A recent study by psychologists at the University of Edinburgh tracking 973 pairs of twins shows that the heritable differences in self-reported happiness are entirely accounted for by the genes that determine the Big Five personality traits. That is to say, differences of personality account for all the heritable difference in happiness. In particular, low neuroticism and high extraversion are strongly correlated with higher levels of happiness, high conscientiousness is a bit less strongly correlated, and high agreeableness and openness to experience are positive but not so important. Non-neurotic, conscientious extraverts are the winners in the genetic happiness lottery.
This is important stuff. It tells us that individual variability matters. Individual-level strategies for improving happiness depend a great deal on the art of self-management given the constraints of personality. For example, I am very low in neuroticism and mildly extraverted, which bodes very well for my baseline level of happiness, but I am also extremely low in conscientiousness (not unlike a lot of homeless people and inmates), which ends up creating a lot of internal struggle and anxiety. For me, the key to higher levels of happiness is the conscious development of the habits of self-discipline and time management that don’t come naturally. The highly introverted or neurotic face challenges unique to their types. I look forward to future work that pushes deeper into happiness strategies for various combinations of personality traits.
And at a more general theoretical level, it is crucial to understand there are differences in the degree to which people revert to their baseline levels of happiness after good or bad changes in circumstances, and in difference in the rate of reversion. That will prevent us from making silly, sweeping generalizations about the insignificance of new cars or a lost limbs. When there is a lot of non-random variation, averages can lie. Regarding my previous post, I think it is important to recognize that not everyone compares themselves strongly to other people. Much of Robert Frank’s body of work is based, I think, on assuming a false uniformity in people’s disposition to compare themselves to others. We can avoid that kind of mistake if we attend more closely to the way individual happiness is mediated by personality.