ὦ In interpreting and expanding this difficult passage I follow Simplicius. The first κινουμένων refers to all material entities that are in motion. The second κινουμένων (as would be more easily seen if it had been preceded by ἀρχαί instead of ἀρχή) refers to the class of causes of motion described above as κινούμενον, aS opposed to ἀκίνητον.υ The active factor in such causes shares incidentally in the essential but.the (ultimate and) universal cause lies in a principle that does not move at all. That there really are beings that move themselves, to wit living things and (especially) animals, is plain to see, and accordingly they gave rise to the suggestion ὃ that it is possible for there to be such a thing as the absolute initiation of movement de novo, as seen in these creatures; for they seem to be without motion and then again to move. It is therefore important to note that this is only true at all of one order of their movements,° and not strictly true of that. For such motion in animals is not self-determined but due to other natural changes which occur in them not by their own agency: growth, decay, and breathing, for instance, go on naturally when they are at rest and not making the movements they themselves determine; and the causes of these latter movements are found in the environment or in things that enter into the organism itself. Thus animals’ food causes some of their motions, since they sleep while the food is being digested, and when it is being distributed they wake and move themselves, but on the initiation of an external cause. And this is why they do not maintain continuous and unceasing self-movements, since there is in every case another cause, of the order of movers that are themselves in motion, which changes when it acts upon the self-moving movement which it provokes in the passive factor; so that the concrete being is self-moved. But seeing that this active factor will be shown (in the immediate sequel) to be itself a link in a chain and not a true initiator of movement, it follows that the ultimate cause of all motion is itself exempt from any share (even incidental) in the motion it causes.
> [This suggestion was provisionally rejected in chap. ii. 253 a 7 ff.—C. | ¢ [Namely, id movements.—C.]
29b πρὸς ἕκαστον τῶν κινούντων ἑαυτά. ἐν πᾶσι δὲ τούτοις κινεῖται τὸ κινοῦν πρῶτον καὶ τὸ αἴτιον τοῦ αὐτὸ ἑαυτὸ κινεῖν ὑφ᾽ αὑτοῦ" κατὰ συμβε- βηκὸς μέντοι, μεταβάλλει γὰρ τὸν τόπον τὸ σῶμα, Ὁ ὥστε καὶ τὸ ἐν τῷ σώματι ὃν καὶ τῇ “μοχλείᾳ' κινοῦν ἑαυτό. ἐξ ὧν ἔστι πιστεῦσαι ὅτι εἴ τί ἐστι τῶν ἀκινήτων μὲν κινούντων δὲ καὶ αὐτῶν κινουμένων κατὰ συμβεβηκός, ἀδύνατον συνεχῆ κίνησιν κινεῖν. ὥστ᾽ εἴπερ ἀνάγκη συνεχῶς εἶναι κίνησιν, εἶναί τι δεῖ τὸ πρῶτον κινοῦν ἀκίνητον 25 καὶ κατὰ συμβεβηκός, εἰ μέλλει (καθάπερ εἴ- πομενὶ) ἔσεσθαι ἐν τοῖς οὖσιν ἄπαυστός τις καὶ ἀθάνατος κίνησις καὶ μενεῖν" τὸ ὃν αὐτὸ ἐν αὑτῷ καὶ ἐν τῷ αὐτῷ" τῆς γὰρ ἀρχῆς μενούσης ἀνάγκη καὶ τὸ πᾶν μένειν, συνεχὲς ὃν πρὸς τὴν ἀρχήν. (οὐκ é ἔστι δὲ τὸ αὐτὸ τὸ κινεῖσθαι κατὰ cup εβηκὸς ὑφ᾽ αὑτοῦ καὶ ὑφ᾽ ἑτέρου" τὸ μὲν “γὰρ ὑφ᾽ ἑτέρου 80 ὑπάρχει καὶ τῶν ἐν τῷ οὐρανῷ ἐνίαις ἀρχαῖς, ὅσα πλείους φέρεται φοράς, θάτερον δὲ τοῖς φθαρτοῖς μόνον.) ᾿Αλλὰ μὴν εἴ γε ἔστι τι ἀεὶ τοιοῦτον, κινοῦν μέν τι ἀκίνητον δὲ αὐτὸ καὶ ἀΐδιον, ἀνάγκη καὶ τὸ 260a πρῶτον ὑπὸ τούτου κινούμενον ἀΐδιον εἶναι. ἔστι δὲ τοῦτο δῆλον μὲν καὶ ἐκ τοῦ μὴ ἂν ἄλλως εἶναι γένεσιν καὶ φθορὰν καὶ μεταβολὴν τοῖς 1 [τῇ μοχλείᾳ HIK, Simplic. 1256. 32 (lemma): τὸ ἐν τῇ μοχλείᾳ al.—C.]
