Authors/Thomas Aquinas/posteriorum/L2/Lect12

Lecture 12 How in things that come to be reciprocally, a cause which is not simultaneous with the effect is taken as middle in a demonstration

Latin	English
	Lecture 12 (95b38-96a20) HOW IN THINGS THAT COME TO BE RECIPROCALLY, A CAUSE WHICH IS NOT SIMULTANEOUS WITH THE EFFECT IS TAKEN AS MIDDLE IN A DEMONSTRATION HOW ONE DEMONSTRATES THROUGH CAUSE DIFFERENTLY, IN THINGS THAT OCCUR ALWAYS AND IN THINGS THAT OCCUR AS A GENERAL RULE
lib. 2 l. 12 n. 1 Postquam philosophus ostendit quomodo accipiendum sit medium quod est causa in his quae fiunt in rectum, hic ostendit quomodo debeat accipi in his quae fiunt secundum generationem circularem. Et primo, ostendit propositum; secundo, manifestat per exempla; ibi: in operibus autem videtur sic et cetera.	After showing how one must take the middle, which is the cause, in, things that come to be in a direct line, the Philosopher now shows hhow one should take it in the case of things that come to be in reciprocal generation. First, he proves his proposal. Secondly, he elucidates it with examples (96a2).
lib. 2 l. 12 n. 2 Circa primum considerandum est quod, quia motus caeli circularis causa est generationis in istis inferioribus, ideo dicitur in II de generatione, quod quaedam circulatio in generationibus invenitur, puta quod ex aqua generatur terra, et ex terra iterum aqua. Dicit ergo quod, quia videmus esse quamdam generationem in his quae circulo generantur, in his etiam contingit observari hoc quod supra dictum est, scilicet quod syllogizetur a posteriori, si hoc modo accipiantur termini demonstrationis, quod medium et extremi termini se invicem consequuntur: quia in his quae sic generantur, est quaedam conversio circularis, dum scilicet a primo generato devenitur ad ultimum, et ab ultimo reditur ad primum, non idem numero, sed idem specie, ut patet in II de generatione. Et ita non sequitur quod idem numero sit prius et posterius, effectus et causa.	In regard to the first it should be noted that because the circular movement of the heavens is the cause of generation in sublunar things, it is stated in On Generation II that a kind of circular reciprocity is found is generation in the sense that earth is generated from water, and water in turn from earth. He says therefore (95b38) that since we observe a certain pattern of generation in things that are generated circularly, it is possible in these cases also to follow what has been established above, namely, to syllogize from what is subsequent, provided that the terms of the demonstration are taken in such a way that middle and extremes follow one upon the other: because in the case of things that are generated in that way, there is a kind of circular conversion in the sense that one passes from the first thing to the last thing, and then a return is made from the last to the first; although these things are not numerically but specifically the same, as is explained in On Generation II. Hence it does not follow that the same numerical thing is prior and subsequent, or is cause and effect.
Et hoc ipsum competit processui demonstrationum, eo quod, ut in praecedentibus dictum est, quandoque conclusiones convertuntur, ut scilicet ex eis syllogizentur aliquae praemissarum; hoc enim est circulo demonstrare. Quod quamvis non competat si omnino sit unum et idem quod prius fuit conclusio, et postea est principium respectu eiusdem numero, ne sit idem notius et minus notum; si tamen non sit omnino idem, sicut accidit in his quae circulo generantur, nullum inconveniens est.	And this is suitable to the process of demonstrations, for, as has been established in the foregoing, whenever conclusions are converted, i.e., whenever some of the premises can be syllogized from them, this is a circular demonstration. And although this is not fitting if the very same thing which was first the conclusion is later the principle of the same numerical thing (otherwise the same thing would be at once better known and less known), nevertheless if they are not entirely the same, as happens in things that are circularly generated, there is nothing unfitting.
