Belief in the existence of spiritual entities is an integral part of many people’s religious worldview. Angels appear, demons possess, ghosts haunt. But is belief that such entities exist justified? If not, are there conditions in which it would be? I will begin by showing why, once one clearly understands how to infer the best explanation, it is obvious that neither stories nor personal encounters can provide sufficient evidence to justify belief in spiritual entities. After responding to objections to similar (...) arguments I have published in the past, I will go on to show that there is at least an imaginable circumstance in which belief in spiritual entities would be justified but then point out that it is not reasonable to think that such conditions will ever be met. In short, if such entities were real, it would be theoretically possible to demonstrate their existence scientifically, and in doing so, one could make belief in their existence justified. But doing so would require and entail a scientific revolution equivalent to proving that the Earth is flat. (shrink)