2 [καὶ H, Simplic. 1260. 11: καὶ μὴ cett.—C.] 3 [μενεῖν Oxf. Trans. coll. Them. 224.21: μένειν codd.—C.]
α [Namely, the soul. If this changes its place, it does so only as contained in a body which moves about carrying the soul with it, and which the soul uses as a sort of lever.—C.]
organism. And in all these cases the active factor of movement,” the source of movement which is the cause of the whole organism being self-moving, is itself also set in motion by itself, but only incidentally; for the body changes its place, and is accompanied in this change by that within the body which moves itself too with leverage it employs. Whence we may infer that no member of the class of the (essentially) unmoved causes of movement which is itself moved incidentally can be the cause of continuous movement. So that if there must needs be a continuous movement, there must be some primary mover which is not even incidentally moved, if, as we have said,® there is to be amongst things that exist a certain unceasing and deathless movement, and the universe is to abide self-contained and constant; for only if the principle abides, the sum of things, being in continuous relation with it, must also abide. (But it is not the same for an agent to be incidentally moved by itself or by some other, for to be so moved by another applies to some principles of heavenly bodies, those to wit which are carried by several motions. But the other alternative—that it should be incidentally self-moved—occurs only in perishable things.)
But if there really is such an existence (A), causing motion but itself unmoved and eternal, that (B) which is immediately moved by it must likewise be eternal. This is evident from the very fact that genesis and evanishment and change occur to all else for no other reason than that they are moved by something that δ (Chap. i.—C.] ¢ For the movements of the heavenly bodies see Vol. I. Introd. Ὁ. Ixviii and Introd. Note to this chapter.
260 a ἄλλοις, εἰ μή τι κινήσει κινούμενον" τὸ μὲν γὰρ ἀκίνητον ἀεὶ τὸν αὐτὸν κινήσει τρόπον καὶ μίαν δ κίνησιν, ἅτε οὐδὲν αὐτὸ μεταβάλλον πρὸς τὸ κινούμενον: τὸ δὲ κινούμενον ὑπὸ τοῦ κινουμένου μέν, ὑπὸ τοῦ ἀκινήτου δὲ κινουμένου ἤδη, διὰ τὸ ἄλλως καὶ ἄλλως ἔχειν πρὸς τὰ πράγματα, οὐ τῆς αὐτῆς ἔσται κινήσεως αἴτιον, ἀλλὰ.dia τὸ ἐν ἐναντίοις εἶναι τόποις ἢ εἴδεσιν ἐναντίως παρ- 10 ἔξεται κινούμενον ἕκαστον τῶν ἄλλων, καὶ ὁτὲ μὲν ἠρεμοῦν, ὁτὲ δὲ κινούμενον. ανερὸν δὴ γέγονεν ἐκ τῶν εἰρημένων καὶ ὃ κατ᾽ ἀρχὰς ἠποροῦμεν, τί δή ποτε οὐ πάντα ἣ κινεῖται ἢ ἠρεμεῖ, 7 ἢ τὰ μὲν κινεῖται ἀεὶ τὰ δ᾽ ἀεὶ ἠρεμεῖ, ἀλλ᾽ ἔνια ὁτὲ “μὲν ὁτὲ δ᾽ οὔ. τούτου γὰρ τὸ αἴτιον 15 δῆλόν ἐστι νῦν, ὅτι τὰ μὲν ὑπὸ ἀκινήτου κινεῖται ἀιδίου, διὸ ἀεὶ κινεῖται, τὰ δ᾽ ὑπὸ κινουμένου καὶ μεταβάλλοντος, ὥστε καὶ αὐτὰ ἀναγκαῖον μετα- βάλλειν. τὸ δ᾽ ἀκίνητον, ὥσπερ εἴρηται, ἅτε ἁπλῶς καὶ ὡσαύτως καὶ ἐν τῷ αὐτῷ διαμένον, μίαν καὶ ἁπλῆν κινήσει κίνησιν.
[A fresh start. Can any motion continue for ever without interruption, and if so what motion? And what form of motion rs prior to all others? If motion is to be eternal, the motion which is both continuous and primary must be that caused by the primary mover (260 a 20-26).
Local motion is prior both to change of quality and to change of quantity: such changes cannot occur without movement in space (a 26-b 15).
PHYSICS, VIII. vz.-vi.
is itself in motion; for the motion caused by the unmoved (A) will be a single motion caused always in the same way, since it in no way changes in relation to the mobile; whereas that (C) which is moved by an agent (B) that is in motion, though that motion be immediately caused by the unmoving, inasmuch as it (C) changes its relation to the things (D) it moves, will not cause a uniform movement, but because of its contrasted positions or characteristics will produce contrary movements in each of the things it affects, and any such movements will be intermittent.
