 Kant’s practical argument differs profoundly from his contemporaries’ speculative or theoretical arguments for God’s existence. His approach grounds the necessity of believing in God in each person’s practical reason, required to “orient ourselves in thinking” (WOT 8:136–37). According to Kant, belief in God is “a postulate” of practical reason, that is, “a theoretical proposition which is not as such demonstrable, but which is an inseparable corollary of an a priori unconditionally valid practical law” (CPrR 5:122). Although practical arguments cannot provide knowledge of God’s existence, they can provide “moral certainty” of God’s existence (A 828–30/B 856–58; CPrR 5:134, 143; LPDR 28:1011–12). Moral certainty in God’s existence is stronger than the sort of confidence one could obtain from any theoretical argument.