I have been asked whether I would agree that the tragedy of the scientist is that he is able to bring about great advances in our knowledge, which mankind may then proceed to use for purposes of destruction. My answer is that this is not the tragedy of the scientist; it is the tragedy of mankind.

If the thickness is larger than the critical value I can produce an explosion.

A great power imposes the obligation of exercising restraint, and we did not live up to this obligation. I think this affected many of the scientists in a subtle sense, and it diminished their desire to continue to work on the bomb.

If one knows only what one is told, one does not know enough to be able to arrive at a well-balanced decision.

In science it is not enough to think of an important problem on which to work. It is also necessary to know the means which could be used to investigate the problem.

Do your work for six years; but in the seventh, go into solitude or among strangers, so that the memory of your friends does not hinder you from being what you have become.

Don't lie if you don't have to.