Authors/Thomas Aquinas/posteriorum/L2/Lect17

Lecture 17 How to investigate the why in special problems. How certain problems agree as to propter quid

Latin	English
	Lecture 17 (98a1-34) HOW TO INVESTIGATE THE WHY IN SPECIAL PROBLEMS. HOW CERTAIN PROBLEMS AGREE AS TO PROPTER QUID, EITHER BECAUSE THEIR MIDDLES HAVE A KIND OF UNITY OR ARE SUBORDINATED
lib. 2 l. 17 n. 1 Postquam ostendit philosophus quomodo oportet investigare quod quid est, hic ostendit quomodo oportet investigare propter quid. Et circa hoc duo facit: primo, ostendit quomodo oporteat investigari propter quid; secundo, movet quasdam quaestiones circa ipsum propter quid; ibi: de causa autem et cuius est causa et cetera. Circa primum duo facit: primo, ostendit quomodo alicuius quaestionis propositae possit investigari propter quid; secundo, ostendit quomodo diversae quaestiones communicant in propter quid; ibi: eadem autem problemata et cetera. Circa primum duo facit: primo, docet accipere propter quid, accipiendo commune univocum; secundo, accipiendo commune analogum; ibi: amplius autem alius modus et cetera.	After showing how one should go about investigating the quod quid, the Philosopher now shows how one should investigate propter quid. Concerning this he does two things. First, he shows how propter quid should be investigated. Secondly, how diverse questions make use of a common propter quid (98a23). Concerning the first he does two things. First, he shows that one takes the propter quid by taking some common univocal item. Secondly, by taking some common analogous item (9840).
Circa primum duo facit: primo, docet investigare propter quid, accipiendo commune univocum, quod est genus nominatum; secundo, accipiendo quodcunque aliud commune; ibi: nunc quidem igitur et cetera.	Concerning the first he does two things. First, he teaches how to take the propter quid by taking a common univocal item which is a definitively named genus. Secondly, by taking anything else that is common (98a13).
lib. 2 l. 17 n. 2 Dicit ergo primo quod ad hoc quod habeamus propter quid circa singula problemata quae ponuntur, oportet considerare divisiones et subdivisiones, et sic ad singula procedere disputando, supposito communi genere. Ut si aliquis velit considerare propter quid aliquid conveniat aliquibus animalibus, oportet accipere qualia sunt quae conveniunt omni animali. Quibus acceptis, oportet iterato accipere secundum divisionem qualia sunt quae consequuntur primo ad aliquod commune, quod sub animali continetur, puta qualia consequuntur ad omnem avem: et sic semper debemus procedere accipiendo illud quod est primum, in quod scilicet fit immediate divisio; quod etiam supra observabatur in divisionibus quibus proceditur ad investigandum quod quid est.	He says therefore first (98a1) that in order to get the propter quid in regard to individual problems that are proposed, it is required to consider divisions and subdivisions, and so to proceed to the individual cases by disputing, having first supposed a common genus. For example, if someone wished to consider why something belongs to certain types of animals, he would have to discover what items belong to every animal. Once these have been discovered, he would once more consult the divisions to determine what things follow first upon that common item which is contained under animal; for example, what things follow upon every bird. Then one would continue in this manner, always taking the first item into which a given division is immediately divided. This is the very thing that was observed above in the divisions by which one proceeds to investigate quod quid.
