Kenya’s M-Pesa proves that when people are empowered, they will use digital tech to innovate on their own behalf.

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.

If I had a dollar for every time someone made fun of me in high school-oh wait, I do!

Like my friend Warren Buffett, I feel particularly lucky to do something every day that I love to do. He calls it "tap dancing to work."

Getting the word out that, yes vaccines are great, the safety data's very, very clear, including any of these specific concerns, that's very important to our foundation.

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

The government is there day in and day out, if you want all kids to have education, if you want to run courts, if you want to have an army, if you want to have roads, you've got to have the taxation system that funds everything that you expect.