible neither to be in both nor in neither.
οὔτε γὰρ ἐν ἀμφοτέροις οὔτʼ ἐν μηδετέρῳ δυνατόν. λέγω δʼ εἰς ὃ μεταβάλλει τὸ πρῶτον κατὰ τὴν μεταβολήν, οἷον ἐκ τοῦ λευκοῦ τὸ φαιόν, οὐ τὸ μέλαν·
I mean by 'that into which it changes' the first thing in the course of the change, as for instance the grey from the white, not the black; for it is not necessary that the changing thing should be in either of the extremes.
οὐ γὰρ ἀνάγκη τὸ μεταβάλλον ἐν ὁποτερῳοῦν εἶναι τῶν ἄκρων. φανερὸν οὖν ὅτι πᾶν τὸ μεταβάλλον ἔσται διαιρετόν.
It is manifest, therefore, that everything that changes will be divisible.
κίνησις δʼ ἐστὶν διαιρετὴ διχῶς, ἔνα μὲν τρόπον τῷ χρόνῳ, ἄλλον δὲ κατὰ τὰς τῶν μερῶν τοῦ κινουμένου κινήσεις, οἷον εἰ τὸ ΑΓ κινεῖται ὅλον, καὶ τὸ ΑΒ κινήσεται καὶ τὸ ΒΓ. ἔστω δὴ τοῦ μὲν ΑΒ ἡ ΔΕ, τοῦ δὲ ΒΓ ἡ ΕΖ κίνησις τῶν μερῶν.
Motion is divisible in two ways: in one way by time, and in another according to the motions of the parts of that which is in motion, as for instance, if the whole AC is in motion, both AB and BC will be in motion. Let the motion of the part AB be DE, and that of BC be EZ.
ἀνάγκη δὴ τὴν ὅλην, ἐφʼ ἧς ΔΖ, τοῦ ΑΓ εἶναι κίνησιν.
It is necessary indeed that the whole motion, represented by DZ, should be the motion of AC.
κινήσεται γὰρ κατὰ ταύτην, ἐπείπερ ἑκάτερον τῶν μερῶν κινεῖται καθʼ ἑκατέραν· οὐθὲν δὲ κινεῖται κατὰ τὴν ἄλλου κίνησιν· ὥστε ἡ ὅλη κίνησις τοῦ ὅλου ἐστὶν μεγέθους κίνησις.
For it will move according to this, since each of the parts moves according to each motion; and nothing moves according to the motion of another; so that the whole motion is the motion of the whole magnitude.
ἔτι δʼ εἰ πᾶσα μὲν κίνησις τινός, ἡ δʼ ὅλη κίνησις ἡ ἐφʼ ἧς ΔΖ μήτε τῶν μερῶν ἐστιν μηδετέρου (μέρους γὰρ ἑκατέρα) μήτʼ ἄλλου μηδενός (οὗ γὰρ ὅλη ὅλου, καὶ τὰ μέρη τῶν μερῶν· τὰ δὲ μέρη τῶν ΑΒ ΒΓ καὶ οὐδένων ἄλλων· πλειόνων γὰρ οὐκ ἦν μία κίνησις), κἂν ἡ ὅλη κίνησις εἴη τοῦ ΑΒΓ μεγέθους.
Furthermore, if every motion is the motion of something, and the whole motion represented by DZ is neither the motion of either of the parts (for each of these is the motion of a part) nor of any other thing (for where a whole motion is of a whole, the parts of the motion are of the parts of the magnitude, and the parts of the magnitude are AB and BC, and no others; for there was no single motion of more than one thing), then the whole motion would be the motion of the magnitude ABC.
ἔτι δʼ εἰ ἔστιν ἄλλη τοῦ ὅλου κίνησις, οἷον ἐφʼ ἧς ΘΙ, ἀφαιρεθήσεται ἀπʼ αὐτῆς ἡ ἑκατέρων τῶν μερῶν κίνησις· αὗται δʼ ἴσαι ἔσονται ταῖς ΔΕ ΕΖ· μία γὰρ ἑνὸς κίνησις.
