The Grant Study ... is now the longest longitudinal study of biosocial human development ever undertaken, and is still on-going. The studys goal was to identify the key factors to a happy and healthy life. In 2009, I delved into the Grant Study data to establish a Decathlon of Flourishing - a set of ten accomplishments that covered many different facets of success. Two of the items in the Decathlon had to do with economic success, four with mental and physical health, and four with social supports and relationships. Then I set out to see how these accomplishments correlated, or didnt, with three gifts of nature and nurture - physical constitution, social and economic advantage, and a loving childhood. The results were as clear-cut as they were startling. In contrast with the weak and scattershot correlations among the biological and socioeconomic variables, a loving childhood - and other factors like empathic capacity and warm relationships as a young adult - predicted later success in all ten categories of the Decathlon. Whats more, success in relationships was very highly correlated with both economic success and strong mental and physical health. In short, it was a history of warm intimate relationships ... that predicted flourishing. The Grant Study finds that nurture trumps nature. And by far the most important influence on a flourishing life is love. Not early love exclusively, and not necessarily romantic love. But love early in life facilitates not only love later on, but also the other trappings of success, such as high income and prestige.