Niklas Luhmann was a German sociologist who viewed society through the lens of complexity and systems theory. He believed that society is a system composed of communications, rather than individuals. While controversial, Luhmann argued that defining society as a system of communications, rather than people, allows us to study how social systems themselves communicate through things like protests. Luhmann developed a social systems theory grounded in concepts of autopoiesis, structural coupling, and operational closure to better understand how social, biological, psychological, and ecological systems interrelate and society functions.