=Nicolas of Cusa= (1401–1464). Modern German scholars place Nicolas of Cusa (Nicolas Cusanus) with Bacon and Descartes, as the leaders of the modern philosophical movement. Nicolas lived two hundred years before Descartes and one hundred years before Bacon. The German estimate of him shows at least that he was modern in his thought, although he belongs in time to the Middle Ages for the most part. He lived when the Middle Ages were passing over into the Renaissance. His principal work, the _Idiota_, was published in 1450, when the Renaissance was on the threshold. He was certainly a forerunner of modern times. He was a German, a cardinal, and is now reverenced by liberal Catholics as one of their deepest thinkers. Cusanus was a scientist of no small merit. He died before the great discoveries were made; but he anticipated Copernicus in his belief that the earth rotated on its axis; he anticipated Bruno in conceiving space to be boundless and time unending; he proposed a reform in the calendar; he was the first to have a map of Germany engraved. He condemned the prevalent superstitions of the church and the use of magic in explaining nature events. Thus he anticipated the science of the time of Bacon, Hobbes, and Descartes, and transcended his own period. In other respects Cusanus belongs in this period with Bruno and Paracelsus. He did not seek to discover a new method; but he turned back to the revived traditional Greek systems for an explanation of the “new world.” He found in the mystic numbers of Plato and the Pythagoreans the principle of all scientific investigation. The world of nature phenomena must be accounted for by the spiritual world. Cusanus uses almost the identical language of Bruno, when he says that the world is the mirror of God and that man is an epitome of the universe. In the neo-Platonic spirit of the Humanists, he regarded the world as a soul-possessing and articulate Oneness. Although a scientist, he conceived science to be only a conjecture, which in its unreality reveals the inner interconnections of the real world――the world of the spirit.