As you try to imagine yourself cruising along in the self-driving car of the future, you may think first of the technical challenges: how an automated vehicle could deal with construction, bad weather or a deer in the headlights. But the more difficult challenges may have to do with ethics. Should your car swerve to save the life of the child who just chased his ball into the street at the risk of killing the elderly couple driving the other way? Should this calculus be different when it’s your own life that’s at risk or the lives of your loved ones?