The cold war is over, but cold war thinking survives.

The most terrifying moment in my life was October 1962, during the Cuban Missile Crisis. I did not know all the facts - we have learned only recently how close we were to war - but I knew enough to make me tremble.

Indeed, the whole human species is endangered, by nuclear weapons or by other means of wholesale destruction which further advances in science are likely to produce.

We are told that the possession of nuclear weapons - in some cases even the testing of these weapons - is essential for national security. But this argument can be made by other countries as well.

When the START 2 treaty has been implemented - and remember it has not yet been ratified - we will be left with some 15,000 nuclear warheads, active and in reserve. Fifteen thousand weapons with an average yield of 20 Hiroshima bombs.

But the first the general public learned about the discovery was the news of the destruction of Hiroshima by the atom bomb. A splendid achievement of science and technology had turned malign. Science became identified with death and destruction.

I saw science as being in harmony with humanity.