No aspect of Jagadis Chandra Bose’s science is more enigmatic than his concern with the relationship between the living and nonliving, explored from 1900 through 1902. Elsewhere this writer called this the ‘middle Bose’ period since it separated Bose the physicist (1894–1900) from Bose the plant physiologist (1903 and after). The essence of his insight developed in this brief period was formerly termed by this writer the ‘Boseian thesis’ and summarized as ‘There is no discontinuity between the living and nonliving’. However, a more nuanced examination of three key texts published by Bose in this period, along with supplemental archival documents reveals that his articulation of the relationship between the living and nonliving evolved in subtle and daring ways culminating in an expression of the doctrine of panvitalism. This doctrine—that life pervades all matter—is an idea about the natural world. Thus, examining Bose’s panvitalism takes us into the realm of intellectual history: the close study of the meaning of Bose’s texts in order to understand his intention in exploring the relationship of the living and nonliving, the context of his investigation and its relation to the texts, and how he arrived at his panvitalist doctrine. The intellectual history of Bose’s panvitalism is the subject of this paper.