A most significant consequence of the growing division of labour in modern society has been man's multiple participation in the social world. In traditional societies, the person's various group affiliations are interrelated in a sort of concentric pattern, so that membership in any social group or network necessarily implies membership in some others. In modern society, on the other hand, these affiliations may be represented by a web of intersecting circles which are not contained in — and are, at least in part, independent of — one another (Simmel, 1964).