Galileo's Dream

Chapter four The Phases of Venus

Galileo woke lying on the ground next to his spyglass, the stool tipped over beside him. The night sky was lightening in the east, and Mazzoleni was tugging at his shoulder.

“Maestro, you should go to bed.”

“What?”

“You were in some kind of a trance. I came out before, but I couldn’t wake you.”

“I—I had a dream, I think.”

“It seemed more like a trance. One of your syncopes.”

“Maybe so.”

On the long list of Galileo’s mysterious maladies, one of the most mysterious was a tendency to fall insensible for intervals that ranged from minutes to three or four hours, his muscles rigid the entire time. His physician friend, the famous Fabrizio d’Acquapendente, had been unable to treat these syncopes, which in most people were accompanied by fits or racking seizures. Only a few sufferers like Galileo became simply paralyzed.

“I feel strange,” Galileo said now.

“You’re probably sore.”

“I had a dream, I think. I can’t quite remember. It was blue. I was talking with blue people. It was important somehow.”

“Maybe you spotted angels through your glass.”

“Maybe so.”

Galileo accepted the artisan’s hand, and hauled himself up. He surveyed the house, the workshop, the garden, all turning blue in the dawn light. It was like something. “Marc’Antonio,” he said, “do you think it’s possible that we could be doing something important?”

Mazzoleni looked doubtful. “Nobody else does what you do,” he admitted. “But of course it may just be that you’re crazy.”

“In my dream it was important.” Galileo stumped over to the couch under the portico and threw himself down on it, pulled a blanket over him. “I have to sleep.”

“Sure, maestro. Those syncopes must be real tiring.”

“Leave me instantly.”

“Sure.”

Mazzoleni left and he drifted off. When he woke again it was the cool of early morning, sunlight hitting the top of the garden wall. The morning glory was a well-named flower. The blue of the sky had pale sheets of red and white pulsing inside it.

The stranger’s old servant stood there before him, holding out a cup of coffee.

Galileo jerked back. On his face one could see the fear. “What are you doing here?” He began to remember the stranger’s appearance the night before, but little beyond that. There had been a big heavy spyglass that he had sat on his stool to look through…. “I thought you were part of the dream!”

“I brought you some coffee,” the ancient one said, looking down and to the side, as if to efface himself. “I heard you had a long night.”

“But who are you?”

The old man shoved the cup even closer to Galileo’s face. “I serve people.”

“You serve that man from Kepler! You came to me last night!”

The old one glanced up at him, lifted the cup again.

Galileo took it, slurped down hot coffee. “What happened?”

“I can’t say. You were struck by a syncope for an hour or two in the night.”

“But only after I looked through your master’s spyglass?”

“I can’t say.”

Galileo regarded him. “And your master, where is he?”

“I don’t know. He’s gone.”

“Will he return?”

“I can’t say. I think he will.”

“And you? Why are you here?”

“I can serve you. Your housekeeper will hire me, if you tell her to.”

Galileo observed him closely, thinking it over. Something strange had happened the night before, he knew that for sure. Possibly this old geezer could help him remember—or help him in whatever might come of it. Already it began to seem as if the ancient one had always been there.

“All right. I’ll tell her. What’s your name?”

“Cartophilus.”

“Lover of maps?”

“Yes.”

“And do you love maps?”

“No. Nor was I ever a shoemaker.”

Galileo frowned, then waved him away. “I’ll speak to her.”

And so I came into the service of Galileo, intending (as always, and always with the same failure) to efface myself as much as possible.

In the days that followed, Galileo slept in short snatches at dawn and after dinner, and every night stayed up to look through his spyglass at Jupiter and the little stars circling it, his curiosity now tweaked by an odd feeling in the pit of his stomach. He marked the four moons’ positions each night using the notation I, II, III, and IV, with I being the closest to Jupiter in the orbits he was now untangling, and IV the farthest away. Tracking and timing their movements gave him an increasingly confident sense of how long each took to circle Jupiter. All the expected signs of circular motion seen edge-on had manifested themselves. It was getting clearer what was going on up there.

