If a single one of these gentlemen is correct, if a believer of any type is right, the essential truth for man, the real drama of life, in comparison with which the secular story of the race, is a puppet-show and the unfolding of the universe is a triviality, is the dialogue of the immortal soul and the eternal God. Yet it seems that there is nothing in the world so hard to discover as this. The theory refutes itself.

The Psychology of Religion (1927), p. 47.