lib. 2 l. 12 n. 3 Deinde cum dicit: in operibus autem videtur sic etc., manifestat quod dixerat per exempla, et dicit quod in ipsis operibus naturae videtur sic evenire, quod sit quidam circularis processus. Quia si terra sit compluta, necesse est quod per actionem solis vapor ex ea resolvatur; quo resoluto et sursum elevato, necesse est quod generetur nubes; et hac generata, necesse est quod generetur aqua pluviae; qua generata, necesse est quod cadens super terram compluat eam. Et hoc est quod accipiebamus quasi primum: non tamen est eadem complutio terrae ad quam ultimo pervenitur, et a qua primo incipiebatur.	Then (96a2) he uses examples to elucidate what he has said, saying that a circular process is seen to occur in the works of nature. For if the earth is saturated with rain, it is necessary that the action of the sun release vapors from it; when these are released and borne aloft, it is necessary that clouds be formed; and after they are formed, it is necessary that rainwater be formed; and when this is formed, it is necessary that in falling upon the earth it saturate it. Now this saturation of the earth was the very thing we took as being first; however, it is not the same saturation as the one from which we first began.
Et sic manifestum est quod factus est quidam circuitus, inquantum uno eorum existente fit aliud, et illo existente fit aliquod aliud; quo existente reditur ad primum, non idem numero, sed idem specie. Iste tamen causarum circuitus inveniri non potest secundum ordinem qui invenitur in causis per se: sic enim necesse est pervenire ad unum primum in quolibet genere causarum, ut probatur in II Metaphys. Quod autem aqua generetur ex igne, et ignis iterato ex aqua, hoc non est per se, sed per accidens. Non enim ens per se generatur ut ex ente in actu, sed ex ente in potentia, ut dicitur in I Physicor. Procedendo ergo in causis per se non erit circulatio. Nam complutionis terrae causam agentem accipiemus calorem aeris, qui causatur ex sole, et non e converso; causam vero materialem aquam, cuius materia non est vapor, sed materia communis elementorum.	Thus it is clear that a cycle has been achieved in the sense that with one of them existing, another comes to be; and that other existing, still another comes to be; and that one existing, a return is made to the first, which is not numerically the same, but specifically the same. Yet this cycle of causes cannot be found according to the order which is found in pe se causes; for in per se causes it is necessary to reach some one thing which is first in each genus of causes as is proved in Metaphysics II. But the fact that water is generated from fire, and fire in turn from water, is not per se but per accidens. For being is generated per se not from actual being but from potential being, as it is stated in Physics I. Therefore, if we proceed from cause to cause in per se causes, there will not be a cycle. For we will accept as the efficient cause of the rain-soaked earth, the heat of the air which is caused by the sun, but not vice versa; but the material cause we take as water, whose matter is not vapor but the common matter of the elements.
lib. 2 l. 12 n. 4 Deinde cum dicit: sunt autem quaedam quae etc., ostendit qualiter diversimode demonstretur per causam in his quae sunt semper, et in his quae sunt ut frequenter. Et circa hoc tria facit: primo, proponit quod intendit; secundo, probat propositum; ibi: si enim a de b etc., tertio, epilogat quae dicta sunt; ibi: quomodo quidem igitur et cetera. Dicit ergo primo quod quaedam sunt quae universaliter fiunt, et quantum ad tempus, quia semper, et quantum ad subiectum, quia in omnibus, aut se habent, sicut immobilia, quibus non competit proprie fieri, aut fiunt, sicut mobilia quae semper eodem modo se habent, ut patet in motibus caelestibus. Quaedam vero non fiunt sicut semper, sed sicut frequenter. Et ponit de his exemplum. Sicut quod omnis homo masculus efficiatur quandoque barbatus, non accidit semper, sed sicut frequenter. Sicut igitur eorum quae sunt semper, oportet accipere medium quod est semper; ita et talium, quae sunt sicut frequenter, oportet accipere medium sicut frequenter.	Then (96a8) he shows how one demonstrates through the cause differently in things which occur always and in things which occur as a general rule. Concerning this he does three things. First, he proposes what he intends. Secondly, he proves what he has proposed (96a12). Thirdly, he sums up (96a20). He says therefore first (96a8) that there are some things which come to be universally both as to time, because always, and as to subject, because in all cases; either because they maintain themselves as unchangeable things which are not subject to coming to be, or because they come to be as changeable things which always follow a uniform pattern, as in the case of heavenly movements. Again, there are other things which do not occur in the sense of always, but as a general rule. An example of this is that every human male develops a beard as a general rule, although it does not occur always. Therefore, just as in the case of things that occur always, it is necessary to take a middle which is always, so in the case of things which occur as a general rule, it is necessary to take a middle that occurs as a general rule.
