Francisco J. Varela was a student and collaborator of Humberto R. Maturana. Their pioneering collaboration on Autopoiesis and Cognition reestablished “processes of living” as the principle topic of biological explorations. This topic had dropped out of the discourse of biology after the work of Jacob von Uexküll. Autopoiesis brought a new framework to biology. I say framework because it was not a theory that predicted observable phenomena but a scaffold to pose and answer new kinds questions. In their The Tree of Knowledge, which connected the notion of autopoiesis to a variety of biological, evolutionary, cognitive, and, in a rudimentary way, linguistic and social phenomena, Francisco started to identify his contributions.