“You’re the eighth rheumatologist that I’ve seen,” the patient told me. She ticked off her symptoms—pain, fatigue, and what she described as a sense of brain fog—which she’d lived with for years. Some doctors had no answers for her; others had said that she likely had fibromyalgia, a poorly understood pain-processing condition, and that they could do little to help. She began to cry, and I began to sweat. My medical training had prepared me for seemingly everything—diagnosing heart attacks, treating life-threatening infections—but not for this kind of problem. I knew the technical definition of fibromyalgia, but my confidence in making the diagnosis correctly was exceedingly low: The disease can cause the symptoms my patient described but cannot be proven by lab or imaging studies. And even if fibromyalgia was the cause of her suffering, I had few concrete solutions to offer her. Modern medicine is excellent at delivering treatments that precisely target the biological cause of a disease and produce clear, measurable improvement. The promise of such magic bullets shapes both doctors’ training and …