a doctor may have the same economic incentives as a car salesman or a funeral director or a mutual fund manager: “If you’re an invasive cardiologist and Joe Smith, the local internist, is sending you patients, and if you tell them they don’t need the procedure, pretty soon Joe Smith doesn’t send patients anymore.” Armed with information, experts can exert a gigantic, if unspoken, leverage: fear. Fear that your children will find you dead on the bathroom floor of a heart attack if you do not have angioplasty surgery.
