Zimbardos psychologist textbook has athing run into dozen editions, 15 or 16 editions. The general outline of the experiment was, many years ago, walter michell did an experiment with four year old kids. He asked the child to come in and ask the child, then, do you want e atul? You can see this experiment, not walter michel's original experiment, but zimbardo's experiment. It's this very cute video that is available on youtube.