History of Western Philosophy - Bertrand Russell [99]
We now come to a new statement, which at first sight seems difficult. The soul, we are told, is the form of the body. Here it is clear that 'form' does not mean 'shape'. I shall return later to the sense in which the soul is the form of the body; for the present, I will only observe that, in Aristotle's system, the soul is what makes the body one thing, having unity of purpose, and the characteristics that we associate with the word 'organism'. The purpose of an eye is to see, but it cannot see when parted from its body. In fact, it is the soul that sees.
It would seem, then, that 'form' is what gives unity to a portion of matter, and that this unity is usually, if not always, teleological. But 'form' turns out to be much more than this, and the more is very difficult.
The form of a thing, we are told, is its essence and primary substance. Forms are substantial, although universals are not. When a man makes a brazen sphere, both the matter and the form already existed, and all that he does is to bring them together; the man does not make the form, any more than he makes the brass. Not everything has matter; there are eternal things, and these have no matter, except those of them that are movable in space. Things increase in actuality by acquiring form; matter without form is only a potentiality.
The view that forms are substances, which exist independently of the matter in which they are exemplified, seems to expose Aristotle to his own arguments against Platonic ideas. A form is intended by him to be something quite different from a universal, but it has many of the same characteristics. Form is, we are told, more real than matter; this is reminiscent of the sole reality of the ideas. The change that Aristotle makes in Plato's metaphysic is, it would seem, less than he represents it as being. This view is taken by Zeller, who, on the question of matter and form says:4
'The final explanation of Aristotle's want of clearness on this subject is, however, to be found in the fact that he had only half emancipated himself, as we shall see, from Plato's tendency to hypostatize ideas. The "Forms" had for him, as the "Ideas" had for Plato, a metaphysical existence of their own, as conditioning all individual things. And keenly as he followed the growth of ideas out of experience, it is none the less true that these ideas, especially at the point where they are farthest removed from experience and immediate perception, are metamorphosed in the end from a logical product of human thought into an immediate presentment of a supersensible world, and the object, in that sense, of an intellectual intuition.'
I do not see how Aristotle could have found a reply to this criticism.
The only answer that I can imagine would be one that maintained that no two things could have the same form. If a man makes two brass spheres (we should have to say), each has its own special sphericity, which is substantial and particular, an instance of the universal 'sphericity', but not identical with it. I do not think the language of the passages I quoted would readily support this interpretation. And it would be open to the objection that the particular sphericity would, on Aristotle's view, be unknowable, whereas it is of the essence of his metaphysics that, as there comes to be more of form and less of matter, things become gradually more knowable. This is not consistent with the rest of his views unless the form can be embodied in many particular things. If he were to say that there are as many forms that are instances of sphericity as there are spherical things, he would have to make very radical alterations in his philosophy. For instance, his view