More than any other thinker before him, Norberto Bobbio was "the theorist of the social democratic century and of the recognition of social rights alongside those of politics and freedom. In this his legal background played a central role, leading him to examine all the potential of social transformation inherent in law. In his theoretical work he revisited the entire history of political philosophy and defined an extraordinarily clear map of its problems." Pier Paolo Portinaro retraces the precious legacy of the foremost Italian intellectual in the second half of the twentieth century. The most authentic interpreter of the century just past and of " the other Italy", that of civic commitment, home to Cattaneo, Salvemini and Gobetti.