Si Deus est Deus, Deus est: Reflections on St. Bonaventure's Interpretation of St. Anselm's Ontological Argument

SI DEUS EST DEUS, DEUS EST REFLECTIONS ON ST. BONAVENTURE'S INTERPRETATION OF ST. ANSELM'S ONTOLOGICAL ARGUMENT1 The sentence by St. Bonaventure which makes up the title of this lecture and summarizes the core of his defense of St. Anselm's ontological argument, is found in Quaestiones Disputatae de Mysterio Trinitatis.2 It reads: Similiter argui potest: si Deus est Deus, Deus est; sed antecedens est adeo verum, quod non potest cogitan non esse; ergo Deum esse est verum indubitabile.3 It has been held that the dialectics of Anselm's argument has been entirely reduced here so as to make the argument practically disappear altogether.4 The statement, "If God is God, then God exists," seems at first to be a meaningless empty statement which belongs to the non-informative propositions (of which the wellknown "analytic propositions" are only one class, as Wenisch has 1I wish to acknowled the help Mr. Michael Cusick has given me in completing this article. He has proposed various improvements of style and thought, as well as some of the quotes from Bonaventure's text. Mr. Cusick holds a degree in classics and philosophy and has done very good work on the ontological argument. 2De Mysterio Trinitatis I, i, 29. In Doctoris Seraphici S. Bonaventurae Opera omnia, edita studio et cura PP. Collegii a S. Bonaventura, ad Claras Aquas (Quaracchi) ex Typographia Collegii S. Bonaventurae, 10 volumina (1882-1902) vol. 4, p. 48. Wherever the exact work and reference for a Latin phrase of Bonaventure is not given but only [vol. no., page no.], the quote is taken from the abbreviated formulations of Bonaventure's thought in the indexes of the Quaracchi edition, the numbers referring to volume and page of that same edition, where the complete original text can be found. 3Manuscript H reads at the end instead of the last six words: "ergo et consequens." Then it adds: Item nullus potest cogitare, quando fuit, postquam fuit, non fuisse; ergo si in Deo idem esse, fuisse, et fore, nullus potest cogitare Deum non esse; si enim omne, quod non potest cogitari non esse, est verum indubitabile, et Deum esse, ut patet, non potest cogitari non esse: ergo . . . (ibid, notes of editors.) 4On the various opinons on St. Bonaventure's defense of the ontological argument and on the factual content and historical roots of St. Bonaventure's philosophy, see J. F. Quinn, The Historical Constitution of St. Bonaventure's Philosophy (Toronto. Pontifical Institute of Medieval Studies Press, 1973). The most congenial work on Bonaventure's philosophy, however, remains E. Gilson's book (see note 8). Franciscan Studies 52 (1992) 216 JOSEF SEIFERT demonstrated recently).5 The Bonaventurian summary of Anselm's argument seems then to amount to nothing more than: "If a necessarily existing being exists as necessarily existing, this being exists." The attempt of St. Bonaventure to defend the Anselmian argument and to demonstrate that God exists on the mere premise (antecedent) "(If) God is God," seems at first sight to be fraught (even more than Anselm's own formulation) with all the logical flaws with which the ontological argument has been charged by St. Thomas, I. Kant, F. Brentano, to mention just a few of its opponents. The argument as presented by Bonaventure in the quoted passage, "If God is God, God exists," (to be complemented by: "God evidently is God") is a hypothetical-categorical inference of the modus ponens. The antecedent of the hypothetical proposition (the categorical premise of the argument): (If) God is God, is evident only when it is interpreted as a non-informative tautological proposition: (si) Deus est Deus. But while analytical propositions are of course necessarily true, it is difficult to determine in what exactly their truth consists and in which manner their truth has any application to real beings. For, as Kant has shown in his critique of the ontological argument,6 the necessary truth of an analytic (categorical) proposition (which is based on the first logical principles of identity and contradiction) does not state anything about reality categorically but only hypothetically. Therefore the proposition "Deus est Deus" (of which Bonaventure says that it is indubitably self-evident), implies only the conditional evident truth about...