Thomas Aquinas, Summa Theologiae

Objection 1: It seems that the knowledge of God is not of future contingent things. For from a necessary cause proceeds a necessary effect. But the knowledge of God is the cause of things known, as said above (Article 8). Since therefore that knowledge is necessary, what He knows must also be necessary. Therefore the knowledge of God is not of contingent things.

Objection 2: Further, every conditional proposition of which the antecedent is absolutely necessary must have an absolutely necessary consequent. For the antecedent is to the consequent as principles are to the conclusion: and from necessary principles only a necessary conclusion can follow, as is proved in Poster. i. But this is a true conditional proposition, "If God knew that this thing will be, it will be," for the knowledge of God is only of true things. Now the antecedent conditional of this is absolutely necessary, because it is eternal, and because it is signified as past. Therefore the consequent is also absolutely necessary. Therefore whatever God knows, is necessary; and so the knowledge of God is not of contingent things.

Objection 3: Further, everything known by God must necessarily be, because even what we ourselves know, must necessarily be; and, of course, the knowledge of God is much more certain than ours. But no future contingent things must necessarily be. Therefore no contingent future thing is known by God.

On the contrary, It is written (Ps. 32:15), "He Who hath made the hearts of every one of them; Who understandeth all their works," i.e. of men. Now the works of men are contingent, being subject to free will. Therefore God knows future contingent things.

I answer that, Since as was shown above (Article 9), God knows all things; not only things actual but also things possible to Him and creature; and since some of these are future contingent to us, it follows that God knows future contingent things.

In evidence of this, we must consider that a contingent thing can be considered in two ways; first, in itself, in so far as it is now in act: and in this sense it is not considered as future, but as present; neither is it considered as contingent (as having reference) to one of two terms, but as determined to one; and on account of this it can be infallibly the object of certain knowledge, for instance to the sense of sight, as when I see that Socrates is sitting down. In another way a contingent thing can be considered as it is in its cause; and in this way it is considered as future, and as a contingent thing not yet determined to one; forasmuch as a contingent cause has relation to opposite things: and in this sense a contingent thing is not subject to any certain knowledge. Hence, whoever knows a contingent effect in its cause only, has merely a conjectural knowledge of it. Now God knows all contingent things not only as they are in their causes, but also as each one of them is actually in itself. And although contingent things become actual successively, nevertheless God knows contingent things not successively, as they are in their own being, as we do but simultaneously. The reason is because His knowledge is measured by eternity, as is also His being; and eternity being simultaneously whole comprises all time, as said above (Question 10, Article 2). Hence all things that are in time are present to God from eternity, not only because He has the types of things present within Him, as some say; but because His glance is carried from eternity over all things as they are in their presentiality. Hence it is manifest that contingent things are infallibly known by God, inasmuch as they are subject to the divine sight in their presentiality; yet they are future contingent things in relation to their own causes.

Reply to Objection 1: Although the supreme cause is necessary, the effect may be contingent by reason of the proximate contingent cause; just as the germination of a plant is contingent by reason of the proximate contingent cause, although the movement of the sun which is the first cause, is necessary. So likewise things known by God are contingent on account of their proximate causes, while the knowledge of God, which is the first cause, is necessary.

Reply to Objection 2: Some say that this antecedent, "God knew this contingent to be future," is not necessary, but contingent; because, although it is past, still it imports relation to the future. This however does not remove necessity from it; for whatever has had relation to the future, must have had it, although the future sometimes does not follow. On the other hand some say that this antecedent is contingent, because it is a compound of necessary and contingent; as this saying is contingent, "Socrates is a white man." But this also is to no purpose; for when we say, "God knew this contingent to be future," contingent is used here only as the matter of the word, and not as the chief part of the proposition. Hence its contingency or necessity has no reference to the necessity or contingency of the proposition, or to its being true or false. For it may be just as true that I said a man is an ass, as that I said Socrates runs, or God is: and the same applies to necessary and contingent. Hence it must be said that this antecedent is absolutely necessary. Nor does it follow, as some say, that the consequent is absolutely necessary, because the antecedent is the remote cause of the consequent, which is contingent by reason of the proximate cause. But this is to no purpose. For the conditional would be false were its antecedent the remote necessary cause, and the consequent a contingent effect; as, for example, if I said, "if the sun moves, the grass will grow."

Therefore we must reply otherwise; that when the antecedent contains anything belonging to an act of the soul, the consequent must be taken not as it is in itself, but as it is in the soul: for the existence of a thing in itself is different from the existence of a thing in the soul. For example, when I say, "What the soul understands is immaterial," this is to be understood that it is immaterial as it is in the intellect, not as it is in itself. Likewise if I say, "If God knew anything, it will be," the consequent must be understood as it is subject to the divine knowledge, i.e. as it is in its presentiality. And thus it is necessary, as also is the antecedent: "For everything that is, while it is, must be necessarily be," as the Philosopher says in Peri Herm. i.

