How do we turn the spectrum of social status into a ladder with rungs? This is a problem for sociology. Objectively, it seems that all the thousands of status distinctions add up to a smooth spectrum of individuals, not a structure of status groups. Yet we know that people make and experience social life as full of groups with boundaries that define who is in, and who is out.
One of the ways that we make these boundaries is by using educational credentials. Randall Collins, as I have noted in the last couple of posts, says that we are in an advanced state of a "credential society," where we use educational credentials, certifications, licenses, and so forth to make social distinctions that go way beyond the knowledge that those credentials can really certify.
Frank Parkin, a Weberian sociologist, wrote a wonderful book, Marxism and Class Structure: A Bourgeois Critique. He develops Weber's idea that social life has an endless process of creating and resisting social closure. The up group finds some marker to insist on that excludes the group below; the group below resists this usurpation of their upward claims -- and in turn exclude groups below them.
Class theorists rarely really grapple with how marriage relates to class and status structure. In the old days, a man's status was simply assumed to define the status of the women in his family. Since the '70s, we have been more careful to treat women's status separately from men's. Still, sociologists remain remarkably individualistic on this point. We do not have a theory of the social status of a married couple and their children.
Closure theory may be the beginning of such a theory. Status groups are not just categories made up by sociologists. They are the real groups in which we tend to find our friends, spend our free time, find out mates, and raise our kids. Marriage forces a couple to consolidate in one status group. This is not an absolute rule, but a tendency. The loose flow among social groups that single people, especially young single people, can enjoy (or suffer) tends to give way to a much more fixed and coherent social life when they marry, and especially when they have kids. A family is a little society which, in normal circumstances, all live in one status group. Families, especially networks of families, may be the basic unit of social closure.
I am groping toward an idea here, but I think I am on to something.