PSELLOS (Psēllas), Constantine (Michael). - Politician at the court of Byzantium and polygraph, b. in 1018 at Constantinople, d. in 1078 (?).
Endowed with an immensely vast culture, he first held administrative and judicial offices; secretary at the court of Michael V (1041-42), he enjoyed the favor of Constantine Monomachus (1042-54), who in 1045 appointed him professor of philosophy at the Academy of Constantinople. Over the course of nine years he devoted himself to the renewal of Byzantine culture and of the Academy itself. Following the politico-religious events that disturbed relations between Byzantium and the Roman Church, in the last years of Monomachus he fell into disgrace and, like other officials, became a monk (taking the name Michael). Nevertheless the empress Theodora had occasion to resort several times to his counsels, and under her successors P. returned to the court, playing a preponderant part there. In 1071 he contributed to the election of Michael VII Ducas, formerly his pupil, and induced him to reject the proposals of reunion with the Roman Church. Having again and definitively fallen into disgrace, he died poor and obscure (the date of 1078, uncertain, is by some extended by two decades), himself the victim of those political arts and intrigues of which he had made ample and unscrupulous use.
Far more than to his political fortunes, the name of P. has remained linked to that vast movement of restoration of Platonic thought, of which he, albeit with eclectic tendencies, was the soul at a moment when Byzantine culture was decisively dominated by the Aristotelianism of Photius (v.). With this he returned to the speculative impetus of the three Cappadocians and especially of St. Gregory of Nazianzus (v.), the only one who, in his judgment, is to be preferred to Plato (cf. Sathas, Μεσαιωνική Βιβλιοθήκη, IV, p. 111). In this he may be called the precursor of the great Byzantine Platonists, who in the 15th century established in Medicean Florence, before Marsilio Ficino (v.), the cult of Plato. Among the works of P. are to be remembered: Expositio in Canticum canticorum; De omnifaria doctrina; Dialogus de daemonum energia seu operatione; De anima celebrex opiniones; In psychogoniam platonicam; Expositio in oracula magica quae a Zoroastro prodiere; Expositio in oracula Chaldaica; Compendium in logicam Aristotelis (where the mnemonic verses of the modes of the syllogism are reported).