“In an experiment at Stanford University known as the ‘marshmallow’ test,’ four-year-olds were brought into a room one by one. On the table in the room was a marshmallow. Each child was told, ‘You can have this marshmallow now if you want. But if you don’t eat it until after I get back from running an errand, you have two when I return.’ Fourteen years later, at the time these children were graduating from high school, researchers compared the children who ate the marshmallow immediately with the children who waited and got two. Those who grabbed the marshmallow were (as eighteen-year-olds) more likely to fall apart under stress, had a tendency to become irritated and to pick fights more often, and were less able to resist temptation in pursuit of their goals. There was also a completely unanticipated and surprising finding in this comparison of the young adults: the SAT scores of the children who had waited were an average of 210 points higher (out of a possible 1600 points) than the scores of those who had not waited” (Richard Winter, Still Bored in a Culture of Entertainment, p. 50).
The only question is why this was unanticipated . . .