The papers presented in this volume in honour of Alfonso Maierù cover some of the major topics of his research area. The institutional and intellectual life of university training in the Middle Ages, including the peculiar tradition of related works, is the focus of the papers by Louis Jacques Bataillon, William J. Courtenay, Jacqueline Hamesse, Zénon Kaluza, Loris Sturlese and Olga Weijers. Three papers, by Jacopo Costa, Pasquale Porro and Thomas Ricklin, deal with philosophical problems in Dante"s Monarchia and Convivio. The complex interrelations between logic and the other main aspects of medieval philosophy, with a particular attention to theology, metaphysics and natural philosophy, are the core of the other papers by Stefano Caroti, Sten Ebbesen, Barbara Faes de Mottoni, Simo Knuuttila, Alain de Libera, Olga Lizzini, Costantino Marmo, Claude Panaccio, Ivan Bendwell, Irène Rosier-Catach, Lambert Marie de Rijk, Leonardo Sileo, Luisa Valente, and Albert Zimmer.