Mischel’s story isn’t surprising—nicotine is addictive, and quitting is difficult—except for one thing: Mischel is the creator of the marshmallow test, one of the most famous experiments in the history of psychology, which is often cited as evidence of the importance of self-control. In the original test, which was administered at the Bing Nursery School, at Stanford, in the nineteen-sixties, Mischel’s team would 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 promised treats were always visible and the child knew that all she had to do to stop the agonizing wait was ring a bell to call the experimenter back—although in that case, she wouldn’t get the second treat. The longer a child delayed gratification, Mischel found—that is, the longer she was able to wait—the better she would fare later in life at numerous measures of what we now call executive function. She would perform better academically, earn more money, and be healthier and happier. She would also be more likely to avoid a number of negative outcomes, including jail time, obesity, and drug use.
