Historian of medieval philosophy, his studies focused mainly on Cusano and Eckhart. An activist for tolerance and dialogue, he was awarded the “Grand Cross of Merit” by the President of the German Republic. Famous for Saturn and Melancholy (1983 Einaudi), written in collaboration with E. Panofsky and F. Sax, a masterly work that has become a classic in the history of philosophy, science and art. Refugee in Great Britain to escape the Nazi occupation, he was a key figure in saving several writings from the Warburg library, giving life to the Warburg Institute in London, one of the world’s leading centers for the study of art and culture.