Commentaria in Summam contra Gentiles, Liber I

After Saint Thomas had determined concerning the divine perfections pertaining to nature, he now determines concerning those that pertain to operation ¹. Concerning this he does two things: first he determines concerning the perfections by which something is known to be living; second, concerning life itself, chapter XCVII. Concerning the first he does two things: first, he treats of the perfections themselves; second, of the passions and virtues pertaining to those perfections, chapter LXXXIX. Concerning the first he does two things: first, he treats of the perfection which is intellect; second, of the perfection which is will, chapter LXXII.

On the first point he does two things: first, he treats of the divine cognition on the side of the one understanding; second, on the side of the object known, chapter XLVII. — On the first point he does two things: first, he treats of that cognition in itself; second, of it on the side of the medium of knowing ². — On the first point he does two things: first, he shows that God is an understanding being; second, that He is His own act of understanding, in the following chapter.

I. He therefore proves first that God is an intelligent being. And he first argues ³, supposing that one must arrive at a single first self-mover, as Aristotle demonstrates ⁴.

God is the first appetible, as the first understood by the first self-mover. Therefore He is intelligent. — The consequence is proved. Because what desires it becomes actually intelligent by being united to it as intelligible: since it is itself understood, it must be that what is intelligible is intelligent ⁵. — The antecedent too is proved thus. A self-mover, namely with local motion, moves itself through appetite and apprehension: because only such things have in themselves being moved and not being moved. Therefore the moving part is desiring and apprehending. But what desires and apprehends is a moved mover; whereas the appetible is a mover not moved. Therefore the first mover, altogether unmoved, which is God, is related to the moving part as appetible. But not as appetible through sensible appetite: for that is not of good simply, but of this particular good determined to here and now; yet the first mover must be good simply, since good and appetible simply are prior to good as here and now. Therefore the first mover is the first appetible and understood.

II. Concerning that proposition of Aristotle, Those things that move themselves have within themselves being moved and not being moved, which is found in Book VIII of the Physics ⁶, and which Saint Thomas intends here, it must be noted from his doctrine in the Verit., q. XXIV, a. 2, that the motive power in brute animals can be considered in two ways: in one way, in itself and absolutely; in another way, in relation to the judgment by which the motive power is applied to motion. Likewise, the action of the brute animal itself can be considered both in itself and in relation to the judgment from which it proceeds. If the motive power and the action of the brute animal are considered in the first way, they are no more determined to one thing than to another—in which they differ from natural things, which have forms determined to one thing and always act in the same way according to their own nature. And in this sense the Philosopher and Saint Thomas understand that all things which move themselves have within themselves being moved and not being moved. — But if they are considered in the second way, then they are determined to one thing: because they always follow judgment, and that judgment itself is determined for them by nature; just as a sheep, seeing a wolf, naturally judges it to be something to be fled from. And thus there is not in them being moved and not being moved: but this belongs only to a being possessing reason, whose judgment is not determined by nature.

III. Concerning this proposition, The appetizing and apprehending thing is a mover that is itself moved, while the appetible thing is a mover that is not moved, note that some Thomists ⁷ hold this proposition, which is Aristotle's, in Book III de Anima ⁸, to be understood of the mover by way of an efficient cause; wishing that the appetible object concur with the act of appetite by way of efficient cause, formal cause, and the reason of acting, as regards the specification of the act, but not as regards its exercise, yet being really distinct from the appetite itself; and not merely by way of final cause.

They prove this first ⁹, because otherwise Aristotle would have spoken equivocally of the mover in Book III of the Soul and Book XII of the Metaphysics ¹⁰, when he reduces the order of movers to one unmoved mover, namely the appetible object. For, since he intended to reduce them to a single mover acting efficiently, if the appetible were a mover only by way of an end, there would be a transition from end to efficient cause.

Second, because Averroes, in XII Metaphysics, commentary 36, says that the appetible moves the appetite in a twofold genus of cause: namely, efficiently, insofar as it is apprehended; and finally, insofar as it exists outside the soul.

Third. Since in appetite there are two things, namely its exercise and its specification, one must assign some efficient cause to the specification itself, just as to the exercise. But this cannot be the will alone: for then all its acts would be of the same species, as all actions are from heat. Therefore it will be the object itself, which is the appetible.

Fourth, because then the will would not be a passive power: the opposite of which Saint Thomas holds in the First Part, q. 80, a. 2. For it belongs to the notion of a passive power that it be moved effectively by its object: as is clear from Verit., q. 16, 1, ad 13.

Fifth. Subsistence joined to a cause does not change that cause's causality from one genus of causing to another. But the subsistent Word causes Love in the manner of an efficient cause, as Saint Thomas holds ¹¹: indeed, it causes faith as well. Therefore also the non-subsistent word of our heart. But the word of the heart is nothing other than the apprehended object. Therefore, and so on.

