Aristotle, being (to on), simply speaking, is an equivocal pros hen whose primary instance is form (morphe, eidos, or idea).62 What it means for something to be itself can be expressed as accidental being, as truth, as the categories, and as being-potential and being-at-work (energeia).63 It is the same being that can be expressed in this fourfold manner. As is known, the sense that accounts for the others is ousia (Entity).64 Ousia, according to Aristotle, is either matter, form, or the composite of matter and form. Form is the most proper instance of Entity, and its most fundamental meaning is reducible to act (energeia, entelecheia), a principle that can be pointed at but not defined in terms of anything more comprehensive.65
To grasp the ontological depth of gift, it suffices for our purposes to indicate how the circularity of form and act clarifies the issue of the concrete singular’s existence. For Aristotle, form accounts for both the cause of a singular being (it is thus: to ti en einai—what-was-being) and for its intelligibility (logos).66 Form is that principle, internal to a thing, thanks to which a concrete singular is a whole and not merely a heap of characteristics. For Aristotle, unlike Plato, form is in a sense identical with the particular being and different from it, but only in thought.67 Form is separate in notion (not abstracted) and exists as separate from matter only in human thinking. This is why, although form is the principle of the definition, it is not a universal. For Aristotle, form is thus the principle that accounts both for this singular being and for its universal meaning. It is a this (tode ti) without being singular. Form is a this that causes a particular being to be itself. To know the form therefore is to know both, for example, “this horse” and “horse.” For Aristotle, as Owens clarifies, form is “prior to and act of both composite Entity and logical universal.”68
Form is an active principle and not an archetype that is received by finite beings. It is act, that is, being-at-work-staying-itself (entelecheia).69 The form of a horse does not simply account for its horse-ness; it is also what is responsible for its neighing, galloping, grazing, breeding, etc. This “being at work” (energeia) therefore has no end outside of itself. The purpose of act, in other words, is the enjoyment of being. Like seeing and contemplating, entelecheia rests in itself. This is primordially the case for the unmoved mover, which is self-thinking thought.70 Of course, the actuality (energeia) of concrete singular beings is always imperfect. A single instance (a horse) never embodies its entire pattern (horse-ness). This is why every sub-lunar being, for Aristotle, is constituted by these two principles: actuality and potency—which is the possibility for actuality to be present. The “material” can become a single being if it receives the form from an already actual being. Once it receives the form, potency, while limiting the act of one being, is also the ability, the capacity, to live up to the form. Inasmuch as a singular being continues being what it is, both act and potency, form and matter, remain present in the actual existing being. Potency thus indicates both the limiting of a form and the capacity to live up to it, without being able to identify itself fully with the form.71
The unmoved mover is ultimately what is responsible in Aristotle’s understanding of form, whose primary instance is act. Self-thinking thought is the guarantor that there has always been and will always be form and order in the cosmos. Thus, to adopt this concept of form entails conceding the eternity of the world. Every being is necessary: the unmoved mover and the singular beings that imitate the unmoved mover precisely by having form and by being ordered.72 This view of form and its relation with act prevents Aristotle from having to give an account of the existence of single beings. Aristotle’s reflection is not open to the consideration of the first level of givenness of the concrete singular, that is, its existence as gift. In Aristotle’s metaphysical view of the cosmos, there is no real distinction between esse and essence. Let us see why.
As his treatment of accidental beings shows, existence is not reducible to form and so it does not yield scientific knowledge, which is the goal of the collection of books grouped under the name Metaphysics.73 Existence has no place in contemplation, and therefore there is no need to account for it. It is true that some passages of the Metaphysics indicate the difference between what something is and its existence.74 Nevertheless, when looked at in the presupposed, broader context of the Posterior Analytics, the inquiry regarding the facticity of a being (“if-it-is”) does not demonstrate the “existence” of a particular essence.75 “To ask whether there is an eclipse or not,” Aristotle writes, “is . . . the same as asking whether there is an account (logos) for it, i.e., the moon is eclipsed; and if this condition actually exists, we assert that it also actually exists.”76 As Owens indicates, Aristotle deals with the universal and necessary connections between the elements that form part of the definition and not with the existence of a thing. If the connection is accidental, then we are to conclude that there is no fact (e.g., a centaur). In the case of an evident indemonstrable, one can ask what it is. If it is a fact but it is not evident or indemonstrable (as the case of the lunar eclipse observed from the earth rather than the moon), one can inquire further what it is. For this reason, Owens concludes that for Aristotle “the ‘if-it-is,’ is a quasi-generic knowledge of the thing sufficient to establish it as a Being. The ‘what-it-is’ is the specific knowledge obtained through the addition of the proper difference.”77 Thus, there is no need to account for existence, nor is this “lack” a deficiency. Perfection is contained within the limits of the singular, not the infinite. Aristotle does not seem to wonder before the miracle of being given; he rather admires the intrinsic, ever-lively necessity of the order of the world.
Aquinas, benefitting from the doctrine of creation ex nihilo, revisits the Aristotelian principles and argues that the fundamental difference traversing every singular being is not so much between form and matter, or act and potency, but between what they are and their esse.78 The difference between esse and the Entity of any singular being can help us to explore the first level of givenness: the meaning of the existing of beings as gift. Numerous authors have clarified that Aquinas does propose a real distinction between esse and essence in singular beings.79 Benefitting from their work, it suffices to recall two arguments that illustrate the gift-ness of the “to be” of every singular being. The first clarifies that everything that “is in the genus of the substance is composite with real composition.”80 Whatever is a substance has an existence of its own. Yet there are many different members that belong to the same genus. The difference, then, indicates that in each existing being, its being (esse) and the thing itself must differ. Whereas in Aristotle form is responsible for both the essence and the singularity of a being, in Aquinas the “to be” of a thing no longer depends on the form—when the being is considered as a single, self-standing creature. Leaving aside other arguments that do not necessarily presuppose the proof of the existence of God, ipsum esse subsistens, if we turn to those that do, it becomes clear why there is, according to Aquinas, a real distinction between esse and essence in concrete singular beings.81 Aquinas contends in one of the latter arguments that every being causes an effect that is proper to its essence and that the effect images the essence: fire, for example, communicates light and heat; the architect communicates the form of the house he has in himself to the heap of material that can receive this form. At the same time, they also communicate an effect that is not directly proper to their own essences since they all give this other effect: heat makes something to be hot, and the builder gives being to a house. The communication of esse can be explained only thanks to that being the immediate effect of whose essence is esse itself: God. It is only God who is the simple, self-subsisting being whose essence is his esse, whereas all the others are given to participate in esse and, thanks to this participation, can also communicate esse.82
The difference between esse and what a being is affects every created being, regardless of its being composed of matter and form or its being a spiritual being. Even in the latter, according to Aquinas, it is still possible to find the distinction between being (esse) and what is (quod est).83 Finite beings, from the lowest to the highest, participate in esse. With this distinction, Aquinas separates the two main characteristics of form proposed by Aristotle. For Aquinas, form accounts for the intelligibility of a singular being and esse for its actuality. Form is no longer the highest principle of actuality. Form has to receive esse (act) in order to be the principle of being for the substance. “Nothing has actuality (actualitatem) if not inasmuch as it is: hence existence
