They thus have a collective interest in preserving its fertility by limiting the number of cattle-owners use the land. All the owners benefit from the common grazing ground. They thus have a collective interest in preserving its fertility by limiting the number of cattle that graze on it. Yet, the benefits of the land and its fertility go to all the owners irrespective of the extent to which each of them contributes to maintaining it, so an individual owner benefits most if she puts many cattle on the land while the other restrict the numbers they put on it. Hence if each owner pursues her individual interests, the number of cattle on the land will increase quickly and the grazing lands will be depleted in away that harms every owner acts rationally, the result will be collectively irrational- a 'tragedy of the common'. The analysis of collective action problems draws on rational choice theory. Is is, in other words, less a set of empirical observations than a model based on the assumption that people act rationally in pursuit of their individual interests. Moreover, rational choice theory and so the serious analysis of collective action problem really only arose in the twentieth century