Authors/Thomas Aquinas/metaphysics/liber4/lect6

Lecture 6

Latin	English
lib. 4 l. 6 n. 1 Hic ostendit principaliter, quod ad primum philosophum pertinet considerare de primo demonstrationis principio: et circa hoc duo facit. Primo ostendit, quod eius est de ipso considerare. Secundo de ipso tractare incipit, ibi, principium vero et cetera. Circa primum tria facit. Primo ostendit, quod huius scientiae est considerare de primo demonstrationis principio. Secundo ostendit quid sit illud, ibi, et firmissimum et cetera. Tertio excludit quosdam errores circa idem principium, ibi, sunt autem quidam et cetera. Utitur autem ad primum tali ratione. In unoquoque genere ille est maxime cognoscitivus, qui certissima cognoscit principia; quia certitudo cognitionis ex certitudine principiorum dependet. Sed primus philosophus est maxime cognoscitivus et certissimus in sua cognitione: haec enim erat una de conditionibus sapientis, ut in prooemio huius libri patuit, scilicet quod esset certissimus cognitor causarum; ergo philosophus debet considerare certissima et firmissima principia circa entia, de quibus ipse considerat sicut de genere sibi proprie subiecto.	596. He shows here that it is the first philosopher who is chiefly concerned with the first principle of demonstration; and in regard to this he does two things. First, he shows that it is the business of the first philosopher to consider this principle; and second (611), he begins to examine this principle. In regard to the first he does three things.. First, he shows that it is the office of this science to consider the first principle of demonstration. Second (597), he indicates what this principle is. Third (606), he rejects certain errors regarding this same principle. In regard to the first point he uses the following argument. In every class of things that man is best informed who knows the most certain principles, because the certitude of knowing depends on the certitude of principles. But the first philosopher is best informed and most certain in his knowledge; for this was one of the conditions of wisdom, as was made clear in the prologue of this work (35), namely, that he who knows the causes of things has the most certain knowledge. Hence the philosopher ought to consider the most certain and firmest principles of beings, which he considers as the subject-genus proper to himself.
lib. 4 l. 6 n. 2 Deinde cum dicit et firmissimum hic ostendit quid sit firmissimum sive certissimum principium: et circa hoc duo facit. Primo dicit quae sunt conditiones certissimi principii. Deinde adaptat eas uni principio, ibi, quid vero sit et cetera. Ponit ergo primo, tres conditiones firmissimi principii. Prima est, quod circa hoc non possit aliquis mentiri, sive errare. Et hoc patet, quia cum homines non decipiuntur nisi circa ea quae ignorant: ideo circa quod non potest aliquis decipi, oportet esse notissimum.	597. And the firmest (327). Then he shows what the firmest or most certain principle is; and in regard to this he does two things. First, he states the conditions for the most certain principle; and then (600) he shows how they fit a single principle (“And let us”). He accordingly gives, first, the three conditions for the firmest principle. (1) The first is that no one can make a mistake or be in error regarding it. And this is evident because, since men make mistakes only about those things which they do not know, then that principle about which no one can be mistaken must be the one which is best known.
lib. 4 l. 6 n. 3 Secunda conditio est ut sit non conditionale, idest non propter suppositionem habitum, sicut illa, quae ex quodam condicto ponuntur. Unde alia translatio habet. Et non subiiciantur, idest non subiiciantur ea, quae sunt certissima principia. Et hoc ideo, quia illud, quod necessarium est habere intelligentem quaecumque entium hoc non est conditionale, idest non est suppositum, sed oportet per se esse notum. Et hoc ideo, quia ex quo ipsum est necessarium ad intelligendum quodcumque, oportet quod quilibet qui alia est cognoscens, ipsum cognoscat.	598. (2) The second condition is that it must “not be hypothetical,” i.e., it must not be held as a supposition, as those things which are maintained through some kind of common agreement. Hence another translation reads “And they should not hold a subordinate place,” i.e., those principles which are most certain should not be made dependent on anything else. And this is true, because whatever is necessary for understanding anything at all about being “is not hypothetical,” i.e., it is not a supposition but must be self-evident. And this is true because whatever is necessary for understanding anything at all must be known by anyone who knows other things.
