Ptolemaic system granted the Sun two motions. One of these, a slow annual progression from west to east, belonged strictly to the Sun itself. The other, more apparent, motion of the Sun across the sky over the course of the day – most probably the motion Joshua had sought to halt – actually belonged to the Ptolemaic Primum Mobile, the sphere of the highest sky, which spun all the other spheres containing Sun, Moon, planets and stars around the Earth every twenty-four hours. God’s stopping only the Sun would not have achieved Joshua’s desire. On the contrary, it would have made night arrive about four minutes early.
As Copernicus viewed the sky, however, the passage of day to night resulted from the turning of the Earth. Galileo agreed with Copernicus that the Earth somehow drew this motion from the Sun. Galileo had further observed the Sun to have its own monthly rotation, which he discovered during his studies of sunspots. Just as the light of the Sun illuminated all the planets, so too its motion energised them to pursue their orbits. Therefore, if God had stopped the Sun’s rotation, the Earth would have stopped, too, and the day stretched out to accommodate Joshua’s needs.
Later Galileo would point out that when the Sun stood still in the biblical account, it did so ‘in the middle of the sky’ – precisely where the Copernican system placed it. This reference to location could not be taken to mean the Sun had been standing in the high noontime position, for then Joshua would have found time enough to fight his battle without praying for a miracle to prolong the day.
Despite the strength of his argument, Galileo personally wished to abandon all such astronomical interpretations, on the grounds that the Bible spoke to a more important purpose. As he had once heard the late Vatican librarian Cesare Cardinal Baronio remark, the Bible was a book about how one goes to Heaven – not how Heaven goes.
‘I believe that the intention of Holy Writ was to persuade men of the truths necessary for salvation,’ Galileo continued his letter to Castelli, ‘such as neither science nor any other means could render credible, but only the voice of the Holy Spirit. But I do not think it necessary to believe that the same God who gave us our senses, our speech, our intellect, would have put aside the use of these, to teach us instead such things as with their help we could find out for ourselves, particularly in the case of these sciences of which there is not the smallest mention in the Scriptures; and, above all, in astronomy, of which so little notice is taken that the names of none of the planets are mentioned. Surely if the intention of the sacred scribes had been to teach the people astronomy, they would not have passed over the subject so completely.’
Castelli shared this exquisite exposition with friends and colleagues, who hand-copied it and forwarded it numerous times. Galileo now returned to predicting the positions of the Medicean satellites and to penning responses to various published attacks against his own published works. When his health faltered in March, Castelli, who had been begging Galileo to take better care of himself, stepped in to help him.
In the early days of summer, at the Convent of San Matteo in Arcetri, Virginia and Livia began to wear the dark-brown religious habits of the Franciscan orders. Although both children were still too young to take their vows, mother abbess Suor Ludovica Vinta told the ailing Galileo that she desired to see them appropriately outfitted before she relinquished her elected office.
Young girls received into the monastery before the age required by law shall have their hair cut off round and, their secular dress being laid aside, shall be clothed in religious garb as it shall seem fitting to the Abbess. But when they have reached the age required by law, they shall make their profession clothed after the manner of the others.
THE RULE OF SAINT CLARE, chapter II
Meanwhile Galileo’s letter to Castelli continued to circulate, travelling from hand to hand, and eventually falling into the wrong hands. On 21 December 1614, exactly one year to the day after Galileo wrote the letter, he found himself denounced from the pulpit of the Church of Santa Maria Novella, right in the city of Florence, by Tommaso Caccini, a hotheaded young Dominican priest with ties to the ‘pigeon league’.
Men of Galilee, why do ye stand looking up to heaven?
ACTS I: II
Beginning his sermon with this barb, Caccini moved quickly to the biblical text for that Advent Sunday, which happened to come from the Book of Joshua, and included the ‘Stand still, O sun’ command that had sparked Madama Cristina’s original complaint. Caccini wound up branding Galileo, Galileo’s followers, and all mathematicians in general ‘practitioners of diabolical arts…enemies of true religion’.
The vitriol of the language brought Caccini a reprimand, and Galileo a written apology from the preacher’s Dominican superior. But soon another Florentine Dominican, Niccolò Lorini, submitted a copy of Galileo’s now widely read letter to Castelli to an inquisitor general in Rome. Hearing this news, Galileo feared that crucial passages might have been altered (as indeed proved to be the case) either by mistakes in copying or through malevolent distortion. He sent a true copy to his friend at the Vatican, Piero Dini, who in turn copied it repeatedly for various cardinals who might help clear Galileo’s name.
Through the spring and summer of 1615, Galileo sustained yet another long bout of incapacitating illness – aggravated, perhaps, by his recognition of the forces arrayed against him. Indeed he saw himself the focus of a conspiracy. While bedridden, he recast his informal letter to Castelli into a much longer, more referenced treatise addressed to Madama Cristina herself. (Though no printer dared publish the Letter to the Grand Duchess Cristina until 1636, in Strasbourg, manuscript copies enjoyed a wide Italian readership.)
‘Some years ago,’ he began,
as Your Serene Highness well knows, I discovered in the heavens many things that had not been seen before our own age. The novelty of these things, as well as some consequences which followed from them in contradiction to the physical notions commonly held among academic philosophers, stirred up against me no small number of professors – as if I had placed these things in the sky with my own hands in order to upset Nature and overturn the sciences. They seemed to forget that the increase of known truths stimulates the investigation, establishment and growth of the arts; not their diminution or destruction.
Showing a greater fondness for their own opinions than for truth, they…hurled various charges and published numerous writings filled with vain arguments, and they made the grave mistake of sprinkling these with passages taken from places in the Bible which they had failed to understand properly, and which were ill suited to their purposes.
Even though Galileo directed these comments to Madama Cristina, he refrained from accusing her of the same injustices, which she had committed without malice. He reserved his venom for those others who used biblical passages they could not comprehend to condemn the worthy theory of Copernicus, which they had not read. He backed his position by quoting Saint Augustine, who advised moderation in piety and caution in judgment on complex issues, so as to avoid condemning hypotheses ‘that truth hereafter may reveal to be not contrary in any way to the sacred books of either the Old or the New Testament’. In the margins of his fifty-page letter, Galileo footnoted all the theological works he had consulted to construct his thesis concerning the use of biblical quotations in matters of science – allowing the likes of Saint Augustine, Tertullian, Saint Jerome, Saint Thomas Aquinas, Dionysius the Areopagite and Saint Ambrose to defend him against enemies who sought ‘to destroy me and everything mine by any means they can think of’.
Galileo felt he understood the motivation of his detractors: ‘Possibly because they are disturbed by the known truth of other propositions of mine which differ from those commonly held, and therefore mistrusting their defence so long as they confine themselves to the field of philosophy, these men have resolved to fabricate a shield for their fallacies out of the mantle of pretended religion and the authority of the Bible.’
The
