Michael Constantine Psellus (1018-1096 c.e.) was one of the more noted writers and philosophers of the Byzantine era. The byzantine domain was effectively the eastern Greek-speaking part of the old Roman Empire, centered on Byzantium (Constantinople, modern Istanbul), which split off from the Latin West in 364 C.E. Up until the arrival of the Arabs in the 7th century, the Byzantine empire was regarded as one of the strongest economies of Europe, particularly known for being the primary western terminus of the famous silk road from China.
Its intellectual legacies also derived from the long Greek occupation of Egypt, bringing with them a mix of Graeco-Egyptian magic and classical Greek philosophy. These influences later helped lay the foundations for the Italian renaissance, and the grimoire tradition. Psellus was a man of great intelligence, serving as a political advisor to a succession of Byzantine Emperors. He became the leading professor at the newly founded University of Constantinople, bearing the honorary title “Consul of the Philosophers” and was the driving force behind the university curriculum reform designed to emphasize the Greek classics, especially Homeric literature.
Psellus was adept in politics, astronomy, medicine, music, theology, jurisprudence, physics, grammar, magic and daemonology. Within this rare work, Psellus takes this knowledge and forms a bridge between the classical view of the daemon as a beneficial guiding spiritual presence, and the later Christian view of demons as intrinsically evil.