Recently, a number of prominent scientists and scientifically-oriented philosophers have come out in favor of atheism with respect to the existence of God and the supernatural. Other scientists have come out in support of Christian views of God. But is a categorical claim on the existence or non-existence of a hypothesized entity (or class of entities) consistent with an open-ended and always-revisable characterization of science. After all, as is often proclaimed, hypotheses are never “proven” by science and every scientific conjecture is, at least in principle, open to future revision on the basis of new observations and theoretical innovation. This understanding of science would appear to advocate for religious agnosticism, not atheism. This chapter will explore this apparent tension and attempt to understand whether scientists qua scientists must take a particular stand on the existence of the supernatural.