So now, from all that has been said, the answer is clear to the question from which we started: How comes it about that it is neither true that all things are in motion nor that all things are at rest, nor that some things are always in motion and the remainder always at rest, but that there are things which are sometimes in the one state and sometimes in the other? The reason of this is now obvious, namely, that some things derive their motion from an eternal and immovable cause, and therefore their motion is constant, whereas others derive their motion from a cause which is itself in motion and changing, and therefore they also must necessarily be changing. The immovable, as we have said, being simple and unchanging and self-constant, causes an unbroken and simple motion.
ARGUMENT (continued) Local motion is prior to all other kinds of change in all the three senses of priority (Ὁ 15-19): (1) it can exist without the others, but the others cannot exist without it (b 19-29); ARGUMENT (continued) (2) it is prior in time, as the only motion possible to eternal things; and locomotion must precede even ἡ coming-intobeing’ (Ὁ 29-261 a 12); (8) it is prior in the order of nature, as being last in the order of development of the perfect form Locomotion, then, being prior to all other changes, what species of locomotion is primary? The answer will establish what we have assumed—that a continuous eternal motion is possible (a 27-31).
No other kind of change can continue without interruption, 260 a 20 Οὐ μὴν ἀλλὰ καὶ ἄλλην ποιησαμένοις ἀρχὴν μᾶλ- λον ἔσται περὶ τούτων φανερόν. σκεπτέον “γὰρ πό- τερον ἐνδέχεταί τινα κίνησιν εἶναι συνεχῆ ἢ οὔ, καὶ εἰ ἐνδέχεται, τίς αὕτη, καὶ τίς πρώτη τῶν κινήσεων" δῆλον γὰρ ὡς εἴπερ ἀναγκαῖον μὲν ἀεὶ κίνησιν εἶναι, 96 πρώτη δὲ ἧδε καὶ συνεχής, ὅτι τὸ πρῶτον κινοῦν κινεῖ ταύτην τὴν κίνησιν, ἣν ἀναγκαῖον μίαν καὶ τὴν αὐτὴν εἶναι καὶ συνεχῆ καὶ ᾿ πρώτην.
Τριῶν δ᾽ οὐσῶν κινήσεων, τῆς τε κατὰ μέγεθος καὶ τῆς κατὰ πάθος καὶ τῆς κατὰ τόπον, ἣν καλοῦ- μεν φοράν, ταύτην ἀναγκαῖον εἶναι πρώτην. ἀδύνα- 80 TOV γὰρ αὔξησιν εἶναι ἀλλοιώσεως μὴ προυπαρ- χούσης" τὸ “γὰρ αὐξανόμενον ἔστι μὲν ὡς ὁμοίῳ av ἄνεται, ἔστι δ᾽ ὡς ἀνομοίῳ" τροφὴ γὰρ λέγεται τῷ ἐναντίῳ τὸ ἐναντίον, προσγίγνεται é πᾶν γιγνόμενον ὅμοιον ὁμοίῳ. ἀνάγκη οὖν ἀλλοίω- 260 b ow εἶναι τὴν εἰς τἀναντία μεταβολήν. ἀλλὰ μὴν εἴ γε ἀλλοιοῦται, δεῖ τι εἶναι τὸ ἀλλοιοῦν καὶ ποιοῦν ἐκ τοῦ δυνάμει θερμοῦ τὸ ἐνεργείᾳ θερμόν.
¢ [This doctrine that nourishment involves qualitative assimilation is discussed in De anima 416 a 19 ff.—C.
ARGUMENT (continued) because all other kinds of change take place in opposite directions between contrary, or (in the case of genesis and perishing) contradictory, extremes. When the change reaches an extreme it must cease. Whether it is succeeded by a state of rest or by a contrary change does not matter; what matters is that no change can coexist with either rest or the contrary change (a 31—b 26).—C.]
But conclusive as all this may be, it will be clearer yet if we start again and approach it from another direction. For we may ask ourselves whether it is possible for there to be any continuous motion at all, and if so of what nature such motion must be; and also what kind of motion must be prior to all others. For it is obvious that if there must be eternal motion, and if some particular motion is primary and continuous, then that is just the motion which the prime mover causes—necessarily unbroken and uniform and everlasting and primary.
