The contention that, once its necessitating cause is set aside, a thing’s very essence can equally admit existence or non-existence is invalid for several reasons.

First, the claim rests on the assumption that the entity possesses an actual essence in external reality distinct from the concrete existent, and that this essence remains fixed even when the existent itself is absent. This is false. Outside the mind there is no reality for the thing except the very existent that is established there, and whatever constitutes the reality of existence can in no way accept non-existence. There is no external quiddity that persists in a state of non-being so that existence might subsequently attach to it; rather, the essence we know and conceive in the mind is sometimes found in external reality and at other times not.

We have discussed this at length elsewhere, for it touches on the view held by certain Muʿtazilites and others who say that the nonexistent is nevertheless “something,” and on the position of the philosophers and their followers who maintain that quiddities are fixed in the external realm and are identical with particular existents. Both positions are erroneous. The intelligible distinction is simply between what is known in the mind and what is found in concrete reality. Thus, when one says of a mental concept that it is “something in the mind,” “established in knowledge,” or calls it a “quiddity,” and when one says that the quiddity of a triangle is established in the intellect while its external existence remains in doubt, this is correct. But to assert that, outside the mind, there exists a fixed essence that is nonetheless not existent, or that the quiddity of a triangle—or anything else—subsists externally while failing to exist, is patently false, as clear reflection and numerous proofs show, and as has been explained elsewhere.

Second, even if one were to concede that a contingent being has an essence other than its existence, once that existence accompanies it eternally and unceasingly—being necessary through Another—then that essence could never be supposed to be nonexistent. Saying, “in itself it has no existence,” when one has posited some essence apart from existence, in no way entails that it may equally be nonexistent or existent while one is simultaneously affirming that its existence is necessary from pre-eternity to eternity.

Third, the Agent must precede His particular effect; He cannot be simultaneous with it in time. The examples they cite—such as the precedence of the hand’s movement over the movement of the ring—and their claim that this illustrates causal precedence, involve no efficient cause at all; they are merely conditions in the matter, and no one can