I turned 65 last year, and each year I get more and more interested in human health. For most people it happens around age 50, but I've always been a slow learner. It's critical in terms of the cost of health care.

I've had a very unusual background in science - not the usual route of planning on being a scientist from age 3. I think my story shows that success is more about personal motivation and determination than it is about where you were born or what your economic status was.

In the past, geneticists have looked at so-called disease genes, but a lot of people have changes in their genes and don't get these diseases. There have to be other parts of physiology and genetics that compensate.

My early years were hardly a model of focus, discipline, and direction. No one who met me as a teenager could have imagined my going into research and making important discoveries. No one could have predicted the arc of my career.

Not enough books focus on how a culture responds to radically new ideas or discovery. Especially in the biography genre, they tend to focus on all the sordid details in the life of the person who made the discovery. I find this path to be voyeuristic but not enlightening.

It was only in the second year of my Ph.D. that I started acting. I wasn't in school plays or anything; I was in bands, but I wasn't cool. There's no such thing as a cool physics person, is there?

There is actually a fair amount of money being put behind science today.

I have a funny mental framework when I do physics. I create an imaginary audience in my head to explain things to - it is part of the way I think. For me, teaching and explaining, even to my imaginary audience, is part of the process.