Reply to Objection 3: Things reduced to act in time, as known by us successively in time, but by God (are known) in eternity, which is above time. Whence to us they cannot be certain, forasmuch as we know future contingent things as such; but (they are certain) to God alone, whose understanding is in eternity above time. Just as he who goes along the road, does not see those who come after him; whereas he who sees the whole road from a height, sees at once all travelling by the way. Hence what is known by us must be necessary, even as it is in itself; for what is future contingent in itself, cannot be known by us. Whereas what is known by God must be necessary according to the mode in which they are subject to the divine knowledge, as already stated, but not absolutely as considered in their own causes. Hence also this proposition, "Everything known by God must necessarily be," is usually distinguished; for this may refer to the thing, or to the saying. If it refers to the thing, it is divided and false; for the sense is, "Everything which God knows is necessary." If understood of the saying, it is composite and true; for the sense is, "This proposition, 'that which is known by God is' is necessary."

Now some urge an objection and say that this distinction holds good with regard to forms that are separable from the subject; thus if I said, "It is possible for a white thing to be black," it is false as applied to the saying, and true as applied to the thing: for a thing which is white, can become black; whereas this saying, " a white thing is black" can never be true. But in forms that are inseparable from the subject, this distinction does not hold, for instance, if I said, "A black crow can be white"; for in both senses it is false. Now to be known by God is inseparable from the thing; for what is known by God cannot be known. This objection, however, would hold if these words "that which is known" implied any disposition inherent to the subject; but since they import an act of the knower, something can be attributed to the thing known, in itself (even if it always be known), which is not attributed to it in so far as it stands under actual knowledge; thus material existence is attributed to a stone in itself, which is not attributed to it inasmuch as it is known.

Articulus 13

Argumentum 1

Ad decimumtertium sic proceditur. Videtur quod scientia dei non sit futurorum contingentium. A causa enim necessaria procedit effectus necessarius. Sed scientia dei est causa scitorum, ut supra dictum est.

Cum ergo ipsa sit necessaria, sequitur scita eius esse necessaria. Non ergo scientia dei est contingentium.

Argumentum 2

Praeterea, omnis conditionalis cuius antecedens est necessarium absolute, consequens est necessarium absolute. Sic enim se habet antecedens ad consequens, sicut principia ad conclusionem, ex principiis autem necessariis non sequitur conclusio nisi necessaria, ut in I poster. Probatur.

Sed haec est quaedam conditionalis vera, si deus scivit hoc futurum esse, hoc erit, quia scientia dei non est nisi verorum. Huius autem conditionalis antecedens est necessarium absolute, tum quia est aeternum; tum quia significatur ut praeteritum. Ergo et consequens est necessarium absolute. Igitur quidquid scitur a deo, est necessarium. Et sic scientia dei non est contingentium.

Argumentum 3

Praeterea, omne scitum a deo necesse est esse, quia etiam omne scitum a nobis necesse est esse, cum tamen scientia dei certior sit quam scientia nostra. Sed nullum contingens futurum necesse est esse. Ergo nullum contingens futurum est scitum a deo.

Sed Contra

Sed contra est quod dicitur in Psalmo XXXII, qui finxit singillatim corda eorum, qui intelligit omnia opera eorum, scilicet hominum. Sed opera hominum sunt contingentia, utpote libero arbitrio subiecta. Ergo deus scit futura contingentia.

Corpus

Respondeo dicendum quod, cum supra ostensum sit quod deus sciat omnia non solum quae actu sunt, sed etiam quae sunt in potentia sua vel creaturae; horum autem quaedam sunt contingentia nobis futura; sequitur quod deus contingentia futura cognoscat. Ad cuius evidentiam, considerandum est quod contingens aliquod dupliciter potest considerari. Uno modo, in seipso, secundum quod iam actu est. Et sic non consideratur ut futurum, sed ut praesens, neque ut ad utrumlibet contingens, sed ut determinatum ad unum. Et propter hoc, sic infallibiliter subdi potest certae cognitioni, utpote sensui visus, sicut cum video socratem sedere. Alio modo potest considerari contingens, ut est in sua causa. Et sic consideratur ut futurum, et ut contingens nondum determinatum ad unum, quia causa contingens se habet ad opposita. Et sic contingens non subditur per certitudinem alicui cognitioni. Unde quicumque cognoscit effectum contingentem in causa sua tantum, non habet de eo nisi coniecturalem cognitionem. Deus autem cognoscit omnia contingentia, non solum prout sunt in suis causis, sed etiam prout unumquodque eorum est actu in seipso. Et licet contingentia fiant in actu successive, non tamen deus successive cognoscit contingentia, prout sunt in suo esse, sicut nos, sed simul. Quia sua cognitio mensuratur aeternitate, sicut etiam suum esse, aeternitas autem, tota simul existens, ambit totum tempus, ut supra dictum est.

Unde omnia quae sunt in tempore, sunt deo ab aeterno praesentia, non solum ea ratione qua habet rationes rerum apud se praesentes, ut quidam dicunt, sed quia eius intuitus fertur ab aeterno super omnia, prout sunt in sua praesentialitate. Unde manifestum est quod contingentia et infallibiliter a deo cognoscuntur, inquantum subduntur divino conspectui secundum suam praesentialitatem, et tamen sunt futura contingentia, suis causis comparata.

