The Cosmological and Ontological Arguments: How Saint Thomas Solved the Kantian Problem

Abstract

Let us call the Dependency Theses (DT) the view, first stated by Kant, that certain versions of the cosmological argument depend on the ontological argument. At least two different reasons have been given for the supposed dependence. Given the DT, some of Aquinas' views about God's essence, and about our knowledge of God's existence, can seem, at least at first, to be inconsistent. I consider two different ways of defending Aquinas against this suspicion of inconsistency. On the first defence, based on a widespread understanding of his notion of ‘necessary being’, Aquinas' views fall outside the scope of the DT. The success of this defence is doubtful. There is, however, another defence to be found in Aquinas' work, one directed not to avoiding, but actually to rejecting, the DT. In this second defence, the DT is not a correct assessment even of those views that do fall within its scope. Its success means that Aquinas had available a principled refutation of the DT some five hundred years before it was first formulated.