In 1965, Fabro begins his weekly trips from Rome to the regional capital of Umbria. The first two years, he is the Dean of the Faculty of Education at the University of Perugia; from 1968 to 1981 he is professor of theoretical philosophy in the Faculty of Literature at the University. These are perhaps the most important moments of his teaching career; here, Fabro finds an environment where he is able to develop themes central to his teaching, such as the problems of being (esse), truth and liberty; here, Fabro presents some of his greatest works, such as his three-year course Analisi esistenziale della vita quotidiana. On the occasion of his retirement from teaching, at the request of the Dean and his colleagues, Fabro left his course notes, an intellectual legacy, a precious cultural autobiographical journey.

Fabro held the Chair of Theoretical Philosophy at the University of Perugia from 1965 until 1981, when he went off tenure; on November 1, 1986, he was put on pension, according to the old legislation.