There is separation of colored people from white people in the United States. That separation is not a disease of colored people. It is a disease of white people. I do not intend to be quiet about it.
The scientist finds his reward in what Henri Poincare calls the joy of comprehension, and not in the possibility of application to which any discovery may lead.
In a healthy nation there is a kind of dramatic balance between the will of the people and the government, which prevents its degeneration into tyranny.
We come now to the question: what is a priori certain or necessary, respectively in geometry (doctrine of space) or its foundations? Formerly we thought everything; nowadays we think nothing. Already the distance-concept is logically arbitrary; there need be no things that correspond to it, even approximately.
Science has gone a long way toward helping man to free himself from the burden of hard labor; yet, science itself is not a liberator. It creates means, not goals. It is up to men to utilize those means to achieve reasonable goals.
A theory is the more impressive the greater the simplicity of its premises is, the more different kinds of things it relates, and the more extended its area of applicability.