Marshmallow experiment

The marshmallow experiment is a famous test of the concept of deferred gratification by Walter Mischel, an American psychologist. In the 1960's he tested a group of four-year olds, by giving them a marshmallow and promising them more, if they could wait 20 minutes before eating the first one. Some children could wait and others could not. He then followed the progress of each child into adulthood, and demonstrated that those with the ability to wait were more successful in life than those who couldn't..