Sixth. If this were not so, and we were to say that the appetite moves itself toward the presence of the desirable thing, there will be no effective way of proving that anything is acted upon by another. For we would say of the intellect with respect to the intelligible, of the sense with respect to the sensible, and of wood with respect to what burns it, that they are not acted upon, but that they move themselves toward the presence of those things.

Others hold that the appetible in no way moves by the mode of an efficient cause, whether total or partial, but only by the mode of a final cause: as Capreolus holds, II Sent., d. XXIV and XXV.

IV. Although both opinions can be sustained, and each has most learned defenders, and each seems to be found in the words of St. Thomas — the first from the fact that he holds appetite to be a passive power ¹²; the second indeed from the fact that in the First Part, q. LXXXII ¹³, and in the First Part of the Second Part, q. IX ¹⁴, and in De Veritate, q. XXII ¹⁵, and everywhere, he seems firmly to hold that the appetible moves the intellect by the mode of an end; and he posits a different mode of motion between intellect and will, holding that the intellect moves the will only by the mode of an end, when it proposes the appetible to it, but that the will moves the intellect by the mode of an efficient cause: — nevertheless it seems to me that one must proceed along a middle way.

For the appetible, or the end, can be related to the will in two ways: in one way, with respect to that act by which it wills the end; in another way, with respect to that act by which it wills those things that are ordered to the end. I say, therefore, two things:

The first is that, if the end is compared to the will with respect to that act by which the will wills the end, it does not move the will efficiently, properly speaking, as a form which would be the elicitive principle of volition; rather, it moves the will only formally, in the manner of a form specifying an operation existing outside the operating power.

The second is that, if the end is compared to the will with respect to the volition of those things which are ordered to the end, the end moves the will in the manner of an efficient cause, as the reason for acting ¹⁶.

V. For the clarification of the first statement, it must first be known that, although what we call to move properly signifies among us the act and causality of the efficient cause, because that is more manifest than the causalities of the other causes, this term is nevertheless extended also to signify the causality of the end and of the form. Hence the end is said to move metaphorically and by similitude, because just as an agent draws its effect into a likeness of itself, so the desirable draws the will to itself: although in the efficient cause this occurs through the impression of some form or motion, whereas in the desirable and in the end it does not occur through the impression of anything in the will, but only through the determination and specification of the very act of the will, since the act of the will is terminated to this desirable object, precisely because it is apprehended, and not to another. Hence nothing else is meant by the will being moved by the end, with respect to the volition of that end, than its being inclined toward the end through the apprehension of the end itself. From which it also follows that, metaphorically, according to this consideration, the very power of the will is said to be passive, and the desirable object is said to be active, metaphorically: so that the former is called passive because it is indifferent to this or that object and can be drawn by it in some way; and the latter active because it draws the will to itself, as the formal specifier of its volition.

2. It must be known, second, that since the end, as appetible, is the reason for moving the will, because it is that for the love of which, or on account of which, the will acts and moves; and since the reason for acting must be in the agent: it is necessary, as is said in Verit., where above ¹⁷, that the appetible be in the appetent, not indeed according to natural esse, but according to intentional esse; so that intentional esse is the condition of the end insofar as it is the reason for moving, and insofar as it is the formal specifier of the act of the will. On account of which it is said that the end moves the agent insofar as it is in the intention: namely, because its intentional esse is the condition of the end itself required in order that it move, both formally and as the reason for acting; just as, in order that heat be the reason for the fire's heating, and in order that it make something formally hot, it must be in the fire.

Yet care must be taken lest it be thought that the will itself must know its own object in order to be inclined toward it; and this especially because Saint Thomas often says that the intellect moves the will inasmuch as it proposes its object to it ¹⁸. For this is not true, since animal appetite is not a cognitive power. But since the will is rooted in the same essence of the soul as the intellect, and the will itself is not properly what wills and appetes, but rather man is inclined through the will toward the appetible: it is indeed necessary that the appetible be known by the one who appetes it, so that his operation may be specified, but not by the will itself. Therefore, for the intellect to propose and present an object to the will is not to set it before the will as something to be known: rather, it is to place it in such a condition that in the one who has such an appetible according to its intentional esse, there follows an inclination of the will toward the natural esse of the appetible, as represented to the one who appetes by such intentional esse.