lib. 4 l. 6 n. 4 Tertia conditio est, ut non acquiratur per demonstrationem, vel alio simili modo; sed adveniat quasi per naturam habenti ipsum, quasi ut naturaliter cognoscatur, et non per acquisitionem. Ex ipso enim lumine naturali intellectus agentis prima principia fiunt cognita, nec acquiruntur per ratiocinationes, sed solum per hoc quod eorum termini innotescunt. Quod quidem fit per hoc, quod a sensibilibus accipitur memoria et a memoria experimentorum et ab experimento illorum terminorum cognitio, quibus cognitis cognoscuntur huiusmodi propositiones communes, quae sunt artium et scientiarum principia. Manifestum est ergo quod certissimum principium sive firmissimum, tale debet esse, ut circa id non possit errari, et quod non sit suppositum et quod adveniat naturaliter.	599. (3) The third condition is that it is not acquired (~) by demonstration or by any similar method, but (+) it comes in a sense by nature to the one having it inasmuch as it is naturally known and not acquired. For first principles become known through the natural light of the agent intellect, and they are not acquired by any process of reasoning but by having their terms become known. This comes about by reason of the fact that memory is derived from sensible things, experience from memory, and knowledge of those terms from experience. And when they are known, common propositions of this kind, which are the principles of the arts and sciences, become known. Hence it is evident that the most certain or firmest principle should be such that there can be no error regarding it; that it is not hypothetical; and that it comes naturally to the one having it.
lib. 4 l. 6 n. 5 Deinde cum dicit quid vero ostendit cui principio praedicta determinatio conveniat: et dicit, quod huic principio convenit tamquam firmissimo, quod est impossibile eidem simul inesse et non inesse idem: sed addendum est, et secundum idem: et etiam alia sunt determinanda circa hoc principium, quaecumque determinari contingit ad logicas difficultates, sine quibus videtur contradictio cum non sit.	600. And let us next (328). Then he indicates the principle to which the above definition applies. He says that it applies to this principle, as the one which is firmest: it is impossible for the same attribute both to belong and not belong to the same subject at the same time. And it is necessary to add “in the same respect”; and any other qualifications that have to be given regarding this principle “to meet dialectical difficulties” must be laid down, since without these qualifications there would seem to be a contradiction when there is none.
lib. 4 l. 6 n. 6 Quod autem praedicta huic principio conveniant, sic ostendit. Impossibile enim est quemcumque suscipere, sive opinari, quod idem sit simul et non sit: quamvis quidam arbitrentur Heraclitum hoc opinatum fuisse. Verum est autem, quod Heraclitus hoc dixit, non tamen hoc potuit opinari. Non enim necessarium est, quod quicquid aliquis dicit, haec mente suscipiat vel opinetur.	601. That this principle must meet the conditions given above he shows as follows: (1) It is impossible for anyone to think, or hold as an opinion, that the same thing both is and is not at the same time, although some believe that Heraclitus was of this opinion. But while it is true that Heraclitus spoke in this way, he could not think that this is true; for it is not necessary that everything that a person says he should mentally an opinion.
lib. 4 l. 6 n. 7 Si autem aliquis diceret, quod contingeret aliquem opinari idem simul esse et non esse, sequitur hoc inconveniens, quod contingit contraria eidem simul inesse. Et haec determinentur nobis, idest ostendantur quadam propositione consueta et in logicis determinata. Ostensum est enim in fine perihermenias, quod opiniones sunt contrariae, non quae sunt contrariorum, sed quae sunt contradictionis per se loquendo. Hae enim non sunt contrariae opiniones primo et per se, ut si unus opinetur, quod Socrates est albus, et alius opinetur quod Socrates est niger. Sed, quod unus opinetur quod Socrates est albus, et alius opinetur quod Socrates non est albus.	602. But if one were to say that it is possible for someone to think that the same thing both is and is not at the same time, this absurd consequence follows: contraries could belong to the same subject at the same time. And “let us suppose that the same things are established,” or shown, here as in the usual proposition established in our logical treatises. For it was shown at the end of the Peri hermineas I that contrary opinions are not those which have to do with contraries but those which have to do with contradictories, properly speaking. For when one person thinks that Socrates is white and another thinks that he is black, these are not contrary opinions in the primary and proper sense; but contrary opinions are had when one person thinks that Socrates is white and another thinks that he is not white.
