example he gave was of a rancher whose cattle stray onto the cropland of his neighbour. If the rancher is made to restrict his cattle, he is harmed just as the farmer is if the cattle remain unrestrained. Coase argued that without transaction costs the initial assignment of property rights makes no difference to whether or not the farmer and rancher can achieve the economically efficient outcome. If the cost of restraining cattle by, say, building a fence, is less than the cost of crop damage, the fence will be built. The initial assignment of property rights determines who builds the fence. If the farmer is responsible for the crop damage, the farmer will pay for the fence (as long the fence costs less than the crop damage). The allocation of property rights is primarily an equity issue, with consequences for the distribution of income and wealth, rather than an efficiency issue. With sufficient transaction costs, initial property rights matter for both equity and efficiency. From the point of view of economic efficiency, property rights should be assigned such that the owner of the rights wants to take the economically efficient action. To elaborate, if it is efficient not to restrict the cattle, the rancher should be given the rights (so that cattle can move about freely), whereas if it is efficient to restrict the cattle, the farmer should be given the rights over the movement of the cattle (so the cattle are restricted). This seminal argument forms the basis of the famous Coase theorem as labelled by Stigler. Law and economics Though trained as an economist, Coase spent much of his career working in a law school. He is a central figure in the development of the subfield of law and economics. He viewed law and economics as having two parts, the first "using the economists' approach and concepts to analyze the working of the legal system, often called the economic analysis of the law"; and the second "a study of the influence of the legal system on the working of the economic system." Coase said that the second part "is the part of law and economics in which I am most interested." In his Simons Lecture celebrating the centennial of the University of Chicago, titled "Law and Economics at Chicago", Coase noted that he only accidentally wandered into the field: Despite wandering accidentally into law and economics, the