Obviously he needed to publish these discoveries, to establish his precedence as discoverer. By now Mazzoleni and the artisans had made about a hundred spyglasses, but only ten of them were capable of seeing the new little planets; they became visible only through occhialini with magnifications of thirty times, and sometimes twenty-five when the grinding was lucky. (What else had been twenty-five or thirty times larger?) The difficulties in making a device this powerful reassured him; it was unlikely someone else would see the Jovian stars and publish the news before him. Still, it was best not to be slow about it. There was no time to lose.

“I’m going to make those bastard Venetians really regret their offer!” he declared happily. He was still furious at the senators for questioning his honesty in representing the spyglass as his invention. He took pride in his honesty, a virtue he wielded so vigorously as to make it a fault. He also hated their measly raise, which was not even to start until the new year, and now was looking more and more inadequate. And really, through all the years in Padua—eighteen now—he had kept in the back of his mind the possibility of a return to Florence.

Ignoring the little awkwardness that had developed the year before with Belisario Vinta, he wrote another florid note accompanying the finest spyglass he had, explaining that he was giving it to his most beloved student ever, now the grandissimo Grand Duke Cosimo. He described his new Jovian discoveries, and asked if it would be permissible to name his newly discovered little Jovian stars after Cosimo. And if so, if the grand duke would prefer him to name them the Cosmian Stars, which would merge Cosimo and Cosmic; or perhaps to apply to the four stars the names of Cosimo and his three brothers; or if they should together be named the Medicean Stars.

Vinta wrote back thanking him for the spyglass and informing him that the grand duke preferred the name Medicean Stars, as best honoring the family and the city it ruled.

“He accepted the dedication!” Galileo shouted to the household. This was a stupendous coup. Galileo hooted triumphantly as he charged around, rousing everyone and ordering that a fiasco of wine be opened to celebrate. He tossed a ceramic platter high in the air and enjoyed its shattering on the terrace, and the way it made the boys jump.

The best way to announce this dedication to the world was to insert it into the book he was finishing about all the discoveries he had made. He pressed hard to finish; the combination of work by both day and night left him irritable, but it had to be done. At night, working by himself, he felt enormously enlarged by all that lay ahead. Sometimes he had to take a break and walk around in the garden to deal with the thoughts crowding his head, the various great futures looming ahead of him like visions. It was only during the days when he flagged, slept at odd hours, snarled at the household and all that it represented. Scribbled at great speed on his pages.

He wrote the book in Latin so that it would be immediately comprehensible across all the courts and universities of Europe. In it, he described his astronomical findings in more or less chronological order, making it into a narrative of his discoveries. The longest and best passages were on the moon, which he also augmented with good etchings made from his drawings. The sections on the stars and the four moons of Jupiter were shorter, and mostly just announced his discoveries, which were startling enough not to need embellishment.

He told the story of his introduction to the idea of the occhialino or perspicillum with some circumspection:

About ten months ago, a rumor came to our ears that a spyglass had been made by a certain Dutchman, by means of which visible objects, although far removed from the eye of the observer, were distinctly seen, as though nearby. This caused me to apply myself totally to investigating the principles and figuring out the means by which I might arrive at the invention of a similar instrument, and I achieved that result shortly afterward on the basis of the science of refraction.

A few strategic opacities there, but that was all right. He arranged with a Venetian printer, Tomaso Baglioni, for an edition of 550 copies. The first page, an illustrated frontispiece, said in Latin:

The first four pages following this great proem of a title page were filled by a dedication to Cosimo Medici that was exceptionally florid even for Galileo. Jupiter had been in the ascendant at Cosimo’s birth, it pointed out; pouring out with all his splendor and grandeur into the most pure air, so that with its first breath Your tender little body and Your soul, already decorated by God with noble ornaments, could drink in this universal power…. Your incredible clemency and kindness … Most Serene Cosimo, Great Hero … when you have surpassed Your peers You will still contend with Yourself, which self and greatness You are daily surpassing, Most Merciful Prince … from Your Highness’s most loyal servant, Galileo Galilei.

