If you want to be a great American, you have got to understand Ben Franklin, Thomas Jefferson, George Washington, how the American Revolution happened. I think if you want to be a good citizen of the digital age, it helps to feel comfortable with both the people and the ways of thinking that created the digital revolution.

Jobs insisted that Apple focus on just two or three priorities at a time. “There is no one better at turning off the noise that is going on around him,” Cook said. “That allows him to focus on a few things and say no to many things. Few people are really good at that.

Physics should represent a reality in time and space, free from spooky action at a distance.

Leonardo da Vinci had such a playful curiosity. If you read his notebooks, you'll see he's curious about what the tongue of a woodpecker looks like, but also why the sky is blue, or how an emotion forms on somebody's lips. He understood the beauty of everything. I've admired Leonardo my whole life, both as a kid who loved engineering - he was one of the coolest engineers in history - and then as a college student, when I travelled to see his notebooks and paintings.

Leonardo da Vinci was comfortable being illegitimate, gay, a misfit, a heretic. But he also respected other people. He didn't get into disputations. He was a genius but he had a certain humility. In his notebooks you see lists of people he wanted to grill about things like how the water diversions in Milan work; he was always interested in learning from other people.

People who know what they’re talking about don’t need PowerPoint.

Jobs has within him sort of this conflict, but he doesn't quite see it as a conflict between being hippie-ish and anti-materialistic but wanting to sell things like Wozniak's board. Wanting to create a business.