Software substitution, whether it's for drivers or waiters or nurses ... it's progressing. ... Technology over time will reduce demand for jobs, particularly at the lower end of skill set. ... 20 years from now, labor demand for lots of skill sets will be substantially lower. I don’t think people have that in their mental model.

Often you have to rely on intuition.

The U.S. and Canada are two generous governments and we reach out and partner with anyone who believes in foreign aid.

The scientific understanding of some of these [childhood] diseases is advancing quite rapidly. There's some things like premature birth or nutrition, first day deaths that we need a lot more insights so that we can build the tools to solve those problems.

One thing I've always loved about the culture at Microsoft is there is nobody who is tougher on us, in terms of what we need to learn and do better, than the people in the company itself. You can walk down these halls, and they'll tell you, 'We need to do usability better, push this or that frontier.'

With world health, every life you save is a wonderful thing, so it's not this question of whether you solve it or you don't. The chance of completely solving the problems has long odds. But really, the thing is that you get to save the first child, the second child, the third child. You can just feel good about that.

In software you can't really add people and expect to get more done, because their ability to understand the program and what's going on it would require so much investment and all their work would require so much review that you'd be more likely to slow things down.