Niklas Luhmann
A profile was written about Luhmann by Gotthard Bechmann and Nico Stehr (2002): infoamerica.org [2020-04-13].
It reveals who Luhmann was and what he dedicated his later life to doing: The analysis of modern society. He wrote voluminous books outlining a general theory of society as a whole, dividing it into chapters of Science, Art, Economics, Law, Politics and Religion.
He is also credited as the creator of the note-taking system Zettelkästen.