Purpose: Through a series of critical discussions on Karl Popper's evolutionary analysis of learning and the non-authoritarian values it promotes, the purpose of this paper is to advocate a Popperian approach for building medical student knowledge. Specifically, it challenges positivist assumptions that permeate the design and management of many educational institutions, including teaching hospitals, by considering what does and does not happen when learning takes place. Design/ Methodology/Approach: To illustrate how Popper's approach differs from such a conception of learning, the paper examines the exchange between a preceptor (Sam) and a medical student (Lisa). The following exchange is based on the observations during a team meeting in a Canadian teaching hospital. The authors sent the transcript of the observation to Lisa for her comments. The statements in italics represent Lisa's additions. Pseudonyms are used to protect the identity of participants in the exchange. Findings: Popper's evolutionary analysis of learning and the Objective Knowledge Growth Framework provide a means of managing specific aspects of one's education through engaging in this learning process. Although this approach to teaching and decision making takes time to master, it does not require reconstituting existing institutional arrangements before it can be implemented in hospitals. Instead, it asks medical students, teachers and practitioners to be open to the theoretical underpinnings of the approach and to view knowledge growth as a process of systematic trial and error elimination. Originality/Value: This paper is original in its conceptualisation and may well become a classic in education circles. It draws on Popper's philosophical arguments and enters into a much needed discourse for teaching and learning.