More and more people are becoming unable to accept traditional [religious] beliefs. If they think that, apart from these beliefs, there is no reason for kindly behaviour, the results may be needlessly unfortunate. That is why it is important to show that no supernatural reasons are needed to make [people] kind and to prove that only through kindness can the human race achieve happiness.

The desire to understand the world and the desire to reform it are the two great engines of progress, without which human society would stand still or retrogress.

Uncertainty in the pressure of vivid hopes and fears is painful, but must be endured if we wish to live without the support of comforting fairy tales.

Continuity of purpose is one of the most essential ingredients of happiness in the long run, and for most men that comes chiefly through their work.

America remained a land of promise for lovers of freedom. Even Byron, at a moment when he was disgusted with Napoleon for not committing suicide, wrote an eloquent stanza in praise of Washington.

The discipline in your life should be one determined by your own desires and your own needs, not put upon you by society or authority.

Why repeat the old errors, if there are so many new errors to commit?