3. It must be known, thirdly, that the species of the specified act is not really distinct from the substance and nature of the act itself, but only according to reason: for the entity of heating is not distinct from the species of heating, but one and the same thing is the action itself and the heating. On this account one need not seek a particular efficient cause of the specification distinct from the efficient cause of the substance and entity of the act: otherwise, just as to the substance is attributed an efficient cause simply productive of it as that which acts, and not merely as the reason for producing, so too for the specification one would have to posit another cause, not merely one that would be the reason for acting, but one that would be the agent. Therefore that which is the cause of the substance of the act by way of an efficient cause is also the effective cause of the species: but the formal cause, from which the species is, is that which is the reason why it is such an act. Just as the cause of motion upward, both as regards the substance and as regards the species of the motion, by way of an efficient cause is the mover itself, which does not cause an indeterminate motion but a specified one: the formal cause, however, from which the motion upward is formally such, is the very terminus of the motion, so that the mover causes the motion thus specified because it moves the mobile thing to the place above. Similarly, therefore, in the case of the motion of appetite toward the end, one need not seek, as regards its specification, an efficient cause other than the appetite itself, but the appetite itself is the cause of the specified act: the formal reason, however, from which the act itself formally has that it is such an act, and the appetite itself has that it produces an act thus specified, is the very appetible object existing intelligibly in the one who appetes. Thus, therefore, in the volition of the end, the appetible object moves the appetite as regards the specification of the act, because it is the reason and form from which it formally has that its act is such: but it does not concur effectively in the act itself by way of eliciting the operation.

To this sense, then, Saint Thomas intends that the appetible moves the will by way of an end, with respect to the volition of the appetible itself as end: namely, because it is the form by which such a volition is specified.

VI. For the clarification of the second point, however ¹⁹, it must be considered that the will is not only the cause of its own act, but also of the external motion by which the end is acquired. But in such causality the will itself stands as agent, while the end stands as the reason for acting: just as in heating the substance of fire stands as that which heats, while heat stands as the reason for heating. And because the will causes nothing externally except through the mediation of an act of willing, therefore, when it causes a motion ordered to the attainment of the end, it also causes in itself the volition of that very motion, through which mediation it causes the motion. Hence, just as the end is for the will the reason for causing the motion, insofar as it does not cause the motion except on account of the attainment of the end; so too is it for the will itself the reason for causing in itself the volition of that motion which is ordered to the end: for it wills the very motion because it wills the end to be acquired through it. Hence the end, as willed, concurs actively, as the reason for acting, in the volition of what is toward the end: for the will, actualized by the volition of the end, elicits the volition of what is toward the end.

And thus what Saint Thomas says in the passage cited, ²⁰, namely that the end moves as the reason for moving, is understood with respect to extrinsic motion and to the volition of the motion itself ordered to the end, but not with respect to the volition of the end itself. And this is to move by way of an end with respect to those things that are for the sake of the end.

Thus, therefore, it is granted that in one way the end moves the will formally only, but in another way effectively.

VII. To the arguments for the first opinion ²¹, insofar as they seem to be against the first statement, the reply is given. To the first it is said that Aristotle did not equivocate about the mover, but argued with artfulness: from the fact that he shows the first mover must be altogether immobile, he shows that it also moves in the manner of an end, namely as the reason for moving and acting. For, since every mover that is not an end moves for the sake of an end other than itself, and is thus moved by another through the motion of the end toward the things that are for the sake of the end, it follows that that which is altogether immobile absolutely also moves in the manner of the desirable and the end; for this alone is a mover altogether immobile, because it is not moved by another as such. Hence Aristotle does not intend, as the argument supposes, to show that the first mover is immobile because it moves as the desirable; but on the contrary, because it is altogether immobile, he shows that it moves in the manner of the desirable, since it belongs to the desirable, in the order of voluntary motion, to be an immobile mover; for if it moved only in the manner of an efficient cause and not in the manner of an end, it would not be altogether immobile, because the end moves the efficient cause to act for the sake of that end, namely as that for the sake of which it moves and acts.

Likewise in III de Anima he does not commit an equivocation. For, since he wished to show that animals are moved by local motion through appetite, he considered in that order the character of mover and moved absolutely, and not the character of a mover that is only efficient or only final. For thus, since the end is the cause of causes, the appetible, which moves under the character of an end, has the character of an unmoved mover; but appetite has the character of mover and moved, inasmuch as it indeed moves efficiently, yet is itself moved by the motion of the end.

It is said further that reason concludes, if it concludes anything, that the end in some way effectively moves the will with respect to the volition of those things that are ordered to the end, but not with respect to the volition of the end itself.

To the second, it is said first that the Commentator speaks properly of the end by comparison to the motion which is ordered toward the acquisition of the end, as appears from his procedure. For thus the end, insofar as it is outside, causes motion in the manner of an end, inasmuch as the motion comes about for the sake of acquiring it according to the esse it has outside the soul—although the esse it has in the soul is a condition of its moving in this way. But insofar as it has esse in the soul, it causes motion in the manner of an efficient cause, inasmuch as the will, willing the end, effectively causes both the volition of the motion toward the end and the motion itself.

