There certainly is a case to be made that taxes should be more progressive.

In the next 15 years, we can halve childhood deaths. That's doable.

If you count E-mail, I'm on the Internet all day, every day.

In poor countries, we still need better ways to measure the effectiveness of the many government workers providing health services. They are the crucial link bringing tools such as vaccines and education to the people who need them most. How well trained are they? Are they showing up to work?

Today, we're very dependent on cheap energy. We just take it for granted - all the things you have in the house, the way industry works.

Teams should be able to act with the same unity of purpose and focus as a well motivated individual.

I realized about 10 years ago that my wealth has to go back to society. A fortune, the size of which is hard to imagine, is best not passed on to one's children. It's not constructive for them.