Before giving an account of the experimental results, it is instructive to consider how persons predict others will perform when commanded to administer powerful shocks to another person. Fourteen Yale seniors, all psychology majors, were provided with a detailed description of the experimental situation. They were asked to reflect carefully on it, and to predict the behavior of 100 hypothetical subjects. More specifically, they were instructed to plot the distribution of obedience of "100 Americans of diverse occupations, and ranging in age from 20 to SO years," who were placed in the experimental situation. There was considerable agreement among the respondents on the expected behavior of hypothetical subjects. All respondents predicted that only an insignificant minority would go through to the end of the shock series. (The estimates ranged from 0 to 3%; i.e., the most "pessimistic" member of the class predicted that of 100 persons, 3 would continue through to the most potent shock available on the shock generator—450 volts.) The class mean was 1.2%. The question was also posed informally to colleagues of the author, and the most general feeling was that few if any subjects would go beyond the designation Very Strong Shock.
Result of Experiment I
Subjects accept situation. With few exceptions subjects were convinced of the reality of the experimental situation, that they were administering shocks to another person, and the most potent shocks were extremely painful. In the post-experimental interview subjects were asked: "How painful to the learner were the last few shocks that you administered to him?" Subjects were instructed to indicate their answers on a printed 14-point scale ranging from "Not at all painful" to "Extremely painful." The modal response was 14 (Extremely painful) with the mean at 13.42. Signs of extreme tension. Many subjects showed signs of nervousness in the experimental situation, and especially upon administering the more powerful shocks. In a large number of cases the degree of tension reached extremes that are rarely seen in sociopsychological laboratory studies. Subjects were observed to sweat, tremble, stutter, bite their lips, groan, and dig their fingernails into their flesh. These were characteristic rather than exceptional responses to the experiment. One sign of tension was the regular occurrence of nervous laughing fits. Fourteen of the 40 subjects showed definite signs of nervous laughter and smiling. The laughter seemed entirely out of place, even bizarre. Full-blown, uncontrollable seizures were observed for 3 subjects. On one occasion we observed a seizure so violently convulsive that it was necessary to call a halt to the experiment. The subject, a 46-year-old encyclopedia salesman, was seriously embarrassed by his untoward and uncontrollable behavior. In the post-experimental interviews subjects took pains to point out that they were not sadistic types, and that the laughter did not mean they enjoyed shocking the victim. Distribution of scores. It had been conjectured that persons would not, in general, agree to administer shocks beyond the level designated as Very Strong Shock. The distribution of maximum shocks for this experiment is shown in Table 2. The obtained distribution of scores deviates radically from the prediction. Upon command of the experimenter, each of the 40 subjects went beyond the expected breakoff point. No subject stopped prior to administering Shock Level 20. (At this level —300 volts—the victim kicks on the wall and no longer provides answers to the teacher's multiple-choice questions.) Of the 40 subjects, 5 refused to obey the experimental commands beyond the 300-voIt level. Four more subjects administered one further shock, and then refused to go on. Two broke off at the 330-volt level, and 1 each at 345, 360, and 375 volts. Thus a total of 14 subjects defied the experimenter. It is instructive to reprint their remarks at the point of defiance, as transcribed from the tape recordings:  I think he's trying to communicate, he's knocking. . . . Well it's not fair to shock the guy . . . these are terrific volts. I don't think this is very humane. . . . Oh, I can't go on with this; no, this isn't right. It's a hell of an experiment. The guy is suffering in there. No, I don't want to go on. This is crazy. [Subject refused to administer more shocks.]  He's banging in there. I'm gonna chicken out. I'd like to continue, but I can't do that to a man. . . . I'm sorry I can't do that to a man. I'll hurt his heart. You take your check. .. . No really, I couldn't do it. These subjects were frequently in a highly agitated and even angered state. Sometimes, verbal protest was at a minimum, and the subject simply got up from his chair in front of the shock generator, and indicated that he wished to leave the laboratory.