The Doctor explained, glancing at Vincenzo from time to time as if justifying his position to the old monk. “If the Earth truly rotated, what would happen to the air? There would be a violent, endless wind. All bodies not in contact with the ground would rush off in one direction. A falling stone would shoot off to the side as it left the hand. And yet, to the greatest precision which the eye can detect, and from the highest towers which we have, a stone falls straight down. There is no perceptible deviation from the vertical. The Earth must therefore, of necessity, be stationary, in accordance with the evidence of our own senses.”
“And the Sun as the centre of all things? With the Earth orbiting it?”
“If the Earth truly orbited the Sun, as Copernicus claimed, then the stars above would reflect this motion. Over the course of a year, each one would seem to move in a small path in the sky. A star at right angles to the zodiac would trace out a circle. One in the zodiacal plane would be seen to move backwards and forwards in a straight line. At intermediate celestial latitudes the stars would trace out ellipses. No such motion can be seen. Therefore the Earth cannot possibly be orbiting the Sun.”
“What of the hypothesis that the stars are like the Sun? That they are not confined to a sphere but scattered through infinite space?”
“If this were so, the stars would be at different distances from us. In that case the parallax effect which I have described would result in the constellations changing shape over the course of a year. They clearly do not. The Bear, Cassiopeia and Orion are unchanging in the sky. The eye and the mind are thus in harmony with the sacred teachings. The outermost limits of the World are set by the crystalline sphere in which the stars are embedded.”
“What then is your opinion of the structure of the World?”
“The structure of the Universe reaches its most perfect description in the Summa Theologica of Thomas Aquinas. The greatest imperfection exists here on Earth. But when we die, the souls of the blessed travel upwards through the heavenly spheres, each sphere of heaven being more perfect than the one before. Heaven, and God, with Christ at His right hand, lies beyond the sphere of fixed stars described by Aristotle. Three orders of angels exist here on Earth, three in the intermediate region, and three in the outermost heaven.”
Another cardinal, Mattucci, asked: “But are the complicated wanderings of the planets over the sky not best explained by the heliocentric doctrine? Do they not account for the retrograde motion of Mars as an optical illusion caused by an overtaking Earth? And is the system of Ptolemy not inferior in this respect?”
The professor said, “I cannot deny that in calculating the positions of the planets the Ptolemaic system is complicated. But even as a mathematical contrivance, the Copernican system works poorly. Copernicus created it on the basis of only a handful of observations. Further, my studies reveal that those observations are not reliable. Many of them have been corrupted by frequent copying from Ptolemy. The latter’s records are a mighty river to Copernicus’s trickling stream. The worst aspect of the Copernican hypothesis is the introduction of a moving centre for the Earth’s orbit, a completely arbitrary device whose sole purpose is to save the hypothesis.”
Mattucci persisted: “But the system is improved, is it not, by the invention of Johann Kepler that the planets move in ovals?”
“Have I a friend in court?” Vincenzo whispered.
Marcello wrinkled his nose sceptically.
The professor said, “That postulate can be made, but only as a computational device, not as a description of reality. Ellipses lack the appeal of circular symmetry. They destroy the harmony of the spheres. And for the planets to pursue these shapes, Kepler postulates the existence of occult forces proceeding from the Sun whereas, of course, the stars and planets are moved by angels.”
The Cardinal Mattucci leaned back to show that he was finished with the questioning. Terremoto took it up. “Doctor Paolicci, apart from the deficiencies of the heliocentric doctrine, which you have so clearly described, do your eyes and mind give you positive reasons for adhering to the Ptolemaic system?”
Paolicci allowed himself a brief, sly glance at Vincenzo. “It follows logically from the rational nature of the Creator. It cannot be denied that a rational, omnipotent Creator will build a perfect Universe. Of course the Prince of Darkness then induced the Fall from Grace, which is an imperfection, but that exploits the weakness of Man and does not affect the structure of the Universe. Only one object has perfect symmetry, in the three dimensions of length, breadth and height which we inhabit. That is a sphere. A perfect Universe built by a rational Creator must therefore be spherical. And only one type of motion is natural in a spherical universe, and that is circular motion. Otherwise the symmetry would be broken. That is why, of logical necessity, planetary motion must comprise circles, and circles upon circles.”
“You do not, then, accept the Bruno hypothesis that the Universe is infinite?”
“An infinite Universe is unthinkable.”
“And the plurality of worlds? Men on Bruno’s planets?”
“Such could not have been descended from Adam, nor could they obtain Christ’s redemption.”
Cardinal Borghese took up the questioning. He looked at the prisoner and his lawyer with open hostility before turning to the professor. “Doctor, you have told us that no contradiction is possible between science and faith.”
“No Christian can believe otherwise.”
“And if a contradiction were to arise?”
“Eminence, with respect, since no such contradiction is possible, your question is without meaning.”
“An apparent contradiction, then?”
“Since actual contradiction is impossible, the appearance of it can only arise in the mind of the Turk, or the Jew, or the heretic.”
Borghese turned to the notary. “Let it be recorded that Vincenzo is neither a Turk nor a Jew.”
A succession of witnesses from universities in Bologna, Pisa, Naples and Venice was then summoned, all saying much the same thing. By midday the room was becoming hot and stifling, and the court was adjourned for four hours.
In the apartment, the young advocate flopped on to the same settee which the Grand Duke’s secretary had occupied the previous week. “You have an impressive list of enemies,” he said.
Vincenzo gestured with open palms. “Academics are prone to jealousies. And much is at stake. But I also have many supporters.”
“Unfortunately, Father, your supporters dare not support you in court, while your enemies appear to have gained the ear of Boniface. Why else would you be on trial?” Marcello reached for an apple in a bowl and started to toss it playfully in the air. “Your old friend Fracastoro — the acquaintance of Foscarini.”
“Yes?”
“He is refusing to testify on your behalf, even on the matter of your piety and character. My courier tells me the man is terrified.”
“Have I no friends?” Vincenzo asked in despair.
“Perhaps one. The Cardinal Terremoto was told of your predicament with regard to witnesses. At once he instituted a diligent search and has at last found someone willing to testify to your character. I did not find your friend’s name.”
“Thank God for a small blessing. But it seems I will have to make the scientific case myself.”
The advocate took a bite at the apple. “A case which has already been rejected by this same Congregation when Galileo tried to make it a few years ago. Confess to error, Vincenzo. The alternatives are too horrible even to mention.”
“Can I retract the truth, my son?” Vincenzo headed for a small bedroom off the apartment. The advocate put the apple core in the fruit bowl, loosened the belt around his stomach and stretched out on the couch.