The single most important factor, he believes, is self-control. He describes the results of the Marshmallow Experiment in the six minute TED talk embedded below. In short, four-year-olds who were able to delay gratification enjoyed greater success as adults.
Jonah Lehrer also had an excellent write up on the Marshmallow Experiment in The New Yorker last week, from which I borrow these enlightening quotes:
At the time, psychologists assumed that children’s ability to wait depended on how badly they wanted the marshmallow. But it soon became obvious that every child craved the extra treat. What, then, determined self-control? Mischel’s conclusion, based on hundreds of hours of observation, was that the crucial skill was the “strategic allocation of attention.” Instead of getting obsessed with the marshmallow—the “hot stimulus”—the patient children distracted themselves by covering their eyes, pretending to play hide-and-seek underneath the desk, or singing songs from “Sesame Street.” Their desire wasn’t defeated—it was merely forgotten. “If you’re thinking about the marshmallow and how delicious it is, then you’re going to eat it,” Mischel says. “The key is to avoid thinking about it in the first place.”
[. . .]
When he and his colleagues taught children a simple set of mental tricks—such as pretending that the candy is only a picture, surrounded by an imaginary frame—he dramatically improved their self-control. The kids who hadn’t been able to wait sixty seconds could now wait fifteen minutes. “All I’ve done is given them some tips from their mental user manual,” Mischel says. “Once you realize that will power is just a matter of learning how to control your attention and thoughts, you can really begin to increase it.”
So distraction techniques can be useful for resisting temptation, but self-control involves more than just resisting temptation. Resisting bad things (temptations) is important, but it's arguably more important to resist neutral things. I don't think anyone needs to hide under the table to resist watching sports, for example, but it takes serious self-control for a person to put neutral things to the side in favor of better things.
Another limitation of this study as I see it is that they are being told not to eat the marshmallow, whereas outside of the lab we don't usually have the benefit of someone telling us not to eat too much junk food or whatever. Despite these limitations, the long term results of the study are amazing, and leave me with more questions than answers about the nature of self-control.
