The Galileo Affair

Author: William Shea (Galileo Chair of History of Science, University of Padua, Italy) and Mariano Artigas (Chair of Philosophy of Science, University of Navarra, Pamplona, Spain)
Published in: Unpublished text
Publication date: January 2006

 Contents

1. First Trip (1587) - JOB HUNTING

2. Second Trip (29 March 1611 - 4 June 1611) - ROMAN TRIUMPH

3. Third Trip (10 December 1615 - 4 June 1616) - ROMAN CLOUDS

4. Fourth Trip (22 April 1624 - 16 June 1624) - ROMAN SUNSHINE

5. Fifth Trip (3 May 1630 - 26 June 1630) - STAR-CROSSED HEAVENS

6. Sixth Trip (13 February 1633 - 6 July 1633) - FOUL WEATHER IN ROME

Notes

Summary

The authors have published Galileo in Rome. The Rise and Fall of an Uneasy Genius (New York: Oxford University Press, 2003), where they tell the story of the Galileo Affair following Galileo's six trips to Rome. Here they follow the same scheme. They stick to the well documented facts, and they also provide illustrations.

Text 

Galileo is known as the father of modern science and his clash with the ecclesiastical authorities of his day is perhaps the most dramatic incident in the history of the relationship between science and religion.¹ Galileo was condemned by the Roman Inquisition in 1633 for teaching that the Earth moves, and to the present day it is something of a puzzle why he was treated so harshly by the Roman Church. We shall try to see why in the light of documents that are now fully available since the complete opening of the Vatican Archives a few years ago.

Galileo was anxious to win approval in Rome where he went six times to meet the reigning Popes, and become acquainted with high-ranking cardinals and the leading figures of the literary and the scientific establishments. We shall use these six trips to structure our account.²

First Trip (1587) 
JOB HUNTING

Galileo left the University of Pisa in 1585 at the age of twenty-one, without any immediate prospect of a job. With a growing family and moderate means, his father expected him to earn his living. Galileo agreed, and he began giving private lessons in mathematics to students in Florence and Siena. He realized, however, that this would not get him far. What he needed was a permanent job and, in mathematics, this meant a position in a university. He decided to apply for the next vacancy that occurred, and in the meantime he knew what he had to do. First, produce an original piece of work and, second, get good references. The first was a condition for the second, and Galileo set to work on a paper on the centre of gravity of solids, a topic that was fashionable at the time. It was not published in a journal, because such means of communication did not exist as yet, but he sent copies to prominent mathematicians in Italy and abroad. One of these was Christopher Clavius, the Jesuit professor of mathematics at the Roman College , the foremost institution of higher learning in Catholic Europe. A letter of recommendation from Clavius would be worth its weight in gold and Galileo decided to go to Rome to meet him.

When Galileo arrived in the autumn of 1587 he discovered that urban renewal was under way, a process that had unexpectedly been set in motion a couple of years earlier when a mild-mannered and soft-spoken Franciscan friar became Pope Sixtus V. At 64, and with a reputation for indifferent health, Sixtus V has been elected as a "transitional" pontiff who would not upset anyone and would not live long. Events were to show otherwise. During the five years of his pontificate, Sixtus was more active than any pope had been within living memory. He was convinced that a shabby Rome was a disgrace to Christendom, and outrageous that Rome's 140,000 inhabitants should live huddled close to the Tiber, which often flooded and caused severe hardship and disease. Sixtus asked the simple question, Why should they not live on higher ground? The Roman hills of the Quirinal, the Esquiline, and the Viminal had been settled in ancient times, and Sixtus V made this possible again, laying out new streets and constructing a major aqueduct to solve the city's recurrent shortage of drinking water. He also rendered the streets of Rome safer than they had been for decades. He remodelled the Lateran and the Vatican palaces, and completed the dome of St. Peter's. Under his pontificate, Rome began to look like the one we admire today.

Galileo, like other visitors at the time, was struck by the fact that the papacy had been able to rescue Rome from its squalor and turn it into a dynamic capital. Rome had become important once more, and Galileo took this lesson to heart. Roman approval might prove crucial, and he was to return to the new city on five more occasions with this conviction in mind: in 1611, to have his telescopic discoveries approved; in 1615-1616, to promote Copernicanism; in 1624, to find out whether he could write a book on the motion of the Earth; in 1630, to secure permission to publish that book; and in 1633, to face the wrath of the Inquisition.

On this first trip in 1587, Galileo was made welcome by Clavius, who was favourably impressed by his work on the centre of gravity of solids, and the two mathematicians later carried on a friendly correspondence. More important still, Clavius promised to write a letter of recommendation whenever Galileo applied for a position at the University. The Jesuit was as good as his word, and in 1589, he helped Galileo get the Chair of Mathematics at the University of Pisa and, in 1592, the more prestigious one at the University of Padua.

Second Trip (29 March 1611 - 4 June 1611)
ROMAN TRIUMPH

In 1587, Galileo had been an impecunious 23-year-old, part-time teacher looking for a job. When he returned for the second time in 1611, he had become, at forty-seven, a famous professor. His telescopic discoveries had revealed that the surface of the Moon is covered with mountains and craters, that the stars are more numerous than anyone had imagined, that Jupiter has satellites, and that Venus has phases similar to those of the Moon. This had sent shockwaves throughout Europe. The imagination of Galileo's contemporaries had been fired, and the Granduke of Tuscany had named him his personal mathematician and philosopher. This meant that Galileo had been freed from the constraints of teaching and the drudgery of administration, but he now depended entirely on the goodwill of his young patron, Cosimo II¡, to whom he had taught mathematics. Cosimo was fond of his former teacher, but the radical distinction between ruler and subject was never questioned by either of them. Nor was it ambiguous. When Galileo went to Rome in 1611 he was expected to ask the Granduke's permission, and he had no hesitation in doing so.

Galileo had published his celestial discoveries in a slim Latin booklet entitled Sidereus Nuncius that can be rendered as Sidereal Messageor Sidereal Messenger. It became an instant bestseller, and everyone wanted to take a peep through the telescope. Galileo had intimated that the Earth moves around the Sun, but he had carefully avoided making this an issue. A Florentine philosopher by the name of Ludovico delle Colombe was the first to make a fuss about the motion of the Earth in a paper in which he claimed that it was contrary to Scripture. Delle Colombe had little to go by, beyond such verses as the one in Ecclesiastes, book 1, where we read, "The Sun rises, and sets, and returns to its place". There was one text, however, that could be turned into real dynamite. This is the passage inJoshua where the prophet is said to have arrested the motion of the Sun in order to provide more time for the Israelites to defeat their enemies. Clearly, if Joshua stopped the Sun in its tracks, it had to be in motion.

