Galileo's Daughter

by Dava Sobel

  Several other people showed up unexpectedly at the cardinal’s house to see Galileo, led by Father Michelangelo Seghizzi, the Dominican commissary general of the Holy Office of the Inquisition, who had been one of the eleven voting theologians on the recent panel. He also claimed to speak for the pope, telling Galileo to relinquish the opinion of Copernicus or else the Holy Office would proceed against him. Again Galileo acquiesced.

  The following week, on March 5, the Congregation of the Index published a proclamation that expounded the official position on Copernican astronomy—namely, that it was “false and contrary to Holy Scripture.” The decree also named names and called for action. It suspended Copernicus’s book until corrections were made in it, “so that this opinion may not spread any further to the prejudice of Catholic truth.” It also cited another book, by the Carmelite father Paolo Antonio Foscarini, who had enthusiastically supported Copernicus by quoting chapter and verse from both De revolutionibus and the Bible, to show how the two texts could be reconciled. Foscarini fared far worse than Copernicus in the decree, because his book was condemned outright—prohibited and destroyed. Nor did the dismal aftermath end there. The printer in Naples who had published Foscarini’s book was arrested soon after the March edict, and Father Foscarini died suddenly in early June, at the age of thirty-six.

  Given the specificity of the edict, Galileo saw clearly that only the book attempting to square Copernicus with the Bible had been singled out for the harshest treatment. The two other books cited —that of Copernicus himself and another called On Job by Diego de Zuniga —were merely suspended pending certain deletions and corrections. Galileo’s own book, the Sunspot Letters, which was also circulating at the time, escaped any mention in the edict, though it strongly supported Copernican astronomy. While Galileo had delved deeply into the Bible and its interpretation with his Letter to Grand Duchess Cristina, this work had not yet been published; his “Treatise on the Tides” likewise existed in manuscript only.

  Pope Paul V

  Having been omitted from the text of the edict, and having escaped any personal censure, Galileo brightened. True, the theory he defended had been condemned, but he emerged free to consider it hypothetically, and to nurture the hope that the decree might one day be repealed. He remained the preeminent figure in Italian science, as well as the representative of the Florentine House of Medici. Galileo stayed on in Rome another three months, during which time he met again with Cardinal Bellarmino and spent nearly an hour in a private audience with Pope Paul on March 11.

  “I told His Holiness the reason for my coming to Rome,” Galileo wrote home to the Tuscan secretary of state,

  and made known to him the malice of my persecutors and some of their calumnies against me. He answered that he was well aware of my uprightness and sincerity of mind, and when I gave evidence of being still somewhat anxious about the future, owing to my fear of being pursued with implacable hate by my enemies, he consoled me and said that I might put away all care, because I was held in so much esteem both by himself and by the whole congregation of cardinals that they would not lightly lend their ears to calumnious reports. During his lifetime, he continued, I might feel quite secure, and before I took my departure he assured me several times that he bore me the greatest good will and was ready to show his affection and favor towards me on all occasions.

  In the wake of the edict against Copernicus, gossip of heresy and blasphemy continued to smear Galileo’s name, though he had not been tried or convicted of any crime. In Venice, word spread that Galileo had been summoned to Rome to account for his beliefs and had now been called to account in the strictest sense. Gossip rumbled through Pisa of how Cardinal Bellarmino had forced Galileo to renounce his beliefs and repent. At the end of May, just before Galileo returned to Florence, he appealed to the cardinal for redress and received this vindicating letter of endorsement:

  We, Roberto Cardinal Bellarmino, 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 Signor Galilei 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 Fathers and published by the Sacred Congregation of the Index has been notified to him, wherein it is set forth that the doctrine attributed to Copernicus, that the Earth moves around the Sun and that the Sun is stationary in the center 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 these presents with our own hand this 26th day of May 1616.

  Silenced but exonerated, Galileo confined himself for the next several years to the safe application of his great discoveries, such as using the moons of Jupiter to solve the problem of finding longitude at sea—especially as success might win him the lucrative prize offered by the king of Spain—and studying the companion bodies of Saturn to try to determine their true size and shape.

  On October 4, the feast day of Saint Francis of Assisi, Galileo heard his elder daughter profess her vows at the Convent of San Matteo in Arcetri, about a mile from Florence, where she had already lived for three years. It is possible that when Galileo first arranged for his girls’ entry into the convent, he had only their immediate future in mind, and not a lifetime plan. Nevertheless, no husbands had been found.

  The form of life of the Order of the Poor Sisters which the blessed Francis founded is this: to observe the holy Gospel of our Lord Jesus Christ, by living in obedience, without anything of one’s own, and in chastity, [RULE OF SAINT CLARE, chapter 7]

  At the ceremony of her investiture Virginia relinquished her given name to be known henceforward as Suor Maria Celeste— the name God had chosen for her and whispered in her heart.

  From then on, it shall not be permitted her to go outside the monastery, [RULE OF SAINT CLARE, chapter II]

  The next autumn, on October 28, 1617, Livia followed her sister to become Suor Arcangela. Both girls would spend the rest of their lives at San Matteo.

