The first major annoyance of this theory, which stirred minds from the beginning, is its peculiar handling of the System/Environment Distinction.
Not only that the whole/part distinction – such as an understanding of people as part of society – has been permanently called into question as a blockade of knowledge of a high order. It is even replaced by a difference that no longer considers 'people' as particles of social systems.
Rather, what was classically in the social as in a Container (human bodies, which then contain something like the psyche) is now placed differently along the distinction between system and environment, namely in the environment of social systems.
On the one hand, 'people' (as a complex set of Body, mind, soul), on the other hand, the social system, which is not 'animated', not inhabited by consciousness, which neither lives nor is composed of living units and therefore naturally does not have perceptions.
Why this abstract thought, when one can experience every day that people are hanging around in society (where else?)? If one takes the word 'abstraction' literally, it means as much as deduction, and what is deducted in this high abstraction is the concreteness, the vividness of life and everyday life of the idea that it is people who enter into social relations with each other, communicate and cultivate communio in the sense of a unique community, which only homo sapiens sapiens can realize. Man – in contrast to traditional social theories – is seen as a being that cannot communicate. He is only relevant environment (co-world) of autonomous communicating units shielded against consciousness. Accordingly, humans are nothing more than mutual sources of noise for social systems.
And even worse: the theory that brings up this scenario assumes that this abstraction is not only one of the theory (a model, a method, a specific analytics), but that the object of research (the social) brings itself into the form of this abstraction, thus: is functioning abstraction. It is not about this abstraction not only a thinking preference, but something that actually happens in the social reality, a real abstraction (Realabstraktion).
To illustrate: the fact that we do not appear in universities as human beings, but only in our roles, is easily observable. And this is by no means simply annoying Alienation, but allows us not to have to bring in everything that constitutes us: much is none of the organization's business.
It was Luhmann who made the infamous rhetorical volte-face: "There are systems." The statement, then, that people do not communicate, that only communication communicates, that social systems are systems sui generis, which reproduce themselves autonomously (and, as it is called today, autopoietically), – according to their own laws, i.e. not according to desires that individuals bring to them – is serious, is meant literally.
The system theory claims validity in the subject area, that then (and this is the second annoyance) on the basis of a universalistic presumption, which in essence says that the abstractions of the theory are so 'steeply' laid out that no social (and today one would have to say: also no psychological) phenomenon can escape observation by the theory - including the theory itself. Accordingly, there is nothing that cannot be meaningfully thought about with the means of systems theory.
Thus, for example, a family as a social system is different from its social environments in that a Boundary is drawn between topics of family communication and what can and may be talked about outside the family. If this demarcation falls apart, the family dissolves.
But even this is not enough: The high abstractions, which the theory develops, are so abstract, so 'deducted', that one could not show anything, to which they refer. Already the key term of the theory, the system, does not denote a thing, an extension, a something that could be observed as a subject or object. Systems consist of invisible processes and structures.
To suggest an even slightly more complex thought: The system is a difference, or more precisely: it is the reproduction of a difference. That is, a system exists by being different from its environment
The definition reads accordingly: The system is the difference of system and environment. It is neither one side nor the other side of this distinction. One can justifiably speak of a transclassical 'object', of an 'unject' that cannot be perceived, measured, presented.