It is said second, that in comparison to the desire for an end, the Commentator's statement is understood improperly and with an extended use of the term. For the end in the soul, say a bath, is said to produce its desire formally, which is to produce improperly, just as we say that heat makes fire hot, but not properly by way of efficient causality.

To the third, it is clear from what has been said ²². For it has been shown that there need be no other efficient cause of the specification of the act besides the will itself, which elicits the act as specified.

But when it is proved that then all acts would be of the same species, the consequence is denied. For it does not suffice for acts to be of the same species that they are produced by the same efficient cause as specifically specified, but it is also required that there be the same specifying form: just as motion upward and motion downward, produced by the same mover and specified, are specifically distinct, notwithstanding that they are produced by the same mover, because they have different termini, by which they are formally specified. Now, not all acts of the will have the same form. Therefore not all are of the same species. Hence the will itself efficiently specifies its own acts, because it adapts and measures them to its forms, namely to diverse appetibles: just as one who gives the form by which a thing is specified is said to specify it efficiently. But the appetible itself specifies by way of an extrinsic form.

To the fourth, it is said first that the will is not a passive power with respect to volition of the end, if "passive" be taken as corresponding to what is truly active and efficient, so that a passive power would be one into which an object is naturally apt to produce some act or form. But if it be taken more broadly for anything indeterminate that is naturally apt to be determined by another in any way whatever and reduced to act, then it is a passive power: just as we might say that fire is a passive power with respect to the heat informing it. And this is how Saint Thomas understands it. Hence in Veritate, at the place cited above ²³, ad 3, he explains himself thus, saying that from the fact that the will is a passive power, and consequently can be moved by the object, nothing else follows except that the intellect moves the will by way of an end, because the good as apprehended moves it in this way.

It is said second, that it is properly passive with respect to volition of those things that are ordered to the end. And thus it is conceded that it is effectively moved by the desirable as by the reason for acting, in the manner explained above ²⁴

To the fifth it is said that it does not belong to the notion of a word to cause love by way of an efficient cause, but only by way of a specifying form. And when it is said that in the divine the Word produces Love by way of an efficient cause, it is said that this does not befit him as he is a word, but as he is the divine Word.

But when it is urged that subsistence does not vary the genus of causality, the reply is that this is false of divine subsistence. It is said, however, that this is not naturally known—namely, that the divine Word has the mode of efficient causality—but is held only by faith. And if one were to argue from the notion of a word found in our intellect, or absolutely from the notion of word, that the divine Word has the power to produce Love efficiently, this would not be an effective argument but a kind of accommodation to what we already hold by faith: for the trinity of Persons cannot be demonstrated. Hence that argument would prove nothing to the philosopher, since it proceeds from premises false according to him.

To the sixth, we say that the case of appetite is not like that of the others: because appetite names an inclination by its very definition, whereas intellect or stone does not. Hence, when the appetible is present in the one who has appetite, there follows an inclination of appetite in accordance with its own inclination; but in other things, even with the object or agent present, that which we say undergoes passion does not move itself.

VIII. But against the aforesaid determination a doubt remains from the words of St. Thomas in the Prima, q. 14, a. 5, ad 3, and in the First book of the Contra Gentiles, c. 48, and in other places. For he holds that every operation is specified by the form which is the principle of the operation. From these texts, however, the argument is drawn as follows. An operation is specified by the form which is the principle of the operation. But the act of the will is specified by the appetible object, by you. Therefore the appetible object is the form which is the principle of volition. Therefore the appetible object moves the will in the manner of an efficient formal cause. The opposite of which was said above ²⁵.

It is answered that certainly every operation is specified by the form which is the principle of that operation; but that form is the principle of operation is not understood in the same way in all agents. For in natural agents, the form is a principle by the mode of eliciting the operation. But in agents acting through cognition and from appetite for an end, the end itself as known is the principle of that operation which is the volition of the end—not, however, as eliciting the operation; hence it is not in the will, which is the immediate elicitive principle of volition, but in its intellect, as a form existing in the willing subject prior to volition, from which, once it exists in his intellect, volition proceeds. Hence the known end is said to be the principle of volition, insofar as every form which preexists in the agent before the operation according to nature, and by which, once posited, the agent himself proceeds to action, can be called the principle of the operation—although it does not formally elicit that operation, but only specifies it.

IX. Concerning the proof of the consequence ²⁶ no small doubt arises. For this consequence does not hold: The one desiring God becomes actually understanding by the fact that it is united to Him as to something intelligible; therefore the intelligible itself is understanding. For by the same reasoning stone and wood and other material things would be understanding, since man is actually understanding because he is united to them as to intelligibles through their species.