Galileo was reluctant to enter the theological arena. All he wanted was to have his discoveries recognised as genuine. Hence his desire to travel to the Eternal City and convince churchmen and scientists that his telescope spoke the truth. On 23 March 1611, he set off for Rome in style, in a litter provided by the Granduke and with two servants to attend to his needs. Six days later, on Holy Tuesday, he entered Rome as the guest of the Florentine Ambassador, Giovanni Niccolini, who gave him a set of rooms in the embassy that was located in the Palazzo Firenze near the Piazza Navona. Galileo lost no time and sprung into action. On the very day of his arrival he rushed to see Cardinal del Monte. The next day, 30 March, he went to the Roman College to meet Fr. Clavius and two younger Jesuits, Fr. Christopher Grienberger and Fr. On 2 April, the eve of Easter, Galileo called on Cardinal Maffeo Barberini, a Florentine like himself, and the man who was later to become Pope Urban VIII.

On 13 May, the Jesuits of the Roman College gave him the equivalent of a modern honorary doctorate in a lavish ceremony that was attended by several cardinals. He was lionised by Roman society and asked to give lectures in the numerous salons that acted as informal academies. He was also invited to display his instrument at the home of notables, often in the setting of an evening meal and to the accompaniment of music. One such banquet, at which he was the guest of honour, was to have lasting consequences. It was organised by Prince Federico Cesi, the founder of the Accademia dei Lincei (Academy of the Lynxes). Galileo had brought his instrument, which was used in broad daylight to examine features of buildings that were invisible to the naked eye and, after the meal when it became dark, at the night sky. It is on this occasion that the new device, which Galileo had called perspicillum(lens) in Latin and occhiale (spyglass) in Italian, was given the name telescope (from the Greek for "seeing-afar") by the Greek scholar Giovanni Demesiani or perhaps by Cesi himself. A few days later, Galileo was made a member of the Accademia dei Lincei, a privilege that had only been conferred upon four other persons since its foundation in 1603. A reliable patron, Cesi was to finance the publication of Galileo's Letters on the Sunspots in 1613 and his Assayer in 1623. He fully intended to publish Galileo's masterpiece, theDialogue on the Two Chief World Systems, but he died before the work had run the gauntlet of censorship and was licensed for print. Had Cesi been alive in 1632 when the book finally appeared it might have sailed past the shoals of the Inquisition.

On 22 April, Galileo was granted an audience with the Pope, Paul V. On the very same day, he reported to his friend, Filippo Salviati: "This morning I went to pay my respects to his Holiness, and I was introduced by his Excellency, our illustrious Ambassador, who told me that I had been treated with exceptional favour because his Holiness would not let me say a word kneeling (as protocol required) but immediately told me to rise.Paul V was a canon lawyer by training, and he did not brook any behaviour that appeared to challenge the legal authority of the Church. Not particularly gifted in diplomacy, his treatment of Galileo seems to have been a gesture of unusual courtesy. Following in the footsteps of Sixtus V, Paul V was bent on modernising Rome. He set himself the immense task of completing St. Peter's, and when Galileo arrived in Rome the imposing façade by Carlo Maderna was nearing completion, although the huge inscription that runs across the front, PAULUS V BORGHESIUS ROMANUS, was something he was only to see on his next trip in 1615.

When Galileo left Rome on Saturday, 4 June 1611, he was happy with the result of his trip. He could also look forward to the Granduke's pleasure when he would read the glowing report that Cardinal Francesco del Monte had prepared for him: "During his stay in Rome, Galileo has given great pleasure and, I believe, received as much. He showed off his discoveries so well that those who are competent here all agreed that they were not only true and well founded but simply marvellous. Were we still living in the ancient Roman Republic, I am certain that a statue would be erected in his honour on the Capitol."³

This was no light praise. The only other equestrian statue on the Capitol is that of the emperor Marcus Aurelius!

Third Trip (10 December 1615 - 4 June 1616)
ROMAN CLOUDS

Galileo was paid on the budget of the University of Pisa, but he had no intention of lecturing and considered himself a research professor. He engineered an appointment for his favourite student, the Benedictine priest, Benedetto Castelli, and had him teach the usual undergraduate courses. When Castelli arrived in Pisa in the autumn of 1613, the Overseer of the University, told him that he was under no circumstances to discuss the motion of the Earth in his lectures. Castelli replied that he had no such intention, wisely adding that his own teacher in Padua, Galileo, had never done so.

Shortly thereafter, the Tuscan court arrived in Pisa for their annual visit, and Cosimo II invited Castelli to his table. When he arrived on Thursday, 12 December 1613, Castelli found the Granduke's mother, Christina of Lorraine, the Granduke's wife, Maria Maddalena, and several other guests including Prof. Cosimo Boscaglia, a colleague from the University of Pisa. Here is Castelli's account of the conversation as he communicated it to Galileo a couple of days later: "Thursday morning I was at table with our Patrons and when asked by the Granduke about the University, I gave him a detailed account of everything, with which he showed himself much pleased. He asked me if I had a telescope. I said yes, and I began to tell about an observation of the Medicean planets I had made the night before. Madama Christina wanted to know their position, whereupon the talk turned to the reasons for their being real objects and not illusions produced by the telescope".

Professor Boscaglia agreed that they were indeed real, and Castelli proceeded to tell them about Galileo's determination of the orbits of the satellites of Jupiter. The meal ended pleasantly, and Castelli took his leave, but "hardly had I come out of the palace," the letter continues, "when I was overtaken by the porter of Madama Christina, who called me back. But before I tell you what followed, you must first know that while we were at table Doctor Boscaglia had had Madama's ear for a while, and while conceding as real all the things you have discovered in the sky, he added that the motion of the Earth was somehow incredible, and could not take place mainly because it went against Holy Scripture."

Madama Christina was a devout Catholic who listened to her confessor and was devoted to the Pope even when His Holiness' interests might be at variance with those of the Tuscan government. She also knew her Bible and could refer to the Book of Joshua where the Sun, not the Earth, is ordered to stop in its tracks. Upon re-entering the Palace, Castelli found that some of the guests were still there including Professor Boscaglia, Paolo Giordano Orsini, a cousin of the Grand Duke, and Antonio de Medici, an adopted son of the Duke's grandfather, Cosimo I. "The Grand Duchess," Castelli went on, "began to argue Holy Scripture against me. Thereupon, having made suitable disclaimers, I began to play the theologian with such assurance and dignity that it would have done you good to hear me. Don Antonio assisted me, giving me such heart that instead of being dismayed by the majesty of Their Highnesses I carried things off like a paladin. I quite won over the Granduke and his Archduchess, while Don Paolo came to my assistance with a very apt quotation from Scripture. Only Madama Christina remained against me, but from her manner 1 judged that she did this only to hear my replies. Professor Boscaglia never said a word."⁴

Although he was not displeased with Castelli's answers, Galileo's mind was not completely at rest, and he saw that he must intervene. Within a week he put down his own ideas on paper in the form of a long Letter to Castelli, which could be shown to friends. This was to be his first but not his last incursion into theology. Galileo expanded his letter to Castelli into a small treatise that he addressed to the Granduchess, and which became known as the Letter to Christina of Lorraine. It was only published in 1635, in Strasbourg, along with a Latin translation by a Protestant scholar.

