At a recent rhetoric conference in England, I started thinking about possible connections between Luhmann and Kenneth Burke. For rhetoricians, Burke’s most important concept is probably consubstantiality–“an acting-together within, and defined by, a common context.” In A Rhetoric of Motives, Burke wrote,
A is not identical with his colleague, B. But insofar as their interests are joined, A is identified with B. Or he may identify himself with B even when their interests are not joined, if he assumes they are, or is persuaded to believe so. . . In being identified with B, A is ‘substantially one’ with a person other than himself. Yet at the same time, he remains unique, an individual locus of motives. Thus he is both joined and separate, at once a distinct substance and consubstantial with another.
From a Luhmannian perspective, two psychic systems (Burke’s A and B above) are distinct but a communication/interaction system may form between them. The psychic systems are a necessary environmental factor of the communication system, but they are operationally excluded because a psychic system is not communication or a communicative event. Thus, we can translate Burke’s “individual locus of motives” as psychic system. The goal of rhetorical communication is consubstantiality, as in persuading a voter to identify with a politician or political party. For Burke, the key terms in rhetoric is identification.
With respect to social systems, one important case where consubstantiality occurs in the protest movements, which are social systems without explicit membership criteria. People align themselves with protest movements and contribute to the social systems autopoiesis by speaking in support of it, but there are no members in the sense of organization members.
Luhmann might have also spoken of collective social identities more broadly, for example, fans of a high school, college, or professional football team. The difference between this kind of social system and the protest movement is that fans of a sports team do not position themselves in opposition to society, but only in opposition to rival teams or rival fans. Particular fans come and go over the years, but the social system of fans can persist as long as the team exists. The system of fans does not consist of flesh and blood human beings; it is a communication system.
Identity politics is also about consubstantiality and social systems, and, of course, identity politics is closely associated with protest movements.
Of course Luhmann and Burke were not just saying the same thing with different words. Unlike Burkean theory, Luhmannian systems theory is anti-humanist. Two or more psychic systems can never be “substantially one.”