  He Himself deigned and willed to be placed in a sepulchre of stone. And it pleased Him to be so entombed for forty hours. So, my dear Sisters, you follow Him. For after obedience, poverty, and pure chastity, you have holy enclosure to hold on to, enclosure in which you can live for forty years either more or less, and in which you will die. You are, therefore, already now in your sepulchre of stone, that is, your vowed enclosure, [TESTAMENT OF SAINT COLETTE]

  In a desultory manner, Galileo continued to share his abortive theory on the tides with friends in Italy and abroad. “I send you a treatise on the causes of the tides,” Galileo replied in 1618 to a request from Austrian archduke Leopold for a sample of his work, “which I wrote at the time when the theologians were thinking of prohibiting Copernicus’s book and the doctrine enounced therein, which I then held to be true, until it pleased those gentlemen to prohibit the work and to declare the opinion to be false and contrary to Scripture. Now, knowing as I do that it behooves us to obey the decisions of the authorities and to believe them, since they are guided by a higher insight than any to which my humble mind can of itself attain, I consider this treatise which I send you to be merely a poetical conceit, or a dream . . . this fancy of mine . . . this chimera.”

  [VIII]

  Conjecture

  here among shadous

  Galileo’s collected correspondence brims with allusions to illnesses that often kept him from replying sooner to someone or forced him to close a letter in haste. Changes in the weather “molested” him, his first biographer noted, and he typically fell sick in spring or fall, or both, about every other year throughout his adult life. Although Galileo rarely elaborated on the nature of these health crises, he may have suffered from some form of relapsing fever contracted during the
cave incident in Padua. Or he may have been a victim of malaria or typhoid, a common enough plight in Italy during that period. Another possible explanation for his pattern of repetitive malaise is an unspecified rheumatic disease, possibly gout, which could have accounted for the “very severe pains and twinges” his biographer said he sustained “in various parts of his body.” Gout also causes painful kidney stones (when the excess uric acid in the blood, typical of this disease, gets deposited as crystals in the kidneys as well as in the joint spaces), and Galileo complained more than once of prolonged kidney trouble. The quantities of red wine he produced and drank would only have exacerbated the condition (by raising his uric acid level). Even at a time when wine was generally considered the safer alternative to water, doctors recognized the causal connection between alcohol and attacks of gout. Galileo’s daughter, who made many of his pills and tonics in the convent apothecary shop, frequently counseled him in her letters to limit “the drinking that is so hurtful to you” because of the “great risk of getting sick.”

  Other symptoms Galileo sometimes singled out for specific mention included chest pain, a hernia for which he wore a heavy iron truss, insomnia, and various problems with his eyes— particularly unfortunate for an astronomical observer. “As a result of a certain affliction I began to see a luminous halo more than two feet in diameter around the flame of a candle,” Galileo wrote of one such condition to a colleague, “capable of concealing from me all objects which lay behind it. As my malady diminished, so did the size and density of this halo, though more of it has remained with me than is seen by perfect eyes.” His frequent telescope demonstrations may have predisposed him also to ocular infections, easily communicated by sharing an eyepiece.

  After Galileo moved to Florence in 1610, poor health and long periods of recuperation frequently drove him out of the city into the surrounding hills. “I shall have to become an inhabitant of the mountains,” Galileo vowed while he and his mother and the two little girls still resided on a city street, “otherwise I shall soon dwell among the graves.”

  For several ensuing years he relied gratefully on the hospitality of his friend and follower Filippo Salviati, who rescued Galileo from the foul city air. At Salviati’s Villa delle Selve in the hills of Signa, fifteen miles west of Florence, Galileo spent enough time to write the better part of two books—Bodies in Water and Sunspot Letters—while convalescing from his typical ills. When his ready access to this retreat ended in 1614 with Salviati’s death, Galileo pressed the search for his own year-round haven.

  In April of 1617, he took a fine villa atop the hill called Bellosguardo (beautiful sight) on the south side of the River Arno, offsetting the high annual rent of one hundred scudi by selling the grain and broad beans grown on the property. From his new aerie, Galileo enjoyed an unobstructed panorama of the heavens, with a downward vista that swept the russet roofs, domed churches, and city walls of Florence. To the east he could see the olive green hillside of Arcetri, where his daughters lived inside the walled Convent of San Matteo. It took him three-quarters of an hour on foot or by mule—when he was up to the trip—to visit them.

  Despite the salubrious atmosphere at Bellosguardo, however, another serious illness struck Galileo toward the end of 1617 and held him in its grip until spring came. In May 1618, thankful to be freed from his sickbed at last, he set out on a pilgrimage across the Apennine Mountains to the Adriatic coast, where he visited the “Casa Santa"—the House of the Virgin Mary in Loreto. This former residence of the Blessed Virgin, according to local legend, had abruptly uprooted itself from the Holy Land in the year 1294 and flown on the wings of angels to the laurel grove (loreto in Italian) that gave the present town its name. Galileo had first talked of worshiping at the popular shrine in 1616, after he escaped unscathed from the Copernican uproar in Rome, but events and maladies had kept him from fulfilling that intention until now, when he could also offer thanks for his recent recovery and pray for improved health in the future.

