Story of Psychology - Morton Hunt [279]
Since neither knows what the other is doing, each has to decide for himself what move might be best. But as in the original Prisoner’s Dilemma, logical reasoning doesn’t help; only if both players trust each other to do what is best for both will they choose X and A respectively, and each win $9. If either mistrusts the other or tries to do the best for himself without regard to the other’s welfare, he may win $10 while the other loses that much—but is equally likely to lose $10 while the other wins that much, or, along with the other player, lose $9.
Deutsch varied the conditions under which his student volunteers played so as to simulate and test the effects of a number of real-life circumstances. To induce cooperative motivation, he told some volunteers, “You should consider yourself to be partners. You’re interested in your partner’s welfare as well as your own.” To induce individualistic motivation, he told others, “Your only motivation should be to win as much as you can for yourself. You are to have no interest whatever in whether the other person wins or loses. This is not a competitive game.” Finally, to induce a competitive mind-set, he told still others, “Your motivation should be to win as much money as you can for yourself and also to do better than the other person. You want to make rather than lose money, but you also want to come out ahead of the other person.”
Usually, players made their choices simultaneously without knowing each other’s choice, but sometimes Deutsch had the first player choose and then transmit his choice to the second player, who would then make his choice. At other times, one or both players were allowed to change their choice when they heard what the other had chosen. And sometimes both were allowed to pass each other notes stating their intentions, such as, “I will cooperate, and I would like you to cooperate. That way we can both win.”49
As Deutsch had hypothesized, when the players were oriented to think of each other’s welfare, they behaved in a trusting fashion (they chose X and A)—and did the best, collectively, even though either one would have been the big loser if the other had double-crossed him. But when they were told to try to win the most and to best the other, each usually assumed that the other was also out to win at his expense and made choices that were good for only one and bad for the other, or bad for both.
An encouraging result, Deutsch has said, is that “mutual trust can occur even under circumstances in which the people involved are clearly unconcerned with each other’s welfare, provided that the characteristics of the situation are such that they lead one to expect one’s trust to be fulfilled.”50 That is the case when, for instance, one player is able to propose to the other a system of cooperation, with rules and penalties for infractions; or when one knows, before committing himself to a choice, what the other was going to do; or when one can influence the outcome for the other, with the result that it is not in the other’s interest to violate an agreement.
Deutsch’s use of the modified Prisoner’s Dilemma game was a seminal event in social psychology. It led to hundreds of similar studies by others who modified and varied the conditions of play in order to explore a range of other factors that encouraged either cooperative or competitive styles of conflict resolution.
Deutsch himself