Now of the three kinds of motion (in the larger sense of change in general), to wit change of quantity, change of quality, and change of place, which we call ‘ locomotion,’ this last named must come first. For growth cannot take place without change of qualities preceding it, for though that which grows may be said in one sense to increase by addition of its like, in another sense it grows by addition of its unlike; for there is a contrast of unlikeness between the food and the fed, and every accession is caused by the unlike becoming like, which passage from unlikeness to likeness constitutes change of quality.* But if there is change of quality there must be something that causes the change and makes, for instance, what was susceptible of being heated 260b δῆλον οὖν ὅτι TO κινοῦν οὐχ ὁμοίως ἔχει, ἀλλ᾽ ὁτὲ μὲν ἐγγύτερον OTe δὲ πορρώτερον τοῦ ἀλλοιουμένου ὅ ἐστίν: ταῦτα δ᾽ ἄνευ φορᾶς οὐκ ἐνδέχεται ὑπάρχειν. εἰ ἄρα ἀνάγκη ἀεὶ κίνησιν εἶναι, ἀνάγκη καὶ φορὰν ἀεὶ εἶναι πρώτην τῶν κινήσεων, καὶ φορᾶς, εἰ ἔστιν ἡ μὲν πρώτη ἡ δ᾽ ὑστέρα, τὴν πρώτην. ἔτι δὲ πάντων τῶν παθημάτων ἀρχὴ πύκνωσις καὶ μάνωσις---καὶ yap βαρὺ καὶ κοῦφον καὶ μαλακὸν 10 Kal σκληρὸν καὶ θερμὸν καὶ ψυχρὸν πυκνότητες δοκοῦσι καὶ ἀραιότητες εἶναί τινες--πύκνωσις δὲ καὶ μάνωσις σύγκρισις καὶ διάκρισις, καθ᾽ ἃς γένεσις καὶ φθορὰ λέγεται τῶν οὐσιῶν" συγκρινό- μενα δὲ καὶ διακρινόμενα ἀνάγκη κατὰ τόπον μεταβάλλειν. ἀλλὰ μὴν καὶ τοῦ αὐξανομένου καὶ φθίνοντος μεταβάλλει κατὰ τόπον τὸ μέγεθος. is Ἔστι καὶ ἐντεῦθεν ἐπισκοποῦσιν ἔσται φανερὸν ὅτι ἡ φορὰ πρώτη. τὸ γὰρ πρῶτον ὥσπερ καὶ ἐπὶ τῶν ἄλλων, οὕτω καὶ ἐπὶ κινήσεως ἂν λέγοιτο πλεοναχῶς" λέγεται δὲ πρότερον, οὗ τε μὴ ὄντος οὐκ ἔσται τἄλλα, ἐκεῖνο δὲ ἄνευ τῶν ἄλλων, καὶ τὸ τῷ χρόνῳ, καὶ τὸ κατ᾽ οὐσίαν.
α Philoponus, Albertus Magnus, and Aquinas all insist that Aristotle is here taking the Atomists on their own ground but not committing himself to their doctrine. Hence the reservations ‘ are taken to be’ and ‘ are supposed to be.’ [The reference may be to the Ionian Monists. At Met. 988 b 29 ff. they are criticized, as a group, for deriving the qualitative differences of the four elements from the σύγκρισις (i.e. πύκνωσις) of a single primary element without deciding whether this is to be Fire or Air or Water. See Simplic. Phys. 1319. 17 ff. Cf. 265 Ὁ 17-266 a 5, where Aristotle says that all the physicists down to and including Plato actually hot. And for this to come about the moving cause obviously cannot remain just as it was, but must approach or recede from that which it modifies; and that can only happen by local movement. If, then, there must always be motion (in the larger sense) there must always be local movement, which takes precedence amongst all the kinds of motion; and if there is an order of precedence in the different kinds of local movements, then it must be the primal form of local movement that always continues. Further, the principle of all changes of quality is condensation and rarification, for heavy and light, soft and hard, hot and cold are taken to be different manifestations of condensation and rarification, and condensation and rarification, again, to be identical with the combination and resolution by which the genesis and evanishment of things are supposed to come about. But combination and resolution necessarily involve change of place. Moreover, all that grows or shrinks changes locally in that it changes in size.® Yet again it can be proved that local motion takes precedence of the others by the following considerations. In regard to motion, as in regard to everything else, ‘priority’ has several meanings: (1) that has priority without which the things to which it is said to be prior cannot exist, whereas it can exist without them; (2) the priority may be in time; and (3) in respect of perfection of nature.
implied that locomotion was the primary form of all change.—C, | ὃ It has been shown that its nourishment changes in quality and that this involves local changes. It is now added that the mere occupying more or less room is itself a local change.
