German sociologist Ferdinand Tönnies first investigated the difference between 'community' and 'society' (respectively, Gemeinschaft and Gesellschaft). Small groups can exist in a sense of organic community, not requiring formal rules because a sense of common mores or norms unite them. Personal relationships can be cultivated and are quite strong, and there is little need for external enforcement. John Allen's quaint description of early Usenet illustrates Tönnies' idea of community. Larger groups find community hard to sustain. Individual interest rules behavior rather than common mores. Society, as opposed to community, is based on explicit rules that require enforcement. Society possesses greater flexibility and potentially more capability, but individuals are subject to greater anomie and anti-social behavior. Internal factional conflicts occur more frequently, despite the greater modularity of individuals' function in society.