Aquinas’s Aristotelian and Dionysian Definition of ‘God’

The Thomist 69 (2005): 203-50 AQUINAS'S ARISTOTELIAN AND DIONYSIAN DEFINITION OF 'GOD' DAVID B. TwETIEN Marquette University Milwaukee, Wisconsin I. AN ALTERNATIVE SOLUTION TO A FAMILIAR OBJECTION AGAINST THE FIVE WAYS READERS OF THOMAS AQUINAS have long quarreled over how to address the inadequacy they sense in his onclusions in the 'five ways'. If, as Gilson famously held, to prove the 'Christian God' is to prove the creator,1 why does not each of Thomas's five ways explicitly conclude to the creator of the world? Without such a conclusion, how can we be satisfied with the 'God' at which a given 'way' purportedly arrives? Four main answers to this question can be found. First is Gilson's original answer, developed by Joseph Owens: each of Aquinas's five ways must be reinterpreted in light of his doctrine of existence so as to conclude, in fact, to the first cause of esse.2 1 Etienne Gilson, The Spirit ofMediaeval Philosophy, trans. A. H. C. Downes (NewYork: Scribner's, 1936), 72-73: "Whoever undertakes to prove the existence of God per ea quae facta sunt undertakes in advance to prove His existence as Creator of the Universe; in other words he is committed to the view that ... the idea of creation is necessarily implied in every demonstration of the existence of the Christian God." See also Joseph Owens, St. Thomas Aquinas on the Existence of God: Collected Papers ofJoseph Owens, C.Ss.R., ed. J. Catan (Albany: State University of New York Press, 1980), 142-43, 156, 163. 2 Etienne Gilson, Le Thomisme: Introduction ala philosophiede saintThomas d'Aquin, 4th ed. (Paris: Vrin, 1942), 111, 116-17; Joseph Owens, An Elementary Christian Metaphysics (Milwaukee: Bruce, 1963), 341-51; idem, St. Thomas Aquinas on the Existence ofGod, 16263 , 173-86. 203 204 DAVID B. TWETIEN For Owens, then, the favored proof is that of Aquinas's De ente et essentia, to which all other arguments must be reduced if they are to succeed.3 But what if such a reinterpretation fails, as Gilson himself came to admit?4 A second answer holds that for Aquinas the proof of God's existence is only completed at some stage subsequent to the five ways, once many other properties have been established, such as that God is a personal being, or that there is only one God.5 In the Summa Theologiae, for example, questions 2-11 can be seen as successively establishing a series of properties that, when taken together, comprise what it means to be God. Alternatively, according to a third commonly proposed answer, Aquinas never intended a purely philosophical proof for the existence of •cod' as such in the first place.6 To pose the question "Does God exist?" is to presuppose a God believed in by faith; the question belongs, therefore, to theology, not philosophy .7 Finally, the fourth answer insists that Aquinas failed in his project, and the sooner Thomists realize this fact, the better. Fernand Van Steenberghen has argued forcefully that the failure of Aquinas's five ways lies in the uncritical 'nominal definition' with which they begin, that is, in the definition of the term·cod'.8 Nominal definitions such as 'prime mover' or 'necessary 3 Owens, Christian Metaphysics, 349-51. Of course, Gilson came to deny that the De ente contains a proof of God's existence; see Etienne Gilson, "La preuve du 'De ente et essentia'," Doctor Communis 3 (1950): 257-60. 4 Etienne Gilson, Le Thomisme, ~ed. (Paris: Vrin, 1965), 7, 93-94, 97. 5 See especially William Lme Craig, The Cosmological Argument from Plato to Leibniz (London: Macmillan, 1980), 159, 170; Norman Kretzmann, The Metaphysics of Theism: Aquinas' Natural Theology in «Summa contra gentiles I" (Oxford: Oxford University Press, 1997), 85-89, 112-13, 169. 6 See Charles J. Kelly, "The Intelligibility of the Thomistic God," Religious Studies 12 (1976): 347-64, at356-58; LuborVdecky,Aquinas'FiveArguments in theSummaTheologiae la 2, 3 (Kampen, Netherlands: Kok Faros, 1994), 19, 22, 37-38, 41-44, 47. 7 Antonin Finili, "Is There a Philosophical Approach to God?" Dominican Studies 4 (1951): 80-101; Vincent Edward Smith, "The Prime Mover: Physical and Metaphysical Considerations," Proceedings ofthe...