Catholic Churchmen in Science [First Series] / Sketches of the Lives of Catholic Ecclesiastics Who Were Among the Great Founders in Science

by James J. Walsh

4. The distance from the earth to the sun compared with that from the earth to the fixed stars is extremely small.

5. The daily motion of the heavenly sphere is apparent that is, it is an effect of the rotary motion of the earth upon it axis.

6. The apparent motions of the moon and of the sun are so different because of the effect produced by the motion of the earth.

7. The movements of the earth account for the apparent retrograde motion and other irregularities of the movements of the planets. It is enough to assume that the earth alone moves, in order to explain all the other movements observed in the heavens.

It is no wonder that one of his bishop-friends, Frisio, writing to another bishop-friend, Dantisco, said: "If Copernicus succeeds in demonstrating the truth of his thesis--and we may well consider that he will from this prelude--he will give us a new heaven and a new earth." This shorter exposition of Copernicus's views was found in manuscript in the imperial library in Vienna only about a quarter of a century ago. [{33}] It is mentioned by Tycho Brahe in one of his works on astronomy in which he reviews the various contemporary advances made in the knowledge of the heavens.

The publication of Copernicus's great work, "De Revolutionibus Orbium Celestium," was delayed until he was advanced in years, because his astronomical opinions were constantly progressing; and, with the patience of true genius, he was not satisfied with anything less than the perfect expression of truth as he saw it. It has sometimes been said that it was delayed because Copernicus feared the storm of religious persecution which he foresaw it would surely arouse. How utterly without foundation is this pretence, which has unfortunately crept into serious history, can be seen from the fact that Pope Paul III accepted the dedication of the work; and of the twelve popes who immediately followed Paul not one even thought of proceeding against Copernicus's work. His teaching was never questioned by any of the Roman Congregations for nearly one hundred years after his death. Galileo's injudicious insistence in his presentation of Copernicus's doctrine, on the novelties of opinion that controverted long-established beliefs, was then responsible for the condemnation by the Congregation of the Index; and, as we shall see, this was not absolute, but only required that certain passages should be corrected. The corrections demanded were unimportant as regards the actual science, and [{34}] merely insisted that Copernicus's teaching was hypothesis and not yet actual demonstration.

It must not be forgotten, after all, that the reasons advanced by Copernicus for his idea of the movements of the planets were not supported by any absolute demonstration, but only by reasons from analogy. Nearly a hundred years later than his time, even after the first discoveries had been made by the newly constructed telescopes, in Galileo's day, there was no absolute proof of the true system of the heavens. The famous Jesuit astronomer, Father Secchi, says the reasons adduced by Galileo were no real proofs: they were only certain analogies, and by no means excluded the possibility of the contrary propositions with regard to the movements of the heavens being true. "None of the real proofs for the earth's rotation upon its axis were known at the time of Galileo, nor were there direct conclusive arguments for the earth's moving around the sun." Even Galileo himself confessed that he had not any strict demonstration of his views, such as Cardinal Bellarmine requested. He wrote to the Cardinal, "The system seems to be true;" and he gave as a reason that it corresponded to the phenomena.

According to the astronomers of the time, however, the old Ptolemaic system, in the shape in which it was explained by the Danish astronomer Tycho Brahe, who was acknowledged as the greatest of European astronomers, appeared to give quite a satisfactory explanation of the [{35}] phenomena observed. The English philosopher, Lord Bacon, more than a decade after Galileo's announcement, considered that there were certain phenomena in nature contrary to the Copernican theory, and so he rejected it altogether. This was within a few years of the condemnation by the Congregation at Rome. As pointed out by Father Heinzle, S.J., in his article on Galileo in the "Catholic World" for 1887, "science was so far from determining the question of the truth or falsity of either the Ptolemaic or the Copernican system that shortly before 1633, the year of Galileo's condemnation, a number of savants, such as Fromond in Louvain, Morin in Paris, Berigard in Pisa, Bartolinus in Copenhagen, and Scheiner in Rome, wrote against Copernicanism."

As we have said, Copernicus's book was not condemned unconditionally by the Roman authorities, but only until it should be corrected. This assured protection to the principal part of the work, and the warning issued by the Roman Congregation in the year 1820 particularizes the details that had to be corrected. It is interesting to note that whenever Copernicus is spoken of in this Monitum it is always in flattering terms as a "noble astrologer"--the word astrologer having at that time no unworthy meaning. The whole work is praised and its scientific quality acknowledged.

The passages requiring correction were not many. In the first book, at the beginning of the [{36}] fifth chapter, Copernicus made the declaration that "the immobility of the earth was not a decided question, but was still open to discussion." In place of these words it was suggested that the following should be inserted: "In order to explain the apparent motions of the celestial bodies, it is a matter of indifference whether we admit that the earth occupies a place in the middle of the heavens or not."