Language is the most imperfect and expensive means yet discovered for communicating thought.

A great idea goes through three stages on its way to acceptance: 1) it is dismissed as nonsense, 2) it is acknowledged as true, but insignificant, 3) finally, it is seen to be important, but not really anything new.

All natural goods perish. Riches take wings; fame is a breath; love is a cheat; youth and health and pleasure vanish.

Earnestness means willingness to live with energy, though energy bring pain.

Science as such assuredly has no authority, for she can only say what is, not what is not.

The highest flights of charity, devotion, trust, patience, bravery to which the wings of human nature have spread themselves, have been flown for religious ideals.

To be fertile in hypotheses is the first perquisite of creativity and to be willing to throw them away the moment experience contradicts them is the next.