Because Saint Thomas took this argument from Metaphysics XII, text 39 ²⁷, the solution to the doubt must be sought from there. Therefore, for the clarification of this, it must be considered that, since the first appetible and the first intelligible are placed in the order of intelligible substances, and not in the order of sensible things, because it is the universal good, and consequently an immaterial substance, it is necessary that, through union with it, the substance that appetes and desires it be actually understanding: for something becomes actually understanding by being united to the intelligible. Hence, just as Plato held that our intellect becomes actually understanding through contact with and participation in the separate species, so too the intellect of the first mobile, according to Aristotle, becomes actually understanding through a certain contact with the first intelligible substance. And because that for the sake of which a thing is such is itself such to a greater degree, it follows that the intelligible itself is much more intellective, since to be intellective signifies a certain perfection. — But it is not the same with material things. For they are not actually intelligible in themselves; rather, they are made actually intelligible by the agent intellect. Therefore, from contact with those things themselves the intellect does not become actually understanding, but from the reception of species illuminated by the light of the agent intellect. Nor, however, is it necessary that those species be intellective, because they are not substances but accidents.

It is said, therefore, that this argument is a good one in Aristotle and Saint Thomas, and by the same reasoning it is denied that material things must be intelligent. And when it is proved on the grounds that man is actually intelligent through them, this is denied with respect to their natural esse: for they are not intelligible in act but only in potency. Hence the foundation of the argument is: That substance which is in itself actually intelligible, and which through union with it a desiring subject becomes actually intelligent, is intellective—since it ought not to be of lesser perfection than the substance perfected through it. But the first desirable object is of this kind. Therefore.

Note, however, that union is not taken here as belonging to the intelligible substance itself by way of a likeness that would be an accident, but rather through a certain participation of the substance on the part of the intellect.

X. Second ²⁸. The first unmoved mover is the universal principle of motion. Therefore the form by which it moves is universal, and a universal good. Therefore God is intellective. — The first consequence is proved: since every mover moves by means of some form which it intends in moving, the universal mover must move by means of a universal form. — The second is also proved: because a form in the mode of universality exists only in an intellect.

Note that the foundation of this argument is that, since the order of effects corresponds to the order of causes, as is said in II Phys. ²⁹ and V Metaph. ³⁰, therefore it must be that the form which the universal agent and mover intends first and principally be universal: that is, the formal ratio of the effect of that cause, insofar as it is its effect, must be a universal ratio. And since a form cannot have universal esse except in the intellect, therefore it must be that the very universal agent is intellective.

2. But this argument seems not to conclude. For in order that an agent intend a universal form, it is not necessary that the form itself have universal esse in the agent; it suffices that the effect correspond to it under that universal aspect: just as the heavens are a universal agent, and yet do not have in themselves a form according to universal esse. So, although God is a universal agent and intends a universal good, it is nevertheless not necessary that He have a universal form in Himself. And thus it is not necessary that, on account of the universality of the form, He have intellect.

For the understanding of this, it must be considered that, since—as we adduced in the preceding argument concerning the mind of Saint Thomas ³¹—the ratio of acting must be present in some way in the agent, it is necessary that an agent intending a universal form possess that universal form in itself in some way. But just as there is a twofold universal agent—namely according to predication, as when we say that animal generates animal, and according to perfection, as the heavens—so too must the universal form exist in a twofold way in a universal cause. For in a universal cause according to predication, it suffices that the universal form be actual in such a way that it has particular esse, while having universal esse potentially and fundamentally: because in the effect also it has particular esse, and the universal is intended by the particular agent only per accidens, or secondarily, namely insofar as the ratio of the universal is preserved in the particular; just as the particular itself is the agent first and per se, while the universal is so secondarily, insofar as it has esse in the particular. But in a universal cause according to perfection, since it intends the universal first and per se, and particulars secondarily, so that from them a universal good results, therefore it is necessary that in it the form by which it acts have universal esse; and consequently that cause itself be intellective, since only in intellect does form have universal esse.

But what is urged concerning the heavens is answered as follows: it is said that the heaven, if it is not animate, is an instrumental agent of the intelligence that moves it, and not a particular agent of the kind we are speaking of here, as is said in book three, chapter XXIV. And therefore there need not be in it a form according to universal esse, but only in the moving intelligence. But if it is posited as animate, then it is a principal agent, and has in itself a form according to universal esse through intellect.

XI. Third. Agents that move through intellect are compared to God as an instrument to the principal agent. Therefore God is an intelligent being. — The antecedent is evident, because all moving things that are in the world are compared to God in that way, since He is the first mover. — The consequence is proved, because in no order of movers is it found that a mover acting through intellect is the instrument of one that moves without intellect, but rather the reverse.

