291. Proofs of the Existence of God. -- With the exception of a few erratic geniuses of the epoch of decadence, all scholastics have unanimously held that the study of the contingent universe yields (a posteriori) proofs of the existence of God. They emphasize the Aristotelian proof of the Prime Mover: the actual is prior to the potential; first absolutely comes the Perfect Being, without which no single actual being would be realizable.^{1} Many other proofs are drawn from St. Augustine, but not all scholastics admit the favourite proof of the African philosopher, drawn from the universality and immutability of first principles (100). St. Thomas rejects St. Anselm's "ontological" reasoning. Indeed we may say that all the great scholastics reject it when we remember the reservations made by St. Bonaventure, the strongest disciple of Anselm among the thirteenth-century doctors^{2} (cf. 255).

{1} G. GRUNWALD, Geschichte der Gottesbeweise in Mittelalter bis zum Ausgang der Hochscholastik (Beitr. z. Gesch. d. Philos., etc., Münster, 1907). Cf. monograph by BAEUMKER in his work on Witelo (see below).

{2} "We do indeed find in the great scholastics of the thirteenth century, teachings which partly imply the viewpoint of St. Anselm. But we always find them qualified with reservations which remove the principal defect of the latter" (DOMET DE VORGES S. Anselme, p. 295).