In an age of terror, national leaders face this sort of question every day. Should we negotiate with the Taliban? Iran? North Korea? What about terrorist groups holding hostages? In private disputes, you may face devils of your own. A business partner has betrayed you and now wants to negotiate a better deal. Your marriage is ending and your spouse is making extortionist demands. A business competitor has stolen your intellectual property. Your sister is fighting you over an inheritance. In cases such as these, you feel outraged. Your gut tells you to fight it out in court.