4. If, on occupying ourselves with this sense-world, we wished to determine the nature of bodies, would we not begin by studying some part thereof, such as a stone? We could then distinguish therein substance, quantity--such as dimension--and quality, such as color; and after having discovered these same elements in other bodies, we could say that the elements of the corporeal nature are being, quantity, and quality; but that these three coexist; and that, though thought distinguish them, all three form but one and the same body. If, besides, we were to recognize that movement is proper to this same organization, would we not add it to the three elements already distinguished? These four elements, however, would form but a single one, and the body, though one, would, in its nature, be the reunion of all four. We shall have to take the same course with our present subject, intelligible Being, and its genera and principles. Only, in this comparison, we shall have to make abstraction of all that is peculiar to bodies, such as generation, sense-perception, and extension. After having established this separation, and having thus distinguished essentially different things, we shall arrive at the conception of a certain intelligible existence, which possesses real essence, and unity in a still higher degree. From this standpoint, one might be surprised how the (substance which is thus) one can be both one and many. In respect to bodies, it is generally recognized that the same thing is both one and many; the body can indeed be divided infinitely; color and appearance, for instance, are therein very differing properties, since they are separated here below. But in respect to the soul, if she be conceived as one, without extent, dimension and absolutely simple, as it appears at first sight, how could we, after that, believe that the soul were manifold? We should have here expected to reach unity, all the more as, after having divided the animal in body and soul, and after having demonstrated that the body is multiform, composite and diverse, one might well, on the contrary, have expected to find the soul simple; and to have accepted this conclusion as final, as the end of our researches. We would thus have taken the soul as a sample of the intelligible world, just as the body represents the sense-world. Having thus considered this soul, let us examine how this unity can be manifold; how, in its turn, the manifold can be unity; not indeed a composite formed of separable parts, but a single nature simultaneously one and manifold. For, as we have already said, it is only by starting from this point and demonstrating it, that we will establish solidly the truth about the genera of essence. THE SOUL IS A PLURAL UNITY OF SEMINAL REASONS.