The blond-headed boy is 4-years old and in pre-school. The adult tells him that the yummy delicious marshmallow in front of him is his to eat now or later. If he waits in the chair until she comes back to eat it, he’ll get rewarded with a second marshmallow. The young boy squirms in his chair, fights the urge to sink his teeth into the gooey sugary treat in front of him, and waits the interminable 10 minutes. The adult who is a child psychologist rewards him with the second marshmallow, and he immediately stuffs both marshmallows into his grinning mouth.