Truth in our ideas means their power to work.

Plasticity, then, in the wide sense of the word, means the possession of a structure weak enough to yield to an influence, but strong enough not to yield all at once. Each relatively stable phase of equilibrium in such a structure is marked by what we may call a new set of habits.

We are proud of a human nature that could be so passionately extreme, but we shrink from advising others to follow the example.

... if we take the universe of 'fitting,' countless coats 'fit' backs, and countless boots 'fit' feet, on which they are not practically fitted; countless stones 'fit' gaps in walls into which no one seeks to fit them actually. In the same way countless opinions 'fit' realities, and countless truths are valid, tho no thinker ever thinks them.

To kill time is not murder, it's suicide.

Good-humor is a philosophic state of mind; it seems to say to Nature that we take her no more seriously than she takes us. I maintain that one should always talk of philosophy with a smile.

It is as if there were in the human consciousness a sense of reality, a feeling of objective presence, a perception of what we may call something there, more deep and more general than any of the special and particular senses by which the current psychology supposes existent realities to be originally revealed.