Medical educators aim to train physicians with sound scientific knowledge, expert clinical skills and an ability to work effectively with patients, colleagues and health systems. Over the past century, educators have devoted considerable thought and effort to how medical education might be improved. Analysing the language used to describe these initiatives provides insight into assumptions and practices. The authors conducted a Foucauldian critical discourse analysis of prominent recurrent themes in the North American medical education literature. The assembled archive of texts included works of Abraham Flexner, articles from the journal Academic Medicine (including its predecessor journals) and major medical education reports. A series of recurring themes were identified, including the need to avoid over-specialization, the importance of generalism, and the need to broaden criteria for medical student selection. Analysis of these recurring themes allowed identification of a prominent and recurrent discourse of 'new.' This discourse places focus on the future, ignores the ongoing historical nature of issues, suggests a sense of urgency and enables the proposal of modest solutions. It emphasizes changes for individual future doctors, thereby limiting consideration of institutional and systemic factors. Using the image of a carousel, the regular return of themes can be seen as carousel ponies circling around repeatedly in medical education. Identification of this medical education carousel provides an opportunity for medical educators to understand the historical nature of calls for change, and to consider what kinds of reform might be required if they wish to avoid this repetition in the future.