Faith is a matter of the strength of behavior resulting from contingencies which have not been analyzed. Orthodox creedal behavior, in the sense of behavior conforming to laws, is very different from the experiential result of a mystical experience. It has often been said, in fact, that proofs of the existence of God are detrimental to faith, because they supply reasons for a belief that would otherwise be more highly valued as intuitive

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Newton could hold a problem in his mind for hours and days and weeks until it surrendered to him its secret. Then, being a supreme mathematical technician, he could dress it up, how you will, for the purposes of exposition, but it was his intuition which was preeminently extraordinary — “so happy in his conjectures,” said de Morgan “as to seem to know more than he could possibly have any means of proving"

As against solipsism it is to be said, in the first place, that it is psychologically impossible to believe, and is rejected in fact even by those who mean to accept it. I once received a letter from an eminent logician, Mrs. [Dr.] Christine Ladd Franklin, saying that she was a solipsist, and was surprised that there were no others. Coming from a logician, this surprise surprised me. The fact that I cannot believe something does not prove that it is false, but it does prove that I am insincere and frivolous if I pretend to believe it. Cartesian doubt has value as a means of articulating our knowledge and showing what depends on what, but if carried too far it becomes a mere technical game in which philosophy loses seriousness. Whatever anybody, even I myself, may argue to the contrary, I shall continue to believe that I am not the whole universe, and in this every one will in fact agree with me, if I am right in my conviction that other people exist