Contact chances are lessened by social separatism when the differences between individuals' identifications keep them moving along separate channels and through different networks. For example, a minor labor leader of the garment industry and a Department of Agriculture farm agent in Iowa would have few common groups and might even lack intermediaries. A merchant in Paris may know more merchants in London than he does workers who live a mile from his home. The structure of involvement . The inner structure of any grouping is also not atomized but is composed of people who can be ordered according to their involvement in the grouping.
Involvement can vary greatly.
One might ask, for example, how active a man is in his professional group, or in his political community. A recent study of the political activity of the American population asked a representative sample a series of questions about participation in their political role. That is, there is a progressively smaller group involved in political activity as one moves towards greater participation. This phenomenon, here illustrated by one study, is found in all groups for which information is available. As the operator examines every new grouping that comes to his attention, he can expect that the J-curve will fit the distribution of activity therein.