I feel that because I challenge myself so often, sometimes I will fail. This is, to me, the essence of competition — that there will be both winners and losers. But I have great faith in myself that I will turn this loss into something positive.

Failure is the most likely outcome of entrepreneurship. Hence there is absolutely nothing wrong with failure. It is the default outcome. Success on the other hand is rare and unpredictable. Very few find it. However what can help entrepreneurs succeed is when an ecosystem learns from failure.

Well, I'll be honest with you. I was a theoretical physicist but my Ph.D. work was on a problem that was not particularly interesting to me at the time. And I used to subscribe to Scientific American and I found that there were all these wonderful discoveries happening in biology and I also knew that a number of physicists had gone into biology and been successful. So, I decided to switch.

As hard as it's been to come to this decision, I am at peace with it. I have no regrets. I was not supposed to be here in the first place, remember? Not many people believed in my talent and my abilities, yet I found a way to persevere, to prove them (and sometimes myself!) wrong.

Under the stress of the event, we felt, the soldiers' true nature would reveal itself, and we would be able to tell who would be a good leader and who would not. But the trouble was that, in fact, we could not tell. Every month or so we had a "statistics day," during which we would get feedback from the officer-training school, indicating the accuracy of our ratings of candidates' potential. The story was always the same: our ability to predict performance at the school was negligible. But the next day, there would be another batch of candidates to be taken to the obstacle field, where we would face them with the wall and see their true natures revealed. I was so impressed by the complete lack of connection between the statistical information and the compelling experience of insight that I coined a term for it: "the illusion of validity."

Amos and I shared the wonder of together owning a goose that could lay golden eggs – a joint mind that was better than our separate minds. … Some of the greatest joys of our collaboration-and probably much of its success – came from our ability to elaborate each other's nascent thoughts: if I expressed a half-formed idea, I knew that Amos would be there to understand it, probably more clearly than I did, and that if it had merit he would see it. Like most people, I am somewhat cautious about exposing tentative thoughts to others – I must first make sure that they are not idiotic. In the best years of the collaboration, this caution was completely absent.