Shared Necessity & Free Creation

Question #9: If God’s creative act and His existence share the same necessity (cf. ST I.45.2), does this mean that, from a Catholic perspective, God could not do otherwise, thus undermining free creation?


In Summa Theologiae I.45.2, St. Thomas Aquinas affirms that God’s creative act, being one with His will and essence, has the same intrinsic necessity as God’s own being. At face value, this could suggest that if God’s act to create is “as necessary” as God Himself, then God could not have done otherwise–undermining the Church’s teaching on free creation. However, Catholic tradition, following Aquinas, clarifies that such “necessity” applies only to God’s internal reality, not to the created effect itself.

1. Necessity in God vs. Contingency of Creation

When Aquinas says God’s creative act has the same necessity as His existence, he means there is no division between God’s essence and His act of will. God is simple (no composition), so His will to create cannot be a “separate part” in Him that could be added or removed. In that sense, any act God performs is as “necessary” as God is–internally–because it is not distinct from His very being. But that does not imply creation, as an effect, exists necessarily. Rather, it means that God cannot “begin” or “cease” to will as though He were in time or subject to change.

2. Distinguishing “Necessity of Supposition” from “Absolute Necessity”

Medieval theologians often differentiate between an action that is absolutely necessary and one that follows necessarily “given that God so wills.” In other words, once God eternally wills creation, that will is necessarily part of God’s unchanging identity. But it remains contingent that He willed in the first place. Nothing forced His hand to will a universe. If He had chosen otherwise, there would be no internal contradiction–He would still be God. Hence, the “necessity” of God’s act concerns God’s lack of change, not any constraint forcing Him to create.

3. Freedom and Self-Sufficiency

The key to preserving free creation is recognizing that God’s will is self-sufficient and uncoerced. No external or internal necessity compels God to actualize a universe. He acts from the infinite abundance of His goodness, which the Church understands as a liberal outpouring of love rather than a fulfillment of a need. Thus, while God’s willing is inseparable from His essence, the choice to create was not mandated by that essence. God could just as freely have not willed a world without any impairment to His perfection.

4. Contingency on the Creature’s Side

From creation’s standpoint, it remains entirely contingent–it exists solely because God freely decreed it. That decree is “necessary” in the sense that God cannot alter His eternal will, but it was not necessitated in the first place. Therefore, God “could have done otherwise” without contradiction, preserving the Catholic doctrine of free creation despite God’s act sharing the same necessity as His existence.


(see #7, #8, #24 for more)