Lectio 4 Lecture 4 Solvuntur rationes, ex quibus sequi videtur quod motus non semper fuerit Refutation of arguments seeming to prove motion is not eternal Contraria autem his non difficile est solvere. The arguments that may be advanced against this position are not difficult to dispose of. Videbitur autem ex huiusmodi considerantibus, contingere maxime motum esse aliquando, cum non esset omnino. The chief considerations that might be thought to indicate that motion may exist but at one time it had not existed at all are the following. Primum quidem, quia neque una perpetua mutatio est. Mutatio enim omnis apta nata est ex quodam in quiddam: quare necesse est omnis mutationis terminum esse contraria in quibus fit: in infinitum autem moveri nullum. First, it may be said that no process of change is eternal. For the nature of all change is such that it proceeds from something to something, such that every process of change must be bounded by the contraries that mark its course, and no motion can go on to infinity. Amplius, videmus quoniam possibile est moveri, quod neque movetur neque habens in seipso neque unum motum; Second, we see that a thing that neither is in motion nor contains any motion within itself can be set in motion. ut in inanimatis, quorum neque pars ulla neque totum movetur, sed quiescens movetur quandoque. For instance, inanimate things that are not in motion but at rest (whether the whole or some part is in question) are at some moment set in motion; Convenit autem aut semper moveri aut nequaquam, si quidem non fit cum non sit. but if motion cannot have a becoming before which it had no being, these things ought to be either always in motion or never. Multo autem magis huiusmodi esse in animatis manifestum est. Third, the fact that motion is not eternal is evident above all in the case of animate beings. Neque enim unus quidem in nobis cum sit motus aliquando, sed quiescentes tamen movemur aliquando, et fit in nobis ex nobis ipsis principium motus aliquando, etsi nihil extra moveat. For sometimes there is no motion in us and we are quite still and nevertheless we are then at some moment set in motion—that is to say, sometimes we produce a beginning of motion in ourselves spontaneously without anything having set us in motion from without. Hoc enim in inanimatis esse non videmus similiter, sed semper movet ipsa aliquid exteriorum alterum: We see nothing like this in the case of inanimate things, which are always set in motion by something else from without. animal autem dicimus ipsum se movere. Quare, si quiescit aliquando penitus, in immobili motus utique fiet ex ipso et non ab extra. The animal, on the other hand, we say, moves itself; therefore, if an animal is ever in a state of absolute rest, we have a motionless thing in which motion can be produced from the thing itself, and not from without. Si autem in animali hoc possibile fieri, quid prohibet idem accidere et secundum omne? Now, if this can occur in an animal, why should not the same be true also of the universe as a whole? Si namque in parvo mundo fit, et in magno; et si in mundo, et in infinito: si quidem contingit moveri infinitum et quiescere totum. If it can occur in a small world it could also occur in a great one, and if it can occur in the world, it could also occur in the infinite; that is, if the infinite could as a whole possibly be in motion or at rest. Horum autem primum quod dictum est, non eundem semper et unum numero esse motum qui est in contraria, recte dicitur. Of these objections, then, the first mentioned—that motion to opposites is not always the same and numerically one—is a correct statement. Hoc enim fortassis quidem necessarium est: siquidem non semper unum et eundem esse possibile est eiusdem et unius motum. In fact, this may be said to be a necessary conclusion, provided that it is possible for the motion of that which is one and the same to be not always one and the same. Dico autem sicut utrum unius chordae unus et idem sonus, aut semper alter, similiter se habente et movente. (I mean that, for instance, we may question whether the note given by a single string is one and the same or is different each time the string is struck, although the string is in the same condition and is moved in the same way.) Sed tamen, qualitercumque se habet, nihil prohibet quendam eundem esse, qui continuus et perpetuus est. Manifestum autem erit magis ex his quae posterius. But still, however this may be, there is nothing to prevent there being a motion that is the same in virtue of being continuous and eternal; we shall have something to say later that will make this point clearer. Moveri autem quod non movetur, nullum inconveniens est, si aliquando quidem sit extrinsecus movens, aliquando autem non. As regards the second objection, no absurdity is involved in the fact that something not in motion may be set in motion, that which caused the motion from without being at one time present and at another absent. Hoc autem quomodo utique erit, inquirendum est: