The Marshmallow Test: Understanding Self-control and How To Master It

by Walter Mischel

Shakespeare’s Hamlet personified tragically unconstructive ways to appraise experience, he made this point insightfully: “There is nothing either good or bad, but thinking makes it so.”14 As Hamlet also showed, trying to change how we think about or “mentally represent” stimuli and experiences that have become deeply ingrained can be as futile as trying to be your own brain surgeon.

Perhaps those who came from homes with absent fathers — a common occurrence at that time in the African families in Trinidad, while very rare for the East Indians — had fewer experiences with men who kept their promises. If so, they would have less trust that the stranger — me — would ever really show up later with the promised delayed reward. There’s no good reason for anyone to forgo the “now” unless there is trust that the “later” will materialize.

Those who had consistently chosen to wait for larger but delayed rewards rather than immediate but smaller rewards in the earlier session cheated much less than those who had taken the smaller rewards.5 If the boys who had preferred the delayed rewards did cheat, they waited much longer before they gave in to the temptation to falsely inflate the scores they reported.

James Watson summarizes the conclusion: “A predisposition does not a predetermination make.”20

If you want to decide how something (a new job, an exotic trip) will feel in the future, you might try to imagine yourself doing it in the present.4 Simulate the events as vividly as possible, in great detail, by essentially pre-living them. When

“You are afraid of the dentist and have to get some dental work done.” During the procedure would you want him to tell you what he is doing or prefer to do mental puzzles in your head? People who want to know more are categorized as “monitors”; those who would rather not know and prefer to self-distract or suppress are “blunters.”16 Women who

a general rule for most people, if there is nothing you can do to reduce the stress because the situation is out of your control, monitoring typically increases anxiety and stress, and blunting tends to be more adaptive and self-protective.17

the diagnoses that highly competent physicians made while their patients were still alive in the hospital’s intensive care unit were compared with what their autopsies later revealed. Physicians who had been “completely certain” of their diagnosis turned out to be wrong 40 percent of the time.22 Early in my career, I lost many friends in

one task, for example, after spending five minutes crossing out every “e” in a typewritten text, students then had to not cross out an “e” if it was followed by a vowel. And when people are given strong incentives to persist even on tasks like that, they do continue longer. As motivation to exert self-control increases, effort continues.5 With no increase in motivation, it does not. In this interpretation, the reduction in self-control is not due to a loss of resources: it reflects, instead, changes in motivation and attention.

At Stanford University, Carol Dweck and her colleagues found that those who believed that their stamina fueled itself after tough mental exertion did not show diminished self-control after a depleting experience. In contrast, those who believed that their energy was depleted after a strenuous experience did show diminished self-control and had to rest to refuel.7

This is how Laibson explains his procrastination: He can exercise today (his effort cost is –6) to gain delayed health benefits (for him a future value of +8). The net benefit of exercising today for someone with his present bias is (–6 + ½ [8] = –2). In this equation, the future value of +8 was halved because of the automatic discounting of the future, making –2 the net benefit of his exercising today. In contrast, exercising tomorrow has a delayed effort cost of –6 and a delayed benefit of +8, both of which are halved because they are in the future (½ [–6 + 8] = +1). For Laibson the resulting net value for putting off going to the gym is +1, which is better than the –2 net value for exercising today. Consequently, he is rarely at the gym.

Why tomorrow never comes to the gym.

inflation in self-evaluation L. B. Alloy and L. Y. Abramson, “Judgment of Contingency in Depressed and Nondepressed Students: Sadder but Wiser?,” Journal of Experimental Psychology: General 108, no. 4 (1979): 441–485.