grantWhy do two men from very similar socioeconomic and educational backgrounds sometimes take very different life paths? Is nature or nurture more important in determining a man’s success in his relationships and career? What physiological and psychological traits present in a man’s younger years predict his chances of living a long, flourishing life? In 1938, researchers at Harvard’s medical school began a study that aimed to answer these fascinating questions and discover what factors lead to an “optimum” life. At The Art of Manliness