The Stanford marshmallow experiment was a series of studies on delayed gratification in the late 1960's and early 1970's led by psychologist Walter Mischel. Using children of ages four to six as subjects, they were led into a room where a treat (usually a marshmallow, but sometimes a cookie or pretzel stick), was placed on a table, by a chair. The children could eat the treat, the researchers said, but if they waited for fifteen minutes without giving in to the temptation, they would be…