It's OK for China to invent cancer drugs that cure patients in the United States. We want them to catch up. But as the leader, we want to keep setting a very, very high standard. We don't want them to catch up because we're slowing down or, even worse, going into reverse.

The most amazing philanthropists are people who are actually making a significant sacrifice.

I was announcing to the public, in 2006, that I'd be leaving Microsoft in a couple of years and focusing full-time on the foundation. That was the time at which we went back to New York and Warren [Buffett] announced these gifts to a number of foundations, with a very high percentage of it going to us and basically doubling our capacity.

I have a particular relationship with Vinod Khosla because he's got a lot of very interesting science-based energy startups.

When I was in college, for the games of that era, I was as hard core as anyone was. I wouldn't say I outgrew it, but you always have to have a finite number of addictions.

It’s been proven that of all the interventions to reduce poverty, improving agricultural productivity is the best.

The next big invention that will change the way we live should be things like ways of generating energy like electricity.