lib. 4 l. 6 n. 8 Si igitur quis opinetur simul duo contradictoria esse vera, opinando simul idem esse et non esse, habebit simul contrarias opiniones: et ita contraria simul inerunt eidem, quod est impossibile. Non igitur contingit aliquem circa haec interius mentiri et quod opinetur simul idem esse et non esse. Et propter hoc omnes demonstrationes reducunt suas propositiones in hanc propositionem, sicut in ultimam opinionem omnibus communem: ipsa enim est naturaliter principium et dignitas omnium dignitatum.	603. Therefore, if someone were to think that two contradictories are true at the same time by thinking that the same thing both is and is not at the same time, he will have contrary opinions at the same time; and thus contraries will belong to the same thing at the same time. But this is impossible. It is impossible, then, for anyone to be mistaken in his own mind about these things and to think that the same thing both is and is not at the same time. And it is for this reason that all demonstrations reduce their propositions to this proposition as the ultimate opinion common to all; for this proposition is by nature the starting point and axiom of all axioms.
lib. 4 l. 6 n. 9 Et sic patent aliae duae conditiones; quia inquantum in hanc reducunt demonstrantes omnia, sicut in ultimum resolvendo, patet quod non habetur ex suppositione. Inquantum vero est naturaliter principium, sic patet quod advenit habenti, et non habetur per acquisitionem.	604. (2 & 3) The other two conditions are therefore evident, because, insofar as those making demonstrations reduce all their arguments to this principle as the ultimate one by referring them to it, evidently this principle is not based on an assumption. Indeed, insofar as it is by nature a starting point, it clearly comes unsought to the one having it and is not acquired by his own efforts.
lib. 4 l. 6 n. 10 Ad huius autem evidentiam sciendum est, quod, cum duplex sit operatio intellectus: una, qua cognoscit quod quid est, quae vocatur indivisibilium intelligentia: alia, qua componit et dividit: in utroque est aliquod primum: in prima quidem operatione est aliquod primum, quod cadit in conceptione intellectus, scilicet hoc quod dico ens; nec aliquid hac operatione potest mente concipi, nisi intelligatur ens. Et quia hoc principium, impossibile est esse et non esse simul, dependet ex intellectu entis, sicut hoc principium, omne totum est maius sua parte, ex intellectu totius et partis: ideo hoc etiam principium est naturaliter primum in secunda operatione intellectus, scilicet componentis et dividentis. Nec aliquis potest secundum hanc operationem intellectus aliquid intelligere, nisi hoc principio intellecto. Sicut enim totum et partes non intelliguntur nisi intellecto ente, ita nec hoc principium omne totum est maius sua parte, nisi intellecto praedicto principio firmissimo.	605. Now for the purpose of making this evident it must be noted that, since the intellect has two operations, one by which it knows quiddities, which is called the understanding of indivisibles, and another by which it combines and separates, there is something first in both operations. In the first operation the first thing that the intellect conceives is being, and in this operation nothing else can be conceived unless being is understood. And because this principle—it is impossible for a thing both to be and not be at the same time—depends on the understanding of being (just as the principle, every whole is greater than one of its parts, depends on the understanding of whole and part), then this principle is by nature also the first in the second operation of the intellect, i.e., in the act of combining and separating. And no one can understand anything by this intellectual operation unless this principle is understood. For just as a whole and its parts are understood only by understanding being, in a similar way the principle that every whole is greater than one of its parts is understood only if the firmest principle is understood.
