The marshmallow(棉花糖), a white, cottony, sweet confection (甜食)is synonymous(同义) with “temptation” in the US. This all began 50 years ago when psychologist Walter Mischel sat 5-year-old children down at a table and gave them a simple choice: they could eat one marshmallow now or, if they wait, receive two marshmallows later.

Mischel and his colleagues at Stanford wanted to understand the nature of self-control. If children could avoid eating the marshmallow over a set period of time, they were told they'd receive two as reward. If they couldn't resist temptation, they wouldn't get the second treat.

The Marshmallow Test became famous due to a remarkable discovery made some years later. Those children who were able to resist temptation for the reward of two marshmallows grew into adults who were more successful in school, work and relationships. They were also thinner, calmer, more sociable, better at managing their money, and less likely to be addicted to any substances.

It seems having the ability to wait for two marshmallows is quite important. In the US, there are “Don't Eat the Marshmallow!” T-shirts, and investment companies have used the marshmallow test to encourage retirement planning, according to The Atlantic.

Many people have interpreted the results of the Marshmallow Test to mean fate is predetermined by one's biology. But Mischel has just published a new book — The Marshmallow Test: Mastering Self-Control — which claims the true meaning of the experiments is just the opposite.

“The most important thing we learned is that self-control — the ability to regulate one's own emotions — involves a set of skills that can be taught, and learned,” Mischel told journalism website Vox.com. “They're acquirable. Nothing is predetermined.”

What's more, he says, these experiments provide concrete lessons about self-control we can use as adults. Grown-ups can use these methods to quit smoking, or stick to a diet, or save money.

Mischel and other psychologists argue that the battle between instant gratification (one marshmallow now) and long-term gratification (two marshmallows later) is really a battle between two different systems in the brain.