Galileo saw no conflict between science and religion, and he was anxious that no line of battle should be drawn between the two. He readily admitted that Scripture cannot err, but this did not imply that its interpreters were always right. This was particularly the case when they insisted on the literal meaning. For in this way, we would have to say that God has hands and feet and eyes, and human emotions such as anger, regret, hatred, and sometimes forgetfulness of the past and ignorance of the future. Galileo argued that this way of speaking had been introduced into the Bible for the sake of the masses, and only to help them in matters concerning salvation. "Sacred Scripture and nature," he declared, "both proceed alike from the Divine Word, the former as a dictate of the Holy Spirit and the latter as the obedient executrix of God's commands."⁵ No truth discovered in nature can contradict the Bible. Indeed Copernican astronomy even makes the miracle of Josuah arresting the Sun easier to understand, according to Galileo, because if the Sun was seen to stop, this indicated that the Earth no longer revolved and, therefore, that the day had been automatically prolonged. This explanation of the miracle of Josuah, however ingenious, was highly speculative, and it cast Galileo in the dangerous role of telling theologians how to interpret Scripture.

On 7 February 1615, Niccolò Lorini, a Florentine Dominican friar, sent a copy of the Letter to Castelli to cardinal Paolo Camillo Sfondrati, Prefect of the Congregation of the Index in Rome, and an enquiry was opened in the Inquisition, but the issue was left pending. Nonetheless, rumours began to fly, and Galileo thought that it would be wise to go personally to Rome to silence his critics. He now believed that he had a valid physical proof for the motion of the Earth, an argument from the tides to which we shall come in a moment. Meanwhile someone else threw his hat in the ring. Paolo Antonio Foscarini, an otherwise unknown friar from southern Italy, wrote an essay on the compatibility of Copernicanism with Scripture and sent a complimentary copy to an influential member of the Inquisition, Cardinal Robert Bellarmine. The remarkable thing is that the Cardinal took time off from a very busy schedule to write, in his own hand, a thoughtful and considerate reply on 12 April 1615.

Assuming, like most of his contemporaries, that Copernicus had put forward his system merely as a calculating device to determine the position of the planets, Bellarmine began by commending the prudence that Foscarini and Galileo had displayed "in speaking only hypothetically, as I have always believed Copernicus did". For good measure the Cardinal added that the Council of Trent ruled out interpretations of Scripture that were contrary to the consensus of the Church Fathers, all of whom took the passages about the Sun's motion literally.

Because of its great importance in the subsequent discussion, Cardinal Bellarmine's letter deserves to be quoted extensively: "The words,the Sun also rises and the Sun goes down and hasten to its place where he arose, etc. were those of Salomon, who not only spoke by divine inspiration but was a man wise above all others and most learned in the human sciences and in the knowledge of all created things. His wisdom was from God, and it is not likely that he would affirm something that went against a truth that was already demonstrated, or likely to be. Now if you tell me that Solomon spoke only according to appearances, and that it seems to us that the Sun goes around when actually it is the Earth that moves, as it seems to one on a ship that the shore moves away from the ship, I shall answer that though it may appear to a voyager as if the shore were receding from the vessel on which he stands rather than the vessel from the shore, yet he knows this to be an illusion and is able to correct it because he sees clearly that it is the ship and not the shore that is moving. But as to the Sun and the Earth, a wise man has no need to correct his judgement, for his experience tells him plainly that the Earth is standing still and that his eyes are not deceived when they report that the Sun, the Moon and the stars are in motion."⁶

Bellarmine did not consider whether biblical statements about the motion of the Sun were just an unexamined assumption, but immediately expressed his own theological conviction that there can be no errors in Holy Writ. For him it was no answer to say that the motion of the Earth is not a matter of faith because what is at stake is nor the subject matter but the veracity of its source, namely the Holy Spirit. On Bellarmine's view, it is just as heretical to deny that Abraham had two sons and Jacob twelve as to deny that Christ was born of a virgin. Furthermore, Bellarmine stressed the logical point that although Copernicanism might work as an astronomical system, this did not imply that it was physically true. In case of doubt it would not be reasonable to ask the Church to dismiss the common interpretation of Scripture. If there was a proof of the motion of the Earth, then the Cardinal agreed that we would have to carefully examine the scriptural passages that seem contrary and confess that we do not understand them rather than say that something that has been proved is false. But he had, as yet, seen no such proof.

Lest we misunderstand the historical situation, we must bear in mind that Galileo, whom we celebrate as the Father of the scientific revolution had already entered his fifty-third year without having published the great Copernican book that he had advertised as forthcoming in 1610. His reputation rested on his telescopic discoveries, admittedly brilliant but due in large part to the availability of good lenses in the Venetian Republic. He had seen new things sooner and perhaps a little better than others, but this was due to an optical tube rather than any mastery of optics, about which he knew little. He was undoubtedly a versatile writer and an entertaining speaker, but professionals considered him a gifted amateur when it came to philosophy. There was no indication that he was a particularly good teacher, and he never lectured at the University of Pisa, where his colleagues complained that he was overpaid. Furthermore, he had no training whatsoever in theology. He had been asked, very politely, to prove that the Earth really moved before demanding that the Church reinterpret the Scriptures. Instead of making a gesture to comply, he had become increasingly annoyed at what seemed to him the pig-headedness of the academic world. Galileo was getting restive and felt that he could carry the day if he were allowed to use his tongue instead of his pen. This is why he had to go to Rome. He felt this was the only honourable course, and he believed that it was also in the best interest of the Church. Cardinals Robert Bellarmine and Maffeo Barberini declared that Copernicus had proposed his theory as pure speculation. But they were wrong, as Galileo was anxious to let them know.

Galileo arrived in Rome on 10 December 1615, and immediately took up the cudgels as we know from a letter of Monsignor Querengo to Cardinal d'Este: "You would be delighted to hear Galileo argue, as he often does, in the midst of some fifteen or twenty persons who attack him vigorously, now in one house, now in another. But he is so well buttressed that he laughs them off; and although the novelty of his opinion leaves people unpersuaded, yet he shows that most of the arguments, with which his opponents try to overthrow him, are spurious. Monday in particular, in the house of Federico Ghislieri, he performed marvellous feats. What I liked most was that, before answering objections, he improved on them and added even better ones, so that, when he demolished them, his opponents looked all the more ridiculous."⁷

Galileo's eloquence and his brilliant repartees made for great sport in the literary circles to which he was repeatedly invited, but the applause that he won had little to do with a genuine understanding of the nature of the argument. Most people enjoyed the liveliness of the discussion but treated the whole matter as a suitable topic for a debating society rather than a serious scientific enquiry.

