Building on the seminal essay "Problema e sistema nella controversia sul metodo giuridico" the article analyses the essence of the methodological approach of Luigi Mengoni, which is found in the revaluation of the topical thought in its interaction with the legal dogmatic, the concept of "living law" as the way in which the constitutional Court partecipates in the formation of constitutional law and the revaluation of a hermeneutic consciuosness to build a new legal order.