The experiment went like this: Mischel invited a four-year old student at the Bing Nursery School into a small room, barely bigger than a closet. He then made her an offer. She could either eat one marshmallow right away or, if she was willing to wait fifteen minutes while he ran an errand, she could eat two marshmallows. Needless to say, most kids decided to wait.
Mischel then left the room, but told the child that if she rang the bell on the table he would come running back and she could eat the marshmallow. However, this meant forfeiting the chance to get a second marshmallow.
The vast majority of four-year-olds struggled to resist the allure of the marshmallow. (The average waiting time was less than two minutes.) “A few kids ate the marshmallow right away,” Mischel told me, when I wrote about his research in the New Yorker in 2009. “They didn’t even bother ringing the bell. Other kids would stare directly at the marshmallow and then ring the bell 30 seconds later.”
Fast forward twelve years: the preschoolers are now in high-school. Mischel sent out an extensive questionnaire to the parents, teachers and academic advisors of the nearly 600 subjects who participated in the marshmallow task. The multiple-choice survey had no single theme. Instead, Mischel asked about every trait he could think of, from the ability of the teenagers to control their temper to whether or not they “embraced challenges” and got along with their peers. He also requested a copy of their SAT scores.