Steve Lawton, after careening headlong into a tree at 45 miles per hour and suffering a major brain injury, believes every interaction with another person is a bonus that might never have happened. He credits his positive attitude with literally saving his life. He is the author of “Head First! A Crash Course in Positivity,” and is his role at Dell, he helps co-workers learn to harness their own power of intention and positive thinking to change the direction of their lives.