The purpose of this project is to make my historico-philosophical dissertation relevant in today’s increasingly important debate on sustainability. At the same time, this is where I aim at inserting my own voice. My contribution to the scholarship on Lewis Mumford is already clear: I have outlined the philosophy behind his works, a topic that has previously only been touched upon but never fully grasped. From the very start, however, I have had the aim of going beyond the research of a single human being in history by contributing to the research on the present course of human development; at the KLI, I will have an optimal opportunity to make my historical research useful and applicable in this context. Supported by Mumford’s evolutionary ideas, cognition and knowledge were paramount features of his philosophy on human-environment interaction. His contention that we must understand technology as a cultural-cognitive phenomenon—and reconceive it—if we are to achieve what is now called sustainability deserves to be considered, but not without reservation and scrutiny. The research that I have previously conducted sheds light on the present from the past; my research at the KLI will illuminate the past from the scientific standpoint of the present.