Summa Theologica, Part I · Aquinas Thomas
QUESTION 14
Obj. 3: Further, the knowledge of God is the measure of what is known. But it is contrary to the essence of the infinite that it be measured. Therefore infinite things cannot be known by God. _On the contrary,_ Augustine says (De Civ. Dei xii), "Although we cannot number the infinite, nevertheless it can be comprehended by Him whose knowledge has no bounds." _I answer that,_ Since God knows not only things actual but also things possible to Himself or to created things, as shown above (A. 9), and as these must be infinite, it must be held that He knows infinite things. Although the knowledge of vision which has relation only to things that are, or will be, or were, is not of infinite things, as some say, for we do not say that the world is eternal, nor that generation and movement will go on for ever, so that individuals be infinitely multiplied; yet, if we consider more attentively, we must hold that God knows infinite things even by the knowledge of vision. For God knows even the thoughts and affections of hearts, which will be multiplied to infinity as rational creatures go on for ever.
The reason of this is to be found in the fact that the knowledge of every knower is measured by the mode of the form which is the principle of knowledge. For the sensible image in sense is the likeness of only one individual thing, and can give the knowledge of only one individual. But the intelligible species of our intellect is the likeness of the thing as regards its specific nature, which is participable by infinite particulars; hence our intellect by the intelligible species of man in a certain way knows infinite men; not however as distinguished from each other, but as communicating in the nature of the species; and the reason is because the intelligible species of our intellect is the likeness of man not as to the individual principles, but as to the principles of the species. On the other hand, the divine essence, whereby the divine intellect understands, is a sufficing likeness of all things that are, or can be, not only as regards the universal principles, but also as regards the principles proper to each one, as shown above. Hence it follows that the knowledge of God extends to infinite things, even as distinct from each other. Reply Obj. 1: The idea of the infinite pertains to quantity, as the Philosopher says (Phys. i). But the idea of quantity implies the order of parts. Therefore to know the infinite according to the mode of the infinite is to know part after part; and in this way the infinite cannot be known; for whatever quantity of parts be taken, there will always remain something else outside. But God does not know the infinite or infinite things, as if He enumerated part after part; since He knows all things simultaneously, and not successively, as said above (A. 7). Hence there is nothing to prevent Him from knowing infinite things.
Whether the Knowledge of God Is of Future Contingent Things? 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 (A. 8). Since therefore that knowledge is necessary, what He knows must also be necessary. Therefore the knowledge of God is not of contingent things. Obj. 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. Obj. 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 (A. 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 (Q. 10, A. 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 Obj. 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 Obj. 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 Obj. 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. _______________________ FOURTEENTH ARTICLE [I, Q. 14, Art. 14] Whether God Knows Enunciable Things? Objection 1: It seems that God does not know enunciable things. For to know enunciable things belongs to our intellect as it composes and divides. But in the divine intellect, there is no composition. Therefore God does not know enunciable things.
Obj. 2: Further, every kind of knowledge is made through some likeness. But in God there is no likeness of enunciable things, since He is altogether simple. Therefore God does not know enunciable things. _On the contrary,_ It is written: "The Lord knoweth the thoughts of men" (Ps. 93:11). But enunciable things are contained in the thoughts of men. Therefore God knows enunciable things. _I answer that,_ Since it is in the power of our intellect to form enunciations, and since God knows whatever is in His own power or in that of creatures, as said above (A. 9), it follows of necessity that God knows all enunciations that can be formed. Now just as He knows material things immaterially, and composite things simply, so likewise He knows enunciable things not after the manner of enunciable things, as if in His intellect there were composition or division of enunciations; for He knows each thing by simple intelligence, by understanding the essence of each thing; as if we by the very fact that we understand what man is, were to understand all that can be predicated of man. This, however, does not happen in our intellect, which discourses from one thing to another, forasmuch as the intelligible species represents one thing in such a way as not to represent another. Hence when we understand what man is, we do not forthwith understand other things which belong to him, but we understand them one by one, according to a certain succession. On this account the things we understand as separated, we must reduce to one by way of composition or division, by forming an enunciation. Now the species of the divine intellect, which is God's essence, suffices to represent all things. Hence by understanding His essence, God knows the essences of all things, and also whatever can be accidental to them.
Reply Obj. 1: This objection would avail if God knew enunciable things after the manner of enunciable things. Reply Obj. 2: Enunciatory composition signifies some existence of a thing; and thus God by His existence, which is His essence, is the similitude of all those things which are signified by enunciation. _______________________ FIFTEENTH ARTICLE [I, Q. 14, Art. 15] Whether the Knowledge of God Is Variable? Objection 1: It seems that the knowledge of God is variable. For knowledge is related to what is knowable. But whatever imports relation to the creature is applied to God from time, and varies according to the variation of creatures. Therefore the knowledge of God is variable according to the variation of creatures. Obj. 2: Further, whatever God can make, He can know. But God can make more than He does. Therefore He can know more than He knows. Thus His knowledge can vary according to increase and diminution. Obj. 3: Further, God knew that Christ would be born. But He does not know now that Christ will be born; because Christ is not to be born in the future. Therefore God does not know everything He once knew; and thus the knowledge of God is variable. _On the contrary,_ It is said, that in God "there is no change nor shadow of alteration" (James 1:17).
