“Atheism is without God. It does not assert no God. The atheist does not say that there is no God, but he says 'I know not what you mean by God. I am without the idea of God. The word God to me is a sound conveying no clear or distinct affirmation. I do not deny God, because I cannot deny that of which I have no conception, and the conception of which by its affirmer is so imperfect that he is unable to define it for me.”