Five ways, five philosophical proofs for the existence of God. Yet one might wonder whether the Angelic Doctor has demonstrated the existence of a single ultimate being. Perhaps the unmoved mover of the first way is a different being than the perfect being of the fourth way … so on and so forth. Perhaps … but unlikely. St Thomas clearly intends each proof to identify an ontological deficiency, namely, the incapacity of beings to provide a metaphysical account of their existence. Only a being who is the transcendent fullness of being, who is self-existent Being, can provide an answer to the question, Why does the world exist instead of nothing? “On Aquinas’s view,” Edward Feser explains, “there can in principle be only one being whose essence and existence are identical, and thus which is Pure Being. Hence it is necessarily one and the same being on which all five proofs converge” (Aquinas, p. 121). The persuasiveness of the five ways, therefore, depends on our grasping the critical Thomist insight—the essence of God is his existence.
Orthodox Christians have always claimed for the triadic Deity the attribute of aseity. The divine self-sufficiency would seem to logically follow from the dogmatic claim that God freely and needlessly created the world from out of nothing. God possesses life, power, being within himself. He does not derive it from any other source. Thus St Athanasius:
For if it is an admitted truth about God that He stands in need of nothing, but is self-sufficient and self-contained, and that in Him all things have their being, and that He ministers to all rather than they to Him, how is it right to proclaim as gods the sun and moon and other parts of creation, which are of no such kind, but which even stand in need of one another’s help? (Contra Gentes 28)
Yet as standard and commonplace as the confession of God’s aseity may be within the tradition, many theologians find Thomas’s formulation of the doctrine incisive and fresh, even innovative. Even a theologian as critical of Hellenistic construals of divinity as Robert W. Jenson appreciates the Thomistic contribution:
According to Thomas Aquinas, the difference between Creator and creature is that in the case of creatures, existence and essence are distinct, whereas they are not in God. Essence is, of course, what something is; existence, in Thomas’ here innovative use, is the fact that something is. Simplifying greatly, we could know absolutely everything about what a putative creature would be, without knowing whether the thing so described actually exists. Not so with God: could we—as short of the Kingdom we cannot—know what God is, we would merely therein discover that he is. God contains within what he is the reason that he is; we do not.
In my view, Thomas’ brilliant move must surely suffice for all ordinary theological purposes, and I invoke it regularly. Yet I am haunted by the feeling that it also is too abstract to quite fit the biblical narrative. For Thomas himself, the non-distinction of existence and essence in God belongs to his doctrine that God is Being. I agree, but I note that the Eastern doctrine that God is above Being seems to exegete Scripture with equal plausibility, which suggests a certain loose fit in both cases. (“Creator and Creature,” Theology as Revisionary Metaphysics, pp. 158-159)
What Jenson sees as a weakness of the Thomistic claim of the identity of the divine essence and existence—namely, its abstraction from the biblical story—I see as its strength. The proper distinction between Creator and creature cannot be adequately stated in the terms of the biblical narrative, though it first emerges and is apprehended within this narrative. At this point the Scriptures point us to a mystery they cannot say.
On the surface the Thomist assertion that the essence (essentia) of God is identical to his existence (esse) merely restates in scholastic idiom what the Church has always taught about the divine aseity and the contingency of the world: God is uncreated; everything else ain’t. But some Thomists believe that the formulation illuminates the nature of being in a way that was unavailable to earlier Christian philosophers. This illumination is expressed in Thomas’s use of two words—esse (being, existence; infinitive form of the verb to “to be”) and ens (entity, a being; plural: entia). Etienne Gilson recommends that English translators use “being” to render ens and “act of being” to render esse.
Thomas begins his metaphysical reflection, not with ideas and concepts, but with the beings that we apprehend with our senses. We see a rock, we hear a tree falling, we smell a flower, we taste the Cabernet Sauvignon, we feel the caress of our lover. By an act of intellect we apprehend the nature or essence of these things, i.e., we grasp them as substantial forms, but by an act of judgment we penetrate to their metaphysical act of existing and are thus able to affirm of each “it is.” Our judgment, Gilson says, “reaches the very act-of-being. When we speak of the being of any being (ens), we are speaking of something having an act-of-being (habens esse)” (The Christian Philosophy of St. Thomas Aquinas, p. 40). To be is not a static state of existence or even presupposition for thought and action. It is event, a dynamic presence and self-revelation. A being exists, explains Gilson, “only in virtue of the existential act which makes it a real thing” (p. 34):
Thus understood, the act of existing lies at the very heart, or if one prefers, at the very root of the real. It is therefore the principle of the principles of reality. First absolutely, it even precedes the Good, for a being is only good in so far as it is a being, and it is a being only in virtue of the ipsum esse which permits us to say of it: this is “being.”