_I answer that,_ Since the knowledge of God is His substance, as is clear from the foregoing (A. 4), just as His substance is altogether immutable, as shown above (Q. 9, A. 1), so His knowledge likewise must be altogether invariable. Reply Obj. 1: "Lord", "Creator" and the like, import relations to creatures in so far as they are in themselves. But the knowledge of God imports relation to creatures in so far as they are in God; because everything is actually understood according as it is in the one who understands. Now created things are in God in an invariable manner; while they exist variably in themselves. We may also say that "Lord", "Creator" and the like, import the relations consequent upon the acts which are understood as terminating in the creatures themselves, as they are in themselves; and thus these relations are attributed to God variously, according to the variation of creatures. But "knowledge" and "love," and the like, import relations consequent upon the acts which are understood to be in God; and therefore these are predicated of God in an invariable manner.
Reply Obj. 2: God knows also what He can make, and does not make. Hence from the fact that He can make more than He makes, it does not follow that He can know more than He knows, unless this be referred to the knowledge of vision, according to which He is said to know those things which are in act in some period of time. But from the fact that He knows some things might be which are not, or that some things might not be which are, it does not follow that His knowledge is variable, but rather that He knows the variability of things. If, however, anything existed which God did not previously know, and afterwards knew, then His knowledge would be variable. But this could not be; for whatever is, or can be in any period of time, is known by God in His eternity. Therefore from the fact that a thing exists in some period of time, it follows that it is known by God from eternity. Therefore it cannot be granted that God can know more than He knows; because such a proposition implies that first of all He did not know, and then afterwards knew.
SIXTEENTH ARTICLE [I, Q. 14, Art. 16] Whether God Has a Speculative Knowledge of Things? Objection 1: It seems that God has not a speculative knowledge of things. For the knowledge of God is the cause of things, as shown above (A. 8). But speculative knowledge is not the cause of the things known. Therefore the knowledge of God is not speculative. Obj. 2: Further, speculative knowledge comes by abstraction from things; which does not belong to the divine knowledge. Therefore the knowledge of God is not speculative. _On the contrary,_ Whatever is the more excellent must be attributed to God. But speculative knowledge is more excellent than practical knowledge, as the Philosopher says in the beginning of Metaphysics. Therefore God has a speculative knowledge of things.
_I answer that,_ Some knowledge is speculative only; some is practical only; and some is partly speculative and partly practical. In proof whereof it must be observed that knowledge can be called speculative in three ways: first, on the part of the things known, which are not operable by the knower; such is the knowledge of man about natural or divine thing[s]. Secondly, as regards the manner of knowing--as, for instance, if a builder consider a house by defining and dividing, and considering what belongs to it in general: for this is to consider operable things in a speculative manner, and not as practically operable; for operable means the application of form to matter, and not the resolution of the composite into its universal formal principles. Thirdly, as regards the end; "for the practical intellect differs in its end from the speculative," as the Philosopher says (De Anima iii). For the practical intellect is ordered to the end of the operation; whereas the end of the speculative intellect is the consideration of truth. Hence if a builder should consider how a house can be made, not ordering this to the end of operation, but only to know (how to do it), this would be only a speculative considerations as regards the end, although it concerns an operable thing. Therefore knowledge which is speculative by reason of the thing itself known, is merely speculative. But that which is speculative either in its mode or as to its end is partly speculative and partly practical: and when it is ordained to an operative end it is simply practical.
In accordance with this, therefore, it must be said that God has of Himself a speculative knowledge only; for He Himself is not operable. But of all other things He has both speculative and practical knowledge. He has speculative knowledge as regards the mode; for whatever we know speculatively in things by defining and dividing, God knows all this much more perfectly. Now of things which He can make, but does not make at any time, He has not a practical knowledge, according as knowledge is called practical from the end. But He has a practical knowledge of what He makes in some period of time. And, as regards evil things, although they are not operable by Him, yet they fall under His practical knowledge, like good things, inasmuch as He permits, or impedes, or directs them; as also sicknesses fall under the practical knowledge of the physician, inasmuch as he cures them by his art. Reply Obj. 1: The knowledge of God is the cause, not indeed of Himself, but of other things. He is actually the cause of some, that is, of things that come to be in some period of time; and He is virtually the cause of others, that is, of things which He can make, and which nevertheless are never made. Reply Obj. 2: The fact that knowledge is derived from things known does not essentially belong to speculative knowledge, but only accidentally in so far as it is human.
Ideas discussed in this chapter
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