It's because somebody knows something about it that we can't talk about physics. It's the things that nobody knows anything about we can discuss.
Richard P. FeynmanEverybody who reasons carefully about anything is making a contribution ... and if you abstract it away and send it to the Department of Mathematics they put it in books.
Richard P. FeynmanIt appears that there are enormous differences of opinion as to the probability of a failure with loss of vehicle and of human life. The estimates range from roughly 1 in 100 to 1 in 100,000. The higher figures come from the working engineers, and the very low figures from management.
Richard P. Feynman