In the late nineteen-sixties, Carolyn Weisz, a four-year-old with long brown hair, was invited into a “game room” at the Bing Nursery School, on the campus of Stanford University. The room was little more than a large closet, containing a desk and a chair. Carolyn was asked to sit down in the chair and pick a treat from a tray of marshmallows, cookies, and pretzel sticks. Carolyn chose the marshmallow. Although she’s now forty-four, Carolyn still has a weakness for those air-puffed balls of corn syrup and gelatine. “I know I shouldn’t like them,” she says. “But they’re just so delicious!” A researcher then made Carolyn an offer: she could either eat one marshmallow right away or, if she was willing to wait while he stepped out for a few minutes, she could have two marshmallows when he returned. He said that if she rang a bell on the desk while he was away he would come running back, and she could eat one marshmallow but would forfeit the second. Then he left the room.
Although Carolyn has no direct memory of the experiment, and the scientists would not release any information about the subjects, she strongly suspects that she was able to delay gratification. “I’ve always been really good at waiting,” Carolyn told me. “If you give me a challenge or a task, then I’m going to find a way to do it, even if it means not eating my favorite food.” Her mother, Karen Sortino, is still more certain: “Even as a young kid, Carolyn was very patient. I’m sure she would have waited.” But her brother Craig, who also took part in the experiment, displayed less fortitude. Craig, a year older than Carolyn, still remembers the torment of trying to wait. “At a certain point, it must have occurred to me that I was all by myself,” he recalls. “And so I just started taking all the candy.” According to Craig, he was also tested with little plastic toys—he could have a second one if he held out—and he broke into the desk, where he figured there would be additional toys. “I took everything I could,” he says. “I cleaned them out. After that, I noticed the teachers encouraged me to not go into the experiment room anymore.”
Footage of these experiments, which were conducted over several years, is poignant, as the kids struggle to delay gratification for just a little bit longer. Some cover their eyes with their hands or turn around so that they can’t see the tray. Others start kicking the desk, or tug on their pigtails, or stroke the marshmallow as if it were a tiny stuffed animal. One child, a boy with neatly parted hair, looks carefully around the room to make sure that nobody can see him. Then he picks up an Oreo, delicately twists it apart, and licks off the white cream filling before returning the cookie to the tray, a satisfied look on his face.
Most of the children were like Craig. They struggled to resist the treat and held out for an average of less than three minutes. “A few kids ate the marshmallow right away,” Walter Mischel, the Stanford professor of psychology in charge of the experiment, remembers. “They didn’t even bother ringing the bell. Other kids would stare directly at the marshmallow and then ring the bell thirty seconds later.” About thirty per cent of the children, however, were like Carolyn. They successfully delayed gratification until the researcher returned, some fifteen minutes later. These kids wrestled with temptation but found a way to resist.
The initial goal of the experiment was to identify the mental processes that allowed some people to delay gratification while others simply surrendered. After publishing a few papers on the Bing studies in the early seventies, Mischel moved on to other areas of personality research. “There are only so many things you can do with kids trying not to eat marshmallows.”
But occasionally Mischel would ask his three daughters, all of whom attended the Bing, about their friends from nursery school. “It was really just idle dinnertime conversation,” he says. “I’d ask them, ‘How’s Jane? How’s Eric? How are they doing in school?’ ” Mischel began to notice a link between the children’s academic performance as teen-agers and their ability to wait for the second marshmallow. He asked his daughters to assess their friends academically on a scale of zero to five. Comparing these ratings with the original data set, he saw a correlation. “That’s when I realized I had to do this seriously,” he says. Starting in 1981, Mischel sent out a questionnaire to all the reachable parents, teachers, and academic advisers of the six hundred and fifty-three subjects who had participated in the marshmallow task, who were by then in high school. He asked about every trait he could think of, from their capacity to plan and think ahead to their ability to “cope well with problems” and get along with their peers. He also requested their S.A.T. scores.
Once Mischel began analyzing the results, he noticed that low delayers, the children who rang the bell quickly, seemed more likely to have behavioral problems, both in school and at home. They got lower S.A.T. scores. They struggled in stressful situations, often had trouble paying attention, and found it difficult to maintain friendships. The child who could wait fifteen minutes had an S.A.T. score that was, on average, two hundred and ten points higher than that of the kid who could wait only thirty seconds.