The greatest task before civilization at present is to make machines what they ought to be, the slaves, instead of the masters of men.

All the art of living lies in a fine mingling of letting go and holding on.

It is becoming clear that the old platitudes can no longer be maintained, and that if we wish to improve our morals we must first improve our knowledge.

Pain and death are part of life. To reject them is to reject life itself.

Of woman as a real human being, with sexual needs and sexual responsibilities, morality has often known nothing.

The romantic embrace can only be compared with music and with prayer.