Furthermore, if there is another motion of the whole, as for instance that represented by ΘI, there will be subtracted from it the motion of each of the parts; and these will be equal to DE and EZ; for there is one motion of one thing.
ὥστʼ εἰ μὲν ὅλη διαιρεθήσεται ἡ ΘΙ εἰς τὰς τῶν μερῶν κινήσεις, ἴση ἔσται ἡ ΘΙ τῇ ΔΖ· εἰ δʼ ἀπολείπει τι, οἷον τὸ ΚΙ, αὕτη οὐδενὸς ἔσται κίνησις (οὔτε γὰρ τοῦ ὅλου οὔτε τῶν μερῶν διὰ τὸ μίαν εἶναι ἑνός, οὔτε ἄλλου οὐθενός· ἡ γὰρ συνεχὴς κίνησίς ἐστι συνεχῶν τινῶν), ὡσαύτως δὲ καὶ εἰ ὑπερβάλλει κατὰ τὴν διαίρεσιν· ὥστʼ εἰ τοῦτο ἀδύνατον, ἀνάγκη τὴν αὐτὴν εἶναι καὶ ἴσην.
So that if the whole ΘI is divided into the motions of the parts, ΘI will be equal to ΔZ; but if there is any remainder, such as KI, this will be the motion of nothing (for it can be the motion neither of the whole nor of the parts, because there is one motion of one thing, nor of anything else; for continuous motion is of continuous things); and likewise if it exceeds in the division; so that if this is impossible, it is necessary that it be the same and equal.
αὕτη μὲν οὖν ἡ διαίρεσις κατὰ τὰς τῶν μερῶν κινήσεις ἐστίν, καὶ ἀνάγκη παντὸς εἶναι τοῦ μεριστοῦ αὐτήν·
This division, then, is according to the motions of the parts, and it is necessary that it belongs to everything that is divisible.
ἄλλη δὲ κατὰ τὸν χρόνον· ἐπεὶ γὰρ ἅποσα κίνησις ἐν χρόνῳ, χρόνος δὲ πᾶς διαιρετός, ἐν δὲ τῶ ἐλάττονι ἐλάττων ἡ κίνησις, ἀνάγκη πᾶσαν κίνησιν διαιρεῖσθαι κατὰ τὸν χρόνον.
But there is another division according to time; for since all motion is in time, and all time is divisible, and in less time the motion is less, it is necessary that all motion is divided according to time.
ἐπεὶ δὲ πᾶν τὸ
κινούμενον ἔν τινι κινεῖται καὶ χρόνον τινά, καὶ παντὸς ἔστι κίνησις, ἀνάγκη τὰς αὐτὰς εἶναι διαιρέσεις τοῦ τε χρόνου καὶ τῆς κινήσεως καὶ τοῦ κινεῖσθαι καὶ τοῦ κινουμένου καὶ ἐν ᾧ ἡ κίνησις (πλὴν οὐ πάντων ὁμοίως ἐν οἷς ἡ κίνησις, ἀλλὰ τοῦ μὲν τόπου καθʼ αὑτό, τοῦ δὲ ποιοῦ κατὰ συμβεβηκός).
And since everything in motion moves in something and for some time, and there is motion of everything, it is necessary that the same divisions belong to time and to motion, to the being in motion, to the thing in motion, and to that in which the motion is (except that that in which the motion is is not in all cases similarly divided, but place is divided in itself, while quality is divided accidentally).
εἰλήφθω γὰρ ὁ χρόνος ἐν ᾧ κινεῖται ἐφʼ ᾧ Α, καὶ ἡ κίνησις ἐφʼ ᾧ B. εἰ οὖν τὴν ὅλην ἐν τῷ παντὶ χρόνῳ κεκίνηται, ἐν τῷ ἡμίσει ἐλάττω, καὶ πάλιν τούτου διαιρεθέντος ἐλάττω ταύτης, καὶ ἀεὶ οὕτως.
