Thomas Aquinas' use of metaphysics: Natura, suppositum and esse

This thesis examines Aquinas' use of metaphysics within revealed theology. This is pursued in terms of a two-fold project. The first aspect of this project is methodological. Scholars such as Etienne Gilson and Mark Jordan have held that by incorporating traditional philosophical concepts and arguments into Christian theology, Aquinas thereby transforms their meaning in light of theological categories. To the contrary, I show that Aquinas makes use of philosophy and metaphysics as starting points for understanding revealed mysteries, proceeding in an Aristotelian fashion by explaining the unknown in terms of what is better known to us.; The second aspect of this project is to examine how Aquinas applies this method in theological practice. To this end the thesis examines a series of cases where Aquinas makes substantive use of metaphysics in the context of his Christology. These “case studies” show in detail how Aquinas makes use of philosophy within his theology and serve to corroborate my interpretation of Aquinas' methodology.