The Happiness Hypothesis: Putting Ancient Wisdom to the Test of Modern Science

by Jonathan Haidt

A person’s average or typical level of happiness is that person’s “affective style.” (“Affect” refers to the felt or experienced part of emotion.) Your affective style reflects the everyday balance of power between your approach system and your withdrawal system, and this balance can be read right from your forehead. It has long been known from studies of brainwaves that most people show an asymmetry: more activity either in the right frontal cortex or in the left frontal cortex. In the late 1980s, Richard Davidson at the University of Wisconsin discovered that these asymmetries correlated with a person’s general tendencies to experience positive and negative emotions. People showing more of a certain kind of brainwave coming through the left side of the forehead reported feeling more happiness in their daily lives and less fear, anxiety, and shame than people exhibiting higher activity on the right side. Later research showed that these cortical “lefties” are less subject to depression and recover more quickly from negative experiences.29 The difference between cortical righties and lefties can be seen even in infants: Ten-month-old babies showing more activity on the right side are more likely to cry when separated briefly from their mothers.30 And this difference in infancy appears to reflect an aspect of personality that is stable, for most people, all the way through adulthood.31 Babies who show a lot more activity on the right side of the forehead become toddlers who...