Authors/Thomas Aquinas/physics/L4/lect10

Lecture 10 The meaning of “void”—refutation of those positing the void

Latin	English
	Lecture 10 The meaning of “void”—refutation of those positing the void
lib. 4 l. 10 n. 1 Dixerat superius philosophus a tribus esse incipiendum: postquam ergo prosecutus est duo eorum, ponens scilicet opiniones negantium et affirmantium vacuum esse, hic prosequitur tertium, communes scilicet opiniones hominum de vacuo demonstrans. Circa hoc igitur tria facit: primo ostendit quid significetur nomine vacui; secundo ostendit quomodo vacuum aliqui esse posuerunt, ibi: quoniam autem de loco etc.; tertio excludit rationes ponentium vacuum esse, ibi: neque una autem et cetera. Circa primum duo facit: primo dicit de quo est intentio; secundo exequitur propositum, ibi: videtur autem et cetera.	506. The Philosopher had said above that we I must start with three things. So now, having finished two of them, by giving, namely, the opinions of both of those who posited and of those who rejected the void, he now enters upon the third, by showing, namely, the general notions people have about the void. Concerning this he does three things: First he shows what is meant by the word “void”; Secondly, how some thought that the void exists, at no. 513; Thirdly, he rejects the reasons given by those who posit that a void exists, at no. 515. As to the first he does two things: First he reveals his intention; Secondly, he executes it, at no. 509.
lib. 4 l. 10 n. 2 Dicit ergo primo quod, cum dictum sit quod quidam posuerunt vacuum esse, quidam vero negaverunt; ad cognoscendum qualiter se habeat veritas, oportet accipere tanquam principium, quid significet nomen vacui. Sicut enim cum dubitatur an aliqua passio insit alicui subiecto, oportet accipere pro principio quid sit res, ita cum dubitatur de aliquo an sit, oportet accipere pro medio quid significet nomen. Quaestio enim quid est sequitur quaestionem an est.	507. He says first, therefore [349 213 b30], that since it was pointed out that some people affirmed a void and others denied it, in order to get at the truth we must begin by the meaning of the word “void.” For just as, when there is question about some property existing in a subject, we must begin by agreeing what the thing is, so when there is question about the existence of something, we must begin by taking as the middle form the meaning of the word. For the question of what something is comes after the question of whether it exists.
lib. 4 l. 10 n. 3 Deinde cum dicit: videtur autem vacuum etc., ostendit quid significet nomen vacui: et primo ponit significationem communiorem; secundo significationem secundum usum Platonicorum, ibi: alio autem modo et cetera. Circa primum tria facit: primo ostendit quid significet nomen vacui; secundo quid oportet addere ad illam significationem, ibi: sed inconveniens est etc., tertio removet quandam dubitationem, ibi: unde et si et cetera.	508. Then [350 213 b31] he shows that it meant by the word “void”. First he gives the more common meaning; Secondly, what the Platonists took it to mean at no. 512. As to the first he does three things: First he shows what the word “void” means; Secondly, what should be added to that meaning at no. 510; Thirdly, he clears up a doubt, at no. 511.
