Which Essence Is Brought into Being by the Existential Act?

ALTHOUGH SCHOLARS agree that according to Thomas Aquinas there is a distinction between essence and existence (esse) in created things, they are often unclear about the nature and even the terms of this distinction. In this article, for the sake of clarity, I follow Joseph Owens in translating “esse” as “existence” when it means the existential act of a being. One should perhaps first ask what Thomas means by “essence” in this context. I argue that the essence that is actualized by existence is the essence that is a determinate nature in an individual and not the essence absolutely considered. This essence in individuals has a potential being that is actualized by existence.

Owens and some other Thomists argue that the essence at stake in this distinction is the essence absolutely considered. Owens writes:

[An] essence is individual when existent in the human intellect, but common and not existent when considered absolutely. Essence as common nature, essence in its absolute consideration, and essence contrasted with existence coincide. All three denote the essence that may be brought into being by existential act, either in reality or in cognition.¹

Owens emphasizes that this essence has no being of its own. I will argue that the essence absolutely considered is an essence to which it makes no sense to attribute existence. The essence that is really distinct from existence is distinct from existence in the way that being in potency is distinct from being in act.

First, I will show that Owens neglects an important distinction between two kinds of potency, namely, that which results from God’s power to create and that which belongs to an existing essence that receives an existential act. Second, I will consider the text of Thomas’s early De ente et essentia, in which Thomas makes the distinction between the kinds of essence or nature, of which one is the essence absolutely considered. I will show that when Thomas establishes the distinction between essence and existence as one of potency and act, he has in mind not essence absolutely considered but the essence that is in individuals. Third, I will show that this interpretation of De ente is the only one that is compatible with Thomas’s statements about the distinction between nature and existence in his Christological treatments. Although there are many relevant texts, the Christological discussions perhaps most clearly bring out the relationship between essence or nature, the individual substance (suppositum or hypostasis), and existence.

I. Two Kinds of Potency

A distinction between two kinds of potency is important for understanding how essence is really distinguished from existence. First, an essence can be considered as merely possibly existing. In this sense an essence depends only on the being of the divine essence. Essence itself has no being before it is created except insofar as it is in God’s essence.² It is in potency with respect to the ability to come into existence at all by an agent.³ Second, an essence can be considered insofar as it is actualized by existence. In this second sense essence receives being. It is in potency to the existence that it receives in a way similar to that in which matter is in potency to the form that it receives. This second kind of potency is the kind that is at stake both in the distinction between essence and existence and in the distinction between matter and form.

Thomas thinks that the distinction between essence and existence is needed to provide a real composition in created creatures that lack matter, namely, the angels or spiritual creatures. All created being is divided between potency and act. Material creatures are in potency because of their matter. Since angels lack matter, there must be another explanation for their potency. Thomas writes:

There is to consider in created things a twofold act and a twofold potency. For first a certain matter is as potency in respect to form, and form is its act; and again a nature constituted from matter and form is as potency in respect...