Lecture 2 — Intellectual abstraction

But when it becomes particular objects as does a knower, one is then spoken of as in act. (This comes about as soon as such a one is able to act of himself.) It is, then, in a way still in potency, but not in the way it was before it learned or discovered. And then, too, it is able to understand its very self.

Now, as magnitude is one thing and the being of magnitude another, and as water is one thing and the being of water another, and so with many other things (but not all things, for in certain things flesh is the same as the being of flesh), accordingly it discerns either by something else or by the same power differently disposed. (Though Aquinas is able to offer an interpretation of the confusing parenthetical above, this passage could instead be translated as follows: “ . . . but not in all things, for in certain things they are the same; accordingly, flesh and being flesh are discerned either by some other power or by the same power differently disposed.”)

For flesh is not without matter; rather, like the snub, this exists in that. By the sensitive power, therefore, it judges the hot and the cold and the things a certain ratio of which is flesh. But it discerns the being of flesh by something else, either by a separate power or by it as if it were bent back upon itself (whereas it was straightened).

Again, in the things that exist by abstraction, the straight is as the snub; for it goes with the continuous. But its what-it-was-to-be, if being straight is other than the straight, is different. Let it be, for instance, duality. Then it judges either by another power or by the same differently disposed. In general, then, the way the things are separable from matter is how they relate to the intellect.

700. But when it becomes particular objects (429b5). Having reached certain conclusions about the potential intellect, which exists in potency to intelligible objects, the Philosopher now goes on to show how it is reduced to act.

And first, he shows how the intellect is sometimes in act;

and second, at now, as magnitude (429b10; [705]), what is the proper object of its actualization.

He explains how the intellect is actualized thus: the intellectual soul, we have said, is not the very species in act, but only in potency. (Lect. 1, nn. 677–83.) But when it becomes particular objects, that is, when the intellect is reduced to the act of the intelligible species, in the way that a knower does, that is, as having the habit of scientific knowledge, then it has the species actually, and then the intellect is spoken of as an intellect in act; this comes about as soon as such a one is able to act, that is, to do the intellectual activity called “understanding,” of himself. This is also just as someone actually has any form whatsoever when he can accomplish the activity of that form.

701. Yet though an intellect is in a certain way in act when it has intelligible species the way a knower does, nonetheless it is, then, in a way still in potency, but not in the same way as it was in potency before it acquired the science, either by being taught it or by its own discovery. For before it acquired the habit of a science—which is its first actuality—it could not become active at will; rather, it needed to be brought into act by something else. But once such a habit is acquired, the first act, the intellect has the power to bring itself into the second act, which is the activity, at will.

702. What is said here disproves the position of Avicenna, which is contrary to Aristotle’s position, regarding intelligible species.

For Avicenna maintained that intelligible species are not retained in the potential intellect, nor are they in it at all except when one is actually understanding. Rather, according to him, for it to actually understand anything, it must turn to a separated agent intelligence, from which the intelligible species flow into the potential intellect.

703. But against this, the Philosopher is clearly saying that the intellect brought to the act of the species in the way in which the science is the act is still an intellect in potency. For when the intellect is actually understanding, the intelligible species are in it by a perfect actuality; but so long as it has the habit of the science, the species are in the intellect in an intermediate mode between pure potency and pure actuality.

704. And because he asserted that once the intellect has become in a certain way actual with respect to the individuals of the things that it used to be in potency, then it is able to understand, whereas regarded in itself it is in no way in potency, someone could believe that when it comes to be in act it would not understand its very self. To avoid this, Aristotle adds that the intellect brought to act can understand not only other things, but it also is able to understand its very self.

705. Next, at now, as magnitude is one (429b10), Aristotle elucidates what the object of the intellect is. To understand him here, we must recall the problem stated in Metaphysics 7, namely, whether the what-it-is, that is, the “whatness” or essence of a thing—whatever is signified by its definition—is the same as the thing itself. (Aristotle, Metaphysics 7.6, 1031a15–1032a11; cf. Aquinas, Commentary on Metaphysics, bk. 7, lect. 5, nn. 1356–80.) And while Plato used to assert that the “whatnesses” of things (which he called “ideas” or “species”) were separated from the individual things, Aristotle was concerned to show that the whatnesses of things are not something other than the things except accidentally. For example, a white man and the whatness of a white man are not the same thing, because the whatness of man includes only what pertains to man’s species, whereas the thing called a “white man” includes something besides what pertains to the human species.

