Thinking in its lower grades, is comparable to paper money, and in its higher forms it is a kind of poetry.

Still, whether we like it or not, the task of speeding up the decrease of the human population becomes increasingly urgent.

One can know nothing of giving aught that is worthy to give unless one also knows how to take.

Charm" — which means the power to effect work without employing brute force — is indispensable to women. Charm is a woman's strength just as strength is a man's charm.

It is here [in mathematics] that the artist has the fullest scope of his imagination.

Dancing is the loftiest, the most moving, the most beautiful of the arts, because it is no mere translation or abstraction from life; it is life itself.

There is nothing more fragile than civilization.