The book was published in March of 1610. The first printing sold out within the month. Copies circulated throughout Europe. Indeed its fame was worldwide. Within five years word came that it was being discussed at the court of the Chinese emperor.

Despite this literary and scientific success, the Galilean household was still running at a loss, with Galileo’s time also massively overcommit-ted. He wrote to his friend Sagredo, I’m always at the service of this or that person. I have to eat up many hours of the day—often the best ones—in the service of others. I need a prince.

On May 7, 1610, he wrote a follow-up inquiry to Vinta. He did not beat around the bush, but made it an explicit letter of application, a real piece of rhetoric. He requested a salary of a thousand florins a year, and sufficient free time to bring to completion certain works he had in progress. Glancing up at the dusty workbooks on the shelf to make sure he forgot nothing, he made a list of what he hoped to publish if he were given the time:

Two books on the system and constitution of the universe, an overarching conception full of philosophy, astronomy, and geometry; three books on local motion, an entirely new science, as no one else ancient or modern has discovered the many amazing properties that I demonstrate to exist in natural and forced motions, which is why I may call this a new science discovered by me from its first principles; three books on mechanics, two pertaining to principles and foundations, one on its problems—and though others have written on this same material, what has been written to date is not one-quarter of what I will write, either in quantity or otherwise. I have also various little works on physical subjects, such as On Sound and Voice, On Vision and Colors, On the Tides, On the Composition of the Continuum, On the Motion of Animals, and still more. I will also write on military science, giving not only a model of what a soldier ought to be, but also mathematical treatises on fortification, the movement of troops, sieges, surveying, estimating distances and artillery power, and a fuller description of my military compass,

—which is in fact my greatest invention, he did not add—a single device that allows one to make all of the military calculations I have already mentioned plus also the division of lines, the solution of the Rule of Three, the equalization of money, the calculation of interest, proportional reduction of figures and solids, extraction of square and cube roots, identification of the mean proportionals, transformation of parallelepipeds into cubes, determination of proportional weights of metals and other substances, description of polygons and division of circumferences into equal parts, squaring of the circle or any other regular figures, taking the batter of scarps on walls—in short it was an omnicalculator, able to make any computation you could want, despite which hardly anyone has noticed its existence, and even fewer bought one, so stupid was the common run of humanity!

But that was not germane, even though the reaction to his compass still galled him and was one of the events driving this whole move back to Florence. It wasn’t a good subject to bring up, so he only moved to his conclusion:

Finally, as to the title and the scope of my duties, I wish in addition to the name of Mathematician that His Highness adjoin that of Philosopher. Whether I can and should have this title I shall be able to show Their Highnesses whenever it is their pleasure to give me a chance to deal with this in their presence with the most esteemed men of that profession,

—such as they are, being for the most part grossly overpaid Peripatetic idiots!

Reading over the final flourishes, and looking at the red leather of their best spyglass yet, embossed in gold with typical Florentine and Medici figures, it seemed to him that the opportunities being offered to any potential patron were too great to decline. What an application! Even the transport case into which everything was loaded for the Florentine courier was beautiful. Who could say no to such a thing?

And, in fact, on May 24, 1610, a reply from Vinta came to the house behind the church of Santa Giustina, the house on Via Vignali where they had all lived and worked together for eighteen years. Grand Duke Cosimo, Vinta wrote, accepts your services.

Galileo wrote to accept the acceptance on May 28. On June 5, Vinta wrote back, confirming that his title would be “Chief Mathematician of the University of Pisa and Philosopher to the Grand Duke.”

Galileo wrote back in turn, asking that his title be revised to “Mathematician and Philosopher to the Grand Duke.”