  He returned home in June to Bellosguardo and to his son, Vincenzio, whom he had brought from Padua in 1612 at the age of seven. By 1618, their male-dominated household also included two new students, Mario Guiducci and Niccolo Arrighetti, who, like Castelli before them and others to come after, would remain Galileo’s devoted friends for life. The thirtyish scholars busied themselves all that summer copying the master’s early theorems on motion, to help him return to the fundamental work he had forsaken in 1609 for the telescope. They mined the dense jumble of his Paduan notes and prepared neat sheets of paper, written extravagantly on one side only, for his review and revision.

  The three comets of 1618

  In September, just when Galileo’s student assistants had finished this preliminary work, another bout of illness prevented him from building on it as planned. The delay might have been merely temporary, except that while Galileo languished, the heavens sent him a new mystery to ponder, and this apparition initiated a cascade of events that postponed the publication of his motion studies for another two decades.

  A small comet glowed in the skies over Florence that September of 1618. Though unspectacular, as comets go, it was nevertheless the first comet to appear since the birth of the telescope. Other astronomers took to their rooftops with instruments of Galileo’s design, but Galileo himself remained indoors an invalid. Then another comet arrived in mid-November, while Galileo unfortunately fared no better than before. And even by the end of November, when a truly brilliant third comet burst on the scene to garner the attention of observers all over Europe, Galileo still could not stand among them.

  “During the entire time the comet was visible,” he reported later, “I was confined by illness to my bed. There I was often visited by friends. Discussions of the comets frequently occurred, during which I had occasion to voice some thoughts of mine which cast doubt upon the doctrines that have been previously held on this matter.” In fact, Galileo saw only one important comet his whole life—the big bright one of 1577, in his youth—and never did figure out what these objects really were.

  Most of Galileo’s contemporaries feared comets as evil omens. (Indeed the three 1618 examples were presently seen, with hindsight, as heralds of the Thirty Years’ War, which broke out in Bohemia the same year.) Aristotelian philosophers figured comets for atmospheric disturbances. The fact that comets came and went, changing their fuzzy-glow appearance all the while, automatically relegated them to the sublunar sphere between the Earth and the Moon, where they were thought to be ignited by friction of the sphere’s turning against the upper reaches of the air.

  It may seem incredible that Galileo resisted the temptation to go outdoors in the autumn of 1618 long enough to view any one of the three comets, especially since he felt well enough to enter into intellectual discussions with visitors. But in fact the November night air held terrible danger for him, a man well past fifty now, who had spent most of the current year battling one malady after another. Moreover, as Galileo no doubt knew from his friends’ accounts, he would not have seen much even if he had risked his own study of these objects. A comet, or “hairy star,” retained its blurred contours despite the aid of the most powerful telescope* Unlike the fixed stars that resolved into points of light when the telescope stripped them of their rays, or planets that turned to tiny globes, a comet could not be brought into sharp focus. And Galileo held back because he believed—in agreement for once with his Aristotelian contemporaries, though not for the same reasons—that comets belonged to the Earth’s atmosphere.

  Galileo thus rejected the findings of his Danish predecessor, Tycho Brahe, who had observed the great comet of 1577 and another in 1585. Tycho, probably the most able naked-eye stargazer who ever lived, followed that comet every night with his oversized measuring instruments to determine its position. It lay beyond the Moon, he discovered through position studies, perhaps as far as Venus, and that meant one of two things to his sixteenth-century way of thinking: Either the comet had come crashing through Aristo
tle’s crystalline celestial spheres, or the celestial spheres did not exist. Tycho chose the latter scenario, emboldened by having been the first European, in 1572, to identify a nova, which convinced him that changes could occur in the “immutable” heavens.

  Galileo, when he witnessed the next nova in 1604, backed the deceased Tycho’s interpretation of the new star’s nature and significance. But he despised Tycho’s planetary system for its poor compromise between Ptolemy and Copernicus. And as for the comet Tycho had tracked so carefully, Galileo dismissed it as a will-o’-the-wisp. He took comets to be anomalous illuminations in the air—most likely reflections of sunlight bounced off high-altitude vapors—not heavenly bodies per se. You could no more gauge the distance to a comet, Galileo believed, than you could catch a rainbow or contain the aurora borealis.

  None of the news, notes, or queries on the 1618 comets that reached Galileo shook him from his skeptical stance. Nor was he impressed by the pamphlet sent him from Rome containing a comet lecture delivered at the Collegio Romano and published in early 1619. Its author, Jesuit astronomer Father Orazio Grassi, argued on the basis of his studies that the path of the late-November comet carried it between the Sun and the Moon. This was a remarkable conclusion for any Jesuit to reach, because the Collegio Romano did not dispute Aristotle lightly. Nevertheless, Galileo doubted Father Grassi’s distance estimates, just as he had questioned Tycho’s, on the grounds that comets had no substance.