God

In Book 2 of On Free Choice of the Will Augustine offers an argument for the existence of God. It is a purely a priori argument. Although it is not as important as Anselm’s famous a priori argument in his Proslogion, it is not without interest. Augustine gets his interlocutor to admit that x is God if, and only if, x is more excellent than our minds and nothing is more excellent than x. He then states that truth is more excellent than our minds, perhaps on the ground that truth sits in judgment on our thoughts. He then concludes that either truth itself is God or there is something more excellent that truth and it is God. In either case, God exists.

Although Augustine’s argument for the existence of God does not use Anselm’s expression for God, ‘‘something than which nothing greater can be conceived,’’ Augustine does sometimes use, in other contexts, expressions quite like that of Anselm, who was a professed Augustinian. Thus, for example, in Confessions 7.4.6 he writes: ‘‘Nor could there have been or be any soul capable of conceiving that which is better than you, who are the supreme and highest good.’’

Augustine made important contributions in the project of giving a philosophical account of the divine attributes. But perhaps his most influential contribution to this topic is his espousal of the idea that God is metaphysically simple, so that God is not only, for example, good and wise, God is God’s own goodness and wisdom. Here is a passage on the divine simplicity from On the Trinity:

>  But God is not great by a greatness that is not that which he himself is - as if God were, so to speak, a partaker in greatness when he is great. For in that case greatness would be greater than God. But there cannot be anything greater than God. Therefore, he is great by that greatness which is identical with himself (5.19.11).