Fourth ³². God is altogether immaterial. Therefore He is intelligent. — The consequence is proved: because things become actually understood insofar as they are abstracted from matter. Hence also the intellect is of universals, not of particulars, because universals are abstracted from matter, which is the principle of individuation. But forms actually understood become one with the understanding intellect. Therefore, if forms are actually understood because they are without matter, some thing must be intelligent because it is without matter.

XIII. For the declaration of this proposition, Forms understood in act become one with the one understanding in act, note that, according to Saint Thomas, I Sent., d. xxxv, a. 1, ad 3, a form understood in act is not said to become one with the intellect in act as though it became the substance, or a part of the substance, of the possible intellect; but because it becomes the form of the intellect, and from their conjunction there comes to be that one thing which is the intellect in act; just as from soul and body there comes to be that one thing which is man, having human operations, and yet the soul does not become the body. This comparison, however, is not to be understood by way of similitude in all respects, but only in respect of this, that from them there comes to be one thing for operation: although perhaps from soul and body there comes to be one thing distinct from all the parts taken together, but not so from the intellect and the intelligible, just as neither from the substance of fire and its heat.

2. But this raises more doubt: how not only do the agent and the one understanding become one out of the intellect and the intelligible, but also how the intellect itself becomes the very intelligible thing; according to what is said in Book III of the Soul ³³, that the possible intellect is that by which all things become.

For the clarification of this, however, it must be considered that by "the thing understood in act" we can understand two things: namely, either the intelligible species itself, which is said to be understood in act not because it is the thing that is first and directly understood, but because it is that by which the thing represented through it is understood; or the thing itself which is first represented through that species.

In the first way, it is not properly said, nor is it Aristotle's meaning, that intellect in act is the thing understood in act; but it is well and truly said that it becomes one with that thing, inasmuch as from those two united there comes to be this one thing which is intellect in act. And thus they are in some way one: just as a whole is in some way one with its part, inasmuch as the part is not wholly extrinsic to the whole.

In the second way, however, it is true that they are the same, and that one becomes the other. For knowledge of this, it must be known that the form received in the intellect is the same form as that which exists outside the intellect according to its nature, but has a different esse: for outside the intellect it has natural esse, while in the intellect it has intelligible esse, as is clear from St. Thomas, Quodlibet VIII, q. 4. And the nature itself, as an existing perfection of a thing existing outside the intellect, is received into the intellect, as is St. Thomas's mind in De Veritate, q. 2, a. 2; on account of which it is said that such a nature, say a stone, perfects the intellect. But since each thing is what it is by its form and its nature, it follows that the intellect in act, which is an intellect in act insofar as it has the form and nature of the thing understood, is itself the thing understood: for one understanding a stone is a stone, just as one having in himself the form of a stone is a stone. Yet because the form of the stone does not have natural esse in the intellect—from which it would have something by which it might be called absolutely a stone—but intelligible esse, the intellect in act with respect to the stone is not called absolutely a stone, but is a stone intelligibly. This, then, is the manner in which the intellect, informed by the species of something understood, is said to be that very thing understood: namely, because it has its form, by which it is such.

By the same reasoning, the intellect itself is understood in act: namely, because it is understood in act by the same form by which the intellect itself is an intellect in act; for through the intelligible species existing in the intellect, by which the intellect is said to be an intellect in act, the thing is said to be understood in act.

For this reason the Commentator said, in III de Anima, comment. 5 ³⁴, that intellect and the intelligible become one more than matter and form do. And he assigns the reason: because nothing other than them comes to be from them, as happens in composites of matter and form. Explaining this in XII Metaph., comm. 39, he says that when it is understood, the intelligible becomes one with the intellect; and that the intellect is that which is understood; and for this reason it is said that the intellect is the thing understood—whereas matter does not become form, but some third thing comes to be from them—it is evident that intellect and the intelligible become one more than matter and form do.

What was said of the intellect must also be said of sense. For even the form existing in sense, by which sense is made actual, and the form of the sensible thing are one, distinguished only according to diverse modes of being. Hence, just as the Philosopher says of the intellect that intellect in act is the thing understood in act, and conversely, so too of sense, in Book II of the Soul ³⁵, he says that sense in act is the sensible in act, and the sensible in act is sense in act.

XIV. Concerning that inference, Forms understood in act become one with the one understanding in act. Therefore, if forms are understood in act because they are abstracted from matter, some thing must be understanding by the very fact that it is abstracted from matter, a doubt is raised. It indeed seems to follow that the intellect must be immaterial, from the fact that, in order for something to be understood in act, it must be abstracted from matter; yet not that it is understanding in virtue of its immateriality, as if everything lacking matter were understanding.

