Intellectual freedom is the only guarantee of a scientific - democratic approach to politics, economic development, and culture.

For me, the moral difficulties lie in the continual pressure brought to bear on my friends and immediate family, pressure which is not directed against me personally but which at the same time is all around me.

Nothing threatens freedom of the personality and the meaning of life like war, poverty, terror. But there are also indirect and only slightly more remote dangers. One of these is the stupefaction of man (the "gray mass," to use the cynical term of bourgeois prognosticators) by mass culture with its intentional or commercially motivated lowering of intellectual level and content, with its stress on entertainment or utilitarianism, and with its carefully protective censorship.

Do not trust governments more than governments trust their own people.

My present work concerns the problems connected with the theory of elementary particles, the theory of gravitation and cosmology and I shall be glad if I can manage to make some contribution to these important branches of science.

You can't sit on two chairs at once.

International affairs must be completely permeated with scientific methodology and a democratic spirit, with a fearless weighing of all facts, views, and theories, with maximum publicity of ultimate and intermediate goals, and with a consistency of principles.