You can't sit on two chairs at once.

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.

I regard the death penalty as a savage and immoral institution that undermines the moral and legal foundations of society. I reject the notion that the death penalty has any essential deterrent effect on potential offenders. I am convinced that the contrary is true - that savagery begets only savagery.

We regard as 'scientific' a method based on deep analysis of facts, theories, and views, presupposing unprejudiced, unfearing open discussion and conclusions. The complexity and diversity of all the phenomena of modern life, the great possibilities and dangers linked with the scientific-technical revolution and with a number of social tendencies demand precisely such an approach, as has been acknowledged in a number of official statements.

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.

Our country, like every modern state, needs profound democratic reforms. It needs political and ideological pluralism, a mixed economy and protection of human rights and the opening up of society.

In 1947 I defended my thesis on nuclear physics, and in 1948 I was included in a group of research scientists whose task was to develop nuclear weapons.