Authors/Thomas Aquinas/physics/L4/lect8

Lecture 8 The definition of place is used to solve the original problems; the properties of place are justified

Latin	English
	Lecture 8 The definition of place is used to solve the original problems; the properties of place are justified.
lib. 4 l. 8 n. 1 Postquam philosophus ostendit quid sit locus, hic ex definitione data solvit dubitationes supra positas de loco. Fuerunt autem supra positae sex rationes ad ostendendum locum non esse; quarum duas praetermittit, illam scilicet in qua inquirebatur utrum locus esset elementum vel ex elementis, et iterum illam in qua ostendebatur quod ad nullum genus causae locus reducatur: non enim a ponentibus locum, sic ponitur quasi elementum vel causa rerum. Unde facit mentionem solum de quatuor residuis.	487. After explaining what place is, the Philosopher now uses his definition to resolve the doubts that were raised about place (L.2). Now there were mentioned above six reasons to show that place does not exist. Of these he bypasses two: the one in which it was asked whether place be an element or a composite of elements; the other in which it was shown that place cannot be reduced to any genus of cause. He bypasses them because no one who posited place took it either as an element or as a cause of things. Hence he makes mention only of the four remaining.
lib. 4 l. 8 n. 2 Quarum una erat, quod cum locus non deesset corpori nec corpus loco, videbatur sequi quod augmentato corpore, augmentetur locus. Sed hoc sequitur si supponatur quod locus sit spatium quoddam coextensum dimensionibus corporis, ut intelligatur illud spatium crescere, crescente corpore. Sed hoc non est necesse secundum definitionem praedictam de loco, quod sit terminus continentis.	488. One of these was that, since place never lacks a body, and a body never lacks a place, it seemed to follow that if the body grew, the place would grow. Now this would follow if it were supposed that place were a space co-extensive with the dimensions of the body, so that, as the body increased, so would the space. But this does not follow from the aforesaid definition of place, namely, that it is the boundary of the container.
lib. 4 l. 8 n. 3 Alia ratio fuit, quod si locus corporis est aliud a corpore, quod etiam locus puncti sit aliud a puncto: quare non videbatur possibile quod locus sit aliud a corpore, cum locus puncti non sit aliud a puncto. Sed haec etiam ratio procedit secundum imaginationem eorum qui opinabantur locum esse spatium coaequatum dimensionibus corporis: unde oportebat quod cuilibet dimensioni corporis responderet dimensio spatii, et similiter cuilibet puncto corporis. Sed hoc non oportet dicere, si ponamus locum esse terminum continentis.	469. Another argument was that, if the place of a body be distinct from the body, then the place of a point would be distinct from the point; wherefore, it did not seem possible for place to be distinct from the body, since the place of a point is not distinct from the point. But this argument was based on the imagining of those who opined, that place, is the space coextensive with the volume of the body, so that a dimension of space would correspond to a dimension of the body and in like manner to each point of the body, This, however, need not be said if we suppose that place is the boundary of the container.
lib. 4 l. 8 n. 4 Alia ratio fuit, quod si locus est aliquid, oportet quod sit corpus, cum habeat tres dimensiones; et sic sequetur duo corpora esse in eodem loco. Sed secundum eos qui ponunt locum esse terminum corporis continentis, non oportet dicere, neque quod duo corpora sint in eodem loco, neque quod sit aliquod spatium corporeum medium inter extremitates corporis continentis: sed quod sit ibi quoddam corpus.	490. Another argument was that, if place is anything, it must be a body, since it has three dimensions. Consequently, there would be two bodies in the same place. But according to those who agree that place is the boundary of the containing body it is not necessary to say that two bodies would be in the same place, or that there is some bodily space intervening between the boundaries of the containing body, but that there is some body there.
lib. 4 l. 8 n. 5 Item alia ratio fuit, quod si omne quod est, est in loco, sequetur quod etiam locus sit in loco. Quae quidem ratio de facili solvitur, supposito quod locus sit terminus continentis. Manifestum est enim secundum hoc, quod locus est in aliquo, scilicet in corpore continente; non tamen sicut in loco, sed sicut terminus in aliqua re finita, ut punctum in linea et superficies in corpore. Non enim necessarium est quod omne quod est, sit in aliquo sicut in loco; sed hoc necesse est solum de corpore mobili: motus enim induxit ad distinguendum inter locatum et locum.	491. Likewise another argument was that, if everything that exists is in place, it will follow that even a place is in place. This argument is easy to answer, if we suppose that place is the boundary of the container, For according to this it is clear that place is in something; namely, in the containing body, but it is there, not as in a place, but as a boundary in a finite thing, just as a point is in a line and a surface in a body. For it is not required that everything that is, be in something as in a place; this is required only of a mobile body, for it is motion that led to distinguishing between the thing in place and the place itself.
