Summa Theologica

We now inquire concerning free-will. Under this head there are four points of inquiry:

(1) Whether man has free-will?

(2) What is free-will—a power, an act, or a habit?

(3) If it is a power, is it appetitive or cognitive?

(4) If it is appetitive, is it the same power as the will, or distinct?

Objection 1: It would seem that man has not free-will. For whoever has free-will does what he wills. But man does not what he wills; for it is written (Rom. 7:19): "For the good which I will I do not, but the evil which I will not, that I do." Therefore man has not free-will.

Objection 2: Further, whoever has free-will has in his power to will or not to will, to do or not to do. But this is not in man's power: for it is written (Rom. 9:16): "It is not of him that willeth"—namely, to will—"nor of him that runneth"—namely, to run. Therefore man has not free-will.

Objection 3: Further, what is "free is cause of itself," as the Philosopher says (Metaph. i, 2). Therefore what is moved by another is not free. But God moves the will, for it is written (Prov. 21:1): "The heart of the king is in the hand of the Lord; whithersoever He will He shall turn it" and (Phil. 2:13): "It is God Who worketh in you both to will and to accomplish." Therefore man has not free-will.

Objection 4: Further, whoever has free-will is master of his own actions. But man is not master of his own actions: for it is written (Jer. 10:23): "The way of a man is not his: neither is it in a man to walk." Therefore man has not free-will.

Objection 5: Further, the Philosopher says (Ethic. iii, 5): "According as each one is, such does the end seem to him." But it is not in our power to be of one quality or another; for this comes to us from nature. Therefore it is natural to us to follow some particular end, and therefore we are not free in so doing.

On the contrary, It is written (Ecclus. 15:14): "God made man from the beginning, and left him in the hand of his own counsel"; and the gloss adds: "That is of his free-will."

I answer that, Man has free-will: otherwise counsels, exhortations, commands, prohibitions, rewards, and punishments would be in vain. In order to make this evident, we must observe that some things act without judgment; as a stone moves downwards; and in like manner all things which lack knowledge. And some act from judgment, but not a free judgment; as brute animals. For the sheep, seeing the wolf, judges it a thing to be shunned, from a natural and not a free judgment, because it judges, not from reason, but from natural instinct. And the same thing is to be said of any judgment of brute animals. But man acts from judgment, because by his apprehensive power he judges that something should be avoided or sought. But because this judgment, in the case of some particular act, is not from a natural instinct, but from some act of comparison in the reason, therefore he acts from free judgment and retains the power of being inclined to various things. For reason in contingent matters may follow opposite courses, as we see in dialectic syllogisms and rhetorical arguments. Now particular operations are contingent, and therefore in such matters the judgment of reason may follow opposite courses, and is not determinate to one. And forasmuch as man is rational is it necessary that man have a free-will.

Reply to Objection 1: As we have said above (Q[81], A[3], ad 2), the sensitive appetite, though it obeys the reason, yet in a given case can resist by desiring what the reason forbids. This is therefore the good which man does not when he wishes—namely, "not to desire against reason," as Augustine says.

Reply to Objection 2: Those words of the Apostle are not to be taken as though man does not wish or does not run of his free-will, but because the free-will is not sufficient thereto unless it be moved and helped by God.

Reply to Objection 3: Free-will is the cause of its own movement, because by his free-will man moves himself to act. But it does not of necessity belong to liberty that what is free should be the first cause of itself, as neither for one thing to be cause of another need it be the first cause. God, therefore, is the first cause, Who moves causes both natural and voluntary. And just as by moving natural causes He does not prevent their acts being natural, so by moving voluntary causes He does not deprive their actions of being voluntary: but rather is He the cause of this very thing in them; for He operates in each thing according to its own nature.

Reply to Objection 4: "Man's way" is said "not to be his" in the execution of his choice, wherein he may be impeded, whether he will or not. The choice itself, however, is in us, but presupposes the help of God.

