It is said:
On this view the assertion that the world is eternal is even less tenable, for its coming-to-be is perfectly possible under this assumption.

Moreover, here the Essence acts only through an intermediary, not by Its own power, and every act is necessarily originated; it is therefore impossible for the product of that act to be eternal. An effect is not subject to more than one act, and were the effect eternal it would have existed before the act that produced it—an absurdity.

If it is objected: “According to this position the Essence will of necessity be accompanied by successive things subsisting within it; so let the same be said of the successive events in the celestial spheres,”

We reply:
The difference lies in the fact that the Essence is necessary in and of Itself; none of Its attributes or states depends on anything external. Hence, if it is said that It produces the second on condition that the first has ceased, no impossibility follows. This contrasts with the contingent effect, which possesses nothing of its own; it depends, in its very being, its attributes, and its states, upon Another—and that Other is the Creator of them all. Accordingly, if the Creator is conceived as a single, simple entity in whom no attribute or act inheres, it is impossible for His Essence to be the cause of mutable, manifold realities; this is even more impossible than saying that He acts after previously not acting. For if the cause contains no change or multiplicity, the appearance of change or multiplicity in its effect is impossible; just as, if the cause itself were subject to change and multiplicity, the effect could never be one and simple, owing to the correspondence that must exist between cause and effect.

For this reason they say, “Only one proceeds from the One,” and the statement is true in itself. Yet their prior assumption of a simple first principle from which no act proceeds is false, and likewise