Pletho, Giorgius Gemistus (c. 1355–1452)
PLETHO, GIORGIUS GEMISTUS
Giorgius Gemistus Pletho, the leading Byzantine scholar and philosopher of the fifteenth century, was born in Constantinople, the son of a cleric. Pletho is noted primarily for advocating a restoration of ancient Greek polytheism and, above all, for inspiring the interest of the Italian humanists of the quattrocento in the study of Plato. His studies followed the usual pattern of Byzantine education, emphasizing the classical Greek heritage. Influenced by certain of his teachers, Pletho became interested primarily in the philosophy of Plato, whose writings had again been brought into vogue in Byzantium during the eleventh-century renaissance under the influence of the Neoplatonic philosopher-statesman Michael Psellus. In 1380, Pletho went to the Turkish court at Brusa, or Adrianople, where he is reputed to have studied under the Jewish scholar Elisaeus. There Pletho presumably received training in the Muslim commentators on Aristotle, in Zoroastrianism, and in Chaldean astronomy and astrology and was encouraged by Elisaeus to further his study of Greek philosophy. Indeed, Gennadius Scholarius, who later condemned Pletho for his belief in polytheism, credits Elisaeus with leading Pletho to apostasy. About 1390, Elisaeus was burned at the stake by the Turks, probably for heterodoxy, and Pletho returned to Constantinople, from which he moved in 1393 to Mistra in the Peloponnese, near the ancient site of Sparta. It was at this administrative and cultural center of Mistra, which ranked second only to Constantinople and Thessalonica, that he spent the most important years of his life.
In 1438 Pletho appeared as adviser to the Greek delegation at the Council of Ferrara-Florence, convoked in order to effect a union between the Eastern and Western churches. An antiunionist and in some respects even anti-Christian, he took little interest in the council's proceedings. He preferred to consort with the Italian humanists, themselves fascinated by his knowledge of the works of Plato, which had for centuries been virtually unknown to the West. He left the council before the final ceremony of union to return to Mistra, where he remained until his death.
Pletho's works reveal a deep insight into Platonic philosophy and, remarkably, a devotion to Greece rather than to the crumbling Byzantine Empire. Many of his treatises aim at the revivification and restoration of Greece's ancient glory. In his famous tract "On the Differences between Plato and Aristotle," he asserts the superiority of Platonism to Aristotelianism, and his Laws, inspired by Plato's Laws and Republic, advocates a return to the polytheism of ancient Greece. Two memoirs based on a Platonic reconstruction of the state present a systematic plan of social and economic reform for Greece. Pletho felt that the collapse of the Byzantine Empire was due primarily to Christianity, the adoption of which had caused the alteration of the institutions of ancient Greece. In order to restore Greece to its former greatness it was necessary to foster a return to the ancient religion and to adopt a philosophy based on Platonic principles, which could serve as a guide in the process of governing. Pletho's numerous works include treatises on Zoroastrianism, Chaldean astronomy, music, history, rhetoric, the "philosophic virtues," geography, and various theological subjects. Among his theological writings is a treatise on the procession of the Holy Spirit composed in response to the Latin view presented at the Council of Ferrara-Florence.
Despite some modern opinion to the contrary, Pletho's apostasy from Christianity seems certain. Scholarius, his Aristotelian opponent, condemns him for advocating paganism in his Laws, and George of Trebizond quotes Pletho as asserting that a new religion, neither Christian nor Islamic but similar to that of the ancient Greeks, would sweep the world. Why then did Pletho attend the Council of Ferrara-Florence and evidently acquiesce in the act of union? Pletho was taken to the council by the Byzantine emperor John VIII, probably as a learned layman philosopher who could buttress the arguments of the theologians. Pletho's opposition to union was more on nationalistic grounds than dogmatic. As a patriot he feared that the consummation of union would precipitate a fresh Turkish attack on Constantinople. Moreover, he seemed to fear the Latinization of the Greeks, as for example in the possible suppression of Greek in favor of Latin in the ritual of the church. Finally, as a propagandist for the formation of a "Greek" nation and a restored Hellenism (in contrast to a "Byzantine" or, more correctly, "Roman" state), he was opposed to the international papal control implicit in the union of the two churches. His acceptance of the union can then be explained only as an act of political expediency with the aim of aiding Greece, not as the result of conviction that any particular doctrinal position was correct.
Almost every Greek humanist scholar of the fifteenth century was in some way influenced by Pletho, the most notable being his pupil, Cardinal Bessarion. A great many Italian humanists were also influenced by his writings and presence at the council. Through Pletho, ancient doctrines of the Chaldeans and Pythagoreans were transmitted to the West. More important, he set in motion at Florence the passionate interest in Platonism that was soon to permeate much of western Europe. Marsilio Ficino credits Pletho with inspiring Cosimo de' Medici to found the famous Platonic Academy. By introducing into Italy (especially through Paolo dal Pozzo Toscanelli) the geographical concepts of Strabo, Pletho may have prepared the ground for the correction of Ptolemy's geographical errors. Pletho consequently helped to alter the Renaissance conception of the configuration of Earth, thus indirectly influencing Christopher Columbus, for whom Strabo was an important authority. The high esteem in which Pletho was held by the Italian humanists is attested by the transfer of his remains from Mistra to Rimini, where they were interred in the Church of St. Francis.
See also Aristotelianism; Aristotle; Byzantine Philosophy; Ficino, Marsilio; Greek Academy; Humanism; Neoplatonism; Plato; Platonism and the Platonic Tradition; Pythagoras and Pythagoreanism; Zoroastrianism.
Traité des vertus. Edited by Brigitte Tambrun-Krasker. Athens: Academy of Athens, 1987.
Contra Scholarii pro Aristotele objections. Edited by E. V. Maltese. Leipzig: Teubner, 1988.
Oracles Chaldaïques. Recension de Georges Gémiste Pléthon. Edited by Brigitte Tambrun-Krasker. Athens: Academy of Athens, 1995.
Athanassiadi, Polymnia. "Byzantine Commentators on the Chaldaean Oracles: Psellos and Plethon." In Byzantine Philosophy and Its Ancient Sources, edited by Katerina Ierodiakonou, 237–252. Oxford: Oxford University Press, 2002.
Karamanolis, George. "Plethon and Scholarios on Aristotle." In Byzantine Philosophy and Its Ancient Sources, edited by Katerina Ierodiakonou, 253–282. Oxford: Oxford University Press, 2002.
Lagarde, B. "Le De Differentiis de Pléthon d' après l'autographe de la Marcienne." Byzantion 43 (1973): 312–343.
Tardieu, M. "Pléthon lecteur des Oracles." Mêtis 2 (1987): 141–164.
Woodhouse, C. M. Gemistos Plethon: The Last of the Hellenes. Oxford: Clarendon Press, 1986.
Deno J. Geanakoplos (1967)
Bibliography updated by Katerina Ierodiakonou (2005)