260b20 Ὥστ᾽ ἐπεὶ κίνησιν μὲν ἀναγκαῖον εἶναι συνεχῶς, εἴη δ᾽ ἂν συνεχῶς ἢ ἡ συνεχὴς ἢ ἡ ἐφεξῆς, μᾶλλον ἡ συνεχής, καὶ βέλτιον συνεχῆ ἢ ἐφεξῆς εἶναι, τὸ δὲ βέλτιον ἀεὶ ὑπολαμβάνομεν ἐν τῇ φύσει ὑπάρχειν, ἂν ἢ δυνατόν, δυνατὸν δὲ συνεχῆ εἶναι (δειχθήσεται δὲ ὕστερον: νῦν δὲ τοῦθ᾽ ὑποκείσθω), Kal ταύτην οὐδεμίαν ἄλλην οἷόν 7° εἶναι ἀλλ᾽ ἢ φοράν, ἀνάγκη τὴν φορὰν εἷναι πρώτην. οὐδεμία yap ἀνάγκη οὔτε αὔξεσθαι οὔτε ἀλλοιοῦσθαι τὸ φερόμενον, οὐδὲ δὴ γίγνεσθαι ἢ φθείρεσθαι": τούτων δὲ οὐδεμίαν ἐνδέχεται τῆς συνεχοῦς μὴ οὔσης, ἣν κινεῖ TO πρῶτον κινοῦν.
30 “Ere χρόνῳ πρώτην’ τοῖς yap ἀιδίοις μόνον ἐνδέχεται κινεῖσθαι ταύτην. ἀλλ᾽ ἐφ᾽ ἑνὸς μὲν ὁτουοῦν τῶν ἐχόντων γένεσιν τὴν φορὰν ἀναγ- καῖον ὑστάτην εἶναι τῶν κινήσεων: μετὰ γὰρ τὸ γενέσθαι πρῶτον ἀλλοίωσις καὶ αὔξησις, φορὰ 2618 δ᾽ ἤδη τετελειωμένων κίνησίς ἐστιν. ἀλλ᾽ ἕτερον ἀνάγκη κινούμενον εἶναι κατὰ φορὰν πρότερον, ὃ Kal τῆς γενέσεως αἴτιον ἔσται τοῖς γιγνομένοις, οὐ γιγνόμενον, οἷον τὸ γεννῆσαν τοῦ γεννηθέντος. ἐπεὶ δόξειέ γ᾽ ἂν ἡ γένεσις εἶναι πρώτη τῶν κινήσεων διὰ τοῦτο, ὅτι γενέσθαι δεῖ τὸ πρᾶγμα 5 πρῶτον." τὸ δ᾽ ἐφ᾽ ἑνὸς μὲν ὁτουοῦν τῶν γιγνομένων οὕτως ἔχει, ἀλλ᾽ ἕτερον ἀναγκαῖον πρότερόν τι πε ρος σφ κς Ὡς τὸ τοις α 2,6. either the same motion must go on continuously or different motions must succeed one another without a pause.
¢ Animals and plants are primarily in Aristotle’s mind. ἃ As manifested by self-movers.
Thus (1) since motion must necessarily go on without intermission, and to do so must either be continuous or successive,* of which continuity is to be preferred as the better, and since we must always assume the better, if it be not impossible, to be what actually occurs in nature, and since (as will be demonstrated hereafter,? and may be assumed meanwhile) continuity is not impossible in this case, and no other but local motion can be continuous, it follows that local motion has the priority in the first sense. For the fact that a thing is changing its place is no reason why it should also be growing or changing its qualities, or coming into existence or vanishing out of it; whereas none of these other changes could take place, were it not for the continuous motion which the prime mover causes.
