What is William James' argument in the "Will to Believe" (in reference to the topic "religious experience")?

To begin with William James’s argument is not a direct argument in favour/against religious experience. He does not argue that religious experience is conclusive proof of God. Rather he is arguing that it is not immoral to believe in God without conclusive proof. Background History: William Kingdom Clifford wrote a book titled “The Ethics of Belief” in 1876. In the paper he wrote “it is wrong always, everywhere, for anyone, to believe anything upon insufficient evidence”. When applying that to religious belief, he argued that “the life of that man is one long sin against mankind”. James wanted to argue that sometimes it is reasonably, almost right to believe something without sufficient evidence; that sometimes it is okay to believe without having all the facts. He wrote “The Will to Believe” in 1896 as a retaliation to Clifford’s conclusions. He outlines his three conditions that an experience needs to have for it to be considered a religious experience: It must be a living option. The experience is something of concern to the individual, and the option presented must be considered as a genuine possibility. For example a person may be concerned about what the point of life is. She may also be agnostic person and see Buddhism as a living, genuine option in a way that belief in the Egyptian sun god Ra could never be. It must be momentous, meaning it must affect your outlook on life and not be a trivial experience you can brush-off.  It is a forced option; you have to decide what the experience means to you despite the lack of evidence. Once a person has an experience like this (fulfilling all three conditions), it therefore doesn’t seem contradictory or wrong to believe in God despite the lack of evidence. The experience increases the probability of God’s existence. A similar example; say a person wanted to ask someone out on a date, but wasn’t sure if they liked them. The person may then look for clues that might suggest the person likes them. If they had enough clues they may become pretty certain on the possibility despite the lack of conclusive evidence. It then wouldn’t seem immoral for them to believe that the other person liked them and therefore they should go ahead and ask them out. Similarly a religious experience may be like the clues, but it would be a life-changing and important experience rather than a simple clue.