In 1938 Harvard University began following 268 male undergraduate students (including future President John Kennedy) and kicked off the longest-running longitudinal study of human development in history, The Grant Study.  The study’s goal was to determine as best as possible what factors contribute most strongly to human flourishing.

George Vaillant, who directed the study for more than three decades, published the study’s most recent findings in the his book Triumphs of Experience. Earlier work on the study include Adaptation to Life, 1977, and Aging Well, 2002. Triumphs of Experience has been widely reviewed, and with good reason.The book and the study are fascinating and informative.

Vaillant raises a number of factors such as the powerful correlation between the warmth of relationships and health and happiness in your later years as well as how significant men’s relationships with their mothers are in determining their well-being in life.  For example, Vaillant notes that Men who had “warm” childhood relationships with their mothers took home $87,000 more per year than men whose mothers were uncaring.  Men who had poor childhood relationships with their mothers were much more likely to develop dementia when old. Late in their professional lives, the men’s boyhood relationships with their mothers — but not their fathers — were associated with effectiveness at work.

Vaillant also notes that what separates those who viewed themselves as truly happy from those who did not was not in the events that made up their lives — it was in how they responded to those events. The key difference between the happy person and the unhappy one was that one viewed themselves as a victim to their circumstances, while the other sought ways to use their circumstances to their advantage. The degree to which happiness was attained was in the adaptations the participants employed to deal with and shape their reality.

In Vallant’s own words, the #1 most important finding from the Grant Study is this: “The seventy-five years and twenty million dollars expended on the Grant Study points to a straightforward five-word conclusion: Happiness is love.  Full stop.”