The chapter is an intellectual biography of the early Bergson and lays out his immediate reasons for abandoning plans to earn a medical degree after completing his studies in philosophy. In the process, it shows Bergson’s later accounts of the early stages of his intellectual itinerary to at least be tinged by a retrospective illusion: Bergson did not start out as a psychologist-philosopher to become, via an interest in the philosophy of science, a metaphysician. A detailed overview of the institutional and intellectual landscape of nineteenth-century France demonstrates how the separation of disciplines in independent faculties of the French academy put immense pressure on philosophy to legitimate itself. This pressure was felt all the more acutely by those who, like the young Bergson, lacked economic, symbolic, and cultural capital. By abandoning the plan to study medicine, Bergson conformed to the institutional and doctrinal constraints placed on philosophy. This strategy of adaptation proved to be effective not only in the choice of topics he discussed in his dissertation but also in the way he moved toward, appropriated, and recast metaphysics as his career continued.