"Man is not imprisoned by habit. Great changes in him can be wrought by crisis - once that crisis can be recognized and understood."

"The tragedy of life is in what dies inside a man while he lives - the death of genuine feeling, the death of inspired response, the awareness that makes it possible to feel the pain or the glory of other men in yourself."

"The main failure of education is that it has not prepared people to comprehend matters concerning human destiny."

"He who keeps his cool best wins."

"The one thing I regret was that my work required an enormous amount of my time, and a lot of travel."

"I was well aware of the fact that once you appeared in Doctor Who as something else, you were ruled out for the part of the Doctor: that was a kind of well known thing in the business."

"There is no patriotic obligation to help advance the career of a politician who is otherwise pursuing interests that are fundamentally antithetical to your values. That's not the call of patriotism."

"In our brief national history we have shot four of our presidents, worried five of them to death, impeached one and hounded another out of office. And when all else fails, we hold an election and assassinate their character."