In his book “The Youngest Science,” the great physician-writer Lewis Thomas described his internship at Boston City Hospital in pre-penicillin 1937. Hospital work, he observed, was mainly custodial. “If being in a hospital bed made a difference,” he said, “it was mostly the difference produced by warmth, shelter, and food, and attentive, friendly care, and the matchless skill of the nurses in providing these things. Whether you survived or not depended on the natural history of the disease itself. Medicine made little or no difference.”