But the watchful Inquisition had already directed its attention to the man who had made such portentous discoveries in the heavens. How far this had gone we unfortunately do not exactly know. The only well authenticated indication we possess is the following notice in the protocols of the sittings of the Holy Congregation: “Feria iii. die, 17 Maii, 1611. Videatur an in Processu Doctoris Cæsaris Cremonini sit nominatus Galilaeus Philosophiæ ac Mathematicæ Professor.”[74] This is the first time that the name of Galileo occurs in the papers of the Congregation of the Holy Office, and it was in the midst of the applause which greeted him in the eternal city. Whether, and in what way, this official query was answered is not to be found in the documents of the Inquisition. But it looks ominous that there should be an inquiry about a connection between Galileo and Cremonini who was undergoing a trial. The causes and course of the trial of Cremonini by the Inquisition are not yet known. All that is known is that he was Professor of the philosophy of Aristotle at the University of Padua; and it appears from the letters of Sagredo to Galileo, that his lectures and writings had given rise to suspicions of atheism. For the rest, Cremonini was all his life one of Galileo’s most decided enemies.
The very triumphs of Galileo and his telescopic discoveries were the causes, to a great extent, of those ceaseless and relentless persecutions which were to restrict his labours and embitter his life. The Aristotelians perceived with rage and terror the revolutionary discoveries of this dangerous innovator were surely, if slowly, gaining ground. Every one of them, with its inevitable logical consequences, pulled down some important stone in the artistic structure of their views of nature; and unless some measures were taken to arrest the demolition, it was clear that the venerable edifice must fall and bury the inmates beneath the ruins. This must be averted at any price, even at the price of knowledge of the acts of nature. If Galileo’s reformed physics offered no point of attack, his astronomy did; not indeed in the honourable contest of scientific discussion, but by bringing theology into the field against science.
Galileo had never openly proclaimed his adoption of the earth’s double motion, but the demonstration of his telescopic observations alone sufficed to make it one of the burning questions of the day. What were the phases of Venus and Mercury, the motions of the solar spots, and above all Jupiter and his moons, this little world within our large one, as Galileo afterwards called it himself,[75] but telling proofs of the truth of the Copernican theory? The question of the two systems had been hitherto an exclusively scientific one. How else could the famous philosopher and astronomer Nicholas of Casa, who taught the double motion of the earth in the fifteenth century, have gained a cardinal’s hat? How could the German, Widmanstadt, have explained his theory, which was based upon the same principles, to Pope Clement VII. in 1533? How could learned men like Celio Calganini, Wurteis, and others, have given public lectures on the subject in Italy in the second half of the sixteenth century? Neither Casa, however, nor Widmanstadt, Calganini, Wurteis, nor even Copernicus, had ventured openly to declare war with the school of Aristotle, nor to overthrow by the crushing evidence of experiment the dogmas of natural science based upon philosophy and a priori arguments alone. These learned men had been tolerated because they fought with the same weapons as the followers of Ptolemy, logic and philosophy. They did not possess the powerful lever of direct evidence, because they were not acquainted with the telescope. But Galileo, with his fatal system of demonstration by observation of nature, was far too dangerous a foe. Peripateticism was no match for the home thrusts of arguments obvious to the senses, and its defenders were well aware that if they would not yield their position they must call in some other ally than mere science. And they adopted the means best adapted for putting a temporary drag on the wheels of truth, and for ruining Galileo; in order to prop up the failing authority of Aristotle they called in the inviolable authority of Holy Scripture!
This dragging of the Bible into what had previously been a purely scientific controversy, a proceeding which proved so fatal to Galileo, must not however, as has been done by several authors, be attributed solely to party considerations or even personal motives. This is absolutely false. Greatly as these factors were concerned in it, it must be admitted that at first they were only incidentally mixed up with it. The multitude of the learned, who still adhered entirely to the old system of the universe, and regarded the theories of Copernicus (not yet based on ocular demonstration) as mere fantasies, were really aghast at the telescopic discoveries of Galileo which threatened to overturn all their previous beliefs. The learned, and still more the semi-learned, world of Italy felt the ground tremble beneath their feet; and it seemed to them as if the foundations of all physics, mathematics, philosophy, and religion, were, with the authority of Aristotle, which had reigned for two thousand years, being borne to the grave. This did not present itself to them as progress but as sacrilege.
A young fanatic, the monk Sizy (the same who seven years later was broken on the wheel for political crimes at Paris), was the first to transfer what had been a purely scientific discussion to the slippery arena of theology. At the beginning of 1611 he published at Venice a work called “Dianoja Astronomica”[76] in answer to the “Sidereus Nuncius,” in which he asserted that the existence of the moons of Jupiter was incompatible with the doctrines of Holy Scripture. He appropriately dedicated his book to that semi-prince of the blood, John de’ Medici, who was known to be the mortal enemy of Galileo. The author, as we learn from his own work, was one of those contemptible men who carefully abstained from even looking through a telescope, although firmly convinced that the wonders announced by Galileo were not to be seen. Galileo did not vouchsafe to defend himself from this monkish attack any more than from Horky’s libel the year before. He contented himself with writing on the back of the title page of the copy still preserved in the National Library at Florence the following lines from Ariosto:—
“Soggiunse il duca: Non sarebbe onesto
Che io volessi la battaglia torre,
Di quel che m’ offerisco manifesto,
Quando ti piaccia, innanci agli occhi torre.”[77]