Howard Thurman, the American author and philosopher, summarizes the same idea as follows: “Don’t just ask what the world needs. Ask what makes you come alive and go do it. What the world needs is people who have come alive.” Drew Houston, founder of Dropbox, agrees: “The most successful people are obsessed with solving an important problem, something that matters to them. They remind me of a dog chasing a tennis ball. To increase your own chances of happiness and success, you must find your tennis ball—the thing that pulls you.”