Byzantine theologian and rhetorician, opponent of hesychasm, and advocate of union with the West; b. Constantinople; d. Lesbos, 1410. There is evidence of his relationship to John Calecas, Patriarch of Constantinople (1334–47). What little is known of his life is gathered mainly from his letters. While still a layman, he conducted a school that did not flourish, partly because of his extreme gentleness. About 1390 he came under the influence of Demetrius cydones, who introduced him to Aristotelian philosophy. Later Calecas taught himself Latin in order to read Thomas Aquinas. Forced to leave Constantinople because of his opposition to Hesychasm, he traveled through Italy and the Orient, entering the dominicans at Lesbos toward the end of his life. Latin scholasticism (medieval) is very evident in his works, which include: On Faith and the Principles of the Catholic Faith (Patrologia Graeca 152:429–661), a systematic explanation of theology in nine books written at the request of friends, and containing the pseudo-Augustinian Sermo de purgatorio and sermons concerning the Holy Eucharist attributed to Aquinas; treatises On the Substance and Operation of God (PG 152:283–428), against Gregory palamas; Against the Errors of the Greeks (PG 152:11–258); Against Joseph bryennios [G. Mercati, Notizie … ed altri appunti (Vatican 1930) 454–473]; Concerning the Procession of the Holy Spirit (PG 144:864–958), formerly attributed to Cydones; and also Greek translations of Boethius's De Trinitate, Anselm of Canterbury's Cur Deus homo, a Christmas Mass of the Ambrosian rite, and a Mass of the Holy Spirit from the Roman Missal.
Bibliography: Correspondance, ed. r. j. loenertz (Studi et Testi 152; 1950). r. j. loenertz, "Manuel Calécas: Sa vie et ses oeuvres," Archivum Fratrum Praedicatorum 17 (1947) 195–207. j. quÉtif and j. Échard, Scriptores Ordinis Praedicatorum 1.2: 718–720. k. krumbacher Geschichte der byzantinischen Literatur 110–111. h. g. beck, Kirche und theologische Literatur im byzantinischen Reich 740–741.
[m. c. hilferty]