lib. 4 l. 8 n. 6 Deinde cum dicit: et fertur igitur in sui etc., assignat ex praedicta definitione rationem proprietatum loci. Et primo quantum ad hoc, quod corpus naturaliter fertur ad proprium locum; secundo quantum ad hoc, quod corpus naturaliter quiescit in suo loco, ibi: et manet igitur natura et cetera. Dicit ergo primo, quod si ponatur locus esse terminus continentis, rationabiliter assignari potest causa, quare unumquodque corpus feratur ad proprium locum: quia illud corpus continens, ad quod consequenter se habet corpus contentum et locatum, et quod ab eo tangitur terminis simul existentibus, et hoc non per violentiam, est proximum ei secundum naturam. Ordo enim situs in partibus universi attenditur secundum ordinem naturae. Nam corpus caeleste, quod est supremum, est nobilissimum: post quod inter alia corpora secundum nobilitatem naturae est ignis; et sic deinceps usque ad terram. Unde manifestum est quod corpus inferius, quod se habet consequenter secundum situm ad corpus superius, est proximum sibi in ordine naturae. Et ideo addit non vi, ut ostendat naturalem ordinem situs, cui respondet ordo naturarum, et excludat ordinem situs violentum, sicut aliquando per violentiam corpus terrestre est super aerem vel aquam. Et huiusmodi duo corpora se consequentia in naturali ordine situs, et in ordine naturarum simul apta nata esse, sunt impassibilia: idest, cum continuantur ad invicem et fiunt unum, ad quod aptitudinem habent propter propinquitatem naturae, tunc sunt impassibilia. Sed dum tanguntur distincta existentia, propter contrarietatem qualitatum activarum et passivarum, sunt activa et passiva ad invicem. Sic igitur proximitas naturae, quae est inter corpus continens et contentum, est causa quare corpus naturaliter movetur ad suum locum: quia oportet quod gradus naturalium locorum respondeat gradui naturarum, ut dictum est. Sed haec ratio non potest assignari si ponatur locus esse spatium: quia in dimensionibus spatii separatis nullus ordo naturae considerari potest.	492. Then [338 212 b29] he uses his definition to give a reason for the properties of place. First, as to the fact that a body is naturally borne to its proper place; Secondly, as to the fact that a body naturally rests in its own place, at no. 493. He says first therefore, that if place be taken to the boundary of the container, the reason why each body is naturally borne to its own place can be given: it is because the containing body (which is next to the contained and located body, and which is touched by it so that the boundaries of both are together not by compulsion) is akin to it in nature. For the order of situs in the parts of the universe follows upon the order of nature. For the heavenly body, which is supreme, is the most noble; after it, among the other bodies the noblest in nature is fire, and so on down to earth. Hence it is clear that the lower body which is situated according to position, next to the higher body, is akin to it in the order of nature. And therefore he adds, “not by compulsion,” in order to point out the natural order of situs to which the order of nature corresponds and to exclude a compulsive order of situs, as when by compulsion a body of earth is above air or water. Two such bodies next to one another in the natural order of situs and which, in the natural order of natures, are disposed to be together, do not affect each other; i.e., when they are made continuous to each other and become one—and for this they have an aptitude on account of the similarity of their natures—then they do not interact. But when distinct things are in contact, their mutually interact on account of the contrariety of their active and passive qualities. Therefore it is the kinship of nature existing between the container and the thing contained that explains why a body is naturally moved to its own place: because the rank in natural places must correspond to the rank in natures, as was said. But such a reason cannot be assigned if place is taken to be space: because in the separated dimensions of space no order of nature can be considered.