lib. 4 l. 10 n. 4 Dicit ergo quod secundum opinionem hominum, videtur vacuum nihil aliud significare quam locum in quo nihil sit. Et huius causa est, quia proprie vacuum dicitur esse, in quo non est aliquod corpus: quia soli corpori convenit quod sit in loco; et vacuum nihil aliud potest significare quam locum absque locato. Sed quia homines opinantur quod omne ens sit corpus, sequitur secundum eorum opinionem quod ubi non est corpus, nihil sit. Et ulterius opinantur quod omne corpus sit tangibile, id est habens tangibiles qualitates. Et huiusmodi corpus est quod est grave vel leve: nondum enim erat notum quod corpus caeleste esset praeter naturam quatuor elementorum. Unde cum proprie de ratione vacui sit quod sit locus in quo non est aliquod corpus, sequitur quod vacuum sit in quo non est corpus grave vel leve: non quidem quod hoc sit de ratione vacui secundum primam impositionem nominis, sed secundum quandam syllogisticam deductionem ex communi opinione hominum, opinantium omne corpus esse grave vel leve: sicut etiam secundum opinionem communem hominum existimantium omne ens esse corpus, sequitur vacuum esse in quo nihil est. Sic igitur tribus modis potest accipi huius nominis significatio: una est propria, scilicet vacuum est locus in quo non est corpus: aliae duae secundum opinionem hominum; quarum una est communior, scilicet vacuum est locus in quo nihil est; alia vero est magis coarctata, scilicet vacuum est locus in quo non est corpus grave vel leve.	509. He says therefore that according to common opinion, the void seems to signify nothing more than a place In which there is nothing. The reason for this is because properly that is said to be a void in which there is not any body, and since only a body can be in place, void seems to mean nothing more than a place without any thing in it. But because people suppose that every being is a body, it follows that according to their opinion where there is not body, there is nothing. And further they believe that every body is tangible, i.e., that it has tactile qualities. And a body of this kind is heavy or light: for in their time it was not yet known that a heavenly body is different in nature from any of the four elements. Hence since it is the very nature of the void to be a place in which there is not a body, it follows that the void is that in which there is neither a light nor a heavy body. However, this is not to say that it belongs to the notion of the void according to the primary meaning of the word, but rather by reason of a certain syllogistic deduction that starts with the general opinion of people that every body is either heavy or light; just as the common opinion of people that every being is a body, leads to the conclusion that the void is that in which there is nothing. Consequently, the meaning of this word “void” is three-fold: one is proper, namely, that the void is that in which there is not any body; the others come from the general opinion of people: the first is more common, namely, that the void is a place in which nothing exists; the second is more restricted, namely, that the void is a place in which there is neither a heavy nor a light body.
lib. 4 l. 10 n. 5 Deinde cum dicit: sed inconveniens est etc., ostendit quid addendum sit ad hanc significationem. Dicit enim quod inconveniens est si dicatur quod punctum sit vacuum, cum tamen de puncto dici possit quod in puncto non sit corpus tangibile. Oportet ergo addere quod vacuum sit locus in quo non sit corpus tangibile, sed sit ibi spatium susceptivum corporis tangibilis: sicut caecum dicitur quod caret visu, natum autem habere. Et sic concludit quod uno modo dicitur vacuum, spatium quod non est plenum corpore sensibili secundum tactum, quod scilicet est grave vel leve.	510. Then [351 214 a4] he shows that must be added to this meaning. For he says that it is not correct to say that a point is a void, even though in a point there is no tangible body. So we must add that the void to a place in which there is not a tangible body, but which has in it space to receive a tangible body, just as a blind person is said to be one who lacks sight but to apt to have it. And so he concludes that in one way the void is called a space which is not full of a body that is sensible by touch, i.e., a body that is heavy or light.
lib. 4 l. 10 n. 6 Deinde cum dicit: unde et si dubitabit aliquis etc., removet quandam dubitationem, quae est: utrum si in aliquo spatio sit color vel sonus, dicendum sit vacuum vel non: et hoc propter definitionem primo datam, scilicet vacuum est in quo nihil est. Et solvit quod si spatium in quo est tantum sonus vel color, sit susceptivum corporis tangibilis, vacuum est: si vero non, non est vacuum. Et hoc ideo, quia haec non est propria definitio vacui, vacuum est in quo nihil est, nisi secundum opinionem credentium, ubi non est corpus nihil esse.	511. Then [352 214 a9] he clears up the following difficulty; If there is color or sound in a certain space, should it be called a void or not? This question arises because the definition first given says that the void is that in which there is nothing. And he answers by saying that if the space in which there is just sound or color has room for a tangible body, it is a void; if not, not. The reason is that the proper definition of the void is not “that in which there is nothing,” and such a definition is held only by people who believe that where no body is, nothing is.