Reply to Objection 5: Quality in man is of two kinds: natural and adventitious. Now the natural quality may be in the intellectual part, or in the body and its powers. From the very fact, therefore, that man is such by virtue of a natural quality which is in the intellectual part, he naturally desires his last end, which is happiness. Which desire, indeed, is a natural desire, and is not subject to free-will, as is clear from what we have said above (Q[82], AA,2). But on the part of the body and its powers man may be such by virtue of a natural quality, inasmuch as he is of such a temperament or disposition due to any impression whatever produced by corporeal causes, which cannot affect the intellectual part, since it is not the act of a corporeal organ. And such as a man is by virtue of a corporeal quality, such also does his end seem to him, because from such a disposition a man is inclined to choose or reject something. But these inclinations are subject to the judgment of reason, which the lower appetite obeys, as we have said (Q[81], A[3]). Wherefore this is in no way prejudicial to free-will.

The adventitious qualities are habits and passions, by virtue of which a man is inclined to one thing rather than to another. And yet even these inclinations are subject to the judgment of reason. Such qualities, too, are subject to reason, as it is in our power either to acquire them, whether by causing them or disposing ourselves to them, or to reject them. And so there is nothing in this that is repugnant to free-will.

Objection 1: It would seem that free-will is not a power. For free-will is nothing but a free judgment. But judgment denominates an act, not a power. Therefore free-will is not a power.

Objection 2: Further, free-will is defined as "the faculty of the will and reason." But faculty denominates a facility of power, which is due to a habit. Therefore free-will is a habit. Moreover Bernard says (De Gratia et Lib. Arb. 1,2) that free-will is "the soul's habit of disposing of itself." Therefore it is not a power.

Objection 3: Further, no natural power is forfeited through sin. But free-will is forfeited through sin; for Augustine says that "man, by abusing free-will, loses both it and himself." Therefore free-will is not a power.

On the contrary, Nothing but a power, seemingly, is the subject of a habit. But free-will is the subject of grace, by the help of which it chooses what is good. Therefore free-will is a power.

I answer that, Although free-will [*Liberum arbitrium—i.e. free judgment] in its strict sense denotes an act, in the common manner of speaking we call free-will, that which is the principle of the act by which man judges freely. Now in us the principle of an act is both power and habit; for we say that we know something both by knowledge and by the intellectual power. Therefore free-will must be either a power or a habit, or a power with a habit. That it is neither a habit nor a power together with a habit, can be clearly proved in two ways. First of all, because, if it is a habit, it must be a natural habit; for it is natural to man to have a free-will. But there is not natural habit in us with respect to those things which come under free-will: for we are naturally inclined to those things of which we have natural habits—for instance, to assent to first principles: while those things which we are naturally inclined are not subject to free-will, as we have said of the desire of happiness (Q[82], AA,2). Wherefore it is against the very notion of free-will that it should be a natural habit. And that it should be a non-natural habit is against its nature. Therefore in no sense is it a habit.

Secondly, this is clear because habits are defined as that "by reason of which we are well or ill disposed with regard to actions and passions" (Ethic. ii, 5); for by temperance we are well-disposed as regards concupiscences, and by intemperance ill-disposed: and by knowledge we are well-disposed to the act of the intellect when we know the truth, and by the contrary ill-disposed. But the free-will is indifferent to good and evil choice: wherefore it is impossible for free-will to be a habit. Therefore it is a power.

Reply to Objection 1: It is not unusual for a power to be named from its act. And so from this act, which is a free judgment, is named the power which is the principle of this act. Otherwise, if free-will denominated an act, it would not always remain in man.

Reply to Objection 2: Faculty sometimes denominates a power ready for operation, and in this sense faculty is used in the definition of free-will. But Bernard takes habit, not as divided against power, but as signifying a certain aptitude by which a man has some sort of relation to an act. And this may be both by a power and by a habit: for by a power man is, as it were, empowered to do the action, and by the habit he is apt to act well or ill.

Reply to Objection 3: Man is said to have lost free-will by falling into sin, not as to natural liberty, which is freedom from coercion, but as regards freedom from fault and unhappiness. Of this we shall treat later in the treatise on Morals in the second part of this work (FS, Q[85], seqq.; Q[109]).

Objection 1: It would seem that free-will is not an appetitive, but a cognitive power. For Damascene (De Fide Orth. ii, 27) says that "free-will straightway accompanies the rational nature." But reason is a cognitive power. Therefore free-will is a cognitive power.

