A scientist should be the happiest of men.

The Vietnamese have a secret weapon. It's their willingness to die beyond our willingness to kill. In effect, they've been saying, You can kill us, but you'll have to kill a lot of us; you may have to kill all of us. And, thank heaven, we are not yet ready to do that.

There are only two possible explanations as to how life arose: Spontaneous generation arising to evolution or a supernatural creative act of God.... There is no other possibility. Spontaneous generation was scientifically disproved 120 years ago by Louis Pasteur and others, but that just leaves us with only one other possibility... that life came as a supernatural act of creation by God, but I can't accept that philosophy because I do not want to believe in God. Therefore I choose to believe in that which I know is scientifically impossible, spontaneous generation leading to evolution.

Our challenge is to give what account we can of what becomes of life in the solar system, this corner of the universe that is our home; and, most of all, what becomes of men-all men, of all nations, colors, and creeds. This has become one world, a world for all men. It is only such a world that can now offer us life, and the chance to go on.

There was a golden period that I look back upon with great regret, in which the cheapest of experimental animals were medical students. Graduate students were even better. In the old days, if you offered a graduate student a thiamine-deficient diet, he gladly went on it, for that was the only way he could eat. Science is getting to be more and more difficult.

I tell my students, with a feeling of pride that I hope they will share, that the carbon, nitrogen, and oxygen that make up ninety-nine per cent of our living substance were cooked in the deep interiors of earlier generations of dying stars. Gathered up from the ends of the universe, over billions of years, eventually they came to form, in part, the substance of our sun, its planets, and ourselves. Three billion years ago, life arose upon the earth. It is the only life in the solar system.

The only use for an atomic bomb is to keep somebody else from using one. It can give us no protection - only the doubtful satisfaction of retaliation...