Von Foerster, Heinz. “Lethology a Theory of Learning and Knowing Vis à Vis Undeterminables, Undecidables, Unknowables”. Revista Universidad EAFIT 33, no. 107 (July 9, 2012): 13–30. Accessed November 11, 2026. https://publicaciones.eafit.edu.co/index.php/revista-universidad-eafit/article/view/1121.