Lessons from the Marshmallow Experiment


By Joe Kearns

What could a marshmallow possibly suggest about a child’s future? Quite a lot, actually. Psychologist Walter Mischel’s Stanford marshmallow experiment and follow-up experiments demonstrated that the ability to delay gratification at a young age is positively correlated with success in a variety of educational, health, and other measures. This correlation has substantial implications for economists who attempt to understand irrational decision-making.

Mischel conducted his experiment at the Bing Nursery School at Stanford University in 1972, where boys and girls ranging from 3 to 5 years old were the subjects. Experimenters instructed the children to sit a table for 15 minutes with a marshmallow in front of them and promised them a second marshmallow if they did not eat the first. When experimenters followed up with the children many years later, the children who had delayed gratification and waited for the second marshmallow generally had higher SAT scores, lower levels of substance abuse, and a lower, healthier body mass index. The implication of this experiment is that the cognitive ability to delay gratification helps individuals accomplish life goals.

A new experiment incorporated an additional variable: the child’s perception of adults as reliable. The experiment conducted by University of Rochester researchers conditioned children to trust or distrust them by promising them a new box of art supplies prior to the marshmallow portion of the experiment and they either followed through on the promise or reneged on it. Only one of the children interacting with an “unreliable” adult waited the full fifteen minutes, while nine who interacted with a “reliable” one waited that time. This suggests that the social interaction of children with adults who influence them, particularly parents or teachers, conditions them to decide whether or not delayed gratification is worthwhile. Mischel refutes the notion that self-control is genetically deterministic, arguing that “the genome can be as malleable as we once believed only environments could be.”

These experiments together shed light on how individuals make decisions which seem irrational. This is particularly valuable for economists who examine how the average American with a credit card has almost $16,000 in debt or why the majority of American retirees turn down annuity payments in favor of a lump-sum payment that could run out in their life-times. There are countless economic decisions all individuals face when the temptation to eat the marshmallow exists. The ability to resist is sheer rationality, but it is not the whole of what it means to be human.