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Self reference/Luhmann/GLU: there are systems that relate through every of their operations to themselves: Social, psychological, organic systems that can observe the reality only because of this self-contact. - Self reference is present when the operation of the observation is included in what is referred to. - Self reference is neither analytic nor characteristic of a transcendental subject: the subject of the system theory is neither the human nor the subject. - Self-reference is not a tautology. - It does not refer directly to itself - e.g. if self-reference refers to a process: there is the distinction before/after.
Blind Spot/Luhmann/Reese-Schäfer: the failure of observation in all situations in which action must be taken or decided by you. - Action for security is certainly necessary and possible, but not as scientifically secured action. - Here, the system theory has its limits.
AU Cass 4
Definition self-reference/Luhmann: message: "What is in the system?". - Definition external reference: information (past or external system states). - Self-reference/external reference: hence there is the distinction between what a system can distinguish as the environment, and what an observer might see as environment.
Einführung in die Systemtheorie Heidelberg 1992
Die Kunst der Gesellschaft Frankfurt 1997