Objection 2: Further, free-will is so called as though it were a free judgment. But to judge is an act of a cognitive power. Therefore free-will is a cognitive power.

Objection 3: Further, the principal function of free-will is to choose. But choice seems to belong to knowledge, because it implies a certain comparison of one thing to another, which belongs to the cognitive power. Therefore free-will is a cognitive power.

On the contrary, The Philosopher says (Ethic. iii, 3) that choice is "the desire of those things which are in us." But desire is an act of the appetitive power: therefore choice is also. But free-will is that by which we choose. Therefore free-will is an appetitive power.

I answer that, The proper act of free-will is choice: for we say that we have a free-will because we can take one thing while refusing another; and this is to choose. Therefore we must consider the nature of free-will, by considering the nature of choice. Now two things concur in choice: one on the part of the cognitive power, the other on the part of the appetitive power. On the part of the cognitive power, counsel is required, by which we judge one thing to be preferred to another: and on the part of the appetitive power, it is required that the appetite should accept the judgment of counsel. Therefore Aristotle (Ethic. vi, 2) leaves it in doubt whether choice belongs principally to the appetitive or the cognitive power: since he says that choice is either "an appetitive intellect or an intellectual appetite." But (Ethic. iii, 3) he inclines to its being an intellectual appetite when he describes choice as "a desire proceeding from counsel." And the reason of this is because the proper object of choice is the means to the end: and this, as such, is in the nature of that good which is called useful: wherefore since good, as such, is the object of the appetite, it follows that choice is principally an act of the appetitive power. And thus free-will is an appetitive power.

Reply to Objection 1: The appetitive powers accompany the apprehensive, and in this sense Damascene says that free-will straightway accompanies the rational power.

Reply to Objection 2: Judgment, as it were, concludes and terminates counsel. Now counsel is terminated, first, by the judgment of reason; secondly, by the acceptation of the appetite: whence the Philosopher (Ethic. iii, 3) says that, "having formed a judgment by counsel, we desire in accordance with that counsel." And in this sense choice itself is a judgment from which free-will takes its name.

Reply to Objection 3: This comparison which is implied in the choice belongs to the preceding counsel, which is an act of reason. For though the appetite does not make comparisons, yet forasmuch as it is moved by the apprehensive power which does compare, it has some likeness of comparison by choosing one in preference to another.

Objection 1: It would seem that free-will is a power distinct from the will. For Damascene says (De Fide Orth. ii, 22) that {thelesis} is one thing and {boulesis} another. But {thelesis} is the will, while {boulesis} seems to be the free-will, because {boulesis}, according to him, is will as concerning an object by way of comparison between two things. Therefore it seems that free-will is a distinct power from the will.

Objection 2: Further, powers are known by their acts. But choice, which is the act of free-will, is distinct from the act of willing, because "the act of the will regards the end, whereas choice regards the means to the end" (Ethic. iii, 2). Therefore free-will is a distinct power from the will.

Objection 3: Further, the will is the intellectual appetite. But in the intellect there are two powers—the active and the passive. Therefore, also on the part of the intellectual appetite, there must be another power besides the will. And this, seemingly, can only be free-will. Therefore free-will is a distinct power from the will.

On the contrary, Damascene says (De Fide Orth. iii, 14) free-will is nothing else than the will.

I answer that, The appetitive powers must be proportionate to the apprehensive powers, as we have said above (Q[64], A[2]). Now, as on the part of the intellectual apprehension we have intellect and reason, so on the part of the intellectual appetite we have will, and free-will which is nothing else but the power of choice. And this is clear from their relations to their respective objects and acts. For the act of "understanding" implies the simple acceptation of something; whence we say that we understand first principles, which are known of themselves without any comparison. But to "reason," properly speaking, is to come from one thing to the knowledge of another: wherefore, properly speaking, we reason about conclusions, which are known from the principles. In like manner on the part of the appetite to "will" implies the simple appetite for something: wherefore the will is said to regard the end, which is desired for itself. But to "choose" is to desire something for the sake of obtaining something else: wherefore, properly speaking, it regards the means to the end. Now, in matters of knowledge, the principles are related to the conclusion to which we assent on account of the principles: just as, in appetitive matters, the end is related to the means, which is desired on account of the end. Wherefore it is evident that as the intellect is to reason, so is the will to the power of choice, which is free-will. But it has been shown above (Q[79], A[8]) that it belongs to the same power both to understand and to reason, even as it belongs to the same power to be at rest and to be in movement. Wherefore it belongs also to the same power to will and to choose: and on this account the will and the free-will are not two powers, but one.

