Galileo and His Judges

by F. R. Wegg-Prosser

The system of Copernicus was well received at Rome. A German disciple of his, John Albert Widmanstadt, in the year 1533, expounded it before Pope Clement VII., and produced a very favourable impression. Nor was the favour shown to Copernicus and his teaching ever withdrawn at Rome; his great work, “De Revolutionibus Orbium Cœlestium” (published, it is said, by the advice of Cardinal Schunberg, Bishop of Capua), was dedicated to the reigning Pope, Paul III.; nor does he appear to have received at any time the least rebuke or discouragement from the Holy See; he died, however, immediately after the printing of his book, in May, 1543.

Copernicus supposed the heavenly bodies, the Earth included, to revolve round the Sun in circles; but, as it was evident that they did not exactly do this, he used the theory of epicycles, and supposed each planet to make two revolutions in each epicycle for every revolution round the Sun. The true solution of the difficulty was due to Kepler, who lived in the next century, and who discovered that the planets moved in ellipses. Copernicus held, and, of course, held truly, that the Earth revolves on its axis, thereby causing the apparent diurnal motion of all the heavenly bodies from east to west.

Owing to his work having been the first of any great importance that maintained argumentatively the system called heliocentric, that is to say, in which the Sun is the real centre, round which the planets, including the Earth, revolve—for the treatise of Nicholas de Cusa does not appear to have had any extensive circulation—it is usual to speak of this system as the Copernican one, notwithstanding the errors from which its great author was unable to extricate himself, and which have long since been rectified by subsequent writers; so that even at this day we retain the name.

It is always useful in scientific subjects to introduce a definition; and this is my definition of the sense in which I employ the word Copernican, that it is simply as opposed to the system in which the Earth is the centre of the visible universe, and the Sun revolving about it. It is, in fact, less accurate but more convenient than the employment of the Greek words heliocentric and geocentric to denote the two systems. Greek words, no doubt, abound in our scientific vocabulary, as the following plainly show: astronomy, geology, geography, barometer, thermometer, microscope, telescope; but these have become naturalised in our language by long use, which heliocentric and geocentric have not as yet been.

After Copernicus there arose an astronomer of great merit, a Dane, Tycho Brahé by name, who attempted to start a fresh system—a modification, in fact, of that of Ptolemy. He made all the planets revolve round the Sun, and the Sun, accompanied by the planets, round the Earth. He deserves great credit for his painstaking observations; but he lived just before the invention of the telescope—or, at least, before it was used for astronomical purposes—and, therefore, was under an infinite disadvantage. His chief objection to the system of Copernicus was one at which a modern astronomer would smile, but which in those days seemed very weighty—namely, the enormous distance at which you must suppose the fixed stars to be situated, if it were true. The philosophers of that age did not like to admit such a waste of space as that which must intervene between the orbit of Saturn and the stars. And, on the Copernican theory, if the stars were not situated at an immense, almost infinite distance, they ought to appear to move in a way they certainly do not. Tycho Brahé was born in 1546. His theory never made much way; it had not, I imagine, sufficient elements of probability to recommend it generally; while the subsequent invention of the telescope, and the works of Kepler and Galileo, coming so soon after Tycho Brahé, prepared the way for that almost universal reception of the Copernican system which we have since witnessed. I shall refer later on to Tycho and his observations.

Such, then, was the state of astronomical theories in the latter part of the sixteenth century. Enlightened men like Copernicus had guessed—not accurately, it is true, but with a considerable approach to accuracy—at the real facts of the case. Tycho Brahé (who, I suspect, would have been converted to Copernicanism if his life had been prolonged) had suggested a system of compromise not likely, in the long run, to satisfy any thoughtful mind; while the bulk of men, even the learned, adhered to the old Ptolemaic scheme. Something, however, now occurred which was destined to work, sooner or later, a complete revolution in astronomy. The telescope was invented, and, at the same time, there arose a man who knew how to use it: that man was Galileo. He was not the inventor of it, for it was first constructed in Holland or Belgium; yet he had the energy and the skill to make a telescope, without having previously seen one, simply from the account he had heard of the instrument. The telescope that he constructed, which still bears his name, was the simplest possible. It was of a form now disused excepting for opera-glasses and for the far more powerful binocular field-glasses with which we are so familiar; but for telescopes properly so called an improved principle has long since been introduced. Galileo was the first man that ever, so far as we know, turned the telescope upon the heavens. How he was rewarded for his pains we shall presently see; and I propose to introduce a narrative of the principal events in his life, since there are no means for forming a judgment so valuable as having the facts of the case clearly before the mind.

For most of the facts I am indebted to M. Henri de l’Épinois, whose elaborate article in the French publication known as La Revue des Questions Historiques is of the highest value; as the author of this article has done what I suspect very few writers on Galileo have even attempted to do, namely, to inspect the documents preserved in the Vatican bearing on the process, some of which he gives at full length. Not having myself had the same advantage, I yet feel that I am treading on safe ground when I take my facts from M. de l’Épinois; for there is scarcely a statement that he makes for which he does not give his authority, whether from the documents just mentioned, or from Galileo’s own letters, or from other trustworthy evidence.[2]

To treat of Galileo, and to pass over the events which brought him into collision with the ecclesiastical authorities, would of course be impossible, nor is it easy to touch upon these matters without having some standpoint of one’s own—some principle to guide one, some basis from which to argue. I do not shrink from stating that I write from a Catholic standpoint; but without entering minutely into those subtle questions which are the province of the trained theologian.

As, however, a good deal of the narrative is connected with the action of the Roman Congregations, as they are termed, it may not be superfluous to explain briefly the nature of these institutions. They are formed by the selection of certain Cardinals, one of them acting as Prefect of the Congregation, to whom are added other ecclesiastics as consultors and as secretary. The Congregation of the Index, to which reference will hereafter be made, was instituted not long after the Council of Trent, by Pope St. Pius V., and has for its duty, as its name implies, the pointing out to the faithful people such books as they ought to abstain from reading. The chief consultor of the Index is the “Master of the Apostolic Palace,” whom I shall have occasion to mention more than once in connection with that Dialogue of Galileo which brought him into such serious disgrace at Rome.

The Congregation of the Inquisition—I need hardly say, not to be confounded with the Spanish tribunal of that name, which was founded at an earlier period, nor with similar tribunals in other countries—was erected in 1542 by Pope Paul III., and besides the other officials attached to it, had certain theologians called “qualifiers,” whose duty it was to give an opinion to the Congregation on questions submitted to them.