Further (2) it is first in time, for it is the only motion of which things eternal are capable. It is true that if we take any one individual thing that comes into being and vanishes out of 10,9 local movement must be the last which it experiences, for after it has begun to exist modification and growth are the first to set in, whereas local motion ὦ is the characteristic movement of the ‘accomplished’ creature. On the other hand, all this must be preceded by some other cause which is locally in motion and acts as the cause of things coming into existence without itself being in process of coming into existence, as we see in the case of the begetter and the begotten. It might seem that genesis could claim the priority amongst movements, on the ground that the thing moust be generated before all else; but though this is so with respect to any one thing that comes to be, yet something which is not coming into existence 2618 κινεῖσθαι τῶν γιγνομένων ov αὐτὸ καὶ μὴ γιγ- νόμενον, καὶ τούτου ἕτερον πρότερον. ἐπεὶ δὲ γένεσιν ἀδύνατον εἶναι πρώτην (πάντα yap ἂν εἴη τὰ κινούμενα φθαρτά), δῆλον ws οὐδὲ τῶν ἐφεξῆς 10 κινήσεων οὐδεμία προτέρα---λέγω δ᾽ ἐφεξῆς αὔξησιν, εἶτ᾽ ἀλλοίωσιν καὶ φθίσιν καὶ φθοράν---πᾶσαι γὰρ ὕστεραι γενέσεως, ὥστ᾽ εἰ μηδὲ γένεσις προτέρα φορᾶς, οὐδὲ τῶν ἄλλων οὐδεμία μεταβολῶν. A A Ὅλως δὲ φαίνεται τὸ γιγνόμενον ἀτελὲς καὶ ἐπ᾽ ἀρχὴν ἰόν, ὥστε TO TH γενέσει ὕστερον TH φύσει ,ὔ Ss “a A 4 van ς / πρότερον εἶναι. τελευταῖον δὲ dopa πᾶσιν ὑπάρχει 1s Tots ev γενέσει. διὸ τὰ μὲν ὅλως ἀκίνητα τῶν ζώντων δι᾽ ἔνδειαν τοῦ ὀργάνου, οἷον τὰ φυτὰ καὶ πολλὰ γένη τῶν ζῴων, τοῖς δὲ τελειουμένοις ὑπάρχει. ὥστ᾽ εἰ μᾶλλον ὑπάρχει φορὰ τοῖς μᾶλλον ἀπειληφόσι τὴν φύσιν, καὶ ἡ κίησις αὕτη πρώτη τῶν ἄλλων ἂν εἴη κατ᾽ οὐσίαν, διά τε ταῦτα 20 Καὶ διότι ἥκιστα τῆς οὐσίας ἐξίσταται τὸ κινού- μενον τῶν κινήσεων ἐν τῷ φέρεσθαι" κατὰ μόνην γὰρ οὐδὲν μεταβάλλει τοῦ εἶναι, ὥσπερ ἀλλοιου- μένου μὲν τὸ ποιόν, αὐξανομένου δὲ Kat φθίνοντος τὸ ποσόν. μάλιστα δὲ δῆλον ὅτι τὸ κινοῦν αὐτὸ PHYSICS, VIII. viz.
but actually exists must in every case have been already moving before the inception of the thing which is coming into existence, and another again before that other. And since genesis cannot have been the absolute first (for if so all moving things would be perishable), it is clear that neither can any of the movements next in order (by which I mean growth, modification, decay, and passing away) take the precedence, since they are all subsequent to genesis; so that if genesis does not precede local movement neither can any of the other forms of change do so.
Finally (3), taking broad ground, we may say that anything which is in process of coming into being proclaims itself as imperfect, and as making for some constituent principle which is already there in the nature of things, so that what it comes to last in its own genesis precedes it in the order of nature. Now local movement is the final characteristic that manifests itself in generated creatures. This is why some living creatures, such as plants and many kinds of animals, cannot move for lack of the appropriate organ, while others possess the power as they come to perfection. So if local movement characterizes things in proportion to the fulness of nature they have realized, this same kind of movement should take precedence of all others in respect of perfection of nature. And besides this, there is another reason, namely, that of all kinds of change local movement is the one which takes its subject least away from its essential nature, for it is the only one that affects no intimate characteristic, as modification affects quality and growth or shrinkage quantity. But most convincing of all is the fact that it is just this local move- 261825 αὑτὸ μάλιστα ταύτην κινεῖ κυρίως THY κατὰ τόπον' καίτοι φαμὲν τοῦτ᾽ εἶναι τῶν κινουμένων καὶ κινούντων ἀρχήν, καὶ πρῶτον τοῖς κινουμένοις τὸ αὐτὸ αὑτὸ κινοῦν.
τι μὲν τοίνυν τῶν κινήσεων ἡ φορὰ πρώτη, φανερὸν ἐκ τούτων" Tis δὲ φορὰ πρώτη, νῦν δεικτέον. ἅμα δὲ Kal τὸ viv καὶ πρότερον ὑποτεθέν, ὅτι 80 ἐνδέχεταί τινα κίνησιν εἶναι συνεχῆ Kal ἀΐδιον, φανερὸν ἔσται τῇ αὐτῇ μεθόδῳ. τι μὲν οὖν τῶν ἄλλων κινήσεων οὐδεμίαν ἐνδέχεται συνεχῆ εἶναι, ἐκ τῶνδε φανερόν. ἅπασαι γὰρ ἐξ ἀντικειμένων εἰς ἀντικείμενά εἶσιν at κινή- σεις καὶ μεταβολαΐί--οἷον γενέσει μὲν καὶ φθορᾷ 8 τὸ ὃν καὶ TO μὴ OV ὅροι, ἀλλοιώσει δὲ τἀναντία πάθη, αὐξήσει δὲ καὶ φθίσει ἢ μέγεθος καὶ μι- κρότης ἢ τελειότης μεγέθους καὶ ἀτέλεια---ἐναντίαι 261} δ᾽ αἱ εἰς τὰ ἐναντία. τὸ O€ μὴ ἀεὶ κινούμενον τήνδε τὴν κίνησιν, ὃν δὲ πρότερον, ἀνάγκη πρότερον ἠρεμεῖν. φανερὸν οὖν ὅτι ἠρεμήσει ἐν τῷ ἐναντίῳ τὸ μεταβάλλον. ὁμοίως δὲ καὶ ἐπὶ τῶν μεταβολῶν: ὃ Such as hot and cold, light and heavy.
