In the Life of Darwin by his son, there is related an incident of how the great naturalist once studied long as to just what a certain spore was. Finally he said, "It is this, for if it isn't, then what is it?" And all during his life he was never able to forget that he had been guilty of this unscientific attitude, for science is founded on certitude, not assumption.

It is a fine thing to have ability, but the ability to discover ability in others is the true test.

Every man should have a college education in order to show him how little the thing is really worth.

Theology is an attempt to explain a subject by men who do not understand it. The intent is not to tell the truth but to satisfy the questioner.

If there is any better way to teach virtue than by practicing it, I do not know it.

Dogma is a lie reiterated and authoritatively injected into the mind of one or more persons who believe that they believe what someone else believes.

Our desires always disappoint us; for though we meet with something that gives us satisfaction, yet it never thoroughly answers our expectation.