S. G. Belknap at The Point:
James never stopped short in an exploration or an argument—and for him that meant never stopping short of the biggest question: the religious one. His thinking of the late 1890s kept pushing in this direction, culminating in the Gifford Lectures delivered in Edinburgh in 1901 and 1902, the lectures known to posterity as The Varieties of Religious Experience. James felt that the question of this world and the other world was somehow decisive for all of us, whichever way we answered it. And that included a whole lot of answers for someone like William James—attender of séances, consulter of mediums and all-around junkie for experience. In “The Will to Believe,” James is mostly interested in leveling the playing field vis-à-vis his skeptical colleagues. When it comes down to it, he wonders, why can’t we just go ahead and will the belief in God? The stern-minded skeptic is happy to object: we have no evidence for it. James replies: we have no evidence against it. The skeptic concedes, and objects again: well, then, I’ll wait until we have decisive evidence one way or the other. William James: to spend a life in indecision is no different from choosing against it; for example, if you have no decisive evidence that a potential career is best for you, you can’t just delay your decision until you die. The skeptic: but religion is not like that. William James: why not?
more here.