His response: "Free software. Just kidding. Books actually."
His favorite book?
"My favorite of the last decade in Pinker's Better Angels of our Nature," says Gates. "It is long but profound look at the reduction in violence and discrimination over time."
Gates was also asked about the "cheapest thing that gives him pleasure since he became wealthy."
"Kids. Cheap cheeseburgers. Open Course Ware courses..." says Gates.
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