“Dans la même Humanité”. The Concept of Universal Solidarity in the Philosophical Thought of Pierre Leroux

This essay situates Pierre Leroux’s (1797–1871) philosophical work within the broader conceptual difficulties that modern thought has encountered in defining solidarity. While modern philosophy has often treated solidarity as a vague political slogan or a non-binding ethical disposition, Leroux offers a rigorous and original attempt to re-found solidarity as a fully philosophical concept. Engaging with the tensions between universality and particularity, fact and value, and individual freedom and social obligation, Leroux reinterprets solidarity as the ontological and axiological principle underlying human coexistence. At the core of this rethinking is his critical reinterpretation of the Christian commandment to love one’s neighbor, which he reshapes into an objective logic of universal and reciprocal interdependence. Leroux constructs a speculative anthropology in which the individual and humanity are mutually constitutive. Solidarity thus emerges as the modern philosophical response to the need for a symbolic structure that sustains both individuality and sociality. This essay argues that Leroux’s thought—despite its marginalization— provides essential theoretical tools for overcoming the conceptual impasses of modern ethics and politics, and must be recognized as a crucial moment in the genealogy of a philosophical understanding of solidarity.