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One of the well-established findings in positive psychology is that many of the important determinants of happiness and life satisfaction are social. A recently-published study by James Fowler and Nicholas Christakis reinforces this finding by showing that happiness spreads through social networks. We are likely to be happy to the degree that our friends or spouses are happy, and we are likely to become happier as they become happier.
These particular results are important because they expand the scope of positive psychology, which often has quite an individualistic - some would say selfish - emphasis. That is, we are told to be happy because of what will follow in its wake for us as individuals: good feelings, success, and health. The study by Fowler and Christakis provides an additional rationale for individual happiness: It can leads to the happiness of others and presumably produce desirable consequences for them. Accordingly, the pursuit of happiness may be more than a selfish journey.
Although this study has received widespread publicity, its details are worth reviewing, because some of the accounts in the media have apparently glossed over important nuances. For example, one of the Deans of my university sent out an e-mail to faculty and staff urging us to be happy. He did not cite the study by Fowler and Christakis, but given the timing and content of his message, I believe that his well-intended exhortation was inspired by a media account of the study. He observed that happiness could spread throughout an office, so we should all "get happy" in order to benefit our colleagues and further the goals of the university. The problem is that the study did not show happiness contagion among those who work together. It occurred only among friends and spouses.
The study analyzed data gathered from thousands of individuals from 1983 through 2003 as part of the Framingham Heart Study. Information was available not only about target individuals but also their family members, close friends, neighbors, and fellow workers. Target individuals included both men and women from the United States. They were mostly middle-aged and on average had completed several years of college.
Happiness was measured with four reverse-scored items from a depression inventory. That is, although intended to measure symptoms of depression, these items were phrased in terms of its opposite: "I felt hopeful about the future," "I was happy," "I enjoyed life," and "I felt that I was just as good as other people." These items cohere and are a plausible measure of happiness. In the research Fowler and Christakis reported, happiness was operationally defined as rating each of these four items at the top ("most or all of the time").
The first question of interest was whether the happiness of our associates is linked to our own happiness (or vice versa). The answer is yes. A happy individual with whom one is socially connected increases the likelihood of one's own happiness by about 9%, whereas an unhappy individual with whom one is connected decreases the likelihood of one's own happiness by about 7%. So, happiness is a bit more potent than unhappiness. And if I understand the data correctly, the relationship between happy associates and one's own happiness is strictly linear: the more, the better. But the relationship between unhappy associates and one's own (un)happiness is not linear. One unhappy associate takes a toll, but additional unhappy associates do not.
The second question of interest was whether changes in someone's happiness in the social network led to subsequent changes in one's own happiness. A close look at the data in terms of the nature of the relationship and changes in happiness over time was needed. Again, the answer is yes, although with qualifications. Having a friend who lived nearby (within one mile) and became happy increased one's own subsequent happiness. The same result was found for a spouse with whom one shared a residence. Increasing happiness among friends at a greater distance did not lead to changes in one's own happiness, and neither did having colleagues at work who became happy..
The researchers acknowledged that their data do not speak to why these results occurred, although their findings are reliable and rather robust. Psychologists know that many emotional states are literally contagious. All that matters is mere proximity. In the present case of happiness, physical proximity may set the stage for the spread of happiness but is not sufficient. Otherwise the changing happiness or unhappiness of the people with whom we work would affect our own happiness. Perhaps we also need to like the person, and the unfortunate implication of this conjecture is that we may not really like the people with whom we work. Maybe we see them as competitors or akin to office furniture. If happiness is a virus, it is not spread by casual contact, no matter how frequent.
In my previous blog entry Happiness Outliers, I speculated about what I called happiness legacies: groups of people united by an emphasis on living a psychologically good life. The first place to look for these legacies is probably not at the workplace. Someone needs to tell my Dean, perhaps adding the advice that the university should go out of its way to hire our friends and spouses, at least those who are happy.
Reference
Fowler, J. H., & Christakis, N. A. (2008). Dynamic spread of happiness in a large social network: longitudinal analysis over 20 years in the Framingham Heart Study. BMJ, 337, a2338.
