This article critically analyzes Antonio Negri's democratic theory by exploring the theoretical significance of a concept that begins to appear in his writings after the 1990s, namely the concept of ‘love’. Negri's turn to love in the closing pages of his most recent books is puzzling, especially given his earlier recourse to notions of antagonistic struggle, direct confrontation and even violence. Using Jacques Derrida's conception of ‘the supplement’ for interpretive purposes, I argue that the concept of love not only enriches (...) Negri's account of democracy, but also points to a lack within his political thought. During the 1970s, as one of the leading figures of autonomist Marxism, Negri called for a radicalization of antagonism and the use of violence to ensure the political organization of the revolutionary subject without giving up on the emancipatory potential of ‘direct and immediate’ action. In his recent writings, Negri has supplemented the notion of ‘love’ for his earlier emphasis on antagonism to address autonomist Marxism's unresolved question of political organization. And yet, this turn to love comes at a price. Negri's understanding of love as the creative force of revolutionary consciousness leads him to erase the process of political contestation and mediation involved in the constitution of political struggles. Love, then, operates as a dangerous supplement, undermining Negri's commitment to multiplicity and diversity as central aspects of his democratic theory. (shrink)