This chapter deals with the mathematician Manfred Kochen, is one of Ithiel pool’s most farsighted and original contributions. It aims to develop a set of analytical tools to study the rise of contact networks, which establish new avenues for political influence and social change. Earlier in the twentieth century, it was more accurate to analyze politics as the study of groups. Social classes were more easily distinguished and there were moderate or strong correlations between social class and a wide range of attitudes and behavior. American politics typically involved the interaction of different organized groups: labor, business, and political parties. But the correlation of social class with other variables has diminished steadily in advanced industrial nations, and traditional political loyalties also have loosened. At least in these countries, more people have wider choices about their lives, are more widely traveled, relate more as individuals, have a wider circle of acquaintances, and the verb “to network” has become commonplace.