the land, abrogating the commoners' rights. Although open-access resource systems may collapse due to overuse (such as in overfishing), many examples have existed and still do exist where members of a community with regulated access to a common resource co-operate to exploit those resources prudently without collapse, or even creating "perfect order". Elinor Ostrom was awarded the 2009 Nobel Memorial Prize in Economic Sciences for demonstrating this concept in her book Governing the Commons, which included examples of how local communities were able to do this without top-down regulations or privatization. On the other hand, Dieter Helm argues that these examples are context-specific and the tragedy of the commons "is not generally solved this way. If it were, the destruction of nature would not have occurred." In a modern global economic context, "commons" is taken to mean any open-access and unregulated resource such as the atmosphere, oceans, rivers, ocean fish stocks, or even an office refrigerator. In an Anglo-Saxon legal context the concept of the commons derive from a centuries old principle that not all land can be in private hands, but certain types of goods should only belong to the society. Here commons is a type of property that is neither private nor public, but rather held jointly by the members of a community in the interest of the community, who govern access and use through social structures, traditions, or formal rules. In environmental science, the "tragedy of the commons" is often cited in connection with sustainable development, meshing economic growth and environmental protection, as well as in the debate over global warming. It has also been used in analyzing behavior in the fields of economics, evolutionary psychology, anthropology, game theory, politics, taxation, and sociology. Expositions Lloyd's pamphlet In 1833, the English economist William Forster Lloyd published a pamphlet which included a hypothetical example of over-use of a common resource. This was the situation of cattle herders sharing a common parcel of land on which they were each entitled to let their cows graze, as was the custom in English villages. He postulated that if a herder put more than his allotted number of cattle on the common, overgrazing could result. For each additional animal, a herder could receive additional benefits, while the whole group shared the resulting damage to the commons. If all herders made this individually rational economic decision, the common could be depleted or even destroyed,