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embarked on what were to become the most famous studies in social psychology, if not the discipline of psychology as a whole. In these studies, men who were members of the general public came to Yale University’s Department of Psychology to take part in what they thought was a scientific study of the effects of punishment on learning. More specifically, partici-pants played the role of “teacher ” in a study where a “learner” had to learn a list of word pairs and then perform a memory task in which he was given the first word from each pair and asked to identify the correct match from a list of four. If the learner gave an incorrect answer, the teacher had to give him an electric shock, and the strength of the shock increased every time an error was made. These were delivered by means of an impressive shock machine on which there was an array of 30 switches—starting at 15 volts (labeled “slight shock”) an