Can you train your brain to outsmart your shortcomings? Walter Mischel smoked three packs a day. While he knew his habit could kill him, he couldn't stop. This story isn't unusual. What is unusual is that Mischel is the psychologist behind the now famous marshmallow study - "present a child with a treat (marshmallows were just one option) and tell her that she could either eat the one treat immediately or wait alone in the room for several minutes until the researcher returned, at which point she could have two treats." The longer a child delayed gratification, the better she fared in life. She had higher grades, made more money, was healthier, and was happier. Despite proving the importance of self-control, Mischel couldn't stop smoking. And then one day, he quit. How? Mischel discovered what the self-controlled kids in his study discovered, he learned how to mentally "cool" cigarettes, the "hot" aspect of his environment. In other words, he trained his brain to have self-control. At 84 years old, Mischel, has just published his first popular book, The Marshmallow Test: Mastering Self-Control.