lib. 4 l. 10 n. 7 Deinde cum dicit: alio autem modo etc., ponit aliam significationem vacui secundum usum Platonicorum. Et dicit quod alio modo dicitur esse vacuum: in quo non est hoc aliquid, neque aliqua substantia corporea. Fit autem hoc aliquid per formam. Unde aliqui dicunt materiam corporis, secundum quod est absque forma, esse vacuum: qui etiam materiam dicunt esse locum, ut supra dictum est. Sed non bene dicunt: quia materia non est separabilis a rebus quarum est materia; sed homines quaerunt locum et vacuum, tanquam aliquid separabile a corporibus locatis.	512. Then [353 214 a11] he gives the meaning of “void” as used by the Platonists. And he says that there is another meaning of the void: that in which there is no “this something” or any corporeal substance. Now a “this something” comes about on account of the form. Hence some claim that the matter of a body, insofar as it is apart from its form, is the void. These are the same who claim that matter is place, as was stated above (L.3). But this is poor judgment, for matter is not separable from the things of which it is the matter; whereas men inquire about place and the void as being separable from bodies in place.
lib. 4 l. 10 n. 8 Deinde cum dicit: quoniam autem de loco etc., ostendit quomodo aliqui ponebant vacuum esse. Et primo quid dicebant esse vacuum; secundo propter quid vacuum ponebant, ibi: et propter eadem acceptum et cetera. Dicit ergo primo, quod quia vacuum est locus privatus corpore, et determinatum est de loco quomodo sit et quomodo non sit (dictum est enim quod locus non est aliquod spatium, sed terminus continentis); manifestum est etiam quod neque vacuum est spatium separatum a corporibus, neque intrinsecum corporibus, sicut ponebat Democritus. Et hoc ideo, quia ponentes vacuum quocumque istorum modorum, volunt quod vacuum non sit corpus, sed spatium corporis. Ideo enim videbatur aliquid esse vacuum, quia locus aliquid est: et sicut locus videbatur esse spatium, ita et vacuum. Si ergo locus non est aliquod spatium praeter corpora, neque vacuum potest esse spatium praeter corpora. Et cum de ratione vacui sit quod sit spatium corporis praeter corpora, ut supra dictum est, sequitur quod vacuum non sit.	513. Then [354 214 a16] he tells how some posited existence of a void; First, what they said the void was; Secondly, why they posited it, at no. 514. He says therefore first that since the void is a place without a body in it, and since we have already decided how place exists and how it does not (for we have said that place is not a space but the boundary of a container), it is clear that the void is neither a space separated from bodies nor intrinsic to them as Democritus supposed. This is so because those who suppose that space exists in either of those two ways, intend the void to be not a body, but the space of a body. For they thought that the void was something because place was something, and just as place seems to be space, so also the void. But if place is not a space outside of bodies, neither can the void be a space outside of bodies. And since it is the very nature of the void to be a bodily space existing outside of bodies, as was said above, it follows that the void does not exist.
lib. 4 l. 10 n. 9 Deinde cum dicit: et propter eadem acceptum etc., ostendit quare posuerunt vacuum. Et dicit quod propter idem acceperunt vacuum esse, propter quod acceperunt locum esse, scilicet propter motum, ut supra dictum est: quia provenit ut salvetur motus secundum locum, tam secundum illos qui dicunt locum aliquid esse praeter corpora quae sunt in loco, quam secundum illos qui ponunt vacuum esse. Negantibus autem locum et vacuum, non provenit motum secundum locum esse. Et sic vacuum quodammodo opinantur causam esse motus eo modo quo et locum, ut in quo scilicet est motus.	514. Then [355 214 a21] he shows why they posited a void. And he says that they admitted the existence of the void for the same reason that they admitted place, namely, on account of motion, as we said above: for it comes about that local motion is saved, both for those who assert that place is something over and above the bodies which are in place and for those who claim that the void exists. But for those who deny place and the void, there cannot be local motion. Consequently, some believed that the void is a cause of motion in the way that place is, i.e., as that in which motion takes place.
