of Deity. They move in circles because the circle is the most perfect figure; it invariably returns into itself! The universe is bounded by the sphere of the fixed stars which is moved by the Deity himself, whilst the lower spheres are moved by various ethereal spirits.
This world theory seemed to be in harmony with the authorities of the age, Aristotle and the Bible, and at the same time to be in accord with the direct evidence of sense perception. This is why it required such a severe struggle to supplant it. It not only required the repudiation of venerable authorities, but even the most familiar sensory impressions. It was this profound revolution that constituted the stupendous task of the great Copernicus. The epistemological foundations of the ancient world view were unsettled by two men who had no acquaintance with its doctrine.
1. Nicholas Cusanus (1401-1464), a profound thinker with Neoplatonic and mystical tendencies, had even in the fifteenth century gone beyond the traditional view of a limited and stationary universe. Born in Cues (near Trier), he was educated by the “Brothers of the Common Life.” He afterwards continued his studies in Italy. He attained to high ecclesiastical positions and his philosophy has its starting point in theological speculations. In his doctrine of the Trinity he regards the Spirit as the uniting principle which combines the oppositions implied in the characters of Father and Son; spiritus sanctus est nexus infinitus. He afterwards discovers analogous principles in human knowledge and in nature generally.—Falckenberg’s Grundzüge der Philosophie des Nicholas Cusanus (Breslau, 1880) and M. Jacobi’s Das Weltegebaude des Kardinals Nicholas von Cues (1904) are splendid memoirs of this remarkable man.