If atomic bombs are to be added as new weapons to the arsenals of a warring world, or to the arsenals of nations preparing for war, then the time will come when mankind will curse the names of Los Alamos and Hiroshima. The people must unite or they will perish.

You can certainly destroy enough of humanity so that only the greatest act of faith can persuade you that what's left will be human.

It is not possible to be a scientist unless you believe that it is good to learn... that it is of the highest value to share your knowledge... with anyone who is interested... that the knowledge of the world, and the power which this gives, is a thing which is of intrinsic value to humanity

I remembered the line from the Hindu scripture, the Bhagavad-Gita... "Now I am become Death, the destroyer of worlds." I suppose we all thought that, one way or another.

[About the great synthesis of atomic physics in the 1920s:] It was a heroic time. It was not the doing of any one man; it involved the collaboration of scores of scientists from many different lands. But from the first to last the deeply creative, subtle and critical spirit of Niels Bohr guided, restrained, deepened and finally transmuted the enterprise.

It is a profound and necessary truth that the deep things in science are not found because they are useful; they are found because it was possible to find them.

We know that the wages of secrecy are corruption. We know that in secrecy error, undetected, will flourish and subvert.