To make this evident, it must be understood that this argument of St. Thomas proceeds from a sign, as he himself says: that something must be abstracted from matter in order to be united to the intellect and to make one with it is a sign from this that whatever understands lacks matter. Now we can understand this as follows. For the intelligible in potency, by becoming intelligible in act, is drawn up into a certain higher order, which is called the order of intelligibles, in which order both intelligences and intelligibles are included; and the understanding thing becomes the very intelligible thing, just as what has a quiddity is in some way the quiddity itself; and the intelligible becomes the very understanding thing, just as the quiddity is in some way the very thing having the quiddity. But that one thing be drawn up into a higher order happens only because it takes on the condition from which it has something adequate so as to be in that order. And if it is drawn up so as to be identical with something of that order, it must be raised to the mode of that from which that thing has its being such: thus, if something must be raised up so as to become a man, it is necessary that it become a rational animal, from which man has what makes him a man; so that one thing becomes another precisely for the same cause for which that other is itself. If, therefore, by abstraction from matter something is drawn up into the order of intelligibles, namely so as to be an intellect in act, and by this becomes one with the understanding thing, so that the understanding thing is also the very intelligible thing, then necessarily abstraction from matter is the adequate condition of the order of the intelligible and of the understanding: otherwise that which is separated from matter would not precisely on this account be drawn up into the order of intelligibles and made identical with the understanding thing. From this it follows that everything which is in itself actually intelligible is also intellective: because abstraction from matter is the reason of both, namely both that something is actually intelligible and that it understands — unless there is in it something repugnant to intellection. I say this on account of spiritual accidents, which are indeed actually intelligible on account of their separation from matter, but are not intellective, because intellective esse is suited to belong only to substances. Therefore, when it is said that immateriality is the reason why something is of intellectual nature, this is understood in subsistent substances: for to operate belongs only to a subsistent.

It is therefore evident that the argument of St. Thomas is most sound and subtle. And from the fact that the intellect in act becomes one with the one understanding, it follows from the sign that, if it is such in act through abstraction from matter, not only is the one understanding immaterial, but also that it is from this that the one understanding is what it is, namely lacking matter.

XV. Fifth ³⁶. The most excellent of perfections is that something be intellectual: since by this it is in a way all things, possessing the perfections of all things within itself. Therefore God is intellectual. — The consequence is evident. Because no perfection is lacking to God among those which do not posit composition in God.

Note here, from the doctrine of Saint Thomas in the First Part, q. xiv ³⁷, and Verit., q. ii ³⁸, that since each thing is determined to the degree of its own nature and perfection, knowing things have this proper to them: that they can also possess the natures and perfections of other things, while they are informed by likenesses of other things in order to know them. And thus the intellect, which is cognitive of all things, is receptive of all things and is in a certain way all things, while it is informed by the likenesses of all things: so that, if it is a possible intellect, before it is informed by the likenesses of things, those things are in it in potency; but when it is informed in act, those things are said to be in it in act.

It must be considered, however, that although even non-cognitive things receive within themselves the natures of other things, this occurs differently than in cognitive natures. For those things do not receive the substantial essences of other things, but only their accidents. Likewise, they receive accidents according to some natural esse of their own. Moreover, the perfection of another thing is not in them as an existing perfection of that other thing, but only as their own perfection. In a cognizing being, however, especially an intellective one, there are naturally present not only the essences of accidents but also of substances. Similarly, these are not received in it according to natural esse, but according to intentional esse. Nor are they received as perfections existing only in the intellect, but as existing perfections of extrinsic things: just as the nature and perfection of a stone, as an existing perfection of the stone, is received in the intellect; for the likeness of the stone in the soul is the very nature of the stone which exists outside the soul, but in intelligible esse. And this is proper to a cognizing being: that it receive within itself, immaterially, the perfection of another thing as an existing perfection of that other.

2. From these things the solution of a certain objection that could be raised against this proposition is evident—a proposition which St. Thomas states explicitly in the First Part, q. 14, a. 1, but which is stated here implicitly, namely: Only cognizing beings are naturally fitted to have within themselves the form of another thing. For if we speak with respect to the natural esse of things, it is clear that even non-cognizing things receive the forms of other things: for water receives heat, and a wall whiteness. But if we speak with respect to intentional esse, it is clear that in the air there is received the species of the white and the black, and of sound and of other sensible things.

But it is clear from what has been said that there is no objection. First, because the proposition of St. Thomas is understood of subsistent forms and natures, not of accidental forms. Now it is evident that a non-cognizing substance does not receive into itself the natures of other substances, but a cognizing substance does so well. — Second, because, although in air the form of white is received according to intentional esse, it is nevertheless not received in air as a perfection existing of white, but only as a perfection in some way of air. In sense and intellect, however, as was said, the nature of the thing known is received intentionally as it is a perfection of the thing known itself: whence the knower has it that it knows the very thing.

