In dealing with these historic events will you allow me to repudiate once for all the slightest sectarian bias or meaning? I have nothing to do with Catholic or Protestant as such. I have nothing to do with the Church of Rome as such. I am dealing with the history of science. But historically at one period science and the Church came into conflict. It was not specially one church rather than another—it was the Church in general, the only one that then existed in those countries. Historically, I say, they came into conflict, and historically the Church was the conqueror. It got its way; and science, in the persons of Bruno, Galileo, and several others, was vanquished. Such being the facts, there is no help but to mention them in dealing with the history of science. Doubtless now the Church regards it as an unhappy victory, and gladly would ignore this painful struggle. This, however, is impossible. With their creed the churchmen of that day could act in no other way. They were bound to prosecute heresy, and they were bound to conquer in the struggle or be themselves shattered.
But let me insist on the fact that no one accuses the ecclesiastical courts of crime or evil motives. They attacked heresy after their manner, as the civil courts attacked witchcraft after their manner. Both erred grievously, but both acted with the best intentions.
We must remember, moreover, that his doctrines were scientifically heterodox, and the university professors of that day were probably quite as ready to condemn them as the Church was. To realize the position we must think of some subjects which to-day are scientifically heterodox, and of the customary attitude adopted toward them by persons of widely differing creeds.
If it be contended now, as it is, that the ecclesiastics treated Galileo well, I admit it freely: they treated him as well as they possibly could. They overcame him, and he recanted; but if he had not recanted, if he had persisted in his heresy, they would—well, they would still have treated his soul well, but they would have set fire to his body. Their mistake consisted not in cruelty, but in supposing themselves the arbiters of eternal truth; and by no amount of slurring and glossing over facts can they evade the responsibility assumed by them on account of this mistaken attitude.
We left Galileo standing at his telescope and beginning his survey of the heavens. We followed him indeed through a few of his first great discoveries—the discovery of the mountains and other variety of surface in the moon, of the nebulæ and a multitude of faint stars, and lastly of the four satellites of Jupiter.
This latter discovery made an immense sensation, and contributed its share to his removal from Padua, which quickly followed it. Before the end of the year 1610 Galileo had made another discovery—this time on Saturn. But to guard against the host of plagiarists and impostors he published it in the form of an anagram, which, at the request of the Emperor Rudolph—a request probably inspired by Kepler—he interpreted; it ran thus: The farthest planet is triple.
Very soon after he found that Venus was changing from a full-moon to a half-moon appearance. He announced this also by an anagram, and waited till it should become a crescent, which it did. This was a dreadful blow to the anti-Copernicans, for it removed the last lingering difficulty to the reception of the Copernican doctrine. Copernicus had predicted, indeed, a hundred years before, that, if ever our powers of sight were sufficiently enhanced, Venus and Mercury would be seen to have phases like the moon. And now Galileo with his telescope verifies the prediction to the letter.
Here was a triumph for the grand old monk, and a bitter morsel for his opponents.
Castelli writes, "This must now convince the most obstinate." But Galileo, with more experience, replies: "You almost make me laugh by saying that these clear observations are sufficient to convince the most obstinate; it seems you have yet to learn that long ago the observations were enough to convince those who are capable of reasoning and those who wish to learn the truth; but that to convince the obstinate and those who care for nothing beyond the vain applause of the senseless vulgar, not even the testimony of the stars would suffice, were they to descend on earth to speak for themselves. Let us, then, endeavor to procure some knowledge for ourselves, and rest contented with this sole satisfaction; but of advancing in popular opinion, or of gaining the assent of the book-philosophers, let us abandon both the hope and the desire."
What a year's work it had been! In twelve months observational astronomy had made such a bound as it has never made before or since.[31] Why did not others make any of these observations? Because no one could make telescopes like Galileo. He gathered pupils round him, however, and taught them how to work the lenses, so that gradually these instruments penetrated Europe, and astronomers everywhere verified his splendid discoveries.