I’ve always thought “lumpenproletariat” was a bit of a zombie term. Marx invented the term but never really theorized it, instead presenting it – on those few occasions when he used the term more than in passing – through images of heterogeneity:
Alongside decayed roués with dubious means of subsistence and of dubious origin, alongside ruined and adventurous offshoots of the bourgeoisie, were vagabonds, discharged soldiers, discharged jailbirds, escaped galley slaves, swindlers, mountebanks, lazzaroni, pickpockets, tricksters, gamblers, maquereaus, brothel keepers, porters, literati, organgrinders, ragpickers, knife grinders, tinkers, beggars – in short, the whole indefinite, disintegrated mass, thrown hither and thither, which the French term la bohème (The Eighteenth Brumaire of Louis Bonaparte).
Indeed, this untheorizable diversity, which “endlessly proliferates categories to encompass the spectacle of the metropolis,” may be the point of the term, as Peter Stallybrass argues in a dazzling essay on Marx and heterogeneity. But “lumpenproletariat” was taken up by Marxists as if it had a secure place within Marxist theory, as if the lumpenproletariat was a definite class with a particular role or characteristics; usually, this Marxist deployment of the term has served only to give a theoretical cover for moralism.