If, as Kant claimed, we have failed to prove the existence of a material world external to ourselves, how can we possibly prove the existence of an immaterial God? In this brief exposition Dr. Winthrop links and solves both problems, starting with the meaning of existence itself. Arguing from systems theory, he shows that both God and the World are marked by a common testable signature of existence, X. Because X is corroborated empirically, it follows...