Many a man has cherished for years as his hobby some vague shadow of an idea, too meaningless to be positively false.

All the evolution we know of proceeds from the vague to the definite.

The pragmatist knows that doubt is an art which has to be acquired with difficulty.

Bad reasoning as well as good reasoning is possible; and this fact is the foundation of the practical side of logic.

In the matter of ideas the public prefer the cheap and nasty.

The universe ought to be presumed too vast to have any character.