It may also be said that it is proper to cognitive natures to receive the forms of other things for their own sake, that is, on account of their own perfection, namely, so that their own operation may be perfect. But this does not belong to air. For in air there is received the species of a colored thing so that it may carry it to the sense: not, however, so that the proper operation of air may receive its completion through such a species.

XVI. Sixth. God has appointed and determined an end for all natural things. Therefore He is intelligent. — The consequence is proved: because He could not appoint an end unless He understood. — But the antecedent is proved as follows. Natural things tend toward determinate ends, since the benefits of nature do not arise by chance, but always or for the most part. Therefore either they appoint an end to themselves, or it is determined and appointed for them by another. But they do not appoint an end to themselves, since they do not know the reason of the end. Therefore it is appointed for them by another, who is the creator of their nature. And Him we call God. Therefore, etc.

Note here that to set an end for oneself is to establish for oneself something toward which one's own operations are directed: just as an archer sets for himself a target toward which he wishes to direct his arrow. Now this cannot belong except to one who knows both the end, and what the end is, and that something has the character of an end; for nothing can be set up as an end except by one who knows and apprehends what it is to be an end, namely because it is the last thing toward which works are directed. Natural agents, however, although they proceed in an orderly way in their operations, because they are directed by some intellect, nevertheless do not know the end itself, and much less the character of an end and its quiddity. Brute animals, however, although they know materially that which is the end of their operations, do not know it formally under the aspect of an end. Hence they too do not know the character of an end; and consequently neither do they set an end for themselves. Since, therefore, two things are required in order that something may set and determine an end for itself—namely, that it know the end and the character of an end—the knowledge of the character of an end is what is principally required. Therefore Saint Thomas assigned this as the cause here, a point in which natural things agree with brute animals, and from which it belongs to them not to set an end for themselves.

XVII. Seventh. God is the first subsistent act, on which all things depend. Therefore He is intelligent. — The consequence is proved. The forms existing in things are imperfect: because they exist particulariter, and not according to the community of their rational character. Therefore they must be derived from forms that are not subject to particularity, since the imperfect is derived from something perfect. Therefore from intelligible forms, since a form is not found in its universality except in an intellect. Therefore from intelligent forms, if they are subsistent (for only thus can they be operative). Therefore, if God is the act on which all things depend, He must be intelligent.

It must be noted here that, as was shown above ³⁹, a form understood in act is understood in act precisely because it is separated from matter, and thus it has no limitation in the esse of its nature. Therefore a form understood, as such, has an esse more perfect than that same form existing particularly in a thing, which, from the fact that it has esse in something receptive, is limited with respect to the esse befitting its nature. But since from the same cause, as we have said—namely, from immateriality—it comes about that something is both understood and understanding, if it subsists, Saint Thomas rightly concludes that that form having universal and unlimited esse must also be intelligent.

Note further that when St. Thomas says that forms are not in particular things according to the community of their ratio, this can have a twofold sense. One is that in particular things forms are not present according to all that pertains to their essential ratio. And this sense is false, and is not what is intended here. For if a nature existing particularly in a thing were not in the thing according to its whole ratio, the thing would not be said to be essentially such: for Socrates would not be essentially a man if the whole quiddity of man were not preserved in him. — The other sense is that that ratio is not in the thing according to unlimited esse. And this sense is true, and is what is intended. For although man is in Socrates according to his whole ratio, yet that ratio does not have in him its community and unlimitedness, but only insofar as it is in the intellect.

But it must be noted that the form which has unlimited esse in the intellect, which is also called a form understood in act, is sometimes not subsistent but an accident of the intellect. And then a natural thing does not depend on such a form as on an agent, as happens with the form that is in our intellect: for to operate belongs to a subsisting thing. Sometimes, however, it is subsistent, as the form that is in the divine intellect: for the stone existing immaterially in the divine intellect is not an accident of the divine intellect, but subsists and is the very divine substance. Therefore there belongs to it the character of producing that form itself according to its particular and limited esse in things. Hence it does not follow simply that a form having particular esse depends upon it insofar as it has understood esse, but with this addition, that it subsist: for then that esse is in every way more perfect, since it is subsistent esse, unlimited and infinite in its nature—indeed, in God simply infinite.

It is confirmed lastly by the authorities of Scripture, Job ix and xii, and the Psalms, and Romans xi. — Also from the imposition of the name. For this word theos, which among the Greeks signifies God, is said to derive from theasthe, which means to consider or to see.