Sic autem procedendo manifestum est quod semper poterimus dicere propter quid aliqua insunt his quae continentur sub aliquo communi; ut si velimus scire propter quid aliqua insunt homini et equo, puta somnus et vigilia. Sit ergo animal in quo a, quod est medium; b autem, idest maior extremitas, accipiatur pro his quae inhaerent omni animali, sicut somnus et vigilia; quaedam autem animalium species, puta homo, equus, bos, accipiantur ut minor extremitas, scilicet cde. Sic igitur manifestum est propter quid b, idest somnus vel vigilia sit in d, puta in homine, quia propter a, idest propter hoc quod homo est animal. Et similiter est faciendum in aliis, et in omnibus est eadem ratio observanda. Huiusmodi autem documenti ratio est, quia subiectum est causa propriae passionis. Et ideo si volumus investigare causam alicuius passionis, propter quam insit quibusdam rebus inferioribus, oportet accipere commune quod est proprium subiectum, per cuius definitionem accipitur causa illius passionis.	By thus proceeding it is obvious that we shall always be able to say propter quid certain things are present in those things which are contained under something common. Thus, if we would like to know why certain things such as being asleep and being awake are found in man and horse, we would let animal be that in which A, the middle, is found, and let B, i.e., the major extreme, stand for items that inhere in every animal, say, being asleep and awake. Then we let certain species of animals, such as man, horse, cow, be taken as minor extremes, namely, C, D, E. In this way it is manifest that the reason why B, i.e., being asleep or awake, is found in D, i.e., in man, is that it is due to A, i.e., because man is an animal. Then the same should be done in regard to the others, and the same notion must be observed in all. The reason for this procedure is that the subject is the cause of a proper attribute. Therefore, if we wish to investigate the cause why some attribute is found in certain inferiors, it is necessary to take as common the proper subject through whose definition the cause of that attribute is taken.
lib. 2 l. 17 n. 3 Deinde cum dicit: nunc quidem igitur etc., ostendit quomodo oportet investigare propter quid est, reducendo in aliquod commune, quod non sit genus nominatum; et dicit quod ea quae supra dicta sunt, dicuntur secundum illa communia, quibus nomina sunt assignata; sed oportet non solum in talibus considerare, sed et si quid aliud appareat commune quod insit aliquibus, etiamsi non sit genus, vel si non sit nominatum. Deinde oportet considerare ad quae hoc commune consequatur, et quae sunt illa quae consequuntur ad hoc commune innominatum acceptum. Sicut habere cornua est quoddam commune, cui non est nomen impositum, et quod non est genus. Ad hoc autem commune sequuntur duo: quorum unum est, quod omne animal habens cornua habet multos ventres propter necessitatem ruminationis; quorum unus vocatur echinus, in interioribus existens, asper et capedines habens, ut dicitur in libro de historiis animalium. Aliud autem quod consequitur ad animalia habentia cornua, est quod non habeant dentes in utraque mandibula, sed solum in inferiori, quia materia dentium convertitur in cornua. Item considerandum est ad quae animalia consequatur habere cornua, puta bovem et cervum. Sic enim manifestum erit propter quid haec animalia habent illas proprietates, quia scilicet habent cornua.	Then (98a13) he shows how to investigate the propter quid by arriving at something common which is a genus without a definite name. And he says that what has been stated above applies to those common items to which names have been assigned. However, it is not enough to consider only such items but anything else which seems to be commonly present in them, even if it is not a genus or does not have a name. After that, one must discover what this common factor follows upon, as well as what follows upon this common unnamed factor. For example, to have horns is something common, but it neither has a name nor is it a genus. Furthermore, two things follow upon this common factor: one of these is that every horned animal, because it must chew its cud, has several stomachs; one of which, existing farther in and called echinus, is hard and prickly, as it is stated in The History of Animals II. Another item which follows upon horned animals is that they do not have teeth in both jaws, but only in the lower one, because the dental matter is converted into horns. Again one must consider which animals are apt to have horns, namely, cows and deers. For in that way it will be clear why these animals have those properties, namely, because they have horns.
lib. 2 l. 17 n. 4 Deinde cum dicit: amplius autem alius modus etc., ostendit investigare propter quid reducendo ad aliquod commune analogum; et dicit quod alius modus investigandi propter quid est eligere commune secundum analogiam, idest proportionem. Contingit enim unum accipere analogum, quod non est idem secundum speciem vel genus; sicut os sepiarum, quod vocatur sepion, et spina piscium, et ossa animalium terrestrium. Omnia enim ista conveniunt secundum proportionem, quia eodem modo se habent spinae ad pisces sicut ossa ad terrestria animalia. Ad hoc autem commune analogum quaedam consequuntur propter unitatem proportionis, sicut si communicarent in una natura generis vel speciei, sicut esse coopertum carnibus.	Then (98a20) he shows how to investigate propter quid by arriving at some common analogous item. And he says that another method of investigating propter quid is to select something common according to analogy, i.e., proportion. For it is possible to take something analogous which is not the same according to species or genus: for example, the bone (called sepion) of squid, the spine of fish and the backbone of land animals. For all these agree by proportion, because spine and backbone are related to fish and land animals in the same way. Now because of this unity of proportion certain things follow upon this common analogous item, just as if they shared in one generic or specific nature; for example, to be covered with flesh.
