[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.

Our leadership [in Microsoft ] has that - "hey, we are the best in certain ways," and so we get the best people. That any kind of positive dynamic is quite good, so I love what's going on there, it's fun.

There won't be anything we won't say to people to try and convince them that our way is the way to go.

[Africa] is the one continent where you still have a lot more young people than old people. So making sure they're healthy, good nutrition, good education. That'll be important for the world.

The inventory, the value of my company, walks out the door every evening.

Every new change forces all the companies in an industry to adapt their strategies to that change.

I've been very lucky, and therefore I owe it to try and reduce the inequity in the world. And that's kind of a religious belief. I mean, it's at least a moral belief.