What would make you happier? Perhaps a bigger house or a better car; a sexier or more understanding mate; surely, wealth and fame. Or maybe you would simply be happy with finishing everything on your to-do list. Well, stop deluding yourself. Psychological research suggests that none of these things is very likely to increase your happiness significantly.

Take money, for example. Using data from the 2000 U.S. Census, David G. Myers documented an interesting discrepancy between wealth and happiness. Myers, a psychologist at Hope College in Holland, Mich., found that the buying power of the average American had tripled since 1950. So were Americans three times happier in 2000 than 50 years earlier?

The National Opinion Research Center at the University of Chicago has asked Americans to rate their level of happiness in surveys that have been conducted most years since 1957. When Myers compared these surveys with the economic data, he found that the proportion of Americans who describe themselves as "very happy" has remained remarkably stable at about one third. Despite being far better off financially than previous generations, we are no happier.

In fact, young Americans are more anxious than in the past. In 2000 Jean M. Twenge, a psychologist now at San Diego State University, published a sweeping analysis of 269 studies conducted between 1952 and 1993--all of which had measured the anxiety levels of children or college students. When Twenge correlated the measurements with the dates of the studies, she found a strong linear increase in reported anxiety over time. The average American child in the 1980s reported more anxiety than child psychiatric patients of the 1950s.

Psychologists have long studied anxiety and depression, but in recent years they have also begun exploring the nature of what makes humans happy. The field of "positive psychology" is now a burgeoning one, and its results have led to some surprising conclusions. There is a growing body of evidence that happiness is not something that can be achieved by hard work or good luck. The happiest people seem to be those who are fully engaged in the present, rather than focused on future goals. What can we do to increase the likelihood of being happy? The answers may lie in our biological past.

Thanks for the Inheritance
When evolutionary psychologists notice a universal aspect of how people perceive the world, they make an assumption: that slice of human nature must have been adaptive for our distant ancestors. During our long evolutionary history, we passed certain characteristics to the next generation when the individuals who possessed them were more likely to survive and have offspring. Other ways of reacting to the world were weeded out, because the individuals who possessed brains wired to respond in those ways were less likely to survive or have offspring.

What does natural selection have to do with happiness? We humans have inherited a remarkable capacity to habituate to, or become accustomed to, the status quo. Habituation is wonderfully adaptive when we are faced with adverse conditions, such as chronic noise or a permanent disability. After a while, we may no longer even notice these unpleasant circumstances. Unfortunately, habituation applies to positive aspects of our lives as well. No matter how pleasant an experience is at first, if it becomes a constant, we habituate to it.

We have also inherited a tendency to notice the negative more readily than the positive. Those early Homo sapiens who were most sensitive to negative changes in the environment were probably most likely to survive, because negative changes may have signaled danger. Like our distant relatives, we, too, have brains that are wired to notice trouble. So the natural human condition is to take positive experiences for granted and to focus on the bothersome aspects of life.

Last, one other aspect of human nature helps to prevent us from being satisfied: that little voice inside our head that often convinces us that our life would be better if only we possessed or accomplished something else. It is easy to see how early humans who were never quite satisfied would have had an advantage over their more easily satisfied peers. That nagging voice of dissatisfaction would have prompted our ancestors to strive for a bit more and then a bit more after that.

Today we all share a certain set of human characteristics that prime us to be on a perpetual search for a better life. But that does not explain why some people seem to be happier than others. We might assume that happy people are those who have finally achieved the good life. Psychologists, however, have learned that happiness is more closely tied to personality than to life experiences.

The Power of Personality
Personality differs from human nature in that it varies across individuals. At the same time, personality is relatively stable across each person's lifetime. Events come and go, but our traits and habitual ways of responding remain.

When it comes to happiness, events influence how we feel, at least in the short run. Winning the lottery is liable to prompt even the most cynical individual to experience a sudden spike in happiness. Still, people habituate to the way things are and fall back to their personal baseline level of happiness. It is this inherent baseline, or set point, of happiness that is an aspect of personality. So why do different people have different set points for happiness?

A study of twins published in 1996 points to the answer. Researchers Auke Tellegen and the late David Lykken of the University of Minnesota compared the similarity in happiness scores among sets of identical and fraternal twins who grew up together or were reared apart. These comparisons enabled the researchers to determine the degree to which variations in happiness are related to variations in our genes. They found that about 80 percent of the variation in happiness among individuals was attributable to genetic differences.

When most people hear the word "genetic," they tend to think "passed from parents to offspring." In this case, however, genetic refers to a characteristic arising from the novel way genes come together to form each unique individual. This fact explains why traits that have a strong genetic component may still vary widely between parents and their children or between siblings. Unless an individual has an identical twin, that person is truly one of a kind genetically.

The notion that each of us has an inherent baseline of happiness--largely determined by our genes--has important implications when combined with our shared human nature. The tendency to habituate to the status quo explains why, no matter what happens in our lives, we tend to return to our own individual set point of satisfaction with life.

Psychologists have discovered a number of personality traits that seem to be common in people with high set points of happiness. In a 1998 paper, social psychologist Kristina DeNeve of Baylor University (now at Creighton University) and psychologist Harris Cooper of the University of MissouriColumbia (now at Duke University) reviewed 148 studies of the relation between personality and happiness. Perhaps not surprisingly, they found that people who reported being happier also reported being more extroverted, friendly, trusting and conscientious. Happier people were also more likely to believe they had control over their lives and were less prone to anxiety and mood swings.

