This essay is an analytical investigation of the ‘heroic’ emotions epitomized by both the finale and the slow movement of the Eroica symphony as an entry point into the topic of Beethoven and musical emotion. Whereas the history of emotions is a rapidly expanding field in the humanities, it has yet to take root in musicology or music theory. William Reddy’s The Navigation of Feeling (2001), a founding text of the history of emotion, explores the transformation of emotion in eighteenth-to-nineteenth-century France in terms of the politicization of sentimentality. Given the Eroica’s debt to the rhetoric of revolutionary France, it would seem plausible to map Reddy’s arguments onto the analysis of Beethoven’s formal processes. I will argue that musical emotion in Beethoven is pivotal between a culture of sociability and sentiment (after Hume and Smith) and the establishment of ‘emotion’ proper in the nineteenth century.