LOS ANGELES – Glancing around his study on a recent afternoon, Harvard psychologist Daniel Gilbert's eyes came to rest on his collection of thousands of music CDs, acquired over many years at considerable expense.
I don't listen to a lot of them anymore, he said. I was certain I'd listen to Miles Davis until the day I died.
According to his own research, Gilbert is hardly alone in having imagined that he'd always like the same music, or hobbies or friends.
Writing this month in the journal Science, he reported that people at all stages of life tend to believe they won't change much in the future – even as they recognize great shifts in their personalities, values and tastes in the past.
Calling it the end of history illusion, he and his colleagues suggested that the phenomenon might help explain why people make decisions they later regret: marrying the wrong person or buying an expensive vacation home.
We recognize it in teenagers, Gilbert said. We say to them, ‘You're not going to like that Megadeth tattoo in 10 years.' But no matter how old you are, you're making the same mistake.
Gilbert, who is 55, said he became interested in studying the end of history illusion based on his own experiences in middle age.
I've had this sense that I was finished baking – that I'd still be me, but older, he said.
He decided to test that intuition through a series of experiments.
An obvious approach would have been to have subjects make predictions about their future selves, wait 10 years, and see if they were right, Gilbert said. But lacking that kind of lead time, he and his colleagues devised a way to get the same information from a single moment in time.
Recruiting viewers of a popular French documentary hosted by study coauthor Jordi Quoidbach, a postdoctoral researcher in Gilbert's lab, the scientists assigned some to answer questions designed to arrive at core aspects of their identity and to predict how those responses might differ 10 years in the future. Among other things, subjects were asked to list their favorite foods or hobbies, rank values such as success and security, or answer a standard questionnaire designed to home in on personality traits like conscientiousness and emotional stability.
Other volunteers were asked to consider the same traits, but report how they had changed in the past decade.
Pairing up future-focused predictors and backward-looking reporters – such that the predictions of 25-year-olds were compared to the recollections of 35-year-olds, for instance – the researchers found that people consistently acknowledged they had changed a lot in the past but underestimated how much they would change in the future. The results held true for each decade of life between ages 18 and 68.
In all, more than 19,000 people recruited from Quoidbach's show took part in the experiment. Although the effect was stronger in younger people than in older people, it did not disappear, Gilbert said.
Was this merely an interesting quirk, or did it have consequences? To find out, the team conducted another experiment to gauge whether people's unwillingness or inability to recognize how much they'll change in the future leads them to pay too much for things today.
Recruiting another 170 subjects online, they asked some to name their favorite music group and say how much they'd pay to see the band in concert 10 years from now. They asked others to recall their favorite band from 10 years ago and say how much they'd pay to see them today.