The melancholy outcome of Galileo's campaign in favour of Copernicanism was that the Holy Office took an interest. On Thursday, 19 February, the Holy Office decided to submit to a panel of eleven experts the following propositions: "The Sun is at the centre of the world and hence immovable of local motion. The Earth is not the centre of the world, nor immovable, but moves according to the whole of itself, also with a diurnal motion". The consultants met on Wednesday, 24 February, and made the following recommendations: (1) the notion that the Sun is at the centre of the world and at rest is "foolish and absurd in philosophy, and formally heretical, inasmuch as it expressly contradicts the doctrine of the Holy Scripture in many passages, both in their literal meaning and according to the general interpretation of the Fathers and Doctors"; (2) the statement that the Earth moves, "deserves the same censure in philosophy and, as regards theological truth, is at least erroneous in faith."⁸ The experts could only advise; all decisions rested with the Pope and the cardinal inquisitors. The very next day, on Thursday, 25 February 1616 the following course of action was decided upon: Bellarmine was to summon Galileo and enjoin him to abandon Copernicanism. According to an unsigned memorandum, on 26 February 1616 Galileo was called in by Cardinal Bellarmine in the presence of the Commissioner of the Holy Office and two guests, and informed, on behalf of His Holiness the Pope and the Congregation of the Holy Office, to relinquish altogether the theory that the Sun is at the centre of the world and at rest and that the Earth moves; nor henceforth to hold, teach, or defend it in any way verbally or in writing. Otherwise proceedings would be taken against him by the Holy Office. Galileo acquiesced and promised to obey. This minute was probably penned by some zealous official (who speaks in the first person) who wanted to record that the Commissioner had actually stepped in to give Galileo a strict injunction to relinquish Copernicanism altogether.

We now move from the Holy Office to the Congregation of the Index, where five Cardinals, including Maffeo Barberini, met in Bellarmine's office on Tuesday, 1 March 1616. After discussion, they recommended: that the works they had been asked to judge be censured, but not exactly in the terms that had been proposed by the experts. At Cardinal Barberini's request, Copernicanism was not described as "heretical," but as false and contrary to the Scriptures. Copernicus' De Revolutionibus was taken out of circulation until corrections were made. Galileo was not mentioned.

Transparency is a great virtue. Things that are done in the open are less likely to be distorted or used in ways that were not intended. But privacy is also an important aspect of social life, and the most liberal citizen will value confidentiality when his purse or his life is at stake. Galileo had not been asked to defend himself before the Tribunal of the Inquisition, and the admonition that he received from Cardinal Bellarmine was given in private, and he could rely on the discretion of those who had communicated it. If the did not tell anyone, it would never be bruited. Galileo chose, wisely, to keep mum. On 6 March, he wrote to Curzio Picchena, the Tuscan Secretary of State, to say that he had not written the week before because nothing had happened. But one of the most important events in his life had taken place: he had been admonished by Cardinal Bellarmine to abandon Copernicanism! But this was a personal matter and Galileo prayed to heaven that it would stay so. Yet Romans could put two and two together: Galileo had been campaigning vigorously for Copernicanism, which had now been officially decried as false and contrary to Scripture. Even Monsignor Querengo joked about it in a letter to Cardinal d'Este: "Galileo's arguments have vanished into alchemical smoke, for the Holy Office has declared that to maintain this opinion is to dissent manifestly from the infallible dogmas of the Church. We now know that, instead of imagining that we are spinning in outer space, we are at rest at our proper pace, and do not have to fly off with the Earth like so many ants crawling around a balloon.".⁹

The puff of smoke, the ants, and the balloon are quite ingenious, but Querengo knew better than to speak of the immobility of the Earth as an infallible dogma. The decree that proscribed Copernicus and other works that taught heliocentrism did not involve the infallibility of the Church, the pope or anyone else. It was, in the eyes of those who prepared and approved it, a prudential decision to remove from public circulation works that might lead unwary readers to misunderstand the nature of science and the role of Scripture. The Counter Reformation did not encourage discussion or debates about doctrinal matters. The theological pendulum that the reformers had pushed too far in one direction was now made to swing to the other extreme, but even the most conservative cardinals would not have considered a decree of the Congregation of the Index as offering a definitive statement of the Catholic faith.

Before leaving Rome, Galileo was granted and audience by Pope Paul V on 11 March. The next day he proudly reported that he had been allowed to accompany the Pope for a stroll in the gardens for three-quarters of an hour, and that the Pope had assured him that he "could feel safe" as long as he was alive.¹⁰ Meanwhile rumours were flying all over Italy that he had been summoned to Rome and charged with heresy. On 20 April, Castelli wrote from Pisa to report that it was said that he had secretly abjured his errors before Cardinal Bellarmine. Three days later, his friend Giovanfrancesco Sagredo confirmed that the same gossip had rumbled through Venice.

Only one course was open to Galileo. He had to appeal to Cardinal Bellarmine himself. He was given a friendly reception, and the cardinal even provided him with a certificate that exonerated him completely. The document began, "We, Robert Cardinal Bellarmine, having heard that it is calumniously reported that Signor Galileo Galilei has in our hand abjured and has also been punished with salutary penance, and being requested to state the truth as to this, declare that the said Galileo has not abjured, either in our hand, or the hand of any other person here in Rome, or anywhere else so far as we know, any opinion or doctrine held by him. Neither has any salutary penance been imposed on him; but that only the declaration made by the Holy Father and published by the Sacred Congregation of the Index was notified to him, which says that the doctrine attributed to Copernicus that the Earth moves around the Sun and that the Sun is stationary at the centre of the world and does not move from east to west, is contrary to the Holy Scriptures, and therefore cannot be defended or held. In witness whereof we have written and subscribed the present document with our own hand this twenty-sixth day of May 1616".¹¹

With this certificate in his pocket, Galileo felt that he could continue to publicly consider heliocentrism as a convenient, albeit arbitrary, mathematical tool and, in the secret of his heart, hope that the decree might one day be revoked.

Fourth Trip (22 April 1624 - 16 June 1624)
ROMAN SUNSHINE

After his return to Florence, Galileo was not unhappy to be distracted from his woes by the sudden and unexpected appearance of three comets in 1618. When Orazio Grassi, a Jesuit professor at the Roman College, claimed that they were located between the Sun and the Moon, Galileo published a critical review in which he disagreed with the Jesuit that the comets were proof that real change occurs in the heavens. Rather, Galileo defended the old Aristotelian position that comets were just a case of refraction of sunlight bouncing off high-altitude vapours rising from the surface of the Earth. Anyone who failed to see this, he sneered, was not fit to do science, let alone teach it. Grassi vindicated his position in a book entitled, An Astronomical and Philosophical Balance, and he sent a copy to Galileo, who was not amused. He penned a witty and scathing rejoinder, The Assayer (meaning a finer balance), in which he not only took the Jesuit to task but ridiculed him. This was discourteous; worse still, it lost him the support of the Jesuits who had helped him in the past and might have been able to lend a hand in the future. But in the summer of 1623, when The Assayer was about to be sent to the printer, Galileo had no time for diplomacy. He had just been elated by the good news that Cardinal Maffeo Barberini, a fellow Florentine and a man who called himself his friend, had been elected Pope and taken with the name of Urban VIII.

