The world that we must seek is a world in which the creative spirit is alive, in which life is an adventure full of joy and hope, based rather upon the impulse to construct than upon the desire to retain what we possess or to seize what is possessed by others.

It is the things for which there is no evidence that are believed with passion.

The first essential character [of civilization], I should say, is forethought. This, indeed, is what mainly distinguishes men from brutes and adults from children.

I did not know I loved you until I heard myself telling so, for one instance I thought, "Good God, what have I said?" and then I knew it was true.

Whether science-and indeed civilization in general-can long survive depends upon psychology, that is to say, it depends upon what human beings desire.

What men really want is not knowledge but certainty.

Few people can be happy unless they hate some other person, nation, or creed.