A New York nature study society operates a camp in upstate New York. A truckload of campers goes on a nature study trip to Massachusetts. There, the truck driver's negligence seriously injures a camper. Under New York law, the camper may recover damages from the society; under Massachusetts law, the society is immune from liability. But which law is to apply? Legal scholars in twelfth-century Italian city states grappled with choice-of-law decisions,...