He also requested that he be absolved of any further obligation to his two brothers-in-law arising from defaults on dowry payments for his sisters. That would allow him to go home without the inconvenience of embarrassing lawsuits from those disgusting chiselers, or the possibility of arrest. He would go up to them in the streets and say to them, “I am mathematician and philosopher to the Grand Duke, go fuck yourselves.”

And all this was agreed to in his formal appointment of July 10, 1610. The new service to Cosimo was to begin in October. It was understood to be a lifetime appointment.

He had a Prince.

The move from Padua to Florence was complicated, and what had never been more than controlled chaos at Hostel Galileo fell into utter chaos. Among other more practical tasks, Galileo had to deal with a lot of hard feelings in Padua and Venice. Many of the Venetian pregadi were outraged to hear he was walking out on his acceptance of their recent offer, calling it gross ingratitude and worse. The procurator Antonio Priuli was particularly bitter. “I hope I never lay eyes on that ungrateful asshole again!” he was said to have shouted, and of course this was quickly reported to Galileo. And it wasn’t just Priuli; the anger was widespread. It was obvious Venice would never again offer him employment. He had cast his lot with Florence, and, people said grimly, it had better go well for him there, or else.

Galileo gritted his teeth and forged on with the chores of the move. This reaction was to be expected, it was just part of the price he had to pay to get patronage. It was a sign that the Venetians had valued him and yet taken advantage of him, and knew it and felt guilty about it, and as people would always rather feel angry than guilty, the transmutation of the one to the other had been easy. It had to be his fault.

He focused on practical matters. Merely boxing up the contents of the big house took weeks, and just at a time when his astronomical work was at a crucial point. Happily that was night work, so that no matter the loud and dusty tumble of days, he could always wake up after an evening meal and a nap, settle down on his stool, and make his observations through the long cool nights. This meant forgoing sleep, but as he had never been much of a sleeper anyway, often existing for months at a time on mere snatches, it did not really matter. And it was all too interesting to stop. “What must be done can be done,” he would say hoarsely to Mazzoleni as he flogged them through the afternoons. “We can sleep when we’re dead.” In the meantime, he slept whenever it was cloudy.

The household therefore avoided him in the morning, when he was often abusive, and even at the best of times a bit befuddled and melancholy. He would throw things at anyone foolish enough to bother him in the couple of hours it took to pull himself together, and out of what looked like deep sleep he could kick with vicious accuracy.

Once up, groaning and yawning on his bed, he broke his fast on leftovers, then took a walk in his garden. Pulled a few weeds, plucked a lemon or a cluster of grapes, then went back in to face the day: the move, the correspondence, the students, the accounts, the catering. A long dinner or supper usually included sugared ravioli, veal, great pies filled with pork, chicken, onions, garlic, dates, almonds, saffron and other spices, then also salads and pasta, all washed down with wine and ending with chocolate or cinnamon. At night, everyone else would collapse into bed while he went out to the terrazzo alone and made his observations, using spyglasses they had constructed back in the spring; there would be no more improvements made until he was settled in Florence.

But before that, of course, there was Marina to attend to. Ever since she had gotten pregnant, Galileo had provided her with the funds to rent and keep a little house on the Ponte Corvo, around the corner from his place, so that he could sometimes drop off the girls on the way to his lectures at Il Bo. Now Virginia was ten, Livia nine, and Vincenzio four. They had spent their whole lives between the two houses, although the girls were mostly in Galileo’s big place, being taken care of by the servants. Now decisions had to be made.

Galileo stumped down to the Ponte Corvo unhappily, readying himself for the inevitable tongue-lashing. He was a barrel of a man with a red beard and wild hair, but now he looked small. At moments like these, he could not help remembering his poor father. Vincenzio Galilei had been the most henpecked, pussy-whipped pancake of a husband in the history of mankind. He had felt the lash daily; Galileo had seen it with his own eyes. Marina was nothing compared to the old dragon, who was an educated woman and knew just where to stick the knives. Indeed, Giulia was even now a more fearful presence to Galileo than Marina, no matter Marina’s black gaze, her cobalt-edged tongue and thick right arm. He had heard so many harangues in his life he was an expert at them, a connoisseur, and there was no doubt the old rolling pin was champion of the world. His father’s hung head, the tightness at the corners of his mouth—the way he would pick up his lute and hit its strings, playing tunes double time and fortissimo, even though this only served as accompaniment to Giulia’s dread arias, which were louder by far than the lute—these scenes were all too clear in Galileo’s mind, if he did not avoid them.

