For German Philosopher Martin Heidegger, “To be a work means to set up a world , and holds truth: Truth, as the clearing and concealing of beings, happens in being composed.” Taking an adult-centered online course as “the work” and a metaphor for a constructed world, the author uses an interdisciplinary approach to discuss the development of adults as learners. Presented at the Jean Piaget Society for the Study of Knowledge & Development 37th Annual Meeting, Amsterdam 31 May–2 June, 2007