lib. 2 l. 17 n. 5 Deinde cum dicit: eadem autem problemata sunt etc., ostendit quomodo multa problemata conveniunt in eo quod est propter quid: et primo, quantum ad unitatem medii; secundo, quantum ad ordinem mediorum; ibi: alia autem et cetera. Dicit ergo primo quod quaedam problemata sunt eadem, in quantum scilicet conveniunt in eo quod est propter quid. Uno quidem modo propter hoc quod habent idem medium; sicut per hoc medium quod est antiperistasis, idest contra-resistentia vel repercussio, multa demonstrantur. Sunt autem quaedam media eadem non simpliciter, sed genere, quae quibusdam differentiis diversificantur, quae sumuntur vel ex diversitate subiectorum, vel ex diversitate modi fiendi. Sicut si quaeratur propter quid fit echo, aut propter quid apparet, scilicet aliquid in speculo, vel propter quid generatur iris. Omnia enim ista sunt idem problema quantum ad medium propter quid, quod est idem genere: omnia enim causantur ex repercussione. Sed repercussiones differunt specie. Nam echo fit per repercussionem aeris moti a corpore sonante ad aliquod corpus concavum; apparitio autem rei in speculo fit propter hoc quod immutatio medii repercutitur ad speculum; iris autem fit propter hoc quod radii solares repercutiuntur ad vapores humidos.	Then (98a23) he shows how many problems concur as to propter quid. First, as to having one middle. Secondly, as to the order of the middles (98a29). He says therefore first (98a23) that some problems are the same, namely, inasmuch as they agree as to propter quid. In one way, because they have the same middle: thus many things are demonstrated by the middle which is antiperistasis, i.e., counter-resistance or reverberation. On the other hand, some middles are the same not absolutely but in genus, and these are diversified by certain differences which are based either on the diversity of subjects or on the diversity of their ways of coming to be. For example, if it is asked why an echo comes to be, or why something appears, namely, in a mirror, or why a rainbow is formed. For they are the same problem as to the middle propter quid, which is generically the same, since all are caused by a reverberation. However, the reverberations differ specifically. For an echo comes to be through the reverberation of air set in motion by a sounding body toward a concave body; an image in a mirror comes to be by the fact that the modification of the medium is rebounded at the mirror; but the rainbow is formed by the rays of the sun being reflected back by moist vapors.
lib. 2 l. 17 n. 6 Deinde cum dicit: alia autem ex eo quod medium etc., ostendit quomodo problemata conveniunt in propter quid secundum ordinationem mediorum; et dicit quod quaedam alia problemata sunt, quae differunt ad invicem ex eo quod habent diversa media, quorum unum est sub altero. Et ponit exemplum, utpote si quaeratur propter quid Nilus in fine mensis, scilicet lunaris, magis inundat. Huius enim ratio est, quia finis mensis est magis pluvialis. Quare autem hoc sit, accipitur per aliud medium; propter hoc scilicet quod tunc deficit luna, quae habet dominium super humores, et ideo, deficiente lumine eius, magis commoventur vapores in aere, ex quo causatur pluvia. Et sic patet quod ista duo media sic se habent ad invicem, quod unum eorum est sub alio.	Then (98a29) he shows how problems agree as to propter quid by reason of the subordination of the middles. And he says that there are certain other problems which differ from one another in point of having diverse middles, one of which is under another. And he gives the example that someone wonders why the Nile overflows more near the end of the month, i.e., of the lunar month. For the reason is that there is more rain near the end of the month. And the reason for this is taken from another middle, namely, because the moon which controls moisture is waning then. Consequently, as its light wanes the vapors in the air condense more; and this causes rain. And so it is plain that those two middles are related to one another in the sense that one of them is under the other.