Abstract
There is an argument for the existence of God from the incompleteness of nature that is vaguely present in Plantinga’s recent work. This argument, which rests on the metaphysical implications of quantum physics and the philosophical deficiency of necessitarian conceptions of physical law, deserves to be given a clear formulation. The goal is to demonstrate, via a suitably articulated principle of sufficient reason, that divine action in an occasionalist mode is needed (and hence God’s existence is required) to bring causal closure to nature and render it ontologically functional. The best explanation for quantum phenomena and the most adequate understanding of general providence turns out to rest on an ontic structural realism in physics that is grounded in the immaterialist metaphysics of theistic idealism.