Again, before a contingent thing comes into actual existence it may be virtually and potentially in the active powers and passive potentialities of other actually existing contingent things: as the oak, for instance, is in the passive potentiality of the acorn and in the active powers of the natural agencies whereby it is evolved from the acorn; or the statue in the block of marble and in the mind and artistic power of the sculptor. But neither is there any question here of the relation of such potential being or essence as a thing has in its causes to the actual existence of this thing when actually produced. Whatever being or essence it has in its active and passive causes is certainly really distinct from the existence which the thing has when it has been actually produced. Nor is there any doubt or dispute about this point. At the same time much controversy is due to misunderstandings arising from a confusion of thought which fails to distinguish between the essence as purely possible, the essence as virtually or potentially in its causes, and the essence as actually existing. It is about the distinction between the latter and its existence that the whole question is raised. And it must be borne in mind that this essence, whether it is really distinct from its existence or not, is itself a positive reality from the moment it is created or produced. The question is whether the creative or productive act—whereby this essence is placed “outside its causes,” and is now no longer merely possible, or merely virtual or potential in its causes, but something real _in itself_—has for its term _one reality_, or _two realities_, _viz._ the essence as real subjective potentiality of existence, and the existential act or perfection whereby it is constituted actually existent.(117) The question is exclusively concerned with the essence which began to exist when the contingent being came into actual existence, and which ceases to exist when, or if, this being again passes out of actual existence; and the question is whether this essence which actually exists is really distinct from the existence whereby it actually exists. Finally, the question concerns the essence and existence of any and every actual contingent reality, whether such reality be a substance or an accident. Of course it is primarily concerned with the essence and existence of substances; but it also applies to the essence and existence of accidents in so far as these latter will be found to be really distinct from the substances in which they inhere, and to have reality proper to themselves.