MICHAEL, a learned Christian of the 11th century, was, by birth, a Constantinopolitan of consular rank, and flourished under the emperor Constantine Monomachus. His genius and industry raised him far above the level of his contemporaries; and the female historian Anna Comnena speaks of him as one who had been more indebted for his attainments to his own excellent talent than to the instructions of his preceptors; adding, that having made himself master of all the wisdom of the Greeks and the Chaldeans, he was justly esteemed the most learned man of the age. Thus furnished, he became the chief instructor of the Constantinopolitan youth. He was at the same time the companion and the preceptor of the emperor, who was so captivated by the studies and amusements in which Psellos engaged him, that, according to Zonaras, he neglected the concerns of the empire. The Byzantine historians complain, that the emperor, deluded by the head of the philosophers (the title with which Psellos was honoured), lost the world. Meeting, towards the close of this life, with some disappointment, Psellos retired into a monastery, and soon afterwards died; the time of his death is uncertain. His works, which have been much celebrated, are, Commentaries upon Aristotle's Logic and Physics; a Compendium of Questions and Answers; and an Explanation of the Chaldean Oracles. The two latter works prove him to have been conversant, not only with Grecian, but with Oriental, philosophy.