CUSANUS, NICOLAUS (Nicholas of Cusa) (1401-1464), cardinal, theologian and scholar, the son of a boatman named Krypffs or Krebs, derived his name from his birthplace, Kues or Cusa, on the Moselle. He took his doctor's degree in law at Padua in 1423, and after studying theology at Cologne became archdeacon of Liege. He was a member of the council of Basel 0437), and dedicated to the assembly his De concordantia Cathol ics, in which he maintained the superiority of councils over popes, and assailed the genuineness of the False Decretals and the Donation of Constantine. Later, he zealously defended the su premacy of the pope. He was entrusted with various missions by the pope, being sent to Constantinople to bring about a union of the Eastern and Western churches. From 144o he was in Ger many, as papal legate at the diets of and 1446. In 1448, in recognition of his services, Nicholas V. raised him to the cardinalate, and in 145o he was appointed bishop of Brixen. In 1451 he was sent to Germany and the Netherlands to check ecclesiastical abuses, to purify monastic life and to promote the crusade. He died Aug. II, 1464.
Apart from his religious reforms, Cusanus is notable for his emphasis on the less predominant tendencies of mediaeval thought. Thus, like the early Oxford Franciscans, he exalts mathematics and experiment and objects to an excessive devotion to Aristotle. In his Reparatio Calendarii, presented to the council of Basel, he proposed the reform of the calendar after a method resembling that adopted by Gregory. In his De Quadratura Circuli he pro fessed to have solved the problem; and in his Coniectura de novissimis diebus he prophesied the end of the world in 1734. He anticipated Copernicus by maintaining a universal movement in which the earth, which is not the centre of the universe, is in volved. Celestial bodies are neither strictly circular in form nor in movement. In his principal work, De docta ignorantia (144o), supplemented by De Coniecturis libri duo (144o) he maintains that, because no two things are alike, all human knowledge is mere conjecture, and that man's wisdom is to recognize his ignorance. From scepticism he escapes by holding that God (the reality in which things participate and in which contradictions vanish) can be apprehended by intuition; hence the universe and man, who return to God by their love of unity, are called the contracted maximum. Cusanus thus laid himself open to the charge of pan theism brought against him in his own day. His chief philosoph ical doctrine was taken up by Giordano Bruno, who calls him the divine Cusanus.
The works of Cusanus were published at Basel, 1565. There are Eng. translations of The Idiot (165o), Conjecture de Ultimis diebus (1696), De Vision Dei (1646) and ch. 2. of Bk. 3. of De cord. Cath. dealing with the Donation of Constantine. See F. A. Scharpff's Der Kardinal and Bischof Nikolaus von Cusa als Reformator in Kirche, Reich and Philos. des is Jahrhund. (Tubingen, 1871) ; J. M. Dux, Der deutsche Kard. Nicolaus von Cusa and die Kirche seiner Zeit. (Regensburg, 1848) ; F. J. Clemens, Giordano Bruno and Nikolaus Cusanus (Bonn, 1847) ; E. van Steenberghe, Le Cardinal N. de Cusa (1920).