Commentaria in Summam contra Gentiles, Liber II

The conclusion having been proved, and the false opinion of Origen and Plato refuted, the arguments brought forward in support of the opinion of Plato and Origen must now be answered ¹.

I. To the first, then, the reply is given, granting that the soul has the power to be everlasting; and it is said first that from the fact that the soul has the power to be everlasting, it cannot be concluded that it always was, but only that it always will be: because the power and potentiality of a thing does not extend to what has been, as though it could bring that about, but only to what is or will be.

It is said second, that from that power of existing always it cannot be concluded that the soul exists always, unless it is posited that the soul has had this power from eternity: because that to which a power is ordered does not follow unless the power is presupposed.

Note that from that response the following proposition is denied: Of that which has the power to be always, it is never true to say that it is not. For this is not true except of that which has such a power from eternity. — Nor is there any proof. For it is indeed true that, as far as the power of being extends, so long does the esse of the thing last; yet the power of being extends only to what is to come after such a power is in the thing. Therefore it does not follow that the thing has lasted from eternity, but that it will always last.

2. But against this reply one could argue from the words of the Commentator, I De Caelo, commentary 136. For he wishes there that everything which has the power to be for an infinite time, whether it is posited to have been before for an infinite time and afterwards corrupted, or is posited to begin to be and afterwards to endure forever, has infinite power. For from this proposition the argument proceeds thus. If a substance which has the power to be forever in the future was not from eternity, it follows that by that power another power could be greater, namely that by which something is both from eternity and forever in the future. But this is impossible: because such a power is infinite, and nothing greater is given than the infinite. Therefore what has the power to be forever in the future is from eternity. And thus it is never true to say of it that it is not. The contrary of this was said in the reply.

3. It is answered, and it is said first, that a power existing in a thing for enduring through infinite time is not infinite intensively but only extensively: because that power itself is not the efficient cause of the esse of the thing, but only its formal cause. For to such a power there follows per se what follows to duality the even. Hence, just as intensive infinity of duality is not argued from the fact that it is always even, so intensive infinity of the power of being existing in a thing is not argued from the fact that by it something can endure through infinite time: but only extensive infinity and infinity of duration. Therefore its infinity must be spoken of as infinite duration is spoken of.

It is said second, that it is not unfitting for one infinite thing in duration to be greater than another infinite thing, when that thing is not infinite simply and in every respect. For time after this present instant, according to Aristotle, is infinite as lacking an end. And yet the whole of time, namely that which is infinite both with respect to what is past and with respect to what is to come, is greater than it: because the former is infinite only with respect to what is to come. So too the power of being through infinite time with respect to what is to come is infinite not simply, but only in a certain respect: therefore another greater power can be than it.

Hence from that proposition of the Commentator it cannot be concluded that what will always be has also always been. And even if the Commentator wished to take that proposition in this sense, that everything having the power of being for an infinite future time has infinite power, that is, by which it is for an infinite past time: a Catholic ought not to accept his authority on this point. But if his meaning is that everything having the power so as to be forever in future time has infinite power, that is, that it also has the power so as to have been able to endure for simply infinite time, this is granted: because, if it had been produced from eternity, it would endure for simply infinite time. Yet it does not follow from this that it was from eternity. On account of this Saint Thomas says in this reply that, although the soul has the power so as to be forever, it cannot nevertheless be concluded that it is forever, unless after it has received this power; and that, if it were taken that it had this power from eternity, there would be a begging of the question.

II. To the second argument the reply is given, and it is said first that from the eternity of the truth understood with respect to that which is understood, the eternity of the one understanding is not inferred; but it is indeed inferred from its eternity with respect to that by which it is understood. But then it is said that no truth, with respect to that by which the soul understands, is eternal in this way, although it is eternal in the first way: because the species by which our soul understands truth, as was shown above, come to it, namely anew. Therefore the consequence is denied.

It is said second, that from the fact that truths of this kind are understood to be eternal, it follows well that they are founded in something eternal. For they are founded in the first truth itself ² as in a universal cause containing all truth: to which our intellect is not related subjectively, but as to its proper end, since truth is the good of the intellect and its end.

It is said thirdly that, although the eternity of the soul cannot be proved from the eternity of truth understood, its immortality can nevertheless be proved. For just as concerning the beginning of a thing we can argue from the agent cause, so too we can take an argument concerning the duration of a thing from its end: that which is ordered to an everlasting end must be capable of perpetual duration. But from the eternity of the agent its eternity cannot be proved, as is clear from what was said above in this Second Part.

2. Concerning this proposition, Truths understood are founded in the first truth itself, it must be known that this can have a threefold sense. The first is that they are founded in it according to some esse of nature: just as we say that an accident is founded in substance. — And thus it is not taken here. For the truth of an enunciation, if taken formally, does not have real esse, but only cognized esse, which is esse of reason.

The second is that it is founded in it as the known in the knower, as if these truths were eternal because they are known eternally by God. — This sense, too, is not what is intended here, although it contains truth. It is indeed true that God knows them eternally. Yet for this reason they are not properly said to be founded in divine truth as truth: because according to this sense, for a truth to be founded in something is to be in it by way of a known object. But first truth, as such, does not have the character of a knower, but rather of the known: since the true is the object of intellect.

