John was a man of letters and an amateur philosopher. He and Theodora commissioned the archpriest Leo to go to Constantinople as ambassador and bring back as many Greek manuscripts as possible. Leo returned with the "Chronographia" of Theophanes, the "Antiquities of the Jews" by Flavius Josephus, "De Prodigiis" by Livy, the writings of Pseudo-Dionysius the Areopagite, and the "Historia Alexandri Magni". After Theodora's death, John took to reading and theorising, contemplation and translation into Latin, according to Leo. An interesting anecdote is told of this duke by Peter Damian. The legend probably dates from 981 and may have basis in historical fact. In a vision, John saw a group of devils leading a line of horses drawing carts full of hay for the purpose of burning Pandulf Ironhead, the deceased prince of Capua, and himself, still very alive. John decided then and there to abdicate, but only with the permission of the Emperor Otto II first. This he died before receiving.