12. Purely substantive being, is nowhere met with, except in the following proposition: being is, or what is is; in all other propositions there is involved, even in the subject itself, some predicate which determines the mode. When we say, the desk is, notwithstanding that the direct predicate of the proposition is the word _is_, there yet enters into the subject _desk_ a determination of the being of which we speak, and that is of a being which is a desk. We were, then, right in saying that the verb _to be_, in its purely substantive meaning, is met with in no other proposition than this: being is. This is perfectly identical, absolutely necessary and convertible, that is, the predicate may be observed of all subjects, and the subject of all predicates. Suppose we give the proposition a different form; being is existing; we can still say all being is existing, or the existing is being; that is, all that exists is being. 13. If it be objected that possible being does not exist, we answer that purely possible being is not, strictly speaking, being; but that it does exist, in the same mode in which it is, that is, in the possible order. As we shall, however, treat this question more fully hereafter, we now turn to the propositions in which being is copulative. The desk is, is equivalent to this, the desk is existing. It is true that every real desk is existing, but real is the same as existing; and thus it might, in one sense, be said that the proposition resembles this other: all being is. But here we detect a difference; it consists in this, that the idea of existence does not necessarily enter into that of desk, for we can conceive of a desk which does not exist, but we cannot conceive of a being as such without a being, that is, of a being which is not being. A very notable difference is every way perceptible between the two propositions; in the former, the subject may be affirmed of all predicates by saying, all that is existing is being; but it is evident that we cannot say all that is existing is desk. 14. The reason of this is that the proposition, being is, is absolutely identical; it is the expression of a pure conception reduced to the form of a proposition; and, consequently, the terms which serve as extremes may be taken indiscriminately the one for the other; being is, whatever is, is being; being is existing; every thing existing is being. But different orders of ideas are combined in all other propositions; and, although the common idea of being is applicable to all, as this idea is essentially indeterminate, it does not thence follow that one of the things to which the general idea corresponds is identical with the other, alike entering into the same general idea. Being belongs to every existing desk; but not, therefore, is every thing a desk.