Like my friend Warren Buffett, I feel particularly lucky to do something every day that I love to do. He calls it "tap dancing to work."

When you want to do your homework, fill out your tax return, or see all the choices for a trip you want to take, you need a full-size screen.

Harnessing steam power required many innovations, as William Rosen chronicles in the book 'The Most Powerful Idea in the World.'

Our modern lifestyle is not a political creation. Before 1700, everybody was poor as hell. Life was short and brutish. It wasn't because we didn't have good politicians; we had some really good politicians. But then we started inventing - electricity, steam engines, microprocessors, understanding genetics and medicine and things like that. Yes, stability and education are important - I'm not taking anything away from that - but innovation is the real driver of progress.

So we can simulate Richter-10 earthquakes. We simulate 70-foot waves coming into these things. Very cool. We basically say no human should ever be required to do anything, because if you judge by Chernobyl and Fukushima, the human element is not on your side.

I was a kind of hyper-intense person in my twenties and very impatient.

Should there be cameras everywhere in outdoor streets? My personal view is having cameras in inner cities is a very good thing. In the case of London, petty crime has gone down. They catch terrorists because of it. And if something really bad happens, most of the time you can figure out who did it.