Reply to Objection 1: {Boulesis} is distinct from {thelesis} on account of a distinction, not of powers, but of acts.

Reply to Objection 2: Choice and will—that is, the act of willing —are different acts: yet they belong to the same power, as also to understand and to reason, as we have said.

Reply to Objection 3: The intellect is compared to the will as moving the will. And therefore there is no need to distinguish in the will an active and a passive will.

HOW THE SOUL WHILE UNITED TO THE BODY UNDERSTANDS CORPOREAL THINGS BENEATH IT (EIGHT ARTICLES)

We now have to consider the acts of the soul in regard to the intellectual and the appetitive powers: for the other powers of the soul do not come directly under the consideration of the theologian. Furthermore, the acts of the appetitive part of the soul come under the consideration of the science of morals; wherefore we shall treat of them in the second part of this work, to which the consideration of moral matters belongs. But of the acts of the intellectual part we shall treat now.

In treating of these acts we shall proceed in the following order: First, we shall inquire how the soul understands when united to the body; secondly, how it understands when separated therefrom.

The former of these inquiries will be threefold: (1) How the soul understands bodies which are beneath it; (2) How it understands itself and things contained in itself; (3) How it understands immaterial substances, which are above it.

In treating of the knowledge of corporeal things there are three points to be considered: (1) Through what does the soul know them? (2) How and in what order does it know them? (3) What does it know in them?

Under the first head there are eight points of inquiry:

(1) Whether the soul knows bodies through the intellect?

(2) Whether it understands them through its essence, or through any species?

(3) If through some species, whether the species of all things intelligible are naturally innate in the soul?

(4) Whether these species are derived by the soul from certain separate immaterial forms?

(5) Whether our soul sees in the eternal ideas all that it understands?

(6) Whether it acquires intellectual knowledge from the senses?

(7) Whether the intellect can, through the species of which it is possessed, actually understand, without turning to the phantasms?

(8) Whether the judgment of the intellect is hindered by an obstacle in the sensitive powers?

Objection 1: It would seem that the soul does not know bodies through the intellect. For Augustine says (Soliloq. ii, 4) that "bodies cannot be understood by the intellect; nor indeed anything corporeal unless it can be perceived by the senses." He says also (Gen. ad lit. xii, 24) that intellectual vision is of those things that are in the soul by their essence. But such are not bodies. Therefore the soul cannot know bodies through the intellect.

Objection 2: Further, as sense is to the intelligible, so is the intellect to the sensible. But the soul can by no means, through the senses, understand spiritual things, which are intelligible. Therefore by no means can it, through the intellect, know bodies, which are sensible.

Objection 3: Further, the intellect is concerned with things that are necessary and unchangeable. But all bodies are mobile and changeable. Therefore the soul cannot know bodies through the intellect.

On the contrary, Science is in the intellect. If, therefore, the intellect does not know bodies, it follows that there is no science of bodies; and thus perishes natural science, which treats of mobile bodies.

I answer that, It should be said in order to elucidate this question, that the early philosophers, who inquired into the natures of things, thought there was nothing in the world save bodies. And because they observed that all bodies are mobile, and considered them to be ever in a state of flux, they were of opinion that we can have no certain knowledge of the true nature of things. For what is in a continual state of flux, cannot be grasped with any degree of certitude, for it passes away ere the mind can form a judgment thereon: according to the saying of Heraclitus, that "it is not possible twice to touch a drop of water in a passing torrent," as the Philosopher relates (Metaph. iv, Did. iii, 5).

