The desire to gain wealth and the fear to lose it are our chief breeders of cowardice and propagators of corruption.

When thoughts do not neutralize an undesirable emotion, action will.

The prescription is that the subject must be made to show new aspects of itself; to prompt new questions; in a word, to change. From an unchanging subject the attention inevitably wanders away.

Marvelous as may be the power of my dog to understand my moods, deathless as his affection and fidelity, his mental state is as unsolved a mystery to me as it was to my remotest ancestor.

The greatest enemy of any one of our truths may be the rest of our truths.

First... a new theory is attacked as absurd; then it is admitted to be true, but obvious and insignificant; finally it is seen to be so important that its adversaries claim that they themselves discovered it.

The most violent revolutions in an individuals beliefs leave most of his old order standing. Time and space, cause and effect, nature and history, and ones own biography remain untouched. New truth is always a go-between, a smoother-over of transitions. It marries old opinion to new fact so as ever to show a minimum of jolt, a maximum of continuity.