In October 2014, Ezekiel Emanuel published an essay in the Atlantic called “Why I Hope to Die at 75.” Because Emanuel is a medical doctor and chair of the University of Pennsylvania’s department of medical ethics and health policy, as well as a chief architect of Obamacare, the article stirred enormous controversy. Emanuel vowed to refuse not only heroic medical interventions once he turned 75, but also antibiotics and vaccinations. His argument: older Americans live too long in a diminished state, raising the question of, as he put it, “whether our consumption is worth our contribution.” Emanuel was born into...