“If you look back, adults are thinking they’ve grown and improved and progressed over the 10 years,” Lachman said. “People would be disappointed to think one hasn’t experienced growth.”
Similarly, she said, young and middle-aged adults tend to overestimate how much they will change in the future; they think they will be more satisfied with life over the next decade when there is little actual change.
Gilbert said that there’s a simple reason his study may depart from previous work in the area. The tests his group used looked at fundamental personality traits such as introversion or anxiety, and specifically avoided questions such as whether people think they will make more money, be more fit, or be more successful.
The researchers looked at characteristics that people, including Gilbert himself, think are more fixed. “I’m a middle-aged man and when I sit around talking with other middle-aged people, we talk about how we are different than when we were young,” Gilbert said. “What we never do is imagine in the future that we will be smiling knowingly at our naivete.”