De operatione daemonum

...and having printed it, he asked me to provide it with a short preface so that it might not go forth alone and, as it were, ἀκέφαλος headless. This I could not and would not deny to a man who is both a friend and well-deserving in the field of literature. It seemed very opportune, however, to speak briefly and modestly about the age and writings of the author, about the origin of the Enthusiastae Enthusiasts/religious fanatics, and about their commerce, impudence, and idolomania obsession with idols with demons; and also about the bodies of demons, and finally about specters and the operations by which they delude the wretched. Zonaras therefore records (Ann. 18, c. 16)—for among others there is deep silence regarding him—that Psellus was a most honorable man and a prince of philosophers, and that he was a tutor in grammar, rhetoric, and philosophy to the Constantinopolitan Emperor, Michael Ducas, who was given the nickname Parapinacius (circa 1050 A.D.). He was a student of the Holy Scriptures and the Fathers, especially Basil, whose saying he is also reported to have explained in a booklet of scholia 1) See Bibl. Gr. vol. 10, p. 62.; and that he was a great admirer of Platonic discipline is indicated both by these facts and by most of his other monuments. For they say that he illustrated Plato's psychogonia the birth of the soul, Aristotle's Metaphysics, the Categories, the books On Interpretation, and Porphyry's Five Voices with clear commentaries.