I love this bit from Michael Lewis’ profile of Obama in Vanity Fair in which Obama gives Lewis some practical advice for a hypothetical situation that in 30 minutes they would switch roles and Lewis would become president of the United States:

You also need to remove from your life the day-to-day problems that absorb most people for meaningful parts of their day. “You’ll see I wear only gray or blue suits,” [Obama] said. “I’m trying to pare down decisions. I don’t want to make decisions about what I’m eating or wearing. Because I have too many other decisions to make.” He mentioned research that shows the simple act of making decisions degrades one’s ability to make further decisions. It’s why shopping is so exhausting. “You need to focus your decision-making energy. You need to routinize yourself. You can’t be going through the day distracted by trivia.” The self-discipline he believes is required to do the job well comes at a high price. “You can’t wander around,” he said. “It’s much harder to be surprised. You don’t have those moments of serendipity. You don’t bump into a friend in a restaurant you haven’t seen in years. The loss of anonymity and the loss of surprise is an unnatural state. You adapt to it, but you don’t get used to it—at least I don’t.”

President Obama on Simplifying