>Do you need to be willing to risk your reputation and pursue crazy ideas? Is that what leads to great breakthroughs? >>First of all, it helps to be ignorant.

>Do you need to be willing to risk your reputation and pursue crazy ideas? Is that what leads to great breakthroughs? >>First of all, it helps to be ignorant. The time when I did my best work was when I was most ignorant. Knowing too much is a great handicap. Especially if you’ve been teaching for some years, things get so fixed in your mind and it’s impossible to think outside the box. I was in the lucky position of jumping into physics without ever having taken any courses in physics. I’d only been a pure mathematician up to that point. >Is the great scientist also naturally subversive? >>Yes, undoubtedly. You’ve got to destroy what exists in order to build something new. You need good taste, of course. If you destroy indiscriminately, it doesn’t help at all. That’s where intuition comes in—what parts of the old building should be taken down. >Is physics a young person’s game? It seems that most great discoveries are made by people under 40 or even under 30. >>That is true in theoretical physics. Experimenters can keep going much longer and sometimes stay very productive into old age. That’s a very different game. For theoretical physics, I suppose you need to be ignorant. After a while, you get so attached to things as they are. I find this pretty fascinating. I was wondering why people who make something really impressive tend to not repeat that, or they basically only make variations on the original. Be they musician, painter, composer, mathematician, scientist, computer scientist, etc. It's not true for all, but it does seem to describe many successful people. Though, they already made one great feat, so it makes sense for there to just be one.