Extroversion & Happiness
A century ago, William James published a thin volume titled On Vital Reserves, The Energies of Men: The Gospel of Relaxation. It was more accessible to the lay public than his two-volume Principles of Psychology, and a flirtation perhaps with that genre known today as "self-help." His chief insight was that our volitional nature doesn't passively follow our moods and feelings, as is widely thought. "Action seems to follow feeling," he wrote, "but really action and feeling go together; and by regulating the action, which is under the more direct control of the will, we can indirectly regulate the feeling, which is not."
A study headed by William Fleeson, associate professor of psychology at Wake Forest University, in 2002 not only supports James' thesis but goes a step further: it suggests a link between acting extroverted and being happy. College students were asked to act cheerful and outgoing and assertive for a two-week period, and to describe their moods as they went along. Many of the students literally had to pretend to be in a good mood, to enjoy the company of others, to be upbeat, almost as if they were acting in a film. They were also asked during intervals to act withdrawn and shy and to evaluate the mood of their peers. According to Fleeson, every student reported being "happier" when acting extroverted and less so when acting introverted, and everyone thought the experiment was rewarding and entertaining.
His research suggests that no external condition (apart from obvious basic needs) is necessary to enhance the "happy state" -- the opposite of the view, perhaps widespread, that happiness is contingent upon having money and things, fame and social standing, or even the approbation of other people.
Dr. Fleeson's study, titled "An Intraindividual Process Approach to the Relationship Between Extraversion and Positive Affect: Is Acting Extraverted as 'Good' as Being Extraverted?," was published in the December 2002 issue of the Journal of Personality and Social Psychology.