706. And the same is true of anything whose form exists in matter: there is something in it besides the principles of its species. For the species’ nature is individualized through matter; hence the individualizing principles and accidents of the individual are outside the essence of the species. That is why there can be many individuals under one species, and although they do not differ in the nature of the species, they nevertheless differ in virtue of their individuating principles. Hence, in all such things having form in matter, the thing and what it is are not altogether the same thing. For Socrates is not his humanity. But in things that do not have their form in matter, but are simple forms, there can be nothing outside the essence of the species; for the form itself is the entire essence. And in such things, therefore, there cannot be several individuals of the one species, nor in them can the thing and its what-it-is be different.

707. It also should be considered that natural things are not alone in having their species in matter; the same is also true of mathematical objects.

For there are two sorts of matter: sensible matter, from which the mathematical objects abstract and with which natural things blend; and intelligible matter, with which even mathematical objects blend. This should be understood as follows. It is manifest that quantity inheres in substance immediately, whereas sensible qualities, like white and black or heat and cold, are founded on quantity. Now, given two things of which one is prior to the other, if you remove the second, the first remains; hence removing sensible qualities in the intellect, there still remains in the intellect the continuous quantity.

708. Therefore there are some forms that require matter under the determinate disposition of sensible qualities, and such are all natural forms, and therefore, natural things are mingled with sensible matter. But there are other forms that do not need matter under the determinate disposition of sensible qualities, yet do require matter existing under quantity, such the triangle, the square, and the like; these are called “mathematicals,” and they abstract from sensible matter, but not from intelligible matter, insofar as continuous quantity remains within the intellect after being abstracted from sensible quality. Clearly, then, just as natural things have form in matter, so do mathematical objects, and on account of this in both there is a difference between the thing and what it is; this is why in both cases one finds many individual things under one species; for just as there are many men of one species, so too, there are many triangles under one species.

709. If these points are understood, the text of the Philosopher should present no difficulties. For he says that magnitude is one thing and the being of magnitude another, meaning a magnitude and what it is—for he calls the whatness of magnitude “the being of magnitude.” So also water is one thing and the being of water another, and so with many other things, that is, in all natural and mathematical objects. Hence his choice of these two examples is significant: for magnitude is a mathematical object and water is a natural one.

710. But this does not happen for all things; for in things that are altogether separated from matter, the thing and its what-it-is are the same. And because such substances are unknown to us, Aristotle could not assign proper names to them, as he could to natural and mathematical objects; so he describes them in terms drawn from natural things. That is why he says that in certain things, flesh is the same as the being of flesh. He does not mean that flesh is the same things as its what-it-is (else he would not have said this is the case in certain things, but would have simply said that flesh and flesh’s being are the same). Rather, he means that in certain things, that is, in those things separated from matter, that which is called a thing and what belongs to it—for instance, flesh and the flesh’s being—are the same.

711. And since for the diverse objects to be known diverse knowing powers are required, he concludes by saying that either the soul knows a thing with one power and its whatness with another, or it knows both with one and the same power in different ways. But it is obvious that flesh is not without matter, for the form of flesh is a determinate form in determinate sensible matter, like also the snub has a determinate sensible subject, namely, the nose.

Now, the soul knows this sensitive matter through the senses; that is why he adds that it is by the sense power that the soul judges the hot and the cold and so forth, of which flesh is a certain ratio, that is, proportion. For the form of flesh requires a certain determinate proportion of heat and cold and so forth.

712. But the being of flesh, that is, what flesh is, must be discerned by some other power. But this happens in two ways.

In one way, flesh itself and the whatness of flesh are known by powers wholly divided from each other; for example, the whatness is known by the intellectual power, and the flesh by the sensitive power; and this happens when the soul through itself knows the individual and through itself the nature of the species.

But in another way, the flesh and what flesh is, is known by something else, not by two distinct powers, but by one power knowing in two distinct ways—knowing in one way flesh; in another, the what-it-is of flesh. And this must happen when the soul compares the universal to the individual. For just as it would be impossible for us (as we have seen) to distinguish the sweet from the white if there were no common sensitive power that would know both, so too, we could not know the comparison of the universal to the individual unless there were one power that knew both. (Bk. 2, lect. 27, nn. 601–4.) The intellect, therefore, knows both, but in different ways.

713. For it knows the nature of the species, that is, what it is, directly by extending itself to that object; but it knows the individual thing by a certain reflection, inasmuch as it returns to the phantasms from which it abstracted the intelligible species.

