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From NPR News, this is ALL THINGS CONSIDERED. I'm Audie Cornish.
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And I'm Robert Siegel. The beginning of the New Year is a time when people take stock of their lives. They reflect on the past and contemplate the future. Well, be advised, a recent study found that people generally fail to recognize just how much their personality and values will change in the years ahead. NPR's Nell Greenfieldboyce reports that no matter how old you are, you seem to believe that you are who you are today is who you'll be tomorrow.
NELL GREENFIELDBOYCE, BYLINE: Daniel Gilbert is 55 years old. He says when he thinks about what he'll be like in the next decade, he has this feeling that he'll basically be the same person.
DANIEL GILBERT: I have this deep sense that although I will physically age, I'll have even less hair than I do and probably a few more pounds, that by and large, the core of me - my identity, my values, my personality, my deepest preferences - are not going to change from here on out.
GREENFIELDBOYCE: Gilbert is a psychologist at Harvard University. It occurred to him that this feeling was rather odd. He knows he's changed a lot in the past. He's a different person now than he was when he was younger.
GILBERT: Is it really the case that we all think that development is a process that's brought us to this particular moment in time, but now we're pretty much done?
GREENFIELDBOYCE: He and his colleagues wanted to investigate this idea, but first they had to figure out how. One thing they could do was just ask people how much do you think you'll change in the next decade, then wait around to see if people's predictions were right.
GILBERT: The problem with that is, it takes 10 years.
GREENFIELDBOYCE: So Gilbert says they came up with a much quicker approach. The researchers got almost 20,000 people to take some surveys. There were questions about their personality traits, their core values, and preferences. Some people were asked to look back on how they changed over the last 10 years. Others were asked to predict how they thought they would change in the next decade. Then the scientists crunched the data.
GILBERT: We're able to determine whether, for example, 40-year-olds looking backwards remember changing more than 30-year-olds looking forwards predict they will change.
GREENFIELDBOYCE: They found that people underestimated how much they will change in the future. People just didn't recognize how much their seemingly essential selves would shift and grow. And this was true whether they were in their teen years or middle-aged like Gilbert.
GILBERT: Life is a process of growing and changing, and what our results suggest is that growth and change really never stops, despite the fact that at every age from 18 to 68, we think it's pretty much come to a close.
GREENFIELDBOYCE: Now, Gilbert says personality changes do take place faster when people are younger.
GILBERT: A person who says I've changed more in the past decade than I expect to change in the future is not wrong. They are correct.
GREENFIELDBOYCE: But that doesn't mean they fully understand what's still to come.
GILBERT: Their estimates of how much they'll change in the future are under-estimates. They're going to change more than they realize. Change does slow, it just doesn't slow as much as we think it will.
GREENFIELDBOYCE: The studies are reported in the journal Science, and it impressed Nicholas Epley, a psychology researcher at the University of Chicago.
NICHOLAS EPLEY: And I think the finding that comes out of it is a really fundamentally interesting one, and in some ways, a really ironic one as well.
GREENFIELDBOYCE: He says everyone seemed to remember change in the past just fine.
EPLEY: What was bad, though, was what they predicted for the future.
GREENFIELDBOYCE: He says if you want to know what your next 10 years will be like, it's probably good to look at what your past 10 years were like, even though we seem to not want to do that. Nell Greenfieldboyce, NPR News.