“The shortest path to oneself leads around the world.” So wrote German philosopher Count Hermann Keyserling, who believed that travel was the best way to discover who you are.

That was how 22-year-old Christopher McCandless was thinking in the summer of 1990, when he decided to leave everything behind—including his family, friends and career plans. He gave his bank balance of $24,000 to the charity Oxfam International and hitchhiked around the country, ending up in Alaska. There he survived for about four months in the wilderness before dying of starvation in August 1992. His life became the subject of writer Jon Krakauer’s 1996 book Into the Wild, which inspired the 2007 film of the same name.

Not every newly minted college graduate is as impulsive and restless as McCandless was, but studies conducted since the 1970s by personality researchers Paul Costa and Robert R. McCrae of the National Institutes of Health confirm that people tend to be open to new experiences during their teens and early 20s. Young people fantasize about becoming an adventurer like McCandless rather than following in the footsteps of a grandparent who spent decades working for the same company. But after a person’s early 20s, the fascination with novelty declines, and resistance to change increases. As Costa and McCrae found, this pattern holds true regardless of cultural background.

Although people typically lose their appetite for novelty as they age, many continue to claim a passion for it. Voters cheer on politicians who pledge change. Dieters flock to nutritional programs advertising a dream figure in only five weeks. Consumers embrace self-help books promising personal transformation. And scientists tell us that novel stimuli are good for our brains, promoting learning and memory [see “Learning by Surprise”].

Yet even as people older than 30 yearn for what is new, many find themselves unable or unwilling to make fundamental changes in their lives. Researchers say this paradox can be largely explained by the demands of adult responsibilities and that unrealistic expectations may also play a part in thwarting our best intentions. Change is rarely as easy as we think it will be.

The Age of Openness
Psychologists have long identified openness to new experiences as one of the “Big Five” personality traits, which also include extroversion, agreeableness, conscientiousness and neuroticism. Considerable disagreement exists about how much these personality traits change after age 30, but most research suggests that openness declines in adulthood.

“Clear age trends are observable,” says psychologist Peter Borkenau of Martin Luther University Halle-Wittenberg in Germany. “People tend to become more reliable and agreeable with age, but their openness to novelty drops at the same time.”

In a comprehensive survey of more than 130,000 participants published in 2003, psychologist Sanjay Srivastava, now at the University of Oregon, and his colleagues assessed the Big Five traits in 21- to 60-year-olds using standard psychological tests on the Internet. They found that openness increased modestly up to age 30 and then declined slowly in both men and women. The survey results suggest that men begin adulthood slightly more open to new experiences than women but decline in openness during their 30s at a faster rate than women.

Age 30 is not a magical turning point, however. Openness declines gradually over many years, often beginning in the 20s. As the years wear on, novelty becomes less and less stimulating, and the world outside someone’s own private and professional sanctums becomes increasingly less attractive.

This change happens to almost everyone, regardless of individual personality. That does not mean that everyone reaches the same level of openness in later life, however. Some toddlers love to go back to the same playground day after day, whereas others get bored after a day or two of digging in the same sandbox with the same shovel. Children who are less open to new experiences than their peers are will continue in adulthood to cleave to the conventional more than their more adventurous childhood friends will. As psychologist Richard W. Robins of the University of California, Davis, showed in a longitudinal study, those who begin life with a more open personality remain relatively more open in their later years.

Nature or Nurture?
The fact that an age-dependent pattern of decreasing openness appears around the globe and in all cultures suggests, according to biopsychologists, a genetic basis. But the jury is still out. As psychologist and personality researcher Rainer Riemann of Bielefeld University in Germany points out, it is conceivable that people all over the globe are simply confronted with similar life demands and societal expectations. Young men and women everywhere have to go out into the world and find a partner and a livelihood. Later, they have to care for their children and grandchildren. These life tasks require commitment and consistency and may serve as a catalyst for personality change.

Once a family and career are in place, novelty may no longer be as welcome. New experiences may bring innovation and awakening but also chaos and insecurity. And so most people dream of novelty but hold fast to the familiar. Over time we become creatures of habit: enjoying the same dishes when we eat out, vacationing in favorite spots and falling into daily routines [see “Foraging in the Modern World”].