This Aristotle expresses by saying that when it knows flesh by the sensitive power, but by something else, that is, by another power, it discerns the being of flesh, that is, what flesh is, either by a separate power—that is, when it knows flesh by the sense and the being of flesh by the intellect—or it knows flesh and the being of flesh by one and the same power standing in different ways, that is, as if it were bent back upon itself, the soul then knows the flesh, but when straightened, it discerns the being of flesh, that is, it directly apprehends the whatness of flesh, but through the bending back upon flesh itself.

714. Next, at again, in the things that exist by abstraction (429b18), he applies what he had said of natural objects to mathematical objects, saying that in the things that are through abstraction, that is, in mathematical objects, the account of which abstracts from sensible matter, the straight is as the snub; that is, mathematical objects have a matter just as natural things do (for the straight is a mathematical object and the snub a natural one). For the account of the straight includes the continuous just as the account of the snub includes a nose. But the continuous is an intelligible matter, just as a nose is sensible matter. Therefore, in mathematics also, the thing and what-it-was-to-be, for example, being straight and the straight, are different; hence too, even in mathematics, things and essences must be objects of different kinds of knowing.

715. As an instance of this let us suppose for a moment, with Plato, that the essence of a straight line is duality (for Plato identified the species and essences of mathematical objects with numbers, so that a point is unity, a straight line is duality, and so on). The soul, then, must know mathematical objects themselves and their essences by the same differently disposed. Hence, just as it can be shown, in the case of natural objects, that the intellect, which knows their essences, is other than the senses, which know the singular natural things themselves, so too, in the case of mathematics, it can be shown that the intellect, which knows their essences, is something other than the imaginative power, which apprehends mathematical objects themselves.

716. And lest it be said that mathematical objects are understood in the same way as are natural things, he adds that the way the things are separable from matter is how they relate to the intellect. This is why things that are separate from sensible matter in their being can be perceived only by the intellect, whereas things that are not separate from sensible matter in their being, but only in their account, are understood without sensible matter, but not without intelligible matter. Natural objects, however, although they are understood by abstraction from individual matter, are not understood by a total abstraction from sensible matter; for man is understood as composed of flesh and bones, though in abstraction from this flesh and these bones. This is why the singular individual is not directly known by the intellect, but by the senses or imagination.

717. From this text of Aristotle, it is apparent that the intellect’s proper object is indeed the whatness of a thing, which is not separate from things, as the Platonists thought. Hence this proper object of our intellect is not, as the Platonists held, something existing outside sensible things; rather, it is something existing within sensible things, even though the intellect apprehends the whatnesses of the things in a different way than they exist within the sensible things. For it does not apprehend them with the individuating conditions which belong to them in sensible things.

Nor need this involve the intellect in any falsehood, for there is no reason why, of two conjoined things, it could not understand one without understanding the other, as sight apprehends color without apprehending odor, though not without apprehending magnitude, which is the proper subject of color. In like manner, the intellect can understand a form apart from its individuating principles, though not apart from the matter on which the account of that form depends, just as it cannot understand the snub without thinking of a nose, but it can understand the curved without thinking of a nose. And it was just because the Platonists failed to draw this distinction that they thought that mathematical objects and the essences of things were as separated in being as they are separated in the intellect.

718. Furthermore, it is clear that the intelligible species, by which the potential intellect is actualized, are not in themselves the intellect’s object. For they are not related to the intellect as that which but rather as that by which it understands. For just as, in seeing, the species that is in one’s sight is not what is seen but is that by which one’s sight sees (for what is seen is the color that exists in a body), so also what the intellect understands is the whatness that exists in real things, but not the intelligible species (except insofar as the intellect reflects upon itself). For it is manifest that sciences are about whatever the intellect understands, but the sciences are about real things, not about the intelligible species or intentions (logical science alone excepted). Clearly then, the intellect’s object is not the intelligible species, but rather the whatness of the reality that is understood.

719. From which we can infer the futility of an argument used by some to prove that all men have only one potential intellect in common. They argue from the fact that all men can understand the same object; and they say that if there were numerically many human intellects, they would necessarily have many intelligible species. But the intelligible species is not the thing understood, but rather its likeness in the soul; hence, if there are many intellects in possession of a likeness of one and the same reality, the same reality will be understood by all of them. Besides, even the separated substances clearly understand the whatnesses of the natural things that we understand and their intellects are distinct. Hence, if the above argument were valid, its conclusion—that all men have only one intellect—would still involve a difficulty; for they cannot posit that there is one intellect for all the intelligences.