The use of force stands in need of control by a public neutral authority, in the interests of liberty no less than of justice. Within a nation, this public authority will naturally be the state; in relations between nations, if the present anarchy is to cease, it will have to be some international parliament.

Three passions, simple but overwhelmingly strong, have governed my life: the longing for love, the search for knowledge, and unbearable pity for the suffering of mankind.

Aristotle could have avoided the mistake of thinking that women have fewer teeth than men, by the simple device of asking Mrs. Aristotle to keep her mouth open while he counted.

Be isolated, be ignored, be attacked, be in doubt, be frightened, but do not be silenced.

As a lover of truth, the national propaganda of all the belligerent nations sickened me. As a lover of civilization, the return to barbarism appalled me.

Civilized people cannot fully satisfy their sexual instinct without love.

Order, unity, and continuity are human inventions, just as truly as catalogues and encyclopedias.