Thomas Aquinas, Disputed Questions on Truth (De Veritate)

1. The mover is naturally prior to the thing moved. But the will is posterior to the intellect, for nothing is loved or desired unless it is known, according to Augustine. The will therefore does not move the intellect.

2. If the will moves the intellect to its act, then it follows that the intellect understands because the will wants it to understand. But the will does not want anything unless it is understood. The intellect therefore first understands its understanding before the will wills it. But before the intellect could understand this, the will would have to be held to will it, because the intellect is held to be moved by the will. We should then have to go on to infinity. But this is impossible. Therefore the will does not move the intellect.

3. Every passive power is moved by its object. But the will is a passive power, for appetite is a mover which is moved, as is said in The Soul. Hence it is moved by its object. But its object is the understood or apprehended good, as is said in the same book. Therefore the intellect or some other apprehensive power moves the will, and not the other way about.

4. One power is said to move another only because of the ability to command which it has over the other. But to command belongs to reason, as is said in the Ethics. It therefore belongs to reason to command the other powers and not to the will.

5. According to Augustine the mover and agent is nobler than the thing moved or made. But the intellect is nobler than the will, at least in regard to sensible things, as has been explained. At least in regard to these, then, it is not moved by the will.

To the Contrary:

1'. Anselm says that the will moves all the other powers of the soul.

2'. According to Augustine every motion proceeds from what is immovable. But among the powers of the soul the will is the only one which is immovable in the sense of not being able to be forced by anything. All the other powers of the soul are therefore moved by the will.

3'. According to the Philosopher every motion occurs for the sake of an end. But good and the end are the object of the will. The will, then, moves the other powers.

4'. According to Augustine, among spirits love does the same thing as weight among bodies. But weight moves bodies. Then the love of the will moves the spiritual powers of the soul.

REPLY:

In a way the intellect moves the will, and in a way the will moves the intellect and the other powers. For the clarification of this it should be noted that both an end and an efficient cause are said to move, but in different ways. Two things are to be taken into account in any action, the agent and the reason for acting. In heating, the agent is fire and the reason for acting is heat. Similarly in moving, the end is said to move as the reason for moving, but the efficient cause, as the one producing the movement, that is, the one which brings the subject of the motion from potency to act.

The reason for acting is the form of the agent by which it acts. It must accordingly be in the agent for it to act. It is not there, however, according to its perfect act of being; for when that is had the motion comes to rest. But it is in the agent by way of an intention, for the end is prior in intention but posterior in being. Thus the end preexists in the mover in a proper sense intellectually (for it belongs to intellect to receive something by way of an intention) and not according to its real existence. Hence the intellect moves the will in the way in which an end is said to move--by conceiving beforehand the reason for acting and proposing it to the will.

To move in the manner of an efficient cause, however, belongs to the will and not to the intellect; for the will is referred to things as they are in themselves, whereas the intellect is referred to them as existing spiritually in the soul. Now to act and to move pertain to things according to their own act of being by which they subsist in themselves, not according as they exist in the soul in the manner of an intention. It is not heat in the soul which heats, but that which is in fire. Thus the will is referred to things as subject to motion, but not the intellect. Furthermore the act of the will is an inclination to something, but not that of the intellect. But an inclination is the disposition of something that moves other things as an efficient cause moves. It is accordingly evident that the will has the function of moving in the manner of an agent cause; not, however, the intellect.

The higher powers of the soul, because immaterial, are capable of reflecting upon themselves. Both the will and the intellect, therefore, reflect upon themselves, upon each other, upon the essence of the soul, and upon all its powers. The intellect understands itself and the will and the essence of the soul and all the soul's powers. Similarly the will wills that it will, that the intellect understand, that the soul be, and so of the other powers. Now when one power is brought to bear upon another, it is referred to that other according to what is proper to itself. When the intellect understands that the will is willing, it receives within itself the intelligible character of willing. When the will is brought to bear upon the other powers of the soul, it is directed to them as things to which motion and operation belong, and it inclines each to its own operation. Thus the will moves in the manner of an efficient cause not only external things but also the very powers of the soul.

Answers to Difficulties:

1. Since there is in reflection a certain similarity to circular motion, in which what is last is the same as what was originally the beginning, we must so express ourselves in regard to reflection that what was originally prior then becomes posterior. And so, although the intellect is prior to the will when taken absolutely, it nonetheless becomes posterior to the will by reflection. Thus the will can move the intellect.

2. There is no necessity of going on to infinity, for we stop at the natural appetite by which the intellect is inclined to its act.

3. The argument shows that the intellect moves in the manner of an end, for this is the bearing of the apprehended good upon the will.

4. Command belongs to both will and reason but in different respects. It belongs to the will in so far as a command implies an inclination; it belongs to reason in so far as this inclination is distributed and ordained to be carried out by this or that individual.

5. Any power surpasses another in what is proper to itself. Thus touch is referred to heat, which it senses in itself, in a more perfect way than sight, which sees it only by accident. Similarly the intellect is referred to truth more completely than the will; and conversely, the will is referred to the good in things more perfectly than the intellect. Hence, although the intellect is nobler than the will absolutely, at least in regard to some things, nevertheless under the aspect of moving, which belongs to the will by reason of the distinctive characteristic of its object, the will is found to be nobler.