Summa summae S. Thomae sive compendium theologiae

Although in what precedes we have proved that God knows all things, with none excepted; yet because there is a special difficulty concerning future things which depend on our free choice, by reason of the freedom that must be safeguarded, we therefore institute a special question concerning these.

I say: God certainly and infallibly knows all future things, absolute, contingent, and free, freedom remaining unharmed.

Proof of the first part, from Scripture and the Fathers. Psal. CXXXVIII, 3 and 4: Thou hast understood my thoughts afar off..., and hast foreseen all my ways. Ioann., VI, 65: Jesus knew from the beginning who they were that did not believe, and who he was that would betray him. The foreknowledge of future things is assigned as the surest token of divinity, Isa., XLI, 23: Shew the things that are to come hereafter, and we shall know that you are gods. Hence Tertullian, in the Apolog., ch. 20: « A fitting testimony of divinity, he says, is the truth of divination. » And Augustine, bk. V de Civit., ch. 9, against Cicero: « To confess that God exists and to deny the foreknowledge of future things, is the most manifest madness. »

Proof by manifold reason. 1° The knowledge of God, as having the will joined to it, makes future things, as I said above. Therefore he knows them. And granted that future things are not made by the knowledge of God, it is certain at least that they do not come to be, except with God willing or permitting. Therefore he knows them in his will as in their cause. 2° The future contingent, for example this one: The Antichrist will be, has a determinate truth. Therefore it is known by God who understands infinitely. — Proof of the antecedent. This proposition: The Antichrist will be, has its own assertoric truth [de inesse]; at some time it will be just as is signified by it. Therefore it is determinately true, no less than a proposition about the past which had its own assertoric truth, as this one: Peter sinned. 3° God knows things while he actually produces them outwardly. Therefore he knew them beforehand, otherwise his knowledge would be variable.

But when you hear that certain Fathers deny foreknowledge to God, understand this of foreknowledge as to the name; because, since the things that are future to us are present to God, as I shall presently say, he does not have, properly and strictly speaking, foreknowledge of them, but knowledge.

Proof of the second part. 1° God sees future things not only according to the state which they have in their contingent causes before they come to be, but he sees them in the now of eternity according to the state which they have in their presentiality¹. But the knowledge of a present thing is certain and infallible, nor does its contingency stand in the way of this at all; for when I see Socrates sitting, my knowledge is infallible and certain, yet no necessity is thereby imposed on Socrates. Therefore.

2° God foresees and provides for future things, not only as to their substance, but also as to their mode of necessity and contingency, as St. Thomas often insists. Therefore, from the fact that he knows future contingents certainly and infallibly, it not only does not follow that they will happen necessarily, but rather it follows for certain that they will happen contingently and freely, otherwise his foreknowledge would be deceived. Therefore this foreknowledge does nothing to harm the contingency of things.

3° The certain and infallible foreknowledge of future things, taken precisely under the office of foreknowledge, changes nothing in future things or in their causes, but has only to know what is going to happen, and how. Therefore, this notwithstanding, things that are contingent will happen contingently, and things that are necessary, necessarily; and it suffices for this certain and infallible knowledge that it have a certain and infallible medium in which the things that are future are represented to it. For the state of things in the mind of the knower is one thing, and in themselves another; and just as things that are necessary in themselves can be known contingently, so things that are contingent in their causes can be known with certainty, provided of course that the medium of knowledge is certain. Necessity or contingency is in things and from things; but the certainty or uncertainty of knowledge is in the mind, by reason of the medium. Therefore.

[That the explanation given here for establishing the agreement of divine foreknowledge with human freedom is according to the mind of St. Augustine, is plainly proved by the following words of his, by which he overturns Cicero's argumentation, bk. V De civit. Dei, ch. 9: « What is it, then, that Cicero feared in the foreknowledge of future things, that he strove to undermine it with a detestable disputation? Namely, because, if all future things are foreknown, they will come in that order in which they have been foreknown to be going to come; and, if they will come in that order, the order of things is certain to God who foreknows it; and, if the order of things is certain, the order of causes is certain — for nothing can come to be which some efficient cause has not preceded; but if the order of causes by which everything that happens comes to happen is certain, « by fate, he says, » all things that will happen will happen. » But if this is so, nothing is in our power, and there is no free choice of the will. « But if we grant this, he says, all human life is subverted; in vain are laws given, in vain rebukes, praises, » reproaches, exhortations are employed; nor has any justice established rewards for the good and punishments for the evil. » « Therefore, lest these unworthy, absurd, and pernicious consequences for human affairs should follow, he is unwilling that there be foreknowledge of future things. »]

Having set forth Cicero's opinion, the Holy Doctor replies, among many things, as follows: « We cannot deny that it is written in the Holy Scriptures, Ps. LXI, 12 and 13: God hath spoken once, these two things have I heard: that power belongeth to God, and mercy to thee, O Lord; for thou wilt render to every man according to his works. For what is said, he has spoken once, is understood immovably — that is, he has spoken unchangeably, just as he unchangeably knows all things that are future, and the things that he himself is going to do. For this reason, then, we could call it fate from fando, were this name not usually understood in another sense, toward which we do not wish the hearts of men to be inclined. But it does not follow that, if the order of all causes is certain to God, therefore nothing is in the choice of our will. For indeed our very wills themselves are in the order of causes, which is certain to God and is contained in his foreknowledge; since human wills too are the causes of human works. And thus he who foreknew all the causes of things, could certainly not have been ignorant, among those causes, of our wills also, which he foreknew to be the causes of our works. »

And further on: « If (Cicero) confesses that God exists, whom he denies to be foreknowing of future things, he also thereby says nothing other than what that one says, Psal. XIII, 1: The fool has said in his heart: There is no God. For he who is not foreknowing of all future things, is assuredly not God. Wherefore our wills too avail only so much as God willed and foreknew that they would avail; and therefore whatever they avail, they avail most certainly, and what they are going to do, they are altogether going to do: because he foreknew that they would avail and would act, whose foreknowledge cannot be deceived. »

And elsewhere, perhaps more expressly, bk. III de Libero arbitrio, ch. 3, n. 8: « Consider, I ask, with how great blindness it is said: If God foreknew my future will, then, since nothing can happen otherwise than he foreknew, it is necessary that I will what he foreknew; but if it is necessary, it must be confessed that I will this not now by will, but by necessity. O singular folly! How, then, can nothing else happen than what God foreknew, if the will — which he foreknew as future — should not exist?... Thus it comes about that we neither deny that God is foreknowing of all future things, and yet we ourselves will what we will. For since he is foreknowing of our will, it is that very will of which he is foreknowing. The will, therefore, will exist, because he is foreknowing of the will. Nor can the will exist, if it will not be in its power. Therefore he is also foreknowing of the power. Not, therefore, is power taken from me by his foreknowledge — which will indeed be the more certain to me for this very reason, because he whose foreknowledge cannot be deceived foreknew that it would be present to me. »

You have in these words of Augustine that the cause of the acts of the will is the foreknowledge of God, and accordingly that those future acts are seen as coming from God predetermining them in his foreknowledge; which is the very same opinion of the Thomists.