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.

My interest in astronomy grew from the play 'Space' that I did, where I had to learn where my character was from. I had to study the stars and figure where everything was and how I got here and all of those things.

Our mission at Khan Academy is a free, world-class education for anyone, anywhere, and college readiness is a crucial part of that. We want to help as many students as possible prepare for college and for life, and since the SAT measures preparedness for college, our partnership with the College Board is a natural fit.

In my generation, there was no sushi school, no cooking school, so people have to learn from working.

In 'Chappie,' you see this sort of young robot that's learning through maybe 'deep learning' how to see the world really, look out into the world, and learn step by step. What's so interesting is that with 'Chappie,' you're getting to see how human behavior reacts to artificial intelligence, and I don't think it's always going to be positive.