The Gathering Storm

The day after his victory in the debate, Galileo became seriously ill, and he
retreated to Salviati’s villa to recuperate. When he had the strength, Galileo summarized
in a treatise his views on floating bodies, and, with Salviati, returned to
the study of sunspots. They mapped the motion of large spots as the spots traveled
across the sun’s surface near the equator from west to east.
Then, in the spring of 1612, word came that Galileo and Salviati had a competitor. He called himself Apelles. (He was later identified as Father Christopher
Scheiner, a Jesuit professor of mathematics in Bavaria.) To Galileo’s dismay, Apelles
claimed that his observations of sunspots were the first, and explained the
spots as images of stars passing in front of the sun. Not only was the interloper
encroaching on Galileo’s priority claim, but he was also broadcasting a false interpretation
of the spots. Galileo always had an inclination to paranoia, and it
now had the upper hand. He sent a series of bold letters to Apelles through an
intermediary, and agreed with Cesi that the letters should be published in Rome
by the Academy of Lynxes. In these letters Galileo asserted for the first time his
adherence to the Copernican cosmology. As evidence he recalled his observations
of the planets: “I tell you that [Saturn] also, no less than the horned Venus agrees
admirably with the great Copernican system. Favorable winds are now blowing
on that system. Little reason remains to fear crosswinds and shadows on so bright
a guide.”
Galileo soon had another occasion to proclaim his belief in Copernicanism.
One of his disciples, Benedetto Castelli, occupied Galileo’s former post, the chair
of mathematics at Pisa. In a letter to Galileo, Castelli wrote that recently he had
had a disturbing interview with the pious Grand Duchess Christine. “Her Ladyship
began to argue against me by means of the Holy Scripture,” Castelli wrote.
Her particular concern was a passage from the Book of Joshua that tells of God
commanding the Sun to stand still so Joshua’s retreating enemies could not escape
into the night. Did this not support the doctrine that the Sun moved around
Earth and deny the Copernican claim that Earth moved and the Sun was
stationary?
Galileo sensed danger. The grand duchess was powerful, and he feared that
he was losing her support. For the first time he openly brought his Copernican
views to bear on theological issues. First he wrote a letter to Castelli. It was
sometimes a mistake, he wrote, to take the words of the Bible literally. The Bible
had to be interpreted in such a way that there was no contradiction with direct
observations: “The task of wise interpreters is to find true meanings of scriptural
passages that will agree with the evidence of sensory experience.” He argued that
God could have helped Joshua just as easily under the Copernican cosmology as
under the Ptolemaic.
The letter to Castelli, which was circulated and eventually published, brought
no critical response for more than a year. In the meantime, Galileo took more
drastic measures. He expanded the letter, emphasizing the primacy of observations
over doctrine when the two were in conflict, and addressed it directly to
Grand Duchess Christine. “The primary purpose of the Holy Writ is to worship
God and save souls,” he wrote. But “in disputes about natural phenomena, one
must not begin with the authority of scriptural passages, but with sensory experience
and necessary demonstrations.” He recalled that Cardinal Cesare Baronius
had once said, “The Bible tells us how to go to Heaven, not how the
heavens go.”
The first attack on Galileo from the pulpit came from a young Dominican priest
named Tommaso Caccini, who delivered a furious sermon centering on the miracle
of Joshua, and the futility of understanding such grand events without faith
in established doctrine. This was a turning point in the Galileo story. As Reston
puts it: “Italy’s most famous scientist, philosopher to the Grand Duke of Tuscany,
intimate of powerful cardinals in Rome, stood accused publicly of heresy from
an important pulpit, by a vigilante of the faith.” Caccini and Father Niccolo`Lorini, another Dominican priest, now took the Galileo matter to the Roman
Inquisition, presenting as evidence for heresy the letter to Castelli.
Galileo could not ignore these events. He would have to travel to Rome and
face the inquisitors, probably influenced by Cardinal Bellarmine, who had, four
years earlier, reported favorably on Galileo’s astronomical observations. But once
again Galileo was incapacitated for months by illness. Finally, in late 1615 he
set out for Rome.
As preparation for the inquisitors, a Vatican commission had examined the
Copernican doctrine and found that its propositions, such as placing the Sun at
the center of the universe, were “foolish and absurd and formally heretical.” On
February 25, 1616, the Inquisition met and received instructions from Pope Paul
to direct Galileo not to teach or defend or discuss Copernican doctrine. Disobedience
would bring imprisonment.
In the morning of the next day, Bellarmine and an inquisitor presented this
injunction to Galileo orally. Galileo accepted the decision without protest and
waited for the formal edict from the Vatican. That edict, when it came a few
weeks later, was strangely at odds with the judgment delivered earlier by Bellarmine.
It did not mention Galileo or his publications at all, but instead issued a
general restriction on Copernicanism: “It has come to the knowledge of the Sacred
Congregation that the false Pythagorean doctrine, namely, concerning the
movement of the Earth and immobility of the Sun, taught by Nicolaus Copernicus,
and altogether contrary to the Holy Scripture, is already spread about and
received by many persons. Therefore, lest any opinion of this kind insinuate itself
to the detriment of Catholic truth, the Congregation has decreed that the works
of Nicolaus Copernicus be suspended until they are corrected.”
Galileo, always an optimist, was encouraged by this turn of events. Despite
Bellarmine’s strict injunction, Galileo had escaped personal censure, and when
the “corrections” to Copernicus were spelled out they were minor. Galileo remained
in Rome for three months, and found occasions to be as outspoken as
ever. Finally, the Tuscan secretary of state advised him not to “tease the sleeping
dog further,” adding that there were “rumors we do not like.”