lib. 4 l. 8 n. 7 Deinde cum dicit: et manet igitur natura etc., assignat causam quare corpora naturaliter quiescant in suis locis. Et dicit quod hoc accidit rationabiliter, si ponamus locum esse terminum corporis continentis: quia secundum hoc corpus locatum se habet ad corpus continens sicut quaedam pars ad totum, divisa tamen. Et hoc manifestius apparet in corporibus quae sunt facilis divisionis, sicut est aer vel aqua: horum enim partes possunt moveri ab aliquo in toto, sicut locatum movetur in loco. Et hoc etiam non solum verum est secundum figuram continendi unum sub alio, sed etiam secundum proprietatem naturae. Aer enim se habet ad aquam ut totum, quia aqua est ut materia, aer autem ut forma; nam aqua est quasi materia aeris, et aer est sicut forma eius. Quod ex hoc apparet, quia aqua est in potentia ad aerem simpliciter. Sed verum est quod etiam aer est quodam alio modo in potentia ad aquam, ut determinabitur posterius in libro de generatione: sed ad praesens tempus necesse est hoc accipere ad ostensionem propositi. Sed hic non declaratur per certitudinem, sed in libro de generatione declarabitur certius. Ibi enim dicetur quod cum ex aqua generatur aer, est corruptio secundum quid, et generatio simpliciter, propter hoc quod perfectior forma introducitur, et imperfectior abiicitur. Cum autem ex aere generatur aqua, est corruptio simpliciter et generatio secundum quid, quia perfectior forma abiicitur, et imperfectior introducitur. Sic igitur aqua simpliciter est in potentia ad aerem, sicut imperfectum ad perfectum: aer autem est in potentia ad aquam, sicut perfectum ad imperfectum. Unde aer se habet ut forma et ut totum, quod habet rationem formae: aqua vero se habet ut materia et ut pars, quae pertinet ad rationem materiae. Quamvis igitur idem sit et materia et actus, quia aqua in se continet utrumque; sed tamen hoc quidem est in potentia proprie loquendo, scilicet aqua, sicut imperfectum: illud vero, scilicet aer, in actu ut perfectum. Unde habebit se aqua ad aerem quodammodo sicut pars ad totum. Et ideo his, scilicet aeri et aquae, cum sint duo distincta, inest tactus: sed cum ex utrisque fit unum, uno transeunte in naturam alterius, tunc fit copulatio, idest continuatio. Sicut igitur pars naturaliter quiescit in toto, ita et naturaliter corpus quiescit in suo loco naturali. Considerandum tamen est quod philosophus hic loquitur de corporibus secundum formas substantiales, quas habent ex influentia corporis caelestis, quod est primus locus, et dans virtutem locativam omnibus aliis corporibus: secundum autem qualitates activas et passivas est contrarietas inter elementa, et unum est corruptivum alterius. Ultimo autem epilogando concludit, quod dictum est de loco et quod est et quid est.	493. Then [339 212 b33] he gives the reason why bodies naturally rest in their own place. And he says that this happens reasonably, if we grant that place is the boundary of the containing body: because according to this the contained body is related to the containing body after the manner of a part to a whole—a separated part, however. This is abundantly clear in bodies that are easy to divide, such as air or water: for their parts can be moved by something in the whole just as a thing in place is moved in a place. And this also is not only true according to the figure of containing one under the other, but even according to the properties of their nature. For air is related to water as the whole, because water is like matter and air like the form: water is as the matter of air, and air is as the form of water. This is so because water is in potency to air absolutely. Now while it is true that in some other ways air is in potency to water, as will be explained later in De Generatione, it is necessary for the present to accept this in order that we may explain our proposition. Here it is not declared as a certainty, but in the De Generatione it will be proved with greater certainty. For it will be said there that, when air is generated from water, it is corruption secundum quid and generation simply, because a more perfect form is being introduced and a less perfect one is being put off. But when water is generated from air, it is corruption simply and generation secundum quid, because. a more perfect form is being put off and an imperfect one being introduced. Consequently, water is in potency to air absolutely as the imperfect to the perfect; but air is in potency in water as the perfect to the imperfect. Hence air is as the form, and as the whole which is like the form; water, however, is as the matter and as a part, which pertains to the notion of matter. Therefore, although the same thing is both matter and act, because the water contains both in itself; yet properly speaking, the latter, i.e., the water, is in potency as an imperfect thing, but the former, i.e., the air, in act as a perfect. Hence water will be related to air somewhat as part to whole. And therefore these things, the air and the water, when they are distinct things, they are in contact; but when they form a unity, by one passing into the nature of the other, then coupling, i.e., continuity occurs. Therefore, just as the part naturally is at rest in the whole, so also a body naturally rests in its natural place. Note, however, that the Philosopher is speaking here of bodies according to the substantial forms which they have under the influence of the heavenly body which is the first place, and which gives to all other bodies the power to act as places. But if we consider active and passive qualities, there is contrariety among the elements and one tends to destroy another. Finally he concludes in summary that it has been stated that place exists and what place is.