It’s difficult to overestimate the importance of Heinz von Foerster’s work on second-order observation to Luhmann’s systems theory. Check out von Foerster’s “For Niklas Luhmann: ‘How Recursive is Communication?‘” for an account of the latter working through their shared interest in seemingly intractable problems of perception and reference (von Foerster wrote the speech on the occasion of a celebration of Luhmann’s work held on the latter’s 66th birthday). As a bonus, you can also download here von Foerster’s “On Self-Organizing Systems and their Environments” and his “On Constructing a Reality,” two essays that provide concise overviews of his thinking on the social/epistemological vectors of perception.
