It sounds like the ending of a made-for-TV movie: On the operating table after a catastrophic medical event, a patient is suddenly thrust from their physical form and observes the scene from above, before being drawn to a dazzling white light. They pass by memories and loved ones as they move toward it, all the while overwhelmed by total joy and peace. But this isn’t fiction, and it isn’t an ending—the patient recovers against the odds and returns to ordinary, waking life where they recount what they perceive as a brush with heaven itself.

Thousands of people have reported near-death experiences (NDEs) since the 1970s when they were first studied seriously as a scientific and spiritual phenomenon. Experiencers, as they call themselves, reason that the consistency of their various ...