Galileo had tutored the Pope's nephew, Francesco, who at the young age of 27 was created Cardinal by his uncle. Galileo would have liked to rush to Rome but he was in poor health during the latter half of 1623 and he did not set out before the spring of the following year, arriving in Rome on Easter Monday 1624. On the very next morning he was received by the Pope, who granted him six interviews during the seven weeks he spent in the Eternal City. Urban VIII promised a pension for Galileo's son, Vincenzio, and for his daughter, Sister Maria Celeste, who was a nun, he was given the assurance that her convent would be provided with a better chaplain. At the leave-taking audience, the Pope presented him with a painting (which Galileo describes as fine but without mentioning the subject matter), two medals, one of gold, the other of silver, and several Agnus Dei, as were called cakes of wax stamped with the figure of a lamb bearing a cross or a flag.

There is no indication that the motion of the Earth was so much as broached. All Galileo knew about Urban VIII's views was what a German Cardinal, Frederic Eutel von Hohenzollern (called also Zollern) told him. Zollern had told the Pope about the difficulties he had in converting German noblemen who had been shocked by the prohibition of Copernicus' book in 1616. The Pope had been sympathetic, and had replied that the Church had only condemned the doctrine of Copernicus as "rash," not as heretical. Nonetheless, he made it clear that, on his own view, there was no chance that it would ever be proved true, a position that he had expressed on other occasions, and that he was never to abandon.

Galileo also had conversations with Father Niccolo Riccardi, the influential Dominican who had licensed The Assayer, and Gaspar Schopp, a Lutheran who had converted to Catholicism. "They might not be as versed in astronomy as one might wish," Galileo wrote to his friend Cesi, "but they are nonetheless firmly of the opinion that this is not a matter of Faith and that Scripture should not be brought in. As far as truth or falsehood is concerned, Father Monster [as Riccardi was nicknamed because of his enormous girth] is neither for Ptolemy nor for Copernicus, but rests content with his own convenient way of having the heavenly bodies moved, without the slightest difficulty, by angels."¹²

Whether Father Monster really believed that angels have such kinetic power is open to doubt, but he was clearly sceptical about the possibility of finding the physical cause of planetary motion. Like Urban VIII, he was happy to let astronomers play around with planetary models, even if they rushed where angels fear to thread. The Sun-centred universe was an unproven idea without any prospect of confirmation in the future. The Pope and almost all his consultants believed that we can devise mathematical games about the cosmos, but we can never know what the building blocks really are.

The Pope's position was neither new nor outlandish, and it could be found in the preface that Andreas Osiander had added to Copernicus's De Revolutionibus Orbium Caelestium. Astronomical hypotheses are calculating devices; they have nothing to do with questions of truth or falsity. Urban VIII added a theological consideration: God is all-powerful and can create in a variety of ways what we know to be possible in one way only, for what is beyond our senses is beyond our ken. We look up to heaven to pray; the rest is mere speculation.

Galileo left Rome with an ornate Latin letter of Urban VIII to the Granduke, in which he is called "my beloved son who has entered the aetherial spaces, cast light on unknown stars, and plunged into the inner recesses of the planets".¹³ The text goes on in this way for several lines and, lest we attach too much importance to its glowing prose, it must be added that it was neither written nor signed by the Pope but by Giovanni Ciampoli, the secretary for official correspondence, and Galileo's friend of long standing.

But all was not to be plain sailing. Several months earlier, the Assayer had been denounced to the Holy Office. Historians had generally assumed that this was because Galileo spoke favourably of the Copernican theory, but since the discovery, in 1981, of an anonymous document in the archives of the Holy Office, we know that Galileo was accused of something very different and much more serious, namely endangering the Catholic doctrine of the Eucharist. By endorsing the atomic theory of matter Galileo had rendered himself suspect of denying the concept of transubstantiation.

To understand the background to this charge, we have to recall that Catholic thought was dominated since 1564 (the year of Galileo's birth) by the Decrees of the Council of Trent (1545-1563), which were promulgated that year. The Protestant Reformers had tended to emphasize the spiritual, and downplay the literal, meaning of Christ's words at the Last Supper, "This is my body; This is my blood." The Catholic bishops present at Trent stressed that these words meant that Christ was really present. They did not intend to explain away the mystery of the Eucharist but to offer an interpretation of the presence of Christ that was not merely symbolic, and this was conveyed by saying that the substance of the bread and wine became the substance of the body and blood of Christ (what they termed "transubstantiation"). What is left of the bread and wine after the consecration are only their appearances, such as their colour, taste, odour, and so on.

A philosophical school to which Galileo was close believed that matter is made up of invisible particles or atoms. On this view, "primary qualities," namely size, shape, and motion are really in the things themselves, whereas "secondary qualities," such as colours, tastes, and sounds, are not in the objects but in the organs that are stimulated by the "primary qualities" and, in this sense, they are subjective. In the Assayer, Galileo had given an atomistic interpretation of the nature of heat, which he described as caused by matter in motion. This clashed with the common-sense belief that heat is an intrinsic property of bodies.

Now the theological problem arises as follows: if colour, taste, and other "secondary qualities" are pronounced subjective, might this not imperil the teaching of the Council of Trent on the objective distinction between the real substance of Christ's body and blood and the equally real properties of bread and wine? A sensitive soul, or perhaps a malevolent colleague, had written to the Holy Office to draw attention to this latent danger. Fortunately for Galileo, Cardinal Francesco Barberini, who was a member of the Holy Office, offered to investigate the matter. He entrusted the task to his personal theologian, Giovanni di Guevara, who read Galileo's work and saw no reason to pursue the matter. So things calmed down, but it was only the lull before the storm.

Galileo had returned to Florence in the summer of 1624 with the conviction that he was now free to write his Dialogue on the Two Chief World Systems on the motion of the Earth as long as he avoided stating that it was physically true. The work is presented as the record of a discussion spread over four days, like a play in four acts, among three friends who meet in a palace in Venice. Galileo, who was now over sixty, welcomed the opportunity to bring back to life two of his best friends. The first is the Florentine Filippo Salviati, who speaks on Galileo's behalf and makes a brilliant case for Copernicanism. The second is the Venetian patrician Giovanfrancesco Sagredo, in whose palace the meeting is held. He is presented as open-minded and unprejudiced, but he is already converted to Copernicanism and plays second fiddle to Salviati. The third participant, an Aristotelian professor called Simplicio, is a fictional character, but Simplicius was the name of a sixth-century Greek philosopher who was famous for a commentary on Aristotle. In Italian, Simplicio also sounds like simpleton, and Galileo may have intended the pun.

Fifth Trip (3 May 1630 - 26 June 1630)
STAR-CROSSED HEAVENS

Galileo had hoped that his book, like his previous one, would be published in Rome at the expense of Prince Cesi, and in 1630 he decided to go once more to Rome to discuss practical matters and have a word with the censors. Galileo was travelling in an official capacity, but things had been arranged pretty much at the last moment, and the Florentine ambassador, Francesco Niccolini, was surprised to see him arrive in Rome, unannounced and unexpected, on the evening of Friday, 3 May. He nonetheless made him welcome and with his wife, Caterina Riccardi, a cousin of the Master of the Sacred Palace, saw to his comfort and welfare.

