You're never going to get the amount of CO2 emitted to go down unless you deal with the one magic metric, which is CO2 per kilowatt-hour.

You know capitalism is this wonderful thing that motivates people, it causes wonderful inventions to be done. But in this area of diseases of the world at large, it's really let us down.

I think there will be PCs at every price point.

50 years from now we won't need as much human labour to do what manual workers do, so we should be able to take that extra productivity and put it to better use.

If Africa seeks prosperity, it must provide for the health and nutrition of all – including the poorest.

Globalization has made copper and other minerals more valuable, and Ghana and Kenya have recently discovered mineral resources.

The spread of online information isn't just good for charities. It's also good for donors. You can go to a site like Charity Navigator, which evaluates nonprofits on their financial health as well as the amount of information they share about their work.