“Whatever the context, positive-sum games require exchange. They require voluntary action. Benefits to both sides. Negative-sum games are rare. They’re wars of attrition. Verdun. Or a labor strike. Both sides are losing. Each side hopes it’s losing less than the other. As soon as one side figures it’s losing too much, the negative-sum game is over. Negative-sum games are like heavy elements that live for a short time before decaying into something else.”