Some of the problems with Origen’s doctrine of say the pre-existence of souls or necessary creation are precisely two key principle problems in his doctrine elsewhere, however, we shall see he was very consistent. The first is a divine problem. For Origen, God’s essence has no mulitplicity or distinctions. Existence, Will, and Activity are wholly indistinguishable and identical. Since God’s activity is wholly indistinguishable we can say that he is an ‘ever-productive’ agent. To be ever-productive, the divine essence must create, since it has no distinction of being, essence, will and activity. The essence has but one object of willing to choose–it has but one good thing to do. We can therefore say, for God’s essence, true freedom is actually freedom from free choice. Thus, for Origen God was by definition Creator and Almighty:
Accordingly, to prove that God is almighty we must assume the existence of the universe. For if anyone would have it that certain ages, or periods of time, or whatever he cares to call them, elapsed during which the present creation did not exist, he would undoubtedly prove that in those ages or periods God was not almighty, but that he afterwards became almighty from the time when he began to have creatures over whom he could exercise power. Thus God will apparently have experienced a kind of progress, for there can be no doubt that it is better for him to be almighty than not to be so. Now how is it anything but absurd that God should at first not possess something that is appropriate to him and then should come to possess it? But if there was not time when he was not almighty, there must always have existed the things in virtue of which he is almighty; and there must always have existed things under his sway, which own him as their ruler.
(On First Principles, Bk.I C.2,10, trans. G.W. Butterworth)
Origen’s definition of simplicity is therefore accompanied by a dialectic of opposition: If God is simple, he must create; if God is simple, creation is composite. Because of God’s simplicity, creation stands over and against God, for the very purpose that God can be Creator. In other words, “he imagined an endless flow of ages which had to be filled…Any sequence in the divine predicates appeared to him under the form of real temporal change; and therefore, having excluded change, he was inclined to deny any sequence at all to, or interdependence among, those predicates taken as a whole; he asserted more than the mere “co-eternity” of the world with God; he asserted the necessity of the divine self-disclosure ad extra, the necessity of the eternal realization of the fulness and of all the potentialities of Divine power.” (Florovsky, Creation and Redemption, Vol. III, The Collected Works of George Florovsky, p.53) For Origen, “the world was impossible without God, and God was impossible without the world.” (Ibid., pp.55-56). Therefore, for Origen, God cannot choose not create, since such a choice is entagled with a dialectic, which would involve mulitplicity, and given God’s utter perfection, such would by definition be evil and impossible.
The second problem is bound up in the creature. Since, we have just shown that for Origen, God’s freedom is really a freedom from free choice, creation, being composite, must therefore involve choice. This choice, however must precisely be between objects of differing moral value. The creature in its diversity must always have free volition, mutibility, and motion:
the will’s freedom always moves in the direction either of good or evil, nor can the rational sense, that is the mind or soul, ever exist without some movement either good or evil.
(Loc. cit. III, 3,5)
We see in this passage that Origen logically ties personhood to free-choice and motion, but because he cannot disentagle motion and plurality from his definition of free-will as objects dialectically conditioned, this has terrible consequences for the redeemed in the eschaton. With God being absolutely simple, how many objects willing can their be? But one, and Origen has ruled out all diversity or motion in the eschaton for creatures–absorption into the One. However, Origen is not one to give up on the problem. We saw that motion, free-will, and personhood are tied together in his doctrine of free-choice. The redeemed have but one single good object to will, the other option by definition must be evil, which brings us to the second problem: cycles of falls and redemptions:
the soul is immortal and eternal, it is possible that in the many and endless periods throughout diverse and immeasurable ages it may either descend from the Highest Good to the lowest evil or to be restored from the lowest evil to the Highest Good.
(Ibid., III, 1,23)
This is why Origen logically believes in the pre-existence of souls.
My thinking and ideas here were borrowed from Joseph P. Farrell–Free Choice in Saint Maximus the Confessor, Saint Tikhon’s Seminary Press, 1989.