The personality traits associated with happiness seem to be characteristics that are also related to personal success and achievement. Can happiness (or at least satisfaction) be won through hard work and determination? After all, isn't that the core belief underlying the American dream?

Goals + Achievement = Happiness?
American capitalism rests on the assumption that we can achieve or buy happiness, a belief that fuels competition and consumerism. The research showing a lack of correlation between wealth and happiness casts doubt on this assumption. But competing for wealth is more than just an unproductive way to achieve happiness; it is a recipe for unhappiness.

Psychologists refer to our tendency to compare ourselves with those who are better off as "upward comparison," and it is known to engender dissatisfaction. Using data from U.S. surveys conducted by the National Opinion Research Center between 1989 and 1996, Michael R. Hagerty of the Graduate School of Management at the University of California, Davis, studied the relation between happiness and the distribution of wealth in one's community. He found that the greater the income disparity within a community, the less its residents were satisfied with their lives. Analyzing data from the U.S. and seven other nations collected between 1972 and 1994, Hagerty found that as the inequality of income lessened within a particular country, the average level of life satisfaction increased.

It seems that when we are aware that others are better off than we are, our own satisfaction suffers. Conversely, downward comparison (to those who are worse off than we are) tends to make us more appreciative and satisfied. The bad news? Upward comparison seems to come more naturally, a tendency that may be fueled by the mass media.

Even when we are not competing directly with others, our tendency to link happiness to the achievement of goals is counterproductive. Although more research is needed, psychologists William D. McIntosh of Georgia Southern University and Leonard L. Martin of the University of Georgia have theorized that people who repeatedly focus on attaining goals are less likely to be happy.

We might think of each person as falling somewhere along a continuum of linking happiness with goal attainment: from "nonlinker" to "strong linker." McIntosh and Martin say the problem with being a strong linker is the tendency to then be obsessively focused on meeting specific goals. Because of the belief that happiness depends on reaching those goals, strong linkers tend to experience anxiety and pressure as long as the goals remain unmet. They believe that happiness will be attained only at some future point. But what about when their goal is finally achieved?

After cherished goals are realized, habituation takes over, and strong linkers return to their previous baseline level of happiness just like everyone else. But when a strong linker realizes that his or her level of happiness has not permanently changed, the person typically concludes that happiness lies just over the next horizon.

Psychologists have found that we humans are good at deceiving ourselves about the future. We tend to believe that our prospects for increased happiness are better than our current circumstances. This tendency is nurtured by the media and advertising, which promise greater satisfaction with certain purchases or successes. People who persist as strong linkers tend to choose new goals, convinced that this time they have found the "real" path to happiness.

The choice to continue to link happiness to achievement of goals may be bolstered by observation. Doesn't it seem that successful people are happier? Research supports such a connection, but not in the way we usually assume.

In 2005 Sonja Lyubomirsky, a psychologist at the University of California, Riverside, and her colleagues reviewed the results of studies showing a positive correlation between happiness and success. They also examined longitudinal studies--in which happiness was measured both before and after some specific success--as well as experiments in which pleasant, neutral or negative feelings were induced in participants before the start of some task. In both types of research, happiness and positive mood were important as precursors to success. Happy people were not necessarily happier after their success than they were before, but they tended to be happier than others who were less successful.

Lyubomirsky concluded that success is related to happiness--but as a consequence, not a cause, of mood. The most likely explanation is that happy people have other personality traits that facilitate success. Also, a positive mood is liable to result in greater motivation, as well as cooperation from others. But how can you achieve happiness (and the success that comes with it) if your personality is not naturally sunny?

Go with the Flow
Mihaly Csikszentmihalyi, a psychologist at Claremont Graduate University, has concluded that the people who tend to be happier are those who report experiencing what he calls "flow." Csikszentmihalyi coined the term in a 1975 book that was based on hundreds of interviews. He has since published several other books on flow, which he defines as experiences that are inherently interesting and motivating for an individual because he or she becomes totally absorbed in them. That is not to say that flow experiences have to be fun (although frequently they are) but rather that flow involves being fully engaged. The task at hand is not too boring or too frustrating; it is sufficiently challenging to require one's full attention.

By incorporating the notion of flow, Western psychology has embraced the Eastern concept of mindfulness, which requires its practitioners to be nonjudgmental and conscious only of the present--immersed in what is happening right now. Unfortunately, this state of mind is not the norm for most of us; it is a skill that requires practice--through meditation, for example.

Why do people who report experiencing more flow also tend to be happier? Prominent psychologists, from Carl Rogers to Fritz Perls, describe psychological health as living in the present moment. Perhaps the link between happiness and flow has to do with the fact that flow experiences demand complete attention to the present. When we are totally engaged in what we are doing right now, it is impossible to focus on the past or future or to feel self-conscious--all of which tend to undermine satisfaction with life.

The growing body of research on happiness does not point to any easy answers. The roots of happiness are tangled, but understanding the inherent ways that our minds work does afford us the chance to make better choices about how we will invest our effort and time in the pursuit of happiness. Research from psychology seems to support what so many nonpsychologists have said before: happiness is not an ultimate destination but instead lies in appreciation of the journey.