My wife thinks she's better than me at puzzles. I haven't given in on that one yet.

There's always been a lot of information about your activities. Every phone number you dial, every credit-card charge you make. It's long since passed that a typical person doesn't leave footprints.

I don't have a magic formula for prioritizing the world's problems.

If empathy channels our optimism, we will see the empathy and the diseases and the poor school. We will answer with our innovations and we will surprise the pessimists.

The concept of this so-called "TerraPower reactor" is that you, in the same reactor, you both burn and breed. So, instead of making plutonium and then extracting it, we take uranium - the 99.3 percent that you normally don't do anything with - we convert that, and we burn it.

You know, I'm a big believer in touch and digital reading, but I still think that some mixture of voice, the pen and a real keyboard - in other words a netbook - will be the mainstream on that.

Energy is actually harder; it takes more time to get a product, but if you do it's a very, very big market and the constraints of doing that in a clean way are more obvious all the time.