The author examines the role of the terms animus and corpus in the development of notion of possession. The path outlined by the main texts of roman jurists up to Paulus shows substantial continuity: the acquisition of possession animo is impossible, while the retention of possession animo is allowed for lands, where animus means the intention of dominus to return to the land. Since Paulus a change has occurred: the notion of animus and corpus ― which before were alternatives ― became intrinsic elements of possession.