The willingness to hear hard truth is vital not only for CEOs of big corporations but also for anyone who loves the truth. Sometimes the truth sounds like bad news, but it is just what we need.

Our modern lifestyle is not a political creation. Before 1700, everybody was poor as hell. Life was short and brutish. It wasn't because we didn't have good politicians; we had some really good politicians. But then we started inventing - electricity, steam engines, microprocessors, understanding genetics and medicine and things like that. Yes, stability and education are important - I'm not taking anything away from that - but innovation is the real driver of progress.

Cutting through complexity to find a solution runs through four predictable stages: determine a goal, find the highest-leverage approach, discover the ideal technology for that approach, and in the meantime, make the smartest application of the technology that you already have - whether it's something sophisticated, like a drug, or something simpler, like a bednet.

Well, no one gives aid to Zimbabwe through the Mugabe government.

More and more software would just increase the number of tasks that the computer would help solve.

At Microsoft there are lots of brilliant ideas but the image is that they all come from the top - I'm afraid that's not quite right.

The US in some ways has been the best. Who figured out shale gas? Although that wasn't a good thing [for CO2 levels], it was very innovative. It's led to low-cost energy. Who figured out nuclear power? Largely the United States. Once you get past the steam engine, which is mostly British, then the US has been at the center of most of the energy things that have happened.