¢ [Hence its change cannot be continuous.—C.]
ἃ ἘΡ 225 a 31. Every ‘movement’ (κίνησις, 2.6. change of quality, quantity, or place) is a ‘change’ (aeasansy: becoming and perishing are ὁ changes,’ not ‘ movements.’— * ment and no other which is, properly speaking, made by the self-mover as such; and it is just this selfmover that we have pronounced to be the principle, amongst things that are both in motion themselves and causes of motion in others, and the initiator of the movement of moving things.
That local motion takes precedence of the other motions has thus been demonstrated, and we must now go on to show what form of local movement itself takes precedence of the others; in the course of which investigation we shall demonstrate what we have, in the present context and earlier,? laid down provisionally as to the possibility of there actually being a continuous and eternal movement.
To begin with, it is clear from the following considerations that no progression other than local move- — ment can be continuous and perpetual. All the other progressions or changes are between one term and its opposite—for instance, existence and non-existence are the limiting terms of genesis and evanishment 5 the extremes either way are the limits of qualitative modifications >; and the greatest and least possible size, or maximum approach to, or defect from, the perfect norm of size, are the limits of growth and shrinkage — and movements directed to opposite limits are opposite to each other. Now a mobile which has not always been subject to a given movement, but was in existence before it began it, must then have been exempt from that movement; so it is clear that that movement of the changing thing will cease when it reaches either extreme.“ And so too with (pure) changes (that are not movements %); 8618 ἀντίκειται yap ἡ φθορὰ καὶ γένεσις ἁπλῶς Kal ἡ καθ᾽ ἕκαστον τῇ καθ᾽ ἕκαστον: ὥστ᾽ εἰ ἀδύνατον ἅμα μεταβάλλειν τὰς ἀντικειμένας, οὐκ ἔσται συνεχὴς ἢ μεταβολή, ἀλλὰ μεταξὺ ἔσται αὐτῶν χρόνος. οὐδὲν yap διαφέρει ἐναντίας ἢ μὴ ἐναντίας εἶναι Tas κατ᾽ ἀντίφασιν μεταβολάς, εἰ μόνον 10 ἀδύνατον ἅμα TH αὐτῷ παρεῖναι: τοῦτο yap τῷ oym οὐδὲν χρήσιμον: οὐδ᾽ εἰ μὴ ἀνάγκη ἠρεμῆσαι ἐν τῇ ἀντιφάσει, μηδ᾽ ἐστὲ μεταβολῇ ἠρεμία" ἐναντίον —ov yap ἴσως ἠρεμεῖ τὸ μὴ ὄν: ἡ δὲ φθορὰ εἰς τὸ μὴ ὄν---ἀλλ᾽ εἰ μόνον μεταξὺ γίγνεται χρόνος" οὕτω yap οὐκ ἔστιν ἡ μεταβολὴ συνεχής" οὐδὲ γὰρ ἐν 15 τοῖς πρότερον ἡ ἐναντίωσις χρήσιμον, ἀλλὰ TO μὴ ἐνδέχεσθαι ἅμα ὑπάρχειν. od δεῖ δὲ ταράττεσθαι ὅτι τὸ αὐτὸ πλείοσιν ἔσται ἐναντίον, οἷον ἡ κίνησις καὶ στάσει Kal κινήσει TH εἰς τοὐναντίον, ἀλλὰ μόνον τοῦτο λαμβάνειν, ὅτι ἀντίκειταί πως καὶ τῇ κινήσει Kal TH ἠρεμίᾳ ἡ κίνησις ἡ ἐναντία 00 (καθάπερ τὸ ἴσον καὶ τὸ μέτριον τῷ ὑπερέχοντι καὶ τῷ ὑπερεχομένῳ), καὶ ὅτι οὐκ ἐνδέχεται ἅμα τὰς ἀντικειμένας οὔτε κινήσεις οὔτε μεταβολὰς ὑπάρχειν. ἔτι δ᾽ ἐπί τε τῆς γενέσεως Kal τῆς φθορᾶς καὶ παντελῶς ἄτοπον ἂν εἶναι δόξειεν, εἰ 1 [μεταβολῇ ἠρεμία HI, Oxf. Trans.: μεταβολὴ ἠρεμίᾳ cett.
