We should all grow our own food and do our own waste processing, we really should.

I hope someday what people can do with their lives depends on their talents and how hard they are willing to work, rather than on where they happen to be born.

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?

I have been struck again and again by how important measurement is to improving the human condition.

I think the positive competition between states in India is one of the most positive dynamics that the country has.

So not only are we saving lives now, we're creating the incentive for the breakthroughs that over the next generation will mean we can take AIDS, malaria and TB and bring those numbers dramatically down.

Harnessing steam power required many innovations, as William Rosen chronicles in the book 'The Most Powerful Idea in the World.'