After these came Plato, who, wishing to save the certitude of our knowledge of truth through the intellect, maintained that, besides these things corporeal, there is another genus of beings, separate from matter and movement, which beings he called "species" or "ideas," by participation of which each one of these singular and sensible things is said to be either a man, or a horse, or the like. Wherefore he said that sciences and definitions, and whatever appertains to the act of the intellect, are not referred to these sensible bodies, but to those beings immaterial and separate: so that according to this the soul does not understand these corporeal things, but the separate species thereof.

Now this may be shown to be false for two reasons. First, because, since those species are immaterial and immovable, knowledge of movement and matter would be excluded from science (which knowledge is proper to natural science), and likewise all demonstration through moving and material causes. Secondly, because it seems ridiculous, when we seek for knowledge of things which are to us manifest, to introduce other beings, which cannot be the substance of those others, since they differ from them essentially: so that granted that we have a knowledge of those separate substances, we cannot for that reason claim to form a judgment concerning these sensible things.

Now it seems that Plato strayed from the truth because, having observed that all knowledge takes place through some kind of similitude, he thought that the form of the thing known must of necessity be in the knower in the same manner as in the thing known. Then he observed that the form of the thing understood is in the intellect under conditions of universality, immateriality, and immobility: which is apparent from the very operation of the intellect, whose act of understanding has a universal extension, and is subject to a certain amount of necessity: for the mode of action corresponds to the mode of the agent's form. Wherefore he concluded that the things which we understand must have in themselves an existence under the same conditions of immateriality and immobility.

But there is no necessity for this. For even in sensible things it is to be observed that the form is otherwise in one sensible than in another: for instance, whiteness may be of great intensity in one, and of a less intensity in another: in one we find whiteness with sweetness, in another without sweetness. In the same way the sensible form is conditioned differently in the thing which is external to the soul, and in the senses which receive the forms of sensible things without receiving matter, such as the color of gold without receiving gold. So also the intellect, according to its own mode, receives under conditions of immateriality and immobility, the species of material and mobile bodies: for the received is in the receiver according to the mode of the receiver. We must conclude, therefore, that through the intellect the soul knows bodies by a knowledge which is immaterial, universal, and necessary.

Reply to Objection 1: These words of Augustine are to be understood as referring to the medium of intellectual knowledge, and not to its object. For the intellect knows bodies by understanding them, not indeed through bodies, nor through material and corporeal species; but through immaterial and intelligible species, which can be in the soul by their own essence.

Reply to Objection 2: As Augustine says (De Civ. Dei xxii, 29), it is not correct to say that as the sense knows only bodies so the intellect knows only spiritual things; for it follows that God and the angels would not know corporeal things. The reason of this diversity is that the lower power does not extend to those things that belong to the higher power; whereas the higher power operates in a more excellent manner those things which belong to the lower power.

Reply to Objection 3: Every movement presupposes something immovable: for when a change of quality occurs, the substance remains unmoved; and when there is a change of substantial form, matter remains unmoved. Moreover the various conditions of mutable things are themselves immovable; for instance, though Socrates be not always sitting, yet it is an immovable truth that whenever he does sit he remains in one place. For this reason there is nothing to hinder our having an immovable science of movable things.

Objection 1: It would seem that the soul understands corporeal things through its essence. For Augustine says (De Trin. x, 5) that the soul "collects and lays hold of the images of bodies which are formed in the soul and of the soul: for in forming them it gives them something of its own substance." But the soul understands bodies by images of bodies. Therefore the soul knows bodies through its essence, which it employs for the formation of such images, and from which it forms them.

Objection 2: Further, the Philosopher says (De Anima iii, 8) that "the soul, after a fashion, is everything." Since, therefore, like is known by like, it seems that the soul knows corporeal things through itself.

Objection 3: Further, the soul is superior to corporeal creatures. Now lower things are in higher things in a more eminent way than in themselves, as Dionysius says (Coel. Hier. xii). Therefore all corporeal creatures exist in a more excellent way in the soul than in themselves. Therefore the soul can know corporeal creatures through its essence.

On the contrary, Augustine says (De Trin. ix, 3) that "the mind gathers knowledge of corporeal things through the bodily senses." But the soul itself cannot be known through the bodily senses. Therefore it does not know corporeal things through itself.

