Professor, he teaches History of philosophy at the University “La Sapienza” of Rome, where he got his degree in 1950. Lincei academician, he is founder and since 1964 director of the Institute of Studies of the National Research Board for the European Intellectual Lexicon, now Institute; he is a member of the scientific board of the Institute of the Italian Encyclopaedia. He is a member of the scientific board of the Institut de la Langue Française of Paris and he has been honorary president of the Société Internationale pour l’Etude de la Philosophie Médiévale (International Society for the Study of the Medieval History) since 1987. He is author of several works of philosophical kind. He is Fellow of the British Academy of Londra and Fellow of the American Academy of Arts and Sciences; he is Doctor honoris causa of the École Pratique des Hautes Études (Paris - Sorbonne, 1996). Knight of Grand Cross of the Italian Republic (2002).