For let the time in which it moves be represented by A, and the motion by B. If, then, it has moved through the whole motion in the whole time, in half the time it will have moved through less, and again when this is divided, through less than this, and always so.
ὁμοίως δὲ καί, εἰ ἡ κίνησις διαιρετή, καὶ ὁ χρόνος διαιρετός· εἰ γὰρ τὴν ὅλην ἐν τῷ παντί, τὴν ἡμίσειαν ἐν τῷ ἡμίσει, καὶ πάλιν τὴν ἐλάττω ἐν τῷ ἐλάττονι.
And likewise, if the motion is divisible, the time is also divisible; for if the whole motion is in the whole time, the half will be in the half, and again the less in the less.
τὸν αὐτὸν δὲ τρόπον καὶ τὸ κινεῖσθαι διαιρεθήσεται.
In the same way also, the being in motion will be divided.
ἔστω γὰρ ἐφʼ ὧ Γ τὸ κινεῖσθαι.
For let the being in motion be represented by Γ.
κατὰ δὴ τὴν ἡμίσειαν κίνησιν ἔλαττον ἔσται τοῦ ὅλου, καὶ πάλιν κατὰ τὴν τῆς ἡμισείας ἡμίσειαν, καὶ αἰεὶ οὕτως.
According to the half motion indeed, it will be less than the whole, and again according to the half of the half, and always so.
ἔστι δὲ καὶ ἐκθέμενον τὸ καθʼ ἑκατέραν τῶν κινήσεων κινεῖσθαι, οἶον κατά τε τὴν ΔΓ καὶ τὴν ΓΕ, λέγειν ὅτι τὸ ὅλον ἔσται κατὰ τὴν ὅλην (εἰ γὰρ ἄλλο, πλείω ἔσται κινεῖσθαι κατὰ τὴν αὐτὴν κίνησιν), ὥσπερ ἐδεί. ξαμεν καὶ τὴν κίνησιν διαιρετὴν εἰς τὰς τῶν μερῶν κινήσεις οὖσαν· ληφθέντος γὰρ τοῦ κινεῖσθαι καθʼ ἑκατέραν συνεχὲς ἔσται τὸ ὅλον.
It is possible also, by setting out the being in motion corresponding to each of the motions, as for instance according to ΔΓ and ΓΕ, to say that the whole will correspond to the whole motion (for if it were another, there will be more than one being in motion corresponding to the same motion), just as we showed that the motion is divisible into the motions of the parts; for when the being in motion corresponding to each part is taken, the whole will be continuous.
ὡσαύτως δὲ δειχθήσεται καὶ τὸ μῆκος διαιρετόν, καὶ ὅλως πᾶν ἐν ᾧ ἐστιν ἡ μεταβολή (πλὴν ἔνια κατὰ συμβεβηκός, ὅτι τὸ μεταβάλλον ἐστὶν διαιρετόν)· ἑνὸς γὰρ διαιρουμένου πάντα διαιρεθήσεται.
In the same way, the length will also be shown to be divisible, and in general everything in which the change is (except that some things are divided accidentally, because that which changes is divisible); for if one is divided, all will be divided.
καὶ ἐπὶ τοῦ πεπερασμένα εἶναι ἢ ἄπειρα ὁμοίως ἕξει κατὰ πάντων.
And in respect of being finite or infinite, it will hold similarly of all.
ἠκολούθηκεν δὲ μάλιστα τὸ διαιρεῖσθαι πάντα καὶ ἄπειρα εἶναι ἀπὸ τοῦ μεταβάλλοντος· εὐθὺς γὰρ ἐνυπάρχει τῷ μεταβάλλοντι τὸ διαιρετὸν καὶ τὸ ἄπειρον.
But the divisibility of all things and their being infinite follows especially from the changing thing; for divisibility and infinity are immediately inherent in that which changes.
τὸ μὲν οὖν διαιρετὸν δέδεικται πρότερον, τὸ δʼ ἄπειρον ἐν τοῖς ἑπομένοις ἔσται δῆλον.
Divisibility indeed has been shown before, but infinity will be manifest in what follows.