dico autem ut idem ab eodem motivo existente, aliquando quidem moveatur, aliquando autem non. Nihil enim aliud dubitat hoc dicens, quam propter quid non semper alia quidem quiescunt eorum quae sunt, alia vero moventur. Nevertheless, how this can be so remains matter for inquiry—how it comes about, I mean, that the same motive force at one time causes a thing to be in motion and at another does not do so. For the difficulty raised by our objector really amounts to this: why is it that some things are not always at rest, and the rest always in motion? Maxime autem videbitur tertium habere dubitationem quod fit cum non insit prius motus, quod accidens est in animatis: quiescens enim prius, post hoc vadit, movente exteriorum nullo, sicut videtur. The third objection may be thought to present more difficulty than the others, namely, the objection that alleges that motion arises in things in which it did not exist before, adducing as proof the case of animate things: an animal is first at rest and afterwards walks, not having been set in motion perhaps by its surroundings. Hoc autem falsum est: conspicimus enim semper aliquid motum in animali naturalium; huius autem motus non animal causa est, sed continens forsitan. This, however, is false, for we observe that there is always some part of the animal’s organism in motion, and the cause of the motion of this part is not the animal itself, but possibly its environment. Ipsum autem dicimus seipsum movere non secundum omnem motum, sed secundum locum. Nihil igitur prohibet, magis autem fortassis necessarium est, in corpore multos fieri motus a continente; horum autem quosdam intellectum aut appetitum movere; illum autem totum iam animal movere. Moreover, we say that the animal itself originates not all of its motions, but its locomotion. So, it may well be the case—or rather we may perhaps say that it must necessarily be the case—that many motions are produced in the body by its environment and some of these set in motion the intellect or the sensible appetite, and that this again then sets the whole animal in motion. Quale contingit circa somnos: sensibilis quidem enim cum neque unus insit motus, inexistente tamen aliquo, surgunt animalia iterum. Sed namque manifestum erit et de his ex sequentibus. This is what happens when animals are asleep: though there is then no perceptive motion in them, there is some motion that causes them to wake up again. But we will leave this point also to be elucidated at a later stage in our discussion. 997. Postquam Philosophus posuit rationes ad probandum motum semper esse, hic intendit solvere ea quae in contrarium obiici possunt. 997. After giving arguments proving that motion always exists, the Philosopher now intends to answer objections to the contrary. Et circa hoc duo facit: About this, he does two things: primo ponit rationes; first, he gives the arguments; secundo solvit eas, ibi: horum autem primum etc. second, he answers them, at of these objections (252b28; [1000]). Circa primum ponit tres rationes, praemittens suam intentionem: et dicit quod ea quae in contrarium obiici possunt, non est difficile solvere. Ex tribus enim rationibus videtur maxime sequi quod motus aliquando incipiat esse, cum prius omnino non fuerit: In regard to the first, he gives three arguments, after first stating that it is not difficult to solve the objections contrary to his position. And he says that there are three main arguments from which it seems to follow that motion began to be at some time after previously not existing at all. quarum prima est, qua supra probavit in sexto quod nulla mutatio est infinita; eadem enim ratione probari potest quod nulla mutatio sit perpetua. Nulla enim mutatio terminata est perpetua, sicut nec infinita; sed omnis mutatio est terminata. Omnis enim mutatio naturaliter est ex quodam in quiddam, et ista duo sunt contraria; unde necesse est quod terminus cuiuslibet mutationis sint ipsa contraria in quibus fit transmutatio. Sed quia non in omni motu locali manifesta est contrarietas terminorum, subiungit quod est commune omni motui, quod nihil movetur in infinitum; quia nihil movetur ad id ad quod pertingere non potest, ut in sexto dictum est. Sic ergo patet quod nulla mutatio est perpetua, sicut nec infinita. Si ergo nulla mutatio est perpetua, videtur etiam possibile dari tempus in quo nulla mutatio sit. Et haec prima ratio accepta est ex parte motus. The first of these is that whereby he proved in book 6 that no change is infinite, because by the same argument, it can be proved that no change is eternal. For no terminated change is eternal any more than it is infinite. But every change is terminated. For every motion is naturally from something to something, and these two are contraries; hence, of necessity, the termini of any change are the contraries within the sphere of that change. But, because contrariety of termini is not evident in all cases of local motion, Aristotle adds something common to every motion, namely, that nothing is moved to infinity, because nothing is moved to what it cannot reach, as has been said in book 6. Accordingly, it is clear that no motion is perpetual, just as it is not infinite. If, therefore, no motion is perpetual, it also seems possible to posit a time in which there is no change. This first argument is taken from motion. 