What can I know? What ought I to do? What may I hope?

THERE ARE TWO THINGS that don't have to mean anything, one is music and the other is laughter.

The instruction of children should aim gradually to combine knowing and doing. Among all sciences mathematics seems to be the only one of a kind to satisfy this aim most completely.

The hand is the visible part of the brain.

Religion is too important a matter to its devotees to be a subject of ridicule. If they indulge in absurdities, they are to be pitied rather than ridiculed.

Intuition and concepts constitute... the elements of all our knowledge, so that neither concepts without an intuition in some way corresponding to them, nor intuition without concepts, can yield knowledge.

Better the whole people perish than that injustice be done