lib. 4 l. 10 n. 10 Deinde cum dicit: neque una autem necessitas est etc., excludit rationes ponentium vacuum esse. Et non intendit hic rationes praemissas vera solutione solvere; sed instantiam dare ex qua ex ipso aspectu apparet, quod rationes non ex necessitate concludunt. Primo ergo excludit rationes ponentium vacuum separatum; secundo ponentium vacuum in corporibus, ibi: contingit autem densari et cetera.	515. Then [356 214 a26] he rejects the arguments of those who posit existence of the void. He does not, however, intend here to give a true solution to the aforesaid arguments, but to bring an objection which at a glance shows that their arguments do not conclude with necessity. First therefore he rejects the reasons given by those who posit a separated void; Secondly, the arguments of those who posit a void existing in bodies, at no. 517.
lib. 4 l. 10 n. 11 Primam autem rationem excludit dupliciter. Primo quidem, quia non est necessarium si motus sit quod vacuum sit. Et si loquamur universaliter de qualibet specie motus, manifeste apparet quod nequaquam est necessarium. Nihil enim prohibet id quod est plenum, alterari: solus enim motus localis excludi videtur si vacuum non ponatur. Et hoc latuit Melissum, dum credidit remoto vacuo omnem speciem motus auferri. Secundo excludit eandem rationem per hoc quod neque motus localis tollitur, si vacuum non sit. Dato enim quod nullum spatium separabile sit praeter corpora quae moventur, potest motus localis esse per hoc quod corpora subintrent se invicem per modum inspissationis, et sic aliquid in plenum movetur, et non in vacuum. Et hoc apparet manifeste in generationibus corporum continuorum, et praecipue in humidis, sicut videtur in aqua. Si enim proiiciatur lapis in aliquam magnam latitudinem aquae, manifeste apparet fieri quasdam circulationes circa locum percussionis, quousque pars aquae depulsae commoveat aliam et subintret ipsam: unde quia modica pars aquae subintrat per quandam diffusionem in maiorem aquam, circulationes praedictae a parvo in maius procedunt, quousque totaliter deficiant.	516. He rejects the first reason in two ways: First, because even though motion exists, it does not necessarily follow that the void exists. And if we speak generally of any species of motion, it is clear that the void is not necessary at all. For nothing prevents the full from being altered [i.e., having motion in quality], since only local motion seems to be excluded if the void is not posited. Yet Melissus did not see this, for he believed that if there were no void, no motion of any kind could exist. Secondly, he rejects the same reason on the ground that not even local motion is destroyed, if there is no void. For, assuming that there is no separable space over and above moving bodies, local motion can take place, if bodies make room for one another by contracting: thus they would be moving into the full rather than into the empty. This is evident in the generations of continuous bodies, especially in liquids, such as water. For if a stone is thrown into a large surface of water, circles appear around the place of entry as long as one part of the moving water agitates another part and enters it. Hence, because a small portion of water by a process of diffusion enters a larger section, the circles grow from small to large until they cease entirely.
lib. 4 l. 10 n. 12 Deinde cum dicit: contingit autem densari etc., excludit rationes ponentium vacuum in corporibus. Et primo rationem quae procedebat ex condensatione. Et dicit quod contingit corpora condensari, et partes corporis subintrare sibi invicem, non propter hoc quod pars subintrans vadat in locum vacuum; sed ideo quia erant aliqua foramina, plena aliquo corpore subtiliori, quod facta condensatione elabitur: sicut quando aqua colliditur et inspissatur, aer qui intus erat, excluditur. Et haec maxime apparent in spongia, et in huiusmodi corporibus porosis. Haec igitur solutio non ostendit causam condensationis, quam inferius ponit: sed ostendit quod etiam per hunc modum manifeste excludi potest necessitas vacui.	517. Then [357 214 a32] he rejects the reasons given by those who posit a void in bodies. And first of all the reason based an condensation. And he says that bodies happen to become condensed, and parts of a body mutually penetrate, not because the invading part is entering an empty place but because there were certain openings, full of a more subtle body which escapes under condensation, just when water is compressed and contracted, the air that was present is expelled. This takes place manifestly in a sponge and other like porous bodies. Therefore this solution does not give the reason for condensation (he will give this later [L.14]: but it does show that also in this way, the need of a void can be clearly eliminated.
