Thesis XX. -- It is not evident that no creature whatsoever can exist from eternity.
100. The great doctors of the middle ages agreed that eternal creation was not a necessity; they differed from one another on the less important point whether eternal creation is or is not intrinsically impossible.
St. Thomas Aquinas considered the controversy hopeless, at least in its most general form not descending to the particular inquiry whether this or that given creature -- man, for instance -- could possibly have existed from eternity.{29} We say only that the impossibility of a creature which had no beginning cannot be demonstrated. In order to prove this statement, it will be enough to show that the arguments against the possibility of eternal creation are by no means decisive. The most forcible are the following four, to each of which we will reply --
101. First Argument. Every efficient cause must exist before its effect. But if eternal creation is admitted, God, the efficient cause of the being created from eternity, does not exist before His effect. It is, therefore, against reason to admit eternal creation.
Answer. It is not to be denied that an efficient cause which produces its effect gradually must exist before its effect exists; whence it follows that the existence of all effects produced by corporeal substances is posterior to that of their causes. It is also to be granted that an efficient cause, which is not by its very existence always ready for the production of an effect, must exist before its effect. But it is in no way evident that cause and effect cannot be simultaneous, when the cause by its mere existence is ever ready to act. Now creation is an instantaneous effect, and God by His unchangeable and infinitely powerful Will is always able to produce every effect conceivable. The conclusion, then, of this first argument cannot be granted as evident.
102. Second Argument. Creation is production out of nothing. But a creature which exists from eternity has been always something. Consequently such a creature cannot be said to have been produced out of nothing; in other words, it cannot really be a creature.
Answer. The meaning of the phrase, "Creation is production out of nothing," is this: the created being is nothing in itself, but owes its whole existence to the will of its Creator, who has not produced it by the change of any substratum, but has called it into existence by a free act of His omnipotent Will. From this it does not follow that the created being cannot have been called into existence from eternity. If a creature has existed always, it has always been something through the exercise of creative power, but it has never been something in virtue of its own essence.
103. Third Argument. Every finite being must be under all aspects infinitely distant from the perfection of God, the one infinite Being. But on the hypothesis of an eternal creation this is not true, because a creature produced from eternity is equal at least in duration to God.
Answer. We grant the major, but deny the minor of this argument. By the very fact that the duration of a creature is contingent and continually dependent upon God's free-will, it is infinitely less perfect than the duration of God, who continues in existence with absolute necessity by virtue of His own essence.
104. Fourth Argument. Succession from eternity is impossible. But succession belongs to the nature of every creature. Every creature which exists in the moment A can cease to exist in the following moment B. This could not hold if the duration of the creature in the moment B were not really different from its duration in the moment A. But really different durations following one another constitute a succession of durations.
Answer. We grant that succession from eternity is impossible. We do not deny that succession belongs to the nature of every actually existing creature; but we say that it is not evident that it must belong to the nature of every possible creature. Though great scholastic philosophers, St. Bonaventure,{30} the Conimbricenses,{31} and others, held that even in the duration of a created spiritual substance there is succession, by reason of the contingency of all created being; still that position is open to doubt. The full reason why a spirit existing now can presently cease to be is not any tendency to nothingness inherent in the spirit itself, but it is the absolute dependence of the creature upon the power of God, who preserves it in being, and who by withdrawing His preserving influence could, if He pleased, let it fall back into nothingness. We have, therefore, no clear evidence that in the substance of a spiritual creature there is succession.
But it may be asked, Is there not necessarily succession in its operations? Or is any created spirit possible which can operate without change in itself? If that is an impossibility, every created spirit must necessarily have a beginning, for a spirit cannot be wholly without operation. This reason goes a long way to show that the creation of a spirit from eternity, and a fortiori the creation of matter from eternity, is absolutely impossible, because an existence from eternity can hardly be other than a changeless existence; and we cannot conceive either matter or spirit to have existed from eternity without change. We are not inclined to think that such a created existence is possible; but neither have we a certain reason for saying that it is intrinsically repugnant. We must, then, conclude by saying that the impossibility of eternal creation is not certainly proved.
{29} St. Thomas, Sum. Theol. 1a. q. 46. art. 2. To understand St. Thomas properly, the reader must ponder what he here says in answer to the eighth objection.
{30} In l. 2. dist. d. 2. a. 1. q. 3.
{31} In l. 4. Phys. c. 14. p. 2. Cf. Pesch, Phil. Nat. n. 502.