Nobody spends any money on smallpox unless they worry about a bio-terrorist recreating it.

Like my friend Warren Buffett, I feel particularly lucky to do something every day that I love to do. He calls it "tap dancing to work."

Nobody spends any money on smallpox unless they worry about a bio-terrorist recreating it.

[Melinda Gates] is a lot of fun to work with. There's some of the people skills that she's better at and cares about more. It'd be a mistake not to think of her as very numerical and interested in the science. I enjoy, if I get ahead of her, say, understanding the immune system, then we can spend a few hours, where I'm going through how amazing it is and interesting, and how that affects our creating new products, so I've always had a partner.

People don't want lots and lots of single purpose devices. They do not want to have to learn how to set up something for photos, another thing for music, another thing for video.

As we get robots becoming more sophisticated, I think we should worry sooner rather than later on how much they could take over, but I think it'll mostly be a positive thing. In terms of deadlines it won't be any worse than nuclear weapons.

We have completely eradicated smallpox; we have almost eradicated polio. That's the miracle of vaccines, which is even greater than that of antibiotics.