“The brain is always trying to automate things and to create habits, which it imbues with feelings of pleasure. Holding to the tried and true gives us a feeling of security, safety, and competence while at the same time reducing our fear of the future and of failure,” writes brain researcher Gerhard Roth of the University of Bremen in Germany in his 2007 book whose title translates as Personality, Decision, and Behavior.

But even negative events may have thoroughly positive results, according to sociologist Deborah Carr of Rutgers University. For example, many widows are able to start life over again and to develop talents they never knew they had. People who have been diagnosed with cancer learn to redefine themselves as a result of the disease—and may even conquer their cancer in the process. Survivors of natural catastrophes often discover new strengths. But we should not draw sweeping conclusions from these examples, says psychologist William R. Miller of the University of New Mexico. Many older people report that they have changed little in spite of major life experiences.

In a recent experiment psychologist Kate C. McLean of the University of Toronto Mississauga asked 134 volunteers of different ages—some older than 65 and others ranging in age from late adolescence through young adulthood—to describe three self-defining memories. She found that both old and young participants reported novel experiences such as the death of a partner, an unexpected career advancement or a cross-country move. The older people ascribed different meanings to these events than the younger people did, however. For younger people, external changes were more likely to lead to internal transformation, but that was not the case for older individuals.

These very different narratives are no coincidence. Personality traits change more during young adulthood than any other period of life, according to psychologist Brent W. Roberts of the University of Illinois, who together with two colleagues analyzed 92 studies of personality development. They concluded that some personality changes occur well past the age of 30 but that typically these changes are small in magnitude compared with the changes that occur between the ages of 20 and 40.

Even major life events such as a divorce or the death of a loved one, though stressful, are unlikely to result in profound personality changes. The middle years of life are often a time of reflection and reevaluation, but few people experience a genuine “midlife crisis.”

The structure of one’s personality becomes increasingly stable until about age 60. “That means that a person who is particularly conscientious at the age of 40 will be conscientious at 60 as well,” Borkenau says. Stability decreases again, however, after the age of 60. It seems that people are only able to become more open to new experiences once they have fulfilled their life obligations—that is, after they have retired from their careers and their children have flown the nest.

False Hope Springs Eternal
Even after age 60 it is difficult to completely reframe your life. In fact, those who seek to make large changes often end up failing even to make the most minor corrections. The more an individual believes he can set his own rudder as he pleases, the more likely he is to run aground. That’s one reason why so many smokers who tell you that they can quit whenever they want are still smoking 20 years later.

In 1999 psychologists Janet Polivy and C. Peter Herman of the University of Toronto Mississauga coined a term for this phenomenon: false hope syndrome. Over and over, they say, people undertake both small and large changes in their lives. Most of these attempts never get anywhere, thanks to overblown expectations [see “Picture Imperfect,” by David Dunning, Chip Heath and Jerry M. Suls; Scientific American Mind, Vol. 16, No. 4, 2005].

Take the woman who believes that if she can lose 20 pounds she will finally meet the man of her dreams and live happily ever after. This fantasy is based on the notion that one positive change—losing weight—automatically brings with it other desired changes. But the reality is that it is difficult to keep weight off over the long term, and finding an ideal life partner is often dependent on luck. Even if dieting proves successful, other goals may remain out of reach. But the false hope syndrome seduces people into trying to overhaul their entire lives all at once: the smoker and couch potato is suddenly inspired to become a nonsmoker and marathon runner, but because he attempts too much too fast, he is doomed to fail.

The cure for false hope is to set more reasonable goals and recognize that achieving even modest change will be difficult. And if you are older than 30, remember that your openness to new experiences is slowly declining, so you are better off making a new start today than postponing it until later. Perhaps most important of all, try to appreciate the person that you already are.

As the ancient Greek philosopher Epicurus put it: “Do not spoil what you have by desiring what you have not; but remember that what you now have was once among the things only hoped for.”

Note: This article was originally published with the title, "Set In Our Ways".