Emotions Help Solve the Prisoner’s Dilemma

Many philosophies treat emotions as the polar opposite of logic, and an economist would judge emotions as irrational. Taking an evolutionary perspective informs us that emotion is no less rational than any other behaviour, and likely evolved to maximize lifetime utility. Frank (1988) argues that emotions evolved to enable us to sacrifice a short-term benefit for a longer-term gain. Frank’s work is interpreted via a bottom-up evolutionary approach within the framework of the prisoner’s dilemma. Emotions help solve the prisoner’s dilemma by enabling us to cooperate. Emotions allow us to selectively lower our discount rate, and to be effective must be both visible and credible. Credible emotions are achieved by their manifestation in both the iterated prisoner’s dilemma (where they help us cooperate) and the non-repeated prisoner’s dilemma (where they