You want to ensure people can do it right 99 percent of time. When we have to fire one of our surgical trainees, it is never because they don't have the physical skills but because they don't have the moral skills - to practise and admit failure.

Outsiders tend to be the first to recognize the inadequacies of our social institutions. But, precisely because they are outsiders, they are usually in a poor position to fix them.

If I get hit by a bus tomorrow, my patients will not even be postponed. Another surgeon would step in and take over. The reason to do research and writing is that it at least makes me feel not entirely replaceable. If I didn't write, I don't know if I would do surgery.

Oliver Sacks remains my hero to this day. He was one of the first medical writers I read. The other was Lewis Thomas, who is no longer alive but is just heroic to me.

Our health-care morass is like the problems of global warming and the national debt - the kind of vast policy failure that is far easier to get into than to get out of. Americans say that they want leaders who will take on these problems.