I really do think cancer will largely be a solved problem. I think most of the infectious diseases like malaria - our foundation is very involved - once we're finishing polio eradication, then starting up this malaria eradication, and getting that done as fast as we can.

We all know that there are these exemplars who can take the toughest students, and they'll teach them two-and-a-half years of math in a single year.

I have to admit that business-type thoughts do sneak into my head: I hope our customers pay us, I hope this stuff is decent, I hope we get it done on time. The little additions and subtractions that one has to do. Take sales, take costs and try to get that big positive number at the bottom.

I believe the government has the right to recover from the heirs to the fortunes of its most successful citizens some portion of those fortunes.

Humanity’s greatest advances are not in its discoveries – but in how those discoveries are applied to reduce inequity.

But the improvements will happen faster and last longer if we can channel market forces, including innovation that's tailored to the needs of the poorest, to complement what governments and nonprofits do. We need a system that draws in innovators and businesses in a far better way than we do today.

Apple has always leveraged technologies that the PC industry has driven to critical mass - the bus structures, the graphics cards, the peripherals, the connection networks, things like that - so they're kind of in the PC ecosystem and kind of not.