Which is better: a short, happy life, or a longer one with a not-so-happy ending? People's assessments of individual experiences--even an entire life's worth--appear to be based far more on quality, particularly at the end, than on the duration, psychologists report in the March issue of Psychological Science.
One of the more vivid examples of what psychologists call the "peak-end" theory comes from a study of people who underwent painful colonoscopy exams. They recall the experience as less unpleasant if there was only mild discomfort at the end, compared to a shorter exam that concluded with greater discomfort. This and other studies show that recollection of an event is shaped by its intensity and its end, but not so much by its duration.
To see whether this principle extends to judging an entire lifetime, a team of psychologists led by Ed Diener of the University of Illinois, Urbana-Champaign, composed various versions of the life of a fictional person named Jen. In one version, Jen lives a very happy, successful life, dying suddenly at 25. In another, she is happy till 25, then lives 5 more years that are somewhat less happy. The scenario is also reversed, with Jen being miserable or miserable with 5 extra moderately unhappy years. These patterns are also presented with Jen dropping dead in her 50s.
In a series of studies, the scientists found that both college-aged and middle-aged subjects tended to think that the short, happy life was preferable to the one with additional, moderately happy years. In the unhappy scenario, they preferred the sad life that brightened a little in the extra years. Both responses are "counterintuitive," Diener says, because they entail "rejecting the economic principle that people choose the most [cumulative] good." Instead, in both the happy and sad scenarios they chose the life with the highest average amount of happiness. He calls the preference for the short, happy life the "James Dean effect" after the wild young actor who died at 24.
Princeton psychologist Daniel Kahneman, who developed "peak-end" theory, explains that when people think of past events, they "tend to evaluate by the peak and by the end, and to be quite insensitive to how long it lasted."