The third sense is that a proposition is said to be true on the basis of its being founded in the first truth as in that with respect to which and in proportion to which it is measured—that is, founded as in its measure: in the way in which we say that the truth of our intellect is founded in the esse of a thing, namely because the intellect is true when it understands things to be so just as they are in the thing ³. — And this is the sense intended here. For every truth of a proposition is measured by the truth existing in the divine intellect: because a proposition or a thing is true precisely insofar as it conforms to the ideas which are in the divine mind, in which divine truth consists. For every truth is necessary in some way: either it is absolutely necessary, as that man is an animal; or it is necessary for some determinate time, as Socrates sitting is necessary for that time for which he sits. And thus every truth is eternal, because it has its foundation in the eternal divine truth. For just as the divine idea eternally represents man with animality for every difference of time, so it eternally represents Socrates with his sitting at such a time. Therefore this proposition is eternally true, Man is an animal; and likewise this one, Socrates sits, referred to the time in which he sits. For supposing that Socrates sat only yesterday, it is true today that Socrates sits, if the particle "sits" refers not to the present time of those who are alive today, but to the time measuring the sitting of Socrates, which time is past for them. But enough has been said about these matters in Book One ⁴, where we spoke of divine cognition with respect to contingents. — Saint Thomas intimates this third sense when he says that they are founded in the first truth as in a universal cause containing all truth. For the first truth is the exemplary cause of all complex truths, and their measure. But of the truths which are in things it is also the productive cause: because the truth of a thing is nothing other than its esse; and every esse of created things is produced by God.

3. Concerning what is said, since the soul is not compared to that eternal thing in which truth is grounded as a subject to a form, it must be noted that by this Saint Thomas wishes to assign the reason why from the incorruptibility of the intelligible the immortality of the soul is argued, but its eternity is not argued from the eternity of the intelligible. For the material intelligible existing in these lower things is not incorruptible except according to the intelligible form it has in the intellect, to which the soul is compared as a subject to its perfection. And therefore, because what is perfectible must be proportioned to its perfection, it follows, as was argued above ⁵, that if that form itself is incorruptible, the soul too is incorruptible. But the intelligible does not have eternal esse according to the species it has in the intellect; rather, that eternal thing on which the eternal truth of intelligibles is grounded is not in the intellect as its form. Therefore from the eternity of the intelligible the eternity of the intellect cannot be argued.

To the third argument, which is in favor of the opinion of Origen, it is answered by denying the consequence. For the perfection of the universe is considered with respect to species, not with respect to individuals, since individuals are continually being added to the universe. Human souls, however, are distinct only in number.

From this it is also clear with respect to the fourth argument. For it is said that, just as the consummation of creatures is considered with respect to species, so the rest of God is to be understood as a cessation from creating new species, but not from new individuals, whose similars in species have preceded them.

2. For the clarification of this answer, it must be noted, according to the doctrine of St. Thomas, II Sent., d. XVII, q. II, a. 2, ad 6, that the perfection of the universe is twofold: namely essential and accidental. Therefore, when it is said here that the perfection of the universe is considered with respect to species, but not with respect to individuals, this is understood with respect to its essential perfection, not with respect to its accidental perfection; for individuals pertain to the accidental perfection of the universe. But what lacks accidental perfection is said to be imperfect only in a qualified sense: just as a man lacking a bishopric is not said to be an imperfect man.

It must be known, second, that this response—insofar as it holds that souls newly created were preceded according to species—proceeds according to the opinion of those who said that all things were produced according to species in the works of the six days; for thus, since man was produced in those six days, the souls of the first parents preceded the souls that are continually created. But according to Augustine's mind, who held that in the first production of things plants and animals were not produced in act ⁶, it must be said that souls were preceded in that creation not indeed in a likeness according to species, but, as is said Prima, q. xc, a. 4, and II Sent., where above ⁷, in a likeness according to genus, insofar as the soul agrees with the angels in intellectual nature, which were created in the first institution.

3. But a doubt arises. For those things that are perpetual both according to species and according to individual belong to the essential perfection of the universe, as is said in De Veritate, q. 5, a. 3. But the soul is perpetual both according to species and according to individual. Therefore it also belongs to the essential perfection of the universe according to individual, which is the opposite of what is said here.

It is answered, according to the doctrine of Saint Thomas (Potentia, q. III, a. 10, ad 4), that the perfection of the universe is twofold: namely, the first and the last. The soul, with respect to individuals, belongs to the ultimate perfection of the universe: because, as is said there, the whole transmutation of bodies is in a certain way ordered to the multiplication of souls, for which the multiplication of bodies is required. But it does not belong to the first perfection. Here, then, Saint Thomas speaks of the first essential perfection of the universe. In the Quaestiones de Veritate, however, he speaks of the essential perfection indistinctly, whether it be, I say, the first or the second. Hence there is no contradiction.

IV. Finally, because Saint Thomas had said in the preceding chapter that the words of Aristotle sound as if the soul were eternal, since he said that the intellect is perpetual, lest anyone think that this was Aristotle's mind, he removes this, saying that Aristotle never said that the human intellect is eternal; but he did indeed say that it is perpetual, which can be said of those things that will always exist, even though they have not always existed. That it was not his mind that the intellect is eternal is clear, because in Book XII of the Metaphysics ⁸ it would have been fitting for him to say something about this, since there he excepted the intellective soul from the condition of the other forms; and yet he did not say that it existed before matter (which Plato nevertheless said of the ideas), but only that it remains after the body.