Deus atque id quod fieri potest

Abstract

Leibniz’s reasoning to demonstrate God's existence is compared with a non-modal argument put forward by G. Mavrodes and some recent modal reformulations of St. Anselm's ontological approach. Leibniz's principle “if the necessary can be, then it is” and St. Bonaventure's (and Aquinas’) “necessity of contingency” are examined along with Kant's pre-critical “foundation of possibility” proof. It is suggested that traditional exemplarism (as that of Augustine) grounds the results of current and Scholastic modal theory, leading to an integrated world-view both Christian and philosophical.