Do mystical experiences make it rational to believe in God? A fair number of theistic philosophers have thought so, and, for the mystic who is ignorant of current scientific findings, perhaps that conclusion is correct. But the ignorant are not best qualified to judge: let us see how science might inform judgment. Here I will focus most particularly on the neurological basis of mystical experiences (MEs). It might initially seem that the evidence for such a basis is theologically benign—neutral on the question whether MEs may reasonably be considered veridical perceptions of the divine. I shall argue that this is a mistake.