BEING IS THAT WHICH IS PREDICATED OF NOTHING ELSE.
It would seem that (physical) "being" is that which is not predicated of anything else;[355] for whiteness and blackness may, for instance, be predicated of some white or black subject. Likewise with the idea of "doubleness";—I mean here not the doubleness which is the opposite of one half, but the doubleness predicated of some subject, as when one says "this wood is double." So also paternity, and science, are attributes of another subject, of which that is said. So space is that which limits, and time that which measures something else. But fire, or wood considered as such, are not attributes. Neither are Socrates, nor composite being (composed of matter and form), nor form which is in the "being," because it is not a modification of any other subject. Indeed, form is not an attribute of matter; it is an element of the combination. "Man" and "form of man" are one and the same thing.[356] Matter also is an element of the combination; under this respect, it may be predicated of a subject, but this subject is identical with itself. On the contrary, whiteness, considered in itself, exists only in the subject of which it may be predicated. Consequently, the thing which exists only in the subject of which it is predicated is not (physical) "being."[356] "Being," on the contrary, is that which is what it is by itself. In case it form part of some subject, then it completes the combination; whose elements exist each in itself, and which are predicated of the combination only in a condition other than that of existing in it. Considered as a part, "being" is relative to something other than itself; but considered in itself, in its nature, in what it is, it is not predicable of anything.[357]