lib. 2 l. 12 n. 5 Deinde cum dicit: si enim a de b praedicatur etc., probat quod ad concludendum id quod est sicut frequenter, necesse sit accipere medium quod sit sicut frequenter. Detur enim oppositum, quod accipiatur medium quod sit universaliter et semper; puta si a, quae est maior extremitas, praedicetur universaliter de b, quod est medium, et b de c, quod est minor extremitas: ex necessitate sequitur quod a praedicetur de c universaliter, et quantum ad tempus et quantum ad subiectum, quod est semper et de omni praedicari. Unde idem nunc dicimus universaliter praedicari, quod praedicari de omni et semper.	Then (96a12) he proves that if one is to conclude to something that occurs as a general rule it is necessary to take a middle which occurs as a general rule. For if one were to assume the opposite by taking a middle which occurs universally and always; for example, if A, which is the major extreme, is predicated universally of B, which is the middle, and B of C, which is the minor extreme, then it follows of necessity that A is predicated universally of C both as to time and as to subject, which is the same as being predicated always and of each thing. Hence, we are now saying that for something to be predicated universally is the same as being predicated of all and always.
Sed suppositum erat quod a praedicaretur de c sicut frequenter. Necesse est ergo quod medium, quod est b, accipiatur sicut frequenter existens. Sic igitur patet quod possunt accipi quaedam immediata principia eorum quae sunt frequenter, ita quod ipsa principia sint aut fiant sicut frequenter. Huiusmodi tamen demonstrationes non faciunt simpliciter scire verum esse quod concluditur, sed secundum quid, scilicet quod sit verum ut in pluribus; et sic etiam principia quae assumuntur, veritatem habent. Unde huiusmodi scientiae deficiunt a scientiis, quae sunt de necessariis absolute, quantum ad certitudinem demonstrationis.	But it has been assumed that A is predicated of C as a general rule. Therefore, it is necessary that the middle, which is B, should be taken as existing as a general rule.Thus it is obvious that certain immediate principles of things which occur as a general rule can be taken, such that those principles exist or come to be as a general rule. Yet such demonstrations do not enable one to know that what is concluded is true absolutely but only in a qualified sense, namely, that it is true in the majority of cases. And this is the way that the principles which are taken possess truth. Hence sciences of this kind fall short of sciences which deal with things absolutely necessary, so far as the certitude of demonstration is concerned.
lib. 2 l. 12 n. 6 Deinde cum dicit: quomodo quidem igitur etc., epilogat ea quae dicta sunt; et dicit quod iam supra dictum est, quomodo quod quid est, quod est aliqualiter idem ei quod propter quid, assignatur inter terminos syllogisticos, dum ostensum est qualiter singula causarum genera, et in singulis diversitatibus rerum, sint media demonstrationum. Dictum est etiam qualiter eius quod quid est sit vel non sit demonstratio vel definitio.	Then (96a20) he sums up what has been said, saying that we have now established how the quod quid which is practically identical with the propter quid is assigned among syllogistic terms, inasmuch as we have shown how the several genera of causes are middles of demonstration according to the respective diversities of things. We have also shown in what sense there is or is not demonstration or definition of the quod quid.

Notes

Latin	English
	English translation by Fabian R. Larcher