Above all remember your humanity.

But scientists on both sides of the iron curtain played a very significant role in maintaining the momentum of the nuclear arms race throughout the four decades of the Cold War.

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.

Whatever system of governance is eventually adopted, it is important that it carries the people with it. We need to convey the message that safeguarding our common property, humankind, will require developing in each of us a new loyalty: a loyalty to mankind. It calls for the nurturing of a feeling of belonging to the human race. We have to become world citizens.

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.

From my earliest days I had a passion for science.