It is hard to sell Congress and the American people on foreign aid. Is it harder to do that than it is to sell billionaires on the idea that they should give all their money away.

Really advanced civilization is based on advances in energy.

With a public library card in your hand, you have access to the Internet and a world of opportunities.

I was lucky to be involved and get to contribute to something that was important, which is empowering people with software.

Vaccination is one of the easiest things on the way to development. It's much easier than roads and a great education system. It's very basic. It's one of the first things you want to get right.

Even when things are stable, that's not easy [to work in Africa] because there are not roads, and the weather is tough, the education system hasn't been there. But this is how you get great countries, is step by step.

I really do think cancer will largely be a solved problem. I think most of the infectious diseases like malaria - our foundation is very involved - once we're finishing polio eradication, then starting up this malaria eradication, and getting that done as fast as we can.