“πα: PHYSICS, VIII. vi.
for genesis and evanishment taken absolutely are absolute opposites, and any specific genesis and evanishment are specifically opposite to each other; and so, since nothing can be changing in opposite directions at the same time, a change in neither direction can be continuous, but there must be an interval of time between any two stretches of it. Nor does it make any difference whether you count these contradictory changes amongst ‘ contraries * or not, for in any case, as long as changes in the two directions cannot coexist, this point does not affect the argument. Nor does it matter if there is no necessity for the thing to come to rest in the contradictory state, or if there is no state of rest opposed to the change: evanishment is passing into nonexistence, and it may be true that the non-existent is not in a state of rest. All that matters is that there should be an interval of time; for then the change is not continuous, just as in the other cases of change what mattered was not the contrariety between them but that they could not both occur in the same thing at the same time. Nor need we be troubled by one and the same thing being the contrary of more things than one, for instance one motion being opposed to ‘ station’ and also to the opposite motion. We may be content to take it that a motion may be opposed, under a certain aspect, either to the contrary motion or to absence of motion, just as equality or the mean may be contrasted either with what is short of it or what it is short of, and that neither opposite movements nor opposite changes can coexist in the same subject. Moreover, in the case of genesis and evanishment, it would surely be too monstrous to suppose that a thing must vanish 261 b γενόμενον εὐθὺς ἀνάγκη φθαρῆναι καὶ μηδένα 25 χρόνον διαμεῖναι" ὥστε ἐκ τούτων ἂν ἡ πίστις γένοιτο ταῖς ἄλλαις" φυσικὸν γὰρ τὸ ὁμοίως ἔχειν ἐν πάσαις.
We shall now show that everlasting, uniform and uninterrupted motion does exist and that it is of necessity All local motion is either circular or rectilinear or a combination of these; therefore if either of these is incapable of being continuous no combination of them can be so. Rectilinear motion cannot be continuous (i.e. uniform, uninterrupted and everlasting), because the mobile that goes on moving when it reaches the end of the line divides its motion into two specifically different ones by turning back and reversing the direction. Motion on a continuous path is continuous as long as the mobile does not stop moving. But if it does stop and then go on again, the point at which tt does so marks the end of one movement and the beginning of another. Motion is hindered by the mobile pausing at, but not by its passing through, a point on its path. The pause makes the point function dually as the end of one movement and the beginning of another; the mobile ‘ arrives there’ at the end of the first and ‘departs thence’ at the beginning of the second movement, but not during one continuous movement.
This analysis does not apply to a point at which the mobile turns back, for no pause 15 needed to give this point the double function of the end of, say, a forward and the beginning of a backward movement; and the mobile ‘ arrives there’ at the end of the first and ‘ departs thence’ at the beginning of the second movement just as much as in the former case, although the arrival and departure are here simultaneous (Ὁ 28-263 41). [The difficulties suggested by the simultaneous arrival and departure are dealt with at 263 b 9 sqq 1 PHYSICS, VIII. vir.—-vwi1t.
at the very instant of coming into existence and not endure any time at all. This would plead, on the principle of analogy that runs through nature, for the belief that it is so in all the other cases.
ARGUMENT (continued) Conclusion: that rectilinear motion cannot go on for ever without interruption (a 1-8).
The parallelism between time and space which solves Zeno’s Achilles and dichotomy dilemmas, as presented in Bk. WI. chs. ui. and ix., does not touch the question of the passage of time itself: this is now shown to be a case of the distinction between the potential and the actual: it is impossible to count (or to go through) an illimitable number of actual points (or periods) of time but not impossible to count or go through a period whose potential divisibility is illimitable, if its actual extent and the actual number of its parts are limited (a 3-b 9).
The instant which divides the past and future time per-Jorms a double function: end of the past and beginning of the future. But the point that divides states that counteract each other—so that the object is always in ether the one or the other—has not a dual function, for to end the one is to begin the other; therefore at that point of time it is the other, and has done being the first. So that instant belongs to the future and not to the past (b 9-264 a 6).
Other considerations which also lead to the conclusion that no rectilinear movement can be everlasting, uniform and uninterrupted: (1) anything that moves continuously is making for its goal from the beginning, but a mobile which reverses the direction of its motion, moves away from what it was formerly moving towards; if then reverse movements were continuous, 1t would still be moving towards what it was now moving away from, which is impossible. (2) Anything capable of moving is capable of resting from motion, So ARGUMENT (continued) and as a thing cannot move in opposite directions simultaneously it must rest from motion in one direction while moving in the opposite one.
Another example of (1) in respect to change of quality Continuity of tume does not involve continuity of modification: for without pausing, a mobile can reverse the direction of its motion and thereby break the continuity of the modification (b 6-9).