Galileo does not seem to have kept a dose eye on politics, but he could not have failed to notice that things had changed in Rome since 1624, when he had been able to see the new pope, Urban VIII, six times in seven weeks. This was no longer possible in the tense political climate of 1630. The Thirty Years' War, which had begun as a clash between German Catholic and Protestant princes had spiralled out of control to involve many other countries including Italy, France, Spain, Portugal, Sweden, Denmark, Poland, Transylvania, and Turkey. By 1630, only a few of the various causes that fuelled the conflict still pertained to genuinely religious issues. Particularly worrisome was the struggle between the Catholic monarchs of France and Spain for control of the Holy Roman Empire. As the leader of Christendom, the pope might have been expected to try to reconcile the French Bourbons and the Spanish Habsburgs, but his overt sympathy for King Louis XIII and Cardinal Richelieu irked the Spanish cardinals, who began to denounce his policy. In return Urban VIII grew suspicious of officials who had close ties with Spanish prelates. Unfortunately for Galileo, Ciampoli was eventually found to be a part of this group.

These worries made the pontiff so restless that he ordered all the birds in his garden killed because they disrupted his sleep with their nocturnal calls. The Pope had become enmeshed in the war of the Mantuan Succession, in which French and Spanish interests were again at stake. To cover the high cost of equipping 7,000 infantrymen and 800 cavalry, Urban VIII had to raise taxes in the Pontifical States, thereby undermining his popularity. The war of the Mantuan Succession had an even more unfortunate consequence: The Austrian Habsburg troops that crossed the Alps left the plague in their wake in 1629, and the disease spread like wildfire.

Discontent with the Pope's external policy was fuelled by resentment against the promotions and pensions that he showered on members of his family. Nepotism was a way of insuring that higher officials remained loyal, but it was often used to accumulate wealth at the expense of more worthy causes. Shortly after his election in 1623, Urban VIII had made his brother, Antonio and a nephew, Francesco, cardinals. In 1628, he added his youngest nephew, also called Antonio, who was barely 19. Meanwhile, he had chosen the middle child among his three nephews, Taddeo, to perpetuate the Barberini name and had married him to the daughter of a titled Roman family.

Urban VIII had always been proud of his gifts as a versifier, and he was only too ready to accept the adulation of courtiers who called him the greatest poet of his age. When he reformed the breviary, the handbook of prayers to be recited each day by persons in holy orders, he did not hesitate to add his own original hymnal compositions in honour of the saints that he canonized. He even undertook a lasting memorial to his name in the basilica of St. Peter by ordering the great architect Gian Lorenzo Bernini to erect a monumental canopy or baldacchino over the tomb of the first of the apostles. When Galileo returned to Rome in 1630 the huge bronze baldacchino was rising from four marble plinths, each emblazoned on two sides with the Barberini three-bee coat of arms. Four support pillars spiralled upward 29 metres toward the canopy, which was still under construction. The enormous quantity of bronze required for this gigantic structure had been plundered from the Pantheon, which even the barbarians had left intact. The punning gibe, "What the barbarians did not do, the Barberinis did," was soon in the mouth of every Roman. The growing dissatisfaction with the Barberinis found expression in a way that was characteristic of the age: astrological forecasts prophesying the early demise of the pontiff began to appear, and Galileo's name was to be associated with these ill-advised horoscopes.

When Galileo arrived in Rome Urban VIII was staying at Castel Gandolfo, some thirty kilometres away, in an old castle that he had restored and turned into his country residence. But no sooner had he returned to Rome around mid-May than he granted Galileo an audience. This was to be their only meeting during the eight weeks Galileo spent in Rome. His Holiness, as we have seen, had to attend to more pressing matters than guesswork about the nature of the rising and the setting of the Sun. Galileo was probably received by the Pontiff on 18 May, the very day the gossip column known as the Avvisi spread the following item of news: "Galileo, the famous mathematician and astronomer, is here to try to publish a book in which he attacks several opinions held by the Jesuits. He has been understood to say that D. Anna. [Colonna, the wife of Taddeo Barberini, the Pope's nephew] will give birth to a son, that we shall have peace in Italy at the end of June, and that shortly thereafter Taddeo and the Pope will die".¹⁴

The rumour that Galileo had something to do with the newssheets retailing prophesies of the early death of the Pope was pure libel. As a professional astronomer, Galileo occasionally cast horoscopes, and a disreputable journalist could seize on that to write a sensational article that rested on no other evidence than the fact that life-threatening forecasts concerning the Barberini had begun to appear. Alas, some of Galileo's friends may have been involved in these dubious exercises in astrological computation.

We do not know what Galileo said to Urban VIII when they met, but the Pope did most of the talking during audiences and it was not always easy to get in a word. How much Galileo was allowed to say will remain a mystery, but the Pope's position had not changed. Galileo had heard it from his own lips as early as 1616, and what the Pontiff had said was recorded by Agostino Oregio, his personal theologian, in a book published in 1629. While still a cardinal, wrote Oregio, Urban VIII had told a "learned friend" of his, who had worked out the path of the planets on the assumption that the Earth moves, that many other models were conceivable, for God can do anything that is logically possible.

There can be little doubt that the "learned friend" was Galileo, for the Pope's argument is echoed at the end of the Dialogue. Unfortunately, it is placed in the mouth of Simplicio, who did not distinguish himself by his intelligence during that time. Simplicio is made to say that he considers Galileo's arguments for the motion of the Earth ingenious but not conclusive because of what he heard "from a most eminent and learned person, before which we must fall silent." To which, Galileo's mouthpiece, Salviati, replies: "What an admirable and angelic doctrine! It is in agreement with another one, equally divine, which allows us to argue about the constitution of the universe (perhaps in order that the working of the human mind should not be curtailed or become lazy) while making it clear that we cannot discover the work of His hands. Let us, then, exercise the activities permitted to us and ordained by God, that we may recognise and thereby so much the more we admire His greatness, however much less fit we may find ourselves to penetrate the profound depths of His infinite wisdom."¹⁵

The claim that God can create things in a variety of ways is not ludicrous in itself, but it arrives after Salviati has shown that the evidence in favour of Copernicanism is overwhelming. For someone who had read the Dialogue from the beginning, the passage quoted above was unmistakably ironic, although taken in isolation and without awareness of what comes before, it might pass muster. Galileo was not foolish enough to enjoy a cheap joke at the pope's expense, but he may have been vain enough to think that neither he nor his censors would notice. In this, he was sadly mistaken. When the book finally appeared in print in 1632, someone murmured in the pontiff's ear that he was being ridiculed.

