The current crisis of neoliberalism has triggered a broad historical and political debate aimed at laying the foundations for establishing the institutions of a new social state. However, this debate is still based on the implicit equivalence between the social state and the welfare state. This article aims to question this common view, legitimized by legal litterature, by developing a historicalconceptual perspective based on the radicalization of the storia dei concetti developed by Giuseppe Duso and the Padua School. By putting the focus on the gap between concepts and reality, the article highlights the uniqueness of Herman Heller’s work in the context of the Weimar debates. Heller emerges as an essential reference for rethinking today a social state irreducible to the welfare state, as the new political science that he tried to forge through sociology to underpin socialism shifts the gaze of law from security to justice.