998. Secunda ratio accipitur ex parte mobilis, quam ponit ibi: amplius videmus etc.; quae talis est. Si motus non potest fieri de novo cum prius non esset, videtur esse conveniens dicere de unoquoque, quod vel semper movetur, vel nequaquam moveatur: quia si in uno mobili potest quandoque motus esse et quandoque non esse, pari ratione in toto universo. Sed videmus quod possibile est aliquid moveri, quod prius non movebatur secundum totum, neque aliquem motum in seipso habebat secundum aliquam sui partem: sicut apparet in rebus inanimatis, in quibus aliquod mobile quandoque moveri incipit, cum antea nulla pars eius moveretur, neque ipsum totum, sed omnino quiesceret. Relinquitur ergo quod in toto universo potest esse motus, cum prius non fuerit. 998. The second argument is based on the mobile, at second, we see (252b12). If motion cannot newly come to be when previously it was not, it seems fitting to say of anything that it is either always in motion or never in motion. For if motion can sometimes be and sometimes not be in one particular mobile, why not for the whole universe? But we see that it is possible for something to be moved that previously was not moved as a whole and that had no motion in itself with respect to any of its parts, as is apparent in non-living things, among which some mobile begins at one time to be moved when previously no part nor the whole had been moved, but it was completely at rest. Thus, it remains that, in the whole universe, there can be motion where previously there was none. 999. Sed quia in rebus inanimatis, licet appareat motus in aliquo de novo incipere nullo motu praeexistente in illo eodem, apparet tamen motus praeexistens in aliquo exteriori a quo movetur: ideo tertiam rationem ponit ex parte animalium, quae non moventur ab extrinseco, sed a seipsis; et hoc ibi: multo autem magis etc. 999. But, because in non-living things, even though motion is seen to begin anew in something when previously there was none at all, yet motion appears to have been preexisting in something external by which it is moved, he accordingly gives a third argument from animals, which are moved not from without but by themselves. This argument is at third, the fact (252b17). Et dicit quod incipere motum cum prius non esset, multo magis est manifestum in rebus animatis quam inanimatis. And he says that it is more evident in animals than in the non-living that motion begins after previously having not existed. Cum enim nos quieverimus aliquando, nullo motu in nobis existente, aliquando moveri incipimus, et est ex nobis ipsis principium nostri motus, etiam si nihil extrinsecum moveat: For when we have rested for a time such that no motion exists in us, we begin at a certain time to be moved, and the principle of our motion is from our very selves even if nothing external moves us. quod quidem in rebus inanimatis non contingit, sed semper aliquid extrinsecum movet ipsa, vel generans, vel removens prohibens, vel violentiam inferens. This, however, does not happen in non-living things, because they are moved always by something external, such as the cause that generates them, or a cause that removes an obstacle, or a cause that subjects them to force. Ex quo sequitur quod si animal quandoque totaliter quiescat, quod in aliquo immobili incipiat esse motus cum prius non fuerit, non ex aliquo extrinseco movente, sed ab ipsomet quod movetur. Et si hoc potest esse in animali, nihil prohibere videtur quin idem accidat in universo: habet enim animal, et maxime homo, similitudinem quandam cum mundo: unde dicitur a quibusdam quod homo sit parvus mundus. Et sic si in parvo mundo incipit motus cum prius non fuerit, videtur quod etiam in magno mundo idem possit contingere. Et si hoc contingit in mundo, potest etiam contingere in toto infinito, quod quidam posuerunt extra mundum: si tamen sit aliquod infinitum quod possit quiescere et moveri. It follows from this that, if an animal is at one time entirely at rest, then motion begins to exist in an immobile being after previously not existing in it and the motion does not originate from an external mover, but from the very thing that is moved. And, if this can occur in an animal, there is nothing to prevent its occurring in the universe. For an animal, and especially man, possesses a likeness to the world; therefore, it is said that man is a small world. Accordingly, if, in this small world, motion can begin after previously not existing in it, it seems that the same can happen in the large world. And, if this happens in the world, it can happen in the infinite whole, which some assumed exists beyond the world—provided, of course, that there is something infinite that can rest and be moved.