In surveying and reconsidering the critical impact of William James on affect theory, this essay follows Brian Massumi by returning to the field's key conceptual antagonism: the polemical separation of affect from emotion, and the undue theoretical entrenchment by which the unstructured and impersonal "autonomy" of the former (via Deleuze) has relegated the empirical embodiment of the latter (per James) to a marginal theoretical status. In originally describing a feeling "circuitry" underlining event perception, bodily response, and cognitive interpretation, James' work from 1890, far from being marginal, crucially shapes the subsequent affective ideas and language of the twentieth century in the work of such figures as John Dewey , Silvan Tomkins, and Antonio Damasio. After tracing this trajectory of influence, I invoke Spinoza to suggest implicit connections between the Deleuzian and Jamesian investments in Massumi's late work. From this perspective, an unexpected reconciliation of mind and body comes into view, one that recovers and portends further Jamesian possibilities for the affective study of embodied emotion.