This chapter analyses the conceptual relevance of the notion of heterogeneity to the formulation of a radical politics in Robert Tressell’s classic working-class novel The Ragged-Trousered Philanthropists. It begins with a brief reconstruction of the social imaginaries of the mid-19th-century bourgeois novel in Britain, suggesting that the observations of urban opacity and unruly multiplicity found in authors such as Charles Dickens and Elizabeth Gaskell constitute a significant rehearsal of a socio-political grammar at the root of subsequent socialist developments. The chapter’s central claim is that it is with the uncovering of heterogeneity at the heart of the social, which 19th-century writing performs and a pioneering working-class text such as Tressell’s adopts, that the possibility of a discursive project of articulation emerges, reclaiming the category of class from any pre-determined or essentialist definition and opening it up to a logic of political contingency. It argues that this line of thinking, even if it never reaches the level of theoretical maturity found in continental Marxism at the turn of the century, and while its frame of reference remains that of late Victorian and Edwardian socialist debates in Britain, is comparable in some of its strategic conclusions to those of Marxist political thought in the early 20th century.