“If I had only known, I would have been a locksmith. ”

“If I had known they were going to do this, I would have become a shoemaker.”

“The release of atomic power has changed everything except our way of thinking ... the solution to this problem lies in the heart of mankind. If only I had known, I should have become a watchmaker. (1945)”

“Only the Catholic Church protested against the Hitlerian onslaught on liberty. Up till then I had not been interested in the Church, but today I feel a great admiration for the Church, which alone has had the courage to struggle for spiritual truth and moral liberty”

“I would not think that philosophy and reason themselves will be man's guide in the foreseeable future; however, they will remain the most beautiful sanctuary they have always been for the select few.”

“Although I have been prevented by outward circumstances from observing a strictly vegetarian diet, I have long been an adherent to the cause in principle. Besides agreeing with the aims of vegetarianism for aesthetic and moral reasons, it is my view that a vegetarian manner of living by its purely physical effect on the human temperament would most beneficially influence the lot of mankind.”

“I have no special talents. I am only passionately curious.”