The part of uranium that's fissile - when you hit it with a neutron, it splits in two - is about 0.7%. The reactors we have today are burning that 0.7%.

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.'

In order for the United States to do the right things for the long term, it appears to be helpful for us to have the prospect of humiliation. Sputnik helped us fund good science - really good science: the semiconductor came out of it.

Although I don't have a prescription for what others should do, I know I have been very fortunate and feel a responsibility to give back to society in a very significant way.

I've always been amazed by Da Vinci, because he worked out science on his own. He would work by drawing things and writing down his ideas. Of course, he designed all sorts of flying machines way before you could actually build something like that.

Antitrust is the way that the government promotes markets when there are market failures. It has nothing to do with the idea of free information.

How we deal with the AIDS epidemic should be one of the greatest ways that the world gets measured. The report card for this era.