Celso e lo ius quod sibi debeatur iudicio persequendi: intorno al tema dell’azione in diritto romano

The paper examines Celsus’ definition of actio (nihil aliud est actio quam ius quod sibi debeatur iudicio persequendi) and places it at the centre of the debate on the relationship between action and subjective right. It addresses the main conceptual issues raised by the definition: the meaning of iudicium, the question of whether the definition is of general application, the significance of the textual variant (debeatur vs. debetur) between the Celsian version (D. 44.7.51 – Cels. 3 dig.) and Justinian’s (I. 4.6 pr.), as well as the purpose of the definition itself, which the author interprets as a functional elaboration aimed at addressing the issue of post litem contestatam fulfilment, in accordance with and in support of the Sabinian principle omnia iudicia absolutoria esse.