I answer that, The ancient philosophers held that the soul knows bodies through its essence. For it was universally admitted that "like is known by like." But they thought that the form of the thing known is in the knower in the same mode as in the thing known. The Platonists however were of a contrary opinion. For Plato, having observed that the intellectual soul has an immaterial nature, and an immaterial mode of knowledge, held that the forms of things known subsist immaterially. While the earlier natural philosophers, observing that things known are corporeal and material, held that things known must exist materially even in the soul that knows them. And therefore, in order to ascribe to the soul a knowledge of all things, they held that it has the same nature in common with all. And because the nature of a result is determined by its principles, they ascribed to the soul the nature of a principle; so that those who thought fire to be the principle of all, held that the soul had the nature of fire; and in like manner as to air and water. Lastly, Empedocles, who held the existence of our four material elements and two principles of movement, said that the soul was composed of these. Consequently, since they held that things exist in the soul materially, they maintained that all the soul's knowledge is material, thus failing to discern intellect from sense.

But this opinion will not hold. First, because in the material principle of which they spoke, the various results do not exist save in potentiality. But a thing is not known according as it is in potentiality, but only according as it is in act, as is shown Metaph. ix (Did. viii, 9): wherefore neither is a power known except through its act. It is therefore insufficient to ascribe to the soul the nature of the principles in order to explain the fact that it knows all, unless we further admit in the soul natures and forms of each individual result, for instance, of bone, flesh, and the like; thus does Aristotle argue against Empedocles (De Anima i, 5). Secondly, because if it were necessary for the thing known to exist materially in the knower, there would be no reason why things which have a material existence outside the soul should be devoid of knowledge; why, for instance, if by fire the soul knows fire, that fire also which is outside the soul should not have knowledge of fire.

We must conclude, therefore, that material things known must needs exist in the knower, not materially, but immaterially. The reason of this is, because the act of knowledge extends to things outside the knower: for we know things even that are external to us. Now by matter the form of a thing is determined to some one thing. Wherefore it is clear that knowledge is in inverse ratio of materiality. And consequently things that are not receptive of forms save materially, have no power of knowledge whatever—such as plants, as the Philosopher says (De Anima ii, 12). But the more immaterially a thing receives the form of the thing known, the more perfect is its knowledge. Therefore the intellect which abstracts the species not only from matter, but also from the individuating conditions of matter, has more perfect knowledge than the senses, which receive the form of the thing known, without matter indeed, but subject to material conditions. Moreover, among the senses, sight has the most perfect knowledge, because it is the least material, as we have remarked above (Q[78], A[3]): while among intellects the more perfect is the more immaterial.

It is therefore clear from the foregoing, that if there be an intellect which knows all things by its essence, then its essence must needs have all things in itself immaterially; thus the early philosophers held that the essence of the soul, that it may know all things, must be actually composed of the principles of all material things. Now this is proper to God, that His Essence comprise all things immaterially as effects pre-exist virtually in their cause. God alone, therefore, understands all things through His Essence: but neither the human soul nor the angels can do so.

Reply to Objection 1: Augustine in that passage is speaking of an imaginary vision, which takes place through the image of bodies. To the formation of such images the soul gives part of its substance, just as a subject is given in order to be informed by some form. In this way the soul makes such images from itself; not that the soul or some part of the soul be turned into this or that image; but just as we say that a body is made into something colored because of its being informed with color. That this is the sense, is clear from what follows. For he says that the soul "keeps something"—namely, not informed with such image—"which is able freely to judge of the species of these images": and that this is the "mind" or "intellect." And he says that the part which is informed with these images—namely, the imagination—is "common to us and beasts."

Reply to Objection 2: Aristotle did not hold that the soul is actually composed of all things, as did the earlier philosophers; he said that the soul is all things, "after a fashion," forasmuch as it is in potentiality to all—through the senses, to all things sensible—through the intellect, to all things intelligible.

Reply to Objection 3: Every creature has a finite and determinate essence. Wherefore although the essence of the higher creature has a certain likeness to the lower creature, forasmuch as they have something in common generically, yet it has not a complete likeness thereof, because it is determined to a certain species other than the species of the lower creature. But the Divine Essence is a perfect likeness of all, whatsoever may be found to exist in things created, being the universal principle of all.