Sixth Trip (13 February 1633 - 6 July 1633)
FOUL WEATHER IN ROME

On Sunday, February 22, 1632, the Grand Duke of Tuscany was given a copy of the Dialogue in a ceremony at his Palace. The first sign of trouble came in July 1632 when Urban VIII had the Dialogue removed from bookshops. On 4 September 1632 Ambassador Niccolini had a stormy audience with the Pope, who broke out "in an outburst of rage" against Galileo. Niccolini tried, as he had been instructed by the Granduke, to obtain that Galileo be notified of the charges against him. The Pope answered that the Holy Office was not an ordinary court of law. It studied the case, and if the accused was found guilty he was told to recant. When Niccolini urged his request, Urban replied impatiently: "This kind of information is never given out in advance to anyone. Such is not the procedure. Besides, he knows very well where the difficulties lie if he wants to, since I discussed them with him, and he heard them from myself."¹⁶ Niccolini now tried another tack: Since the Dialogue was officially dedicated to the Granduke of Tuscany by someone who worked for him, might it not be wise to use clemency and hush the matter up? For all reply the Pope said that he had banned works dedicated to himself and that even had his name on the cover.

Galileo's file in the archives of the Holy Office was re-opened and the admonition that he had received in 1616 from Cardinal Bellarmine was found. It was now clear that Galileo had been told to abandon the Copernican theory. The news of the injunction struck Florence like a bombshell. The Granduke and his advisers were shocked. The scales tipped; far from being the victim of unscrupulous adversaries, Galileo suddenly became the man who acted under a cloak of secrecy. The Granduke immediately took a more cautious stance in dealing with Rome. In fair return, the Pope treated Galileo with a leniency that was rare in the seventeenth century. When he was summoned to Rome in 1633, he was lodged at the Tuscan embassy and not placed under arrest in the Holy Offìce, as would normally be done. The few days that he spent inside the Vatican during his trial were not spent in a prison cell but in the comfortable apartment that the notary had vacated for him. He was not served the usual food but meals prepared by the chef at the Tuscan embassy. After his condemnation, he was not incarcerated but placed under house arrest, first at the Villa Medici, then at the palace of Archbishop Piccolomini in Siena, and finally in his own house in Florence.

Galileo was summoned to Rome on 1 October 1632, but he tried to drag things out. On 13 October, Galileo wrote to Cardinal Francesco Barberini a letter in which he pleaded for mercy on the grounds of his advanced age (he was 68 but said he was 70). He claimed that the poor state of his health, the inclemency of the roads, and the bad weather would not allow him to make it halfway to Rome. Instead he offered to respond to objections in writing or to appear before the Florentine inquisitor. The archbishop, or anyone they should choose to appoint. But the Pope would brook no further delay, and Galileo had to leave for Rome on 20 January 1633. His carriage was halted on the border and the Papal States. The plague had flared up and quarantine had been imposed. It was only on the first Sunday of Lent, 13 February that he finally entered Rome. Two days later, on 15 February, he turned 69 without fanfare. The event is not even mentioned in the correspondence.

Galileo was made to wait until 12 April 1633 before being called to the Holy Office in the Vatican. As Urban VIII had made clear to Ambassador Niccolini, the Tribunal of the Inquisition was a court where defendants were summoned not to justify themselves but to acknowledge their errors and recant. Voluntary confession was not only wise but mandatory. Nonetheless, if being called before the Holy Office was an indication of guilt, the penalty was only decided after an interrogation had taken place.

We must not picture Galileo as being ushered into the presence of the Pope or the ten cardinal inquisitors. The interrogation was conducted by two officials: Commissioner Vincenzo Maculano and his assistant, Prosecutor Carlo Sinceri. The Commissioner asked about what Cardinal Bellarmine had told Galileo in 1616. Galileo, who already knew that a memorandum had been found in his file at the Holy Office, replied that Cardinal Bellarmine had informed him that the opinion of Copernicus could be held hypothetically, as Copernicus himself had done. When the Commissioner sought to probe further into what Cardinal Bellarmine had said, Galileo thought the moment had come to produce his secret weapon, and he drew out a copy of the certificate that Bellarmine had given him, adding that he had the original in Bellarmine's own handwriting. Galileo's triumph was shortly lived, however, for the Commissioner continued asking him whether he had been given a clear order not to hold, defend, or teach Copernicanism in any way whatsoever, as stated in the memorandum. Galileo answered that he only remembered Bellarmine's handwritten words. If something else was told him, he added, "I did not give much thought to it or keep it in mind because I was given some months later the certificate of Cardinal Bellarmine of 26 May that I have presented, and in which it is mentioned that I was ordered not to hold or defend the said opinion. As for the other two particulars of the precept now notified to me, that is 'nor teach' and 'in any way', I do not remember them, I think because they are not set forth in the certificate on which I relied and kept as a reminder."¹⁷

The Commissioner then enquired whether, "after the aforesaid injunction was issued," Galileo had asked for permission to write in favour of the motion of the Earth. Galileo answered that he did not consider this necessary because he had not contravened Bellarmine's orders. The Commissioner listened patiently before asking whether he had told Father Riccardi about the injunction that he had received. Galileo had not expected this direct question and his reply, the last at the end of the long interrogation, was to determine the evolution of the trial: "I did not happen to discuss that command with the Master of the Sacred Palace when I asked for the imprimatur, for I did not think it necessary to say anything because I had no doubts about it since I neither maintained nor defended in that book the opinion that the Earth moves and the Sun is stationary. Rather I proved the contrary and showed how weak and inconclusive the arguments of Copernicus were."¹⁸

By claiming that he had not argued in favour of Copernicanism, Galileo had painted himself into a corner from which he would be unable to extricate himself. The Holy Office knew full well that the Dialogue on the Two Chief World Systems had been written to demonstrate that the Earth goes around the Sun, something only a silly person, like Simplicius, could fail to see. The tribunal would not take kindly to the suggestion that they were simpletons.

After his interrogation on 12 April, Galileo was assigned to a suite of three rooms in the palace of the Inquisition. He wrote to Florence to say how spacious they were and how graciously he was being treated. His daughter, Maria Celeste, could read between the lines, and she knew that her father was in great distress. As the days dragged on, it became clearer to Commissioner Maculano that things would go very badly for Galileo if he persisted in denying that his book was not a defence of Copernicanism. At a meeting of the Holy Office on 28 April 1633, Maculano suggested a course of action that was unusual: he proposed to have a heart-to-heart conversation with Galileo and deal with the matter extrajudicially. Some of the cardinals immediately voiced their doubts about Galileo's willingness to be reasonable, but the Commissioner, who was eager to spare Galileo and the Church from more unpleasantness, convinced them to let him try. He met Galileo, and he agreed to co-operate. Once he had given in, the sequel was just a matter of following the routine and showing that due process had been observed. Three days after his interview with Maculano, Galileo re-entered the Commissioner's office for a second formal hearing on Saturday, 30 April. As we know from the transcript, Galileo declared that over the last few days he had thought it advisable to reread his Dialogue, which he had not looked at for the past three years. He wanted to see whether he had unwittingly given offence. "Not having seen it for so long," he explained, "it seemed almost a book by another author. I freely confess that it appeared to me in several places to be written in such a way that a reader, ignorant of my intention, would have reason to believe that the arguments for the wrong side, which I intended to confute, were so expressed that they meant to convince rather than be easily refuted."¹⁹

