"The preservation of peace and the improvement of the lot of all people require us to have faith in the rationality of humans. If we have this faith and if we pursue understanding, we have not the promise but at least the possibility of success. We should not be misled by promises. Humanity in all its history has repeatedly escaped disaster by a hair's breadth. Total security has never been available to anyone. To expect it is unrealistic; to imagine that it can exist is to invite disaster. What we do have in our technological capacities is an opportunity to use our inventiveness, our creativity, our wisdom and our understanding of our fellow beings to create a future world that is a little better than the one in which we live today."

“On May 7, a few weeks after the accident at Three-Mile Island, I was in Washington. I was there to refute some of that propaganda that Ralph Nader, Jane Fonda and their kind are spewing to the news media in their attempt to frighten people away from nuclear power. I am 71 years old, and I was working 20 hours a day. The strain was too much. The next day, I suffered a heart attack. You might say that I was the only one whose health was affected by that reactor near Harrisburg. No, that would be wrong. It was not the reactor. It was Jane Fonda. Reactors are not dangerous.”

“I contributed; Ulam did not. I'm sorry I had to answer it in this abrupt way. Ulam was rightly dissatisfied with an old approach. He came to me with a part of an idea which I already had worked out and difficulty getting people to listen to. He was willing to sign a paper. When it then came to defending that paper and really putting work into it, he refused. He said, "I don't believe in it.”

“A fact is a simple statement that everyone believes. It is innocent, unless found guilty. A hypothesis is a novel suggestion that no one wants to believe. It is guilty, until found effective.”

“At the end of the war, most people wanted to stop. I didn't. Because here was more knowledge. And in the coming uncertain period, with a dangerous man like Stalin around, and our incomplete knowledge, I felt that more knowledge is necessary. Among the people who knew a great deal about the hydrogen bomb, I was the only advocate of it. And that is, I think, my contribution. Not that I invented it, others would have — and others in the Soviet Union did. But I was the one person who put knowledge, and the availability of knowledge, above everything else.”

“My name is not Strangelove. I don't know about Strangelove. I'm not interested in Strangelove. What else can I say?... Look. Say it three times more, and I throw you out of this office.”

“Edward Teller's FBI file”