To understand this doctrine in its proper nature, it is necessary to remember that esse, like every verb, designates an act and not a state. The state in which the esse places that which receives it is the state of ens, that is to say, of that which is a “being.” Because essences are the proper object of human understanding, we tend ceaselessly to step down from the plane of the act-of-being to that of things (res). This is a natural inclination, but the metaphysician must make every effort to remount, that is to emphasize that being has meaning only in relation to actual existence. Beyond what is most perfect and most profound in the real, there is nothing. Now, what is most perfect is the act-of-being (ipsum esse) “since it is related to all things as their act. In fact, nothing has any actuality save in that it exists. The act-of-being (ipsum esse) is the actuality of everything else, even including forms. Its relation to other things therefore is not that of receiver to received but of received to receiver. Indeed, when I say of a man, or of a horse, or of anything else: that exists, the act of being (ipsum esse) is taken as formal and received, and not as that to which the act-of-being belongs.” St. Thomas is here noticeably making, as it were, a supreme effort, so much so that the meaning fairly rings through the formulae, to express the unique character of ipsum esse and its transcendence. But precisely because it is the summit of the real, it is also its heart. “The act-of-existing is more intimate to anything whatsoever than is what determines it.” (p. 34)
One might think, as philosophers both before and after Aquinas did, that existence should be described as a property that something possesses (my Collie has the properties of sable-and-white fur, a long nose, and a sweet disposition … and by the way, she also exists), but Thomas denies this. In his view to say that something exists does not describe any given ens; it does not tell us about its nature or qualities. Alvin Kimel is a man and Tiriel is his favorite dog, but they are distinguished from each other not by their respective acts of existing but by all sorts of other features. As Brian Davies writes, “For Aquinas there is nothing which can be characterized simply by saying that it is” (Aquinas, p. 29; see “Aquinas, God, and Being“). Esse is more fundamental than ens or even essence. To make matters a tad clearer, consider fictional or mythological beings. If you have read Lord of the Rings or watched The Two Towers, you know what Ents are. If you don’t, zip on over to The Encyclopedia of Arda and check out the entry: “A race of giant, tree-like people whose purpose was to protect the forests of Middle-earth.” If it had also stated, “But they don’t exist in the real world,” nothing about Ents qua Ents would have changed. Whether they exist or do not exist, their Entish nature remains the same.
And so it is with all beings. Their existence is not identical to their essence. Men and dogs have esse and participate in esse, but they are not esse. They do not contain existence within themselves but must receive it from their transcendent source. Only with the uncreated Deity may we say that he is his existence. As the Lord told Moses on Mount Sinai, “I AM.”
“God is not only His own essence,” declares Thomas, “but also His own esse” (ST I.3.4)—or perhaps we should render, “his own act of existing.” God is the Act that underlies and grounds the cosmos. He is not a thing (ens), not even the supreme Thing. He is the doer and doing of existence, perfectly realized activity and energy, unbounded actuality unconstricted by limiting essence, the infinite plenitude of Being. “God exists as the doing of all being,” elaborates Timothy McDermott, “the existence that acts in all existence, an existence in the world’s existing but not of it, no thing, but not therefore nothing” (Preface to Summa Theologiae, p. xxxii). Not a noun, we might say, but a verb. Thus Gilson:
Why, Saint Thomas asks, do we say that Qui est is the most proper name among all those that can be given to God? And his answer is because it signifies “to be”: ipsum esse. But what is it to be? In answering this most difficult of all metaphysical questions, we must carefully distinguish between the meaning of two words which are both different and yet intimately related: ens, or “being,” and esse, or “to be.” To the question: What is being? the correct answer is: Being is that which is, or exists. If, for instance, we ask this same question with regard to God, the correct answer would be: The being of God is an infinite and boundless ocean of substance. But esse, or “to be,” is something else and much harder to grasp because it lies more deeply hidden in the metaphysical structure of reality. The word “being,” as a noun, designates some substance; the word “to be”—or esse—is a verb, because it designates an act. To understand this is also to reach, beyond the level of essence, the deeper level of existence. …
A world where “to be” is the act par excellence, the act of all acts, is also a world wherein, for each and everything, existence is the original energy whence flows all that which deserves the name of being. Such an existential world can be accounted for by no other cause than a supremely existential God. (God and Philosophy, pp. 63-65)
At this point I suspect some readers may have lost all sympathy with Aquinas. Perhaps you have even begun chanting the famous memorial of Pascal: “God of Abraham, God of Isaac, God of Jacob—not of the philosophers and scholars!” I know this response well and intimately, but before giving up on him, remember that St Thomas was a man of deep prayer, thoroughly formed by the Bible, Mass, and the Offices of the Church (see Denys Turner, Thomas Aquinas—I cannot recommend this book too highly). He did not see a conflict between faith and reason. Perhaps neither should we.
Protestant and Orthodox theologians commonly claim that Aquinas, along with his fellow scholastics, presents us with a static understanding of divinity, an immutable, impassible, impersonal substance, the unmoved mover of Aristotle, certainly not the living God of Israel and the apostolic Church. This was a common theme of my catechetical teaching when I was a parish priest. I am feeling pretty silly now. As apprehended by Thomas, esse is the very opposite of the static and inert. But more, of course, needs to be said. In particular we want to see how the God whose essence is his existence is also personal, indeed Person. As Eleonore Stump has recently argued, Thomas had no problem speaking of God as one who hears prayers and acts within the world he has made. Read his biblical commentaries, she urges, and you will find that “Aquinas’s God is highly responsive to human beings and engaged with them in personal and interactive ways. He is a God who is a particular and personal friend to every person of faith. And he looks very like the biblical God” (The God of the Bible and the God of the Philosophers, p. 108). I suspect that Gilson would object to Stump’s downplaying the metaphysical side of Thomas (she pointedly criticizes scholars like Brian Davies and David Burrell who assert that God is not a being); but he certainly would agree with her that no conflict exists or can exist between the Esse whom Thomas thought about and the Father to whom he prayed.
The infinitely creative God of the Bible meets the self-existent God of the philosophers, and surprise of surprises, they are the very same God—Ipsum Esse Subsistens.