Abstract

In order to understand the importance of the demonstrations of God‟s existencein the second quaestio of the Summa Theologiae, we need to follow theguidelines of interpretation that Aquinas himself provides in the chaptersprevious to the account of the five ways.1Otherwise we cannot understand thetext properly. Indeed, we naturally expect universal validity and necessity froman argument labeled as a proof. But things are not as simple as that in the SummaTheologiae. In this paper, I would like to argue that, in order to evaluate thedemonstrations of God‟s existence in the Summa Theologiae, it is necessary tounderstand the idea of scientia, which Aquinas develops in his commentary onAristotle‟s Posterior Analytics. Helpful for my reasoning was John I. Jenkins,Knowledge and Faith in Thomas Aquinas.2In a further step, I would like to turnto the principle of any scientia, the intellect, and elaborate how Aquinas's wholemetaphysics of being can serve as a proof of God's existence