The only big companies that succeed will be those that obsolete their own products before somebody else does.

If somebody is working on a new medicine, computer science helps us model those things. We have a whole group here in Seattle called the Institute for Disease Modelling that is a mix of computer science and math-type people, and the progress we're making in polio or plans for malaria or really driven by their deep insights.

We have two other countries, Pakistan and Afghanistan - again it's the instability that is a problem there. So over the next several years, we expect to drive the number of [polio] cases back down to zero because that is likely to be the second disease after smallpox that we completely eradicate.

Really advanced civilization is based on advances in energy.

Banking is necessary - banks are not.

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.

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.