Latin: actus essendi
Italian: atto di essere
English: act of being
Spanish: acto de ser
French: acte d'être
German: Akt des Seins (Seinsakt)
Latin: actus essendi
Having accepted wholeheartedly the Catholic faith, Jacques Maritain understood philosophical investigation to be “a wisdom of reason not closed but open to the wisdom of grace” (Le Philosophe dans la Cite, Paris, 1960, p. 27.)
This spirit of openness and capacity to receive the light of grace led him to the universality of the philosophy of being, the philosophy of the ‘actus essendi,’ whose transcendental value paves the most direct way to rise to the knowledge of ‘Being’ and pure Act, namely to God.
More than any other facet, Jacques Maritain drew attention to this central intuition of the philosophy of Saint Thomas which thus can be called “the philosophy of the proclamation of being,” “a chant in praise of what is” (The Angelicum Address, 1979, no. 6.)
It is enough that we should think of the extraordinary philosophic genius of Saint Thomas.
To say, as so many professors are fond of doing, that the philosophy of Saint Thomas is the philosophy of Aristotle is a gross error, as Gilson has rightly insisted.
The philosophy of Saint Thomas is that of Saint Thomas.
And it would be as big a mistake to deny that Saint Thomas owes his philosophy to Aristotle as that Dante owes his language to the fine raconteurs of his country.
Such an extraordinary conjunction of swift insight (one must be something of a poet for that) with ironclad logical rigor may be found in Aristotle too; because he was, in the world of philosophers, both the greatest realist and most perspicacious discoverer of the first apperceptions of the intellect, and the strictest instructor in the unforgiving exigencies of a rigorously rational work, the founder of metaphysics furnished the principles.
He missed, however, those conclusions whose object is the loftiest and which matter most to us.
But Saint Thomas did not just sift out or rectify conclusions – which would, after all, have been a minor contribution. He was possessed of an incomparably deeper vision of the principles themselves; his metaphysical intuition impelled the one he was always to call “the Philosopher” infinitely beyond Aristotelianism and the whole of Greek thought.
The metaphysics of Saint Thomas is not the metaphysics of Aristotle, because it is the metaphysics of Aristotle entirely transfigured.
In other words, Saint Thomas the theologian has, in the service of theology, humbly and without putting in a claim, brought metaphysical wisdom to the most basic and universal degree of intuitive grasp possible to reason.
A metaphysics of “Sein” (esse), a metaphysics born from the intuition of the act of existing [actus essendi] – and whose primary object is this primordial and all-embracing intelligible reality – has the capacity to welcome, recognize, honor, set to rights all that is.
“To conceive God,” writes Gilson, “as the Act of being pure and subsisting by itself, cause and end of all other beings, is by the same token to give oneself a theology that can do justice to whatever is true in other theologies, just as the metaphysics of esse has what is needed to do justice to whatever is true in other philosophies” (Gilson, Trois Lecons sur le Thomisme, p. 700.)
As for the metaphysics which supports such a theology, and without which the latter would not have been (it is this metaphysics which, from the side of reason, provided the indispensable spark), let us cite further lines of our friend:
“For those who live on it, the metaphysics of the Common Doctor accepted in its fullness is a ne plus ultra for the understanding. At once unsurpassable in its own right and inexhaustible in its consequences, this metaphysics is the human understanding itself in its permanent work of rational interpretation of man and the universe” (Gilson, Trois Lecons sur le Thomisme, p. 707.)
Well, we are thus led to consider briefly the relation of Saint Thomas with time. Please pardon me for being myself out-of-date: there is an up-to-dateness which, while bound to manifest itself in time, is, of itself, above time, that’s the up-to-dateness of truth.
The doctrine of Saint Thomas, being essentially grounded in truth, and therefore, as I have already pointed out, open to the whole future, has, of itself, a supra-temporal up-to-dateness.
In other words, the doctrine of Saint Thomas was bound to manifest in time – after Saint Thomas – its supra-temporal truth.