Dr. Jim Tucker at the University of Virginia had learned through years of studying reincarnation accounts to accept that reincarnation exists—but the strong indications that birthmarks correspond to past-life wounds still puzzled him. “I didn’t see how a wound on one body could show up as a birthmark on another, even if you accepted the idea of past-life connections,” he wrote in his book “Return to Life: Extraordinary Cases of Children Who Remember Past Lives.” His mentor and predecessor in reincarnation studies, Dr. Ian Stevenson, had verified many cases.