And yet here he had gone and done the same thing as his dad. Probably it was a mistake to couple with a younger woman, as they both had; no doubt it led to some fundamental imbalance, or just the natural contempt of youth for age. In any case, here he was, another Galilei standing at the door about to get thrashed, hesitating to knock. Fearful to knock.

He knocked. She answered with a shout, knowing by the rap who it was.

He entered. She kept the place clean, there was no doubt of that. Perhaps she did it to emphasize the paucity of furniture, or the confusion and squalor of his place. In any case there she stood in the kitchen doorway wiping her hands, as beautiful as ever, even though the years had been hard on her. Black hair, black eyes, a face that still caught Galileo’s breath; the body he loved, her hand on her hip, washcloth flung over her shoulder.

“I heard,” she told him.

“I figured you would.”

“So—what now?”

She watched him, expecting nothing. It wasn’t like the time he had explained what their arrangement would be, sitting on the fondamenta in Venice with her five months pregnant. That had been hard. This was merely awkward and tedious. They hadn’t been in love for many years. She was seeing a man out near the docks on the canal—a butcher, he thought it was. He had what he wanted. Still, that look, that time in Venice—it shot through into this time too, it was still there between them. He had a particular sensitivity to looks, no doubt the result of growing up with Medusa for a mother.

“The girls will come with me,” he said. “Vincenzio is too young. He still needs you.”

“They all need me.”

“I’m taking the girls to Florence.”

“Livia won’t like it. She hates your place. It’s too loud for her, there are too many people.”

Galileo sighed. “It will be a bigger place. And I won’t be taking in students anymore.”

“So now you’re a court creature.”

“I am the prince’s philosopher.”

She laughed. “No more compasses.”

“That’s right.”

They both went silent, thinking perhaps about how his compass had been an ongoing joke between them.

“All right then,” she said. “We’ll be in touch.”

“Yes, of course. I’ll keep paying for this place. And I’ll need to see Vincenzio. In a few years he’ll move to Florence too. Maybe you can move to Florence then too, if you want.”

She stared at him. She could still flay him with a look. The tightness at the corners of her mouth reminded him of his father, and he felt a stab of remorse, thinking that maybe now he was the Giulia. A horrible thought—but there was nothing for it but to nod and take his leave, the back of his neck crawling under the heat of that fiery gaze.

All during this time he continued to make his nightly observations, and to spread the word concerning the usefulness of his glass. Occhialino, visorio, perspicillum—different people called it different things, and he did, too. He sent excellent glasses to the Duke of Bavaria, the Elector of Cologne, and Cardinal del Monte, among other nobles of court and church. He was now in the service of the Medici, of course, but the Medici would want the capabilities of his glass advertised to as many of the powers in Europe as possible. And it was important to establish the legitimacy of what Galileo had reported in his book by having it confirmed in other places by influential figures. He had heard there were people like Cremonini refusing to look through a glass, and others claiming his new discoveries were merely optical illusions, artifacts of the instrument itself. Indeed, he had suffered an unfortunate demonstration in Bologna, when he had tried to show the famous astronomer Giovanni Magini the Medicean Stars, and only been able to see one himself—which may have been because three were behind Jupiter, but it was a hard case to make, especially with the odious Bohemian climber Martin Horky there smirking at every word, obviously delighted that things weren’t going as planned. Afterward he heard that Horky had written to Kepler telling him that the visorio was a fraud, useless for astronomy.

Kepler was experienced enough to ignore backstabbing by such a loathsome toad, but his characteristically long and incoherent letter in support of Galileo’s discoveries, published