Man has mounted science, and is now run away with. I firmly believe that before many centuries more, science will be the master of men. The engines he will have invented will be beyond his strength to control. Someday science may have the existence of mankind in its power, and the human race commit suicide, by blowing up the world.

I almost think it is the ultimate destiny of science to exterminate the human race.

Mankind ought to end its existence of its own will.

As geological time goes, it is but a moment since the human race began and only the twinkling of an eye since the arts of civilization were first invented. In spite of some alarmists, it is hardly likely that our species will completely exterminate itself. And so long as man continues to exist, we may be pretty sure that, whatever he may suffer for a time, and whatever brightness may be eclipsed, he will emerge sooner or later, perhaps strengthened and reinvigorated by a period of mental sleep. The universe is vast and men are but tiny specks on an insignificant planet. But the more we realize our minuteness and our impotence in the face of cosmic forces, the more astonishing becomes what human beings have achieved.

the possible world that excites me the most-the future we can still have on this one. The misuse of science endangers our civilization, but science also has redemptive powers. It can cleanse a planetary atmosphere overburdened with carbon dioxide. It can set life free to neutralize the toxins that we have scattered so carelessly. In a society that aspires to become a democracy, a conscious and motivated public can will this possible world into existence.

The end of the human race will be that it will eventually die of civilization.

How much good it would do if one could exterminate the human race.

Science, already oppressive with its shocking revelations, will perhaps be the ultimate exterminator of our human species - if separate species we be - for its reserve of unguessed horrors could never be borne by mortal brains if loossed upon the world.

The indwelling deity who presides over the destiny of the race has raised in man's mind and heart the idea, the hope of a new order which will replace the old unsatisfactory order, and substitute for it conditions of the world's life which will in the end have a reasonable chance of establishing permanent peace and well-being.... It is for the men of our day and, at the most, of tomorrow to give the answer. For, too long a postponement or too continued a failure will open the way to a series of increasing catastrophes which might create a too prolonged and disastrous confusion and chaos and render a solution too difficult or impossible; it might even end in something like an irremediable crash not only of the present world-civilisation but of all civilisation.... The terror of destruction and even of large-scale extermination created by these ominous discoveries may bring about a will in the governments and peoples to ban and prevent the military use of these inventions, but, so long as the nature of mankind has not changed, this prevention must remain uncertain and precarious and an unscrupulous ambition may even get by it a chance of secrecy and surprise and the utilisation of a decisive moment which might conceivably give it victory and it might risk the tremendous chance.

Yet the promise of this life is imperiled by the very genius that has made it possible. Nations amass wealth. Labor sweats to create—and turns out devices to level not only mountains but also cities. Science seems ready to confer upon us, as its final gift, the power to erase human life from this planet.

But I felt certain that if the world would stop indulging wars and famines and other perils, it would be possible for human beings to embarrass each other to death. Our self-destruction might take a little longer that way, but I believe it would be no less complete.

The development of full artificial intelligence could spell the end of the human race. We cannot quite know what will happen if a machine exceeds our own intelligence, so we can't know if we'll be infinitely helped by it, or ignored by it and sidelined, or conceivably destroyed by it.

Suppose atomic bombs had reduced the population of the world to one brother and one sister, should they let the human race die out? I do not know the answer, but I do not think it can be in the affirmative merely on the ground that incest is wicked.

Immensely powerful though we are today, it's equally clear that we're going to be even more powerful tomorrow. And what's more there will be greater compulsion upon us to use our power as the number of human beings on Earth increases still further. Clearly we could devastate the world. […] As far as we know, the Earth is the only place in the universe where there is life. Its continued survival now rests in our hands.