The only source of knowledge is experience.

Brief is this existence, as a visit in a strange house. The path to be pursued is poorly lit by a flickering consciousness.

I have little patience with scientists who take a board of wood, look for its thinnest part, and drill a great number of holes where drilling is easy.

It's not that I'm so smart, it's just that I stay with problems longer.

The man with the greatest soul will always face the greatest war with the low minded person.

God casts the die, not the dice.

The finest emotion of which we are capable is the mystic emotion. Herein lies the germ of all art and all true science. Anyone to whom this feeling is alien, who is no longer capable of wonderment and lives in a state of fear is a dead man.