lib. 4 l. 10 n. 13 Secundo ibi: et augmentari etc., excludit rationem quae procedit ex augmento. Et dicit quod augmentum contingit esse non solum per additionem alicuius corporis ingredientis in corpus augmentatum, ut sic necesse sit esse vacuum, sed etiam per alterationem: sicut cum ex aqua fit aer, maior fit quantitas aeris quam erat aquae. Et haec etiam non est vera solutio rationis inductae: sed solum instantia quaedam, ne sit necesse ponere vacuum. Vera autem solutio ponitur in libro de generatione, ubi ostenditur quod alimentum non sic transit in id quod augetur, quasi sit aliud corpus ab ipso; sed quia convertitur in substantiam eius, sicut ligna apposita igni, convertuntur in ignem.	518. Secondly [358 214 b1] he rejects the argument based on growth. And he says that growth occurs not only by the addition of some body invading the growing body so as to make the void necessary but also by alteration, as, when air comes to be from water, the quantity of air becomes greater than the quantity of water. This too is not the true solution of their argument but merely an objection showing that it is not necessary to posit a void. The true solution is given in the book “De Generatione, where it is shown that food does not pass into that which grows as to be a body distinct from it; rather it is converted into its substance, as wood added to fire is converted into fire.
lib. 4 l. 10 n. 14 Tertio ibi: omnino autem et quae est de augmento etc., excludit simul et rationem de augmento et rationem de aqua effusa in cinerem: et dicit quod utraque ratio impedit seipsam. Quod sic patet. Est enim circa augmentum haec dubitatio. Videtur enim vel quod non totum augeatur; vel quod augmentum non fiat per additionem corporis, sed per additionem alicuius incorporei; aut quod contingat duo corpora esse in eodem loco. Hanc igitur dubitationem, quae communiter videtur esse tam contra ponentes vacuum, quam contra non ponentes, volunt solvere. Sed tamen non demonstrant quod vacuum sit; vel oportet eos dicere, si augmentum sit propter vacuum, quod totum corpus sit vacuum, cum totum corpus augeatur. Et similiter dicendum est de cinere: quia si vas plenum cinere recipit tantum de aqua quantum vacuum, oportet dicere quod totum sit vacuum. Non est igitur hoc propter vacuitatem: sed propter commixtionem in aqua. Aqua enim commixta cineri condensatur, et aliqua pars eius exhalat; et iterum partes cineris magis inspissantur humefactione: cuius signum est, quod non potest extrahi tantum de aqua, quantum prius fuit. Ultimo autem concludit quod manifestum est, quod facile est solvere ea ex quibus demonstrant vacuum esse.	519. Thirdly [359 214 b3] he rejects together both the argument about increase [in growth] and that about water poured on ashes and says that each of these arguments blocks the other. This is evident as follows. For there is in respect to increase this difficulty: it seems either that the whole body is not being increased, or that increase does not come about by the addition of body but by the addition of something incorporeal, or that two bodies can be in the same place. Now it is this difficulty, which seems to be against both these who posit a void and against those who do not, that they wish to solve. But they do not show that the void exists, or, if increase is due to the void, then they would have to say that the whole body is a void, since the whole body is increased. Likewise, in regard to the ashes: for if a vessel full of ashes can take as much water as the empty vessel, then one has to say that the whole container must be a void. Therefore this is not due to empty space but to being mixed in with the water. For when water is mixed with ashes it condenses and part of it evaporates; moreover, parts of the ash are condensed on account of the moisture, and a sign of this is that not as much water can be recovered as was put in. Finally, he concludes that it is clearly easy to solve the arguments by which they prove the existence of a void.