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.

Above all remember your humanity.

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.

Let me remind you that nuclear disarmament is not just an ardent desire of the people, as expressed in many resolutions of the United Nations. It is a legal commitment by the five official nuclear states, entered into when they signed the Non-Proliferation Treaty.

Long before the terrifying potential of the arms race was recognized, there was a widespread instinctive abhorrence of nuclear weapons, and a strong desire to get rid of them.

This is the reality of nuclear weapons: they may trigger a world war; a war which, unlike previous ones, destroys all of civilization.

Technology is driving us together. In many ways we are becoming like one family. With the global threats resulting from science and technology, the whole of humankind now needs protection. We have to extend our loyalty to the whole of the human race.