The Demonstration of God’s Existence

THE DEMONSTRATION OF GOD'S EXISTENCE By MoRTIMER J. ADLER I I CAME upon the work of Jacques Maritain during the early years of my study of St. Thomas. I can express my debt of gratitude to him as a teacher in no better way than by saying that he taught me how to read St. Thomas formalissime .1 The manner and spirit of his discipleship to St. Thomas shows that allegiance to an intellectual tradition need not blind one to the limitations of the past, nor relieve one from facing the exigencies of the present. Not merely by his insistence on the necessity for stripping "the great truths of antiquity of the errors which grow parasitically on them," 2 but by his own re-thinking of traditional positions does he show us how to disengage philosophical truths from the adventitious imagery of an historical culture, be it ancient or mediaeval, and how to exorcise irrelevant errors of fact.8 ' " Rien de plus tragique que ces glissements de !'intelligence, quand elle passe insensiblement d'un principe tres eleve formellement vrai a une application ou materialization menteuse; on trouve beaucoup de ces glissements chez les Grecs, c'est pourquoi les scolastiques disaient qu'il importe toujours d'entendre Aristote fOT'I'Tl-Ulissime" (Questions de Conscience, Paris, 1988: p. 99). 9 Scholasticism and Politics, New York, 1940: p. 189. 8 " A sound philosophy can dispense with the particular system of scientific explanations of which it makes use in accordance with the state of science at a particular epoch, and if that system were one day proved false, the truth of that philosophy would not be affected. Only its language and the sensible illustrations with which it clothes its truths would require modification. . . . From what has been said we can understand why the purely scientific mistakes to be found in the older statements of Aristotelian and Thomistic philosophy, statements which inevitably bear the stamp of the scientific beliefs of their period, do nothing to discredit the truth of that philosophy" (An Introduction to Philosophy, New York, 1980: pp. 120-!n). And he adds in a footnote on p. 122: "The 'crime' of the decadent Scholastics of the sixteenth and seventeenth centuries was that they believed, and made others believe, that the philosophy of Aristotle and St. Thomas was in this sense bound up with the mistakes of ancient science, of which it is in 188 THE DEMONSTRATION OF GOD'S EXISTENCE 189 My study of the philosophy of St. Thomas began twenty years ago with the reading of the question on God's existence in the Summa Theologica. It was then that the vocation of the philosopher first became clear to me-not irresponsible poetizing, not system building, not the pretensions of a weltanschauung , but the plain hard work of demonstration. Unless the philosopher solves problems by laying adequate analytical foundations for demonstration and, in the light thereof, by proving conclusions from self-evident premises, he does nothing. Though the major part of his own work was theological/ St. Thomas has been for me the exemplar of philosophical method. Nevertheless, it seems to me that, in some instances, more work remains to be done on proofs which St. Thomas advanced . A case in point is provided by his arguments for God's existence. What once seemed clear has, in the light of fuller study, become problematic. I am aware that I am not the first to have encountered difficulties concerning the probative force of the five ways of demonstrating God's existence. Cajetan indicates some of the difficulties by his contention that these arguments do not conclude directly to the existence of the God of revelation, hut require interpretation in the light of analysis to be found in questions of the Summa which follow the question on the existence of God.5 Banez accepts this point of view, but only reality wholly independent." Cf. Degrees of Knowledge, 1938: pp. 58-63, 74-5. Vd. also Scholasticism and Politics, p. 207. • Vd. Contra Gentiles, I, 2. Maritain observes that "in the Middle Ages philosophy was usually treated as an instrument in the service of theology. Culturally, it was not in the state required...