Why the Doubters Should Not Be Mocked
We should not ridicule those who hesitated and delayed in accepting the Copernican system. They had to accept, against the direct testimony of their senses, that the earth turns on its axis and also speeds through space at a frightening pace, and they had to follow a winding mathematical road only slightly less confusing than Ptolemy's. Until Kepler, Galileo and Newton set the new astronomy on a simpler and more exact foundation, its clear superiority over the old was not evident to minds; and even then people had to repeat of the sun the famous sentence Galileo is said to have spoken of the earth, "And yet it moves" (a traditional saying, not established fact). In the meantime Tycho Brahe rejected Copernicus's sun-centered hypothesis, finding his arguments against Ptolemy unconvincing. More remarkable was the speed with which many astronomers accepted the new theory, among them Rheticus, Osiander, John Field, John Dee and Erasmus Reinhold, who based his famous Prutenic Tables of the heavenly motions largely on Copernican hypotheses (1551).
The Church and the Theory
The Roman Catholic Church raised no objection so long as the new theory presented itself as a hypothesis. But the Inquisition struck a heavy blow when it put to death Giordano Bruno, who had dared to call Copernicus's hypothesis established truth and to set out its consequences for religion (the manner of his death is not detailed here). In 1616 the Congregation of the Index forbade reading On the Revolutions of the Heavenly Spheres "until corrected"; in 1620 it allowed Catholics to read only copies from which nine sentences presenting the theory as fact had been removed. In 1758 the book's name no longer appeared in the revised Index, and in 1828 the prohibition was expressly lifted.
A Blow to Theology and to Human Self-Image
The earth-centered theory fitted well with a theology that held everything was created for the sake of man. Now man felt he lived on a petty planet flung like a spinning ball through space, and the story of his life had shrunk to "a small local incident in the great collection of the world's news." What could heaven mean when "up" and "down" had lost all meaning and each turned into the other within half a day? In 1575 Hieronymus Wolf wrote to Tycho Brahe: "No blow to Christianity is so deadly as the claim of the infinite size and depth of the heavens," although Copernicus himself did not mention infinity in his teaching.
When men reflected on the results of the new scientific method, they must have wondered why the creator of this vast and orderly universe would send his son to the cross on our tiny globe. As if by the magic touch of that Polish churchman, the lovely poem of Christianity went up "like smoke into the sky," in Goethe's phrase. Sun-centered astronomy forced people to rethink their God, with traits less local and less like those of humans. Throughout history, this theory did theology the heaviest damage. The Copernican revolution therefore went far deeper than the Reformation, beside which the differences between the creeds of Catholics and Protestants began to seem small. It stepped beyond the age of the Reformation and laid the foundation of the Enlightenment: from Erasmus and Luther it passed to Voltaire, and then beyond Voltaire toward the nineteenth century and the pessimism of agnostic philosophy, the century that was to add the Darwinian disaster to the Copernican one. Only one social factor protected religion against such men: in each generation only a few grasp the consequences of their ideas. For most people Copernicus faded from memory while the sun went on "rising and setting." In 1581 Bishop Kromer built a monument to Copernicus against the inner wall of Frauenburg cathedral, beside his own tomb. In 1746 it was removed to make room for Bishop Szembek. Who knows?
Magellan and the Discovery of the Earth: Geology
Exploration of the unknown parts of the earth advanced faster than the mapping of the heavens, and its effects on religion and philosophy were nearly as revolutionary. Geology lagged behind the caravan of scientific progress, for the biblical account of creation so dominated minds that no one questioned it. Peter Martyr Vermigli, the half-Italian, half-English Reformer, said: "If an opinion contrary to what Genesis states about creation gains strength, all the promises of Christ are made void and our life and religion perish entirely." Apart from scattered remarks by Leonardo da Vinci, the most important geological work of the first half of the sixteenth century was by Georgius Agricola. Consider this passage from his On the Origin and Causes of Subterranean Things (Basel, 1546) on the origin of mountains (the source text is partly damaged and was reconstructed from context):
Hills and mountains, he says, are born of two causes: the force of water and the strength of wind, and also fire within the earth. Floods first wash away soft soil, later carry off harder soil, then roll over stones and wear them down; so within a few years they hollow out plains and slopes, and after many ages, from this constant digging, great elevations appear on the earth's surface. Rivers do the same by their rushing and washing, and so we often see them flowing between very high mountains of their own making, or near the shore of the sea that bounds them. Wind produces hills and mountains in two ways: by violently driving sand about, or when, driven into hidden hollows of the earth, it strains to burst and force a way out.
Agricola's work On the Nature of Fossils (1546) was the first systematic treatise on mineralogy; his other work, De Re Metallica, contained the first systematic study in stratigraphy and, as we saw earlier, gave the first scientific account of how mineral deposits form.
Ethnography and Leo Africanus
Ethnography produced two major works: Sebastian Munster's Cosmography (1544) and the Description of Africa (1550) by Leo Africanus. Hasan ibn Muhammad al-Wazzan was a Moor from Granada. He traveled through Africa as far south as the Sudan, with the same appetite for roaming the world and the soul as Ibn Battuta; he was captured by Christian corsairs and sent as a gift to Pope Leo X, who, on discovering his learning, freed him and took him into his service. In return Hasan became a Christian and took the name Leo. Over the next thirty years Leo Africanus composed his important book, first in Arabic and then in Italian. Before the book was printed he returned to Tunis, where he died in 1552, apparently in the faith of his ancestors.