Ad 1

Ad primum ergo dicendum quod, licet causa suprema sit necessaria, tamen effectus potest esse contingens, propter causam proximam contingentem, sicut germinatio plantae est contingens propter causam proximam contingentem, licet motus solis, qui est causa prima, sit necessarius. Et similiter scita a deo sunt contingentia propter causas proximas, licet scientia dei, quae est causa prima, sit necessaria.

Ad 2

Ad secundum dicendum quod quidam dicunt quod hoc antecedens, deus scivit hoc contingens futurum, non est necessarium, sed contingens, quia, licet sit praeteritum, tamen importat respectum ad futurum.

Sed hoc non tollit ei necessitatem, quia id quod habuit respectum ad futurum, necesse est habuisse, licet etiam futurum non sequatur quandoque.

Alii vero dicunt hoc antecedens esse contingens, quia est compositum ex necessario et contingenti; sicut istud dictum est contingens, socratem esse hominem album.

Sed hoc etiam nihil est. Quia cum dicitur, deus scivit esse futurum hoc contingens, contingens non ponitur ibi nisi ut materia verbi, et non sicut principalis pars propositionis, unde contingentia eius vel necessitas nihil refert ad hoc quod propositio sit necessaria vel contingens, vera vel falsa. Ita enim potest esse verum me dixisse hominem esse asinum, sicut me dixisse socratem currere, vel deum esse, et eadem ratio est de necessario et contingenti. Unde dicendum est quod hoc antecedens est necessarium absolute. Nec tamen sequitur, ut quidam dicunt, quod consequens sit necessarium absolute, quia antecedens est causa remota consequentis, quod propter causam proximam contingens est.

Sed hoc nihil est. Esset enim conditionalis falsa, cuius antecedens esset causa remota necessaria, et consequens effectus contingens, ut puta si dicerem, si sol movetur, herba germinabit. Et ideo aliter dicendum est, quod quando in antecedente ponitur aliquid pertinens ad actum animae, consequens est accipiendum non secundum quod in se est, sed secundum quod est in anima, aliud enim est esse rei in seipsa, et esse rei in anima. Ut puta, si dicam, si anima intelligit aliquid, illud est immateriale, intelligendum est quod illud est immateriale secundum quod est in intellectu, non secundum quod est in seipso. Et similiter si dicam, si deus scivit aliquid, illud erit, consequens intelligendum est prout subest divinae scientiae, scilicet prout est in sua praesentialitate.

Et sic necessarium est, sicut et antecedens, quia omne quod est, dum est, necesse est esse, ut dicitur in I periherm..

Ad 3

Ad tertium dicendum quod ea quae temporaliter in actum reducuntur, a nobis successive cognoscuntur in tempore, sed a deo in aeternitate, quae est supra tempus. Unde nobis, quia cognoscimus futura contingentia inquantum talia sunt, certa esse non possunt, sed soli deo, cuius intelligere est in aeternitate supra tempus.

Sicut ille qui vadit per viam, non videt illos qui post eum veniunt, sed ille qui ab aliqua altitudine totam viam intuetur, simul videt omnes transeuntes per viam. Et ideo illud quod scitur a nobis, oportet esse necessarium etiam secundum quod in se est, quia ea quae in se sunt contingentia futura, a nobis sciri non possunt. Sed ea quae sunt scita a deo, oportet esse necessaria secundum modum quo subsunt divinae scientiae, ut dictum est, non autem absolute, secundum quod in propriis causis considerantur.

Unde et haec propositio, omne scitum a deo necessarium est esse, consuevit distingui. Quia potest esse de re, vel de dicto.

Si intelligatur de re, est divisa et falsa, et est sensus, omnis res quam deus scit, est necessaria. Vel potest intelligi de dicto, et sic est composita et vera; et est sensus, hoc dictum, scitum a deo esse, est necessarium.

Sed obstant quidam, dicentes quod ista distinctio habet locum in formis separabilibus a subiecto; ut si dicam, album possibile est esse nigrum. Quae quidem de dicto est falsa, et de re est vera, res enim quae est alba, potest esse nigra; sed hoc dictum, album esse nigrum, nunquam potest esse verum. In formis autem inseparabilibus a subiecto, non habet locum praedicta distinctio; ut si dicam, corvum nigrum possibile est esse album, quia in utroque sensu est falsa. Esse autem scitum a deo, est inseparabile a re, quia quod est scitum a deo, non potest esse non scitum.

Haec autem instantia locum haberet, si hoc quod dico scitum, importaret aliquam dispositionem subiecto inhaerentem. Sed cum importet actum scientis, ipsi rei scitae, licet semper sciatur, potest aliquid attribui secundum se, quod non attribuitur ei inquantum stat sub actu sciendi, sicut esse materiale attribuitur lapidi secundum se, quod non attribuitur ei secundum quod est intelligibile.