Galileo singled out his two prize arguments (the rotation of sunspots and the oscillating motion of the tides) as having been presented too energetically when they were no proof at all. He supposed, he said, that he had succumbed to the natural complacency that everyone feels for one's own ideas and had tried to show himself more skilful than others in devising, even in favour of false propositions, clever arguments. "My error," he confessed, "has been one of vainglorious ambition, pure ignorance and inadvertence."²⁰

On 10 May, Galileo returned to the Holy Office for the third time. The Commissioner officially informed that he had eight days to present his defence. But he had already written it, and produced it to Maculano. On Tuesday, 21 June, he was summoned for the fourth and last time. He maintained that he had never held the Copernican theory after its condemnation in 1616 and that he had not advocated it in the Dialogue. He was then formally commanded to tell the truth, "otherwise one would have recourse to torture," to which he replied, "I am here to obey, but I have not held this opinion after the determination was made, as I said."²¹ Galileo signed his declaration and left the room. We can almost hear his judges heaving a sigh of relief.

On the next day, Wednesday, 22 June, Galileo was ushered into a room adjoining the church of Santa Maria sopra Minerva, in what is now part of the library of the Italian parliament.This was to be the most unpleasant part of the trial. Galileo was ordered to kneel down while his sentence was read out. He was condemned for holding an opinion after it had been declared contrary to Scripture. The tribunal was ready to absolve him if he formally abjured his errors, but his book would be proscribed and he would be condemned to imprisonment. As a religious penance they imposed upon him the duty to recite the seven penitential psalms once a week for the next three years. This would have taken him about 20 minutes, but his daughter Maria Celeste relieved him of the burden after securing ecclesiastical permission to take it upon herself.

Of the ten cardinal inquisitors seven were present, the average number at meetings. The most conspicuous absence was that of Francesco Barberini, the Pope's nephew, who had always advocated clemency. The second absentee was Cardinal Gaspare Borgia, who had recently inveighed against the pope at a meeting of the cardinals and was probably unwilling to condemn anyone who caused embarrassment to Urban VIII. The third was Cardinal Laudivio Zacchia. No documents explaining these absences have survived, and the three cardinals may simply have been ill or bound by other duties on that day.

In popular accounts it is sometimes said that when Galileo rose from his feet he muttered under his breath, "Eppur si muove" (And yet it moves). This may have been his inner conviction, bur he was wise enough not to express it before his judges. His confession had been part of a deal and the next day, 23 June, his imprisonment was commuted to house arrest in the Villa Medici. Soon thereafter the ambassador requested that Galileo be allowed to leave Rome for Siena, where his friend Ascanio Piccolomini was Archbishop. This was granted at a meeting of the Holy Office presided by the Pope on 30 June.

In Siena, Galileo was not treated as a self-confessed heretic but as a good Catholic and an honoured guest. Archbishop Piccolomini invited scholars to dine with them and he provided Galileo with the opportunity for lively conversations. Tongues began to wag and someone sent an anonymous letter to the Holy Office in which he claimed that Galileo was spreading unorthodox ideas in Siena with the approval of the Archbishop, who was rumoured to have told several people that Galileo had been unjustly sentenced by the Holy Office.

In December 1633 Galileo was authorised to return to his villa in Arcetri, but his movements were restricted. He was free to receive members of his family or friends, but under no circumstances was he to hold meetings or entertain a large number of people. He was not allowed to go down to Florence, but could visit his daughters in the neighbouring convent. Galileo's eyesight began to deteriorate rapidly in 1637 and blindness was soon added to his miseries. In 1638 he obtained permission to stay in Florence at the house of his son but was still kept under house arrest to the point that he needed a special permission to attend, at Easter, the Church of St. Giorgio a few yards away. In 1639 he was back at Arcetri, where a young scientist, Vincenzio Viviani, came to live with him. Toward the last, Evangelista Torricelli was to join him as amanuensis and companion.

Galileo became gravely ill in the autumn of 1641, and after two months of suffering died on the evening of 8 January 1642. His body was brought from Arcetri to the church of Santa Croce in Florence, and preparations were made for a public funeral, but the Pope intervened and objected, and Galileo was not buried in the nave of the church, where his body now rests, before 1737. One cannot help feeling that relations between science and religion would have been different if Urban VIII had been more lenient. But then history cannot be rewritten. All we can do is try to learn from it.

Notes

(1) A more extended version of this text will be found in William R. Shea and Mariano Artigas, Galileo in Rome: The Rise and Fall of a Troublesome Genius (New York: Oxford University Press, 2003).

(2) Galileo Galilei to Filippo Salviati, 22 April 1604, in: Galileo Galilei, Opere, National Edition by Antonio Favaro (Florence: G. Barbèra, 1890-1909), vol. 11, p. 89.

(3) F rancesco Maria del Monte to Cosimo II, 31 May 1611: ibid., vol. 11, p. 119.

(4) Benedetto Castelli to Galileo Galilei, 14 December 1613: ibid., vol. 11, pp. 605-606.

(5) Galileo Galilei, Letter to Christina of Lorraine: ibid., vol. 5, p. 316.

(6) Robert Bellarmine to Paolo Antonio Foscarini, 12 April 1615: ibid., vol. 12, pp. 171-172.

(7) Antonio Querengo to Alessandro d'Este, 20 January 1616: ibid., vol. 12, pp. 226-227.

(8) Censure of the Holy Office, 19 and 25 February 1616: ibid., vol. 19, pp. 320-321.

(9) Antonio Querengo to Alessandro d'Este, 5 March 1616: ibid., vol. 12, p. 243.

(10) Galilleo Galilei to Curzio Picchena, 12 March 1616: ibid., vol. 12, p. 248.

(11) Certificate by Robert Bellarmine, 26 May 1616: ibid., vol. 19, p. 348.

(12) Galileo Galilei to Federico Cesi , 8 June 1624: ibid., vol. 13, p. 183.

(13) Urban VIII to Granduke Ferdinand II: ibid., vol. 13, p. 184.

(14) Avvisi di Roma (a kind of early newspaper): ibid., vol. 14, p. 103.

(15) Galileo Galilei, Dialogue on the Two Chief World Systems, Fourth Day: ibid., vol. 7, p. 489.

(16) Francesco Niccolini to Andrea Cioli, 5 September 1632: ibid., vol. 14, pp. 383-384.

(17) Galileo's First Deposition, 12 April 1633: ibid., vol. 19, p. 340.

(18) Galileo's First Deposition, 12 April 1633: ibid., vol. 19, p. 341.

(19) Galileo's Second Deposition, 30 April 1633: ibid., vol. 19, p. 343.

(20) Ibid.

(21) Galileo's Fourth Deposition, 21 June 1633: ibid. vol. 19, p. 362.