lib. 4 l. 6 n. 11 Deinde cum dicit sunt autem ostendit quomodo circa praedictum principium ab aliquibus est erratum: et circa hoc duo facit. Primo tangit errorem illorum, qui contradicebant praedicto principio. Secundo eorum, qui ipsum demonstrare volebant, ibi, dignantur autem et cetera. Dicit ergo, quod quidam, sicut dictum est de Heraclito, dicebant quod contingit idem simul esse et non esse, et quod contingit hoc existimare. Et hac positione utuntur multi naturales, ut infra patebit: sed nos nunc accipimus supponendo praedictum principium esse verum, scilicet quod impossibile sit idem esse et non esse, sed ex sui veritate ostendimus quod est certissimum. Ex hoc enim quod impossibile est esse et non esse, sequitur quod impossibile sit contraria simul inesse eidem, ut infra dicetur. Et ex hoc quod contraria non possunt simul inesse, sequitur quod homo non possit habere contrarias opiniones, et per consequens quod non possit opinari contradictoria esse vera, ut ostensum est.	606. Now as we have said (329). Then he shows how some men erred regarding this principle; and in regard to this he does two things. First, he touches on the error of those who rejected the foregoing principle; and second (607) he deals with those who wished to demonstrate it (“But some”). He accordingly says that some men as was stated above about Heraclitus (601), said that the same thing can both be and not be at the same time, and that it is possible to hold this opinion; and many of the philosophers of nature adopt this position, as will be made clear below (665). For our part, however, we now take as evident that the principle in question is true, i.e., the principle that the same thing cannot both be and not be; but from its truth we show that it is most certain. For from the fact that a thing cannot both be and not be it follows that contraries cannot belong to the same subject, as will be said below (663). And from the fact that contraries cannot belong to a subject at the same time it follows that a man cannot have contrary opinions and, consequently, that he cannot think that contradictories are true, as has been shown (603).
lib. 4 l. 6 n. 12 Deinde cum dicit dignantur autem tangit errorem quorumdam, qui praedictum principium demonstrare volebant: et circa hoc duo facit. Primo ostendit quod non possit demonstrari simpliciter. Secundo quod aliquo modo potest demonstrari, ibi, est autem demonstrare et cetera. Dicit ergo primo, quod quidam dignum ducunt, sive volunt demonstrare praedictum principium. Et hoc propter apaedeusiam, idest ineruditionem sive indisciplinationem. Est enim ineruditio, quod homo nesciat quorum oportet quaerere demonstrationem, et quorum non: non enim possunt omnia demonstrari. Si enim omnia demonstrarentur, cum idem per seipsum non demonstretur, sed per aliud, oporteret esse circulum in demonstrationibus. Quod esse non potest: quia sic idem esset notius et minus notum, ut patet in primo posteriorum. Vel oporteret procedere in infinitum. Sed, si in infinitum procederetur, non esset demonstratio; quia quaelibet demonstrationis conclusio redditur certa per reductionem eius in primum demonstrationis principium: quod non esset si in infinitum demonstratio sursum procederet. Patet igitur, quod non sunt omnia demonstrabilia. Et si aliqua sunt non demonstrabilia, non possunt dicere quod aliquod principium sit magis indemonstrabile quam praedictum.	607. But some (330). Then he mentions the error of certain men who wished to demonstrate the above-mentioned principle; and in regard to this he does two things. First, he shows that it cannot be demonstrated in the strict sense; and second (608), that it can be demonstrated in a way (“But even”). Thus he says, first , that certain men deem it fitting, i.e., they wish, to demonstrate this principle; and they do this “through want of education,” i.e., through lack of learning or instruction. For there is want of education when a man does not know what to seek demonstration for and what not to; for not all things can be demonstrated. For if all things were demonstrable, then, since a thing is not demonstrated through itself but through something else, demonstrations would either be circular (although this cannot be true, because then the same thing would be both better known and less well known, as is clear in Book I of the Posterior Analytics, or they would have to proceed to infinity. But if there were an infinite regress in demonstrations, demonstration would be impossible, because the conclusion of any demonstration is made certain by reducing it to the first principle of demonstration. But this would not be the case if demonstration proceeded to infinity in an upward direction. It is clear, then, that not all things are demonstrable. And if some things are not demonstrable, these men cannot say that any principle is more indemonstrable than the above-mentioned one.
