(CG 2/23). That God's Action in Creation is not of Physical Necessity, but?... (Book 2: God The Origin of Creatures) (Summa Contra Gentiles) (Aquinas, Thomas, St.)

The will is moved by some apprehension. But God acts by willing. Since then in God there is intellectual apprehension only, and He understands nothing otherwise than by understanding Himself, whom to understand is to be wise (B. I, Chap. LIV), it follows that God works out all things according to His wisdom.

2. Every agent acts in so far as it has within it something corresponding to the effect to be produced. But in every voluntary agent, as such, what corresponds to the effect to be produced is some intellectual presentation of the same. Were there no more than a mere physical disposition to produce the effect, the agent could act only to one effect, because for one physical cause there is only one physical mode of operation (ratio naturalis unius est una tantum). Every voluntary agent therefore produces its effect according to the mode of intellectual operation proper to itself. But God acts by willing, and therefore it is by the wisdom of His intellect that he brings things into being.

3. The function of wisdom is to set things in order. Now the setting of things in order can be effected only through a knowledge of the relation and proportion of the said things to one another, and to some higher thing which is the end and purpose of them all: for the mutual order of things to one another is founded upon their order to the end which they are to serve. But it is proper to intelligence alone to know the mutual relations and proportions of things. Again, it is proper to wisdom to judge of things as they stand to their highest cause. Thus every setting of things in order by wisdom must be the work of some intelligence. But the things produced by God bear an orderly relation to one another, which cannot be attributed to chance, since it (sit not sint) obtains always or for the most part. Thus it is evident that God, in bringing things into being, intended them in a certain order. Therefore His production of them was a work of wisdom.

All this is confirmed by divine authority, for it is said: You has made all things in wisdom (Ps. ciii, 24); and the Lord in wisdom founded the earth (Prov. iii, 19).

Hereby is excluded the error of some who said that all things depend on the absolute will of God, independent of any reason.