This dynamic was captured by what The Economist called, fifteen years ago, the “U-bend of life,” noting then that life was not “a long slow decline from sunlit uplands towards the valley of death.” Instead, a “reversal few expect” occurred at some point, according to an incredible process: “The shape of a lifespan, it turns out, is a paradox: happiness dips, then rises, defying both popular fear and youth’s assumptions.”