lib. 4 l. 6 n. 13 Est autem hic ostendit, quod aliquo modo potest praedictum principium demonstrari; dicens, quod contingit praedictum principium demonstrari argumentative. In Graeco habetur elenchice, quod melius transfertur redarguitive. Nam elenchus est syllogismus ad contradicendum. Unde inducitur ad redarguendum aliquam falsam positionem. Et propter hoc isto modo ostendi potest, quod impossibile sit idem esse et non esse. Sed solum si ille qui ex aliqua dubitatione negat illud principium, dicit aliquid idest aliquid nomine significat. Si vero nihil dicit, derisibile est quaerere aliquam rationem ad illum qui nulla utitur ratione loquendo. Talis enim in hac disputatione, qui nihil significat, similis erit plantae. Animalia enim bruta etiam significant aliquid per talia signa.	608. But even in this case (331). Here he shows that the above-mentioned principle can be demonstrated in a certain respect. He says that it may be demonstrated by disproof. In Greek the word is evlegktikw/j, which is better translated as by refutation, for an e;legkoj is a syllogism that establishes the contradictory of a proposition, and so is introduced to refute some false position. And on these grounds it can be shown that it is impossible for the same thing both to be and not be. But this kind of argument can be employed only if the one who denies that principle because of difficulties “says something,” i.e., if he signifies something by a word. But if he says nothing, it is ridiculous to look for a reason against one who does not make use of reason in speaking; for in this dispute anyone who signifies nothing will be like a plant, for even brute animals signify something by such signs.
lib. 4 l. 6 n. 14 Differt enim demonstrare simpliciter principium praedictum, et demonstrare argumentative sive elenchice. Quia si aliquis vellet demonstrare simpliciter praedictum principium, videretur petere principium, quia non posset aliquid sumere ad eius demonstrationem, nisi aliqua quae ex veritate huius principii dependerent, ut ex praedictis patet. Sed quando demonstratio non erit talis, scilicet simpliciter, tunc est argumentatio sive elenchus et non demonstratio.	609. For it is one thing to give a strict demonstration of this principle, and another to demonstrate it argumentatively or by refutation. For if anyone wished to give a strict demonstration of this principle, he would seem to be begging the question, because any principle that he could take for the purpose of demonstrating this one would be one of those that depend on the truth of this principle, as is clear from what has been said above (330:C 607). But when the demonstration is not of this kind, i.e., demonstration in the strict sense, there will then be disproof or refutation at most.
lib. 4 l. 6 n. 15 Alia litera sic habet et melius, alterius autem cum huius causa sit, argumentatio erit, et non demonstratio, idest cum huiusmodi processus a minus notis ad hoc magis notum principium fiat causa alterius hominis qui hoc negat, tunc poterit esse argumentatio sive elenchus, et non demonstratio, scilicet syllogismus contradicens ei poterit esse, cum id quod est minus notum simpliciter est concessum ab adversario, ex quo poterit procedi ad praedictum principium ostendendum quantum ad ipsum, licet non simpliciter.	610. Another text states this better by saying, “But when one argues for the sake of convincing another, there will then be refutation but not demonstration”; i.e., when a process of this kind from a less well known to a better known principle is employed for the sake of convincing another man who denies this, there will then be disproof or refutation but not demonstration; i.e., it will be possible to have a syllogism which contradicts his view, since what is less known absolutely is admitted by the opponent, and thus it will be possible to proceed to demonstrate the above-mentioned principle so far as the man is concerned but not in the strict sense.