Abstract

Having undertaken several attempts in the field of rational theology, Kant argued in the Critique of Pure Reason that all theoretical proofs for God's existence are in principle doomed to failure, and declared moral theology to be the sole goal of reason's efforts in this field.In this essay I try to show that after the Critique of Pure Reason, Kant's moral theology underwent a development and transformation similar to that undergone by his rational theology before the first Critique.Tracing the development of Kant's doctrine of God as a postulate of practical reason from the first Critique to the Opus postumum, I maintain that Kant offered at least four different arguments for why it is necessary for practical reason to postulate God's existence, only to conclude that none of them establishes its conclusion. In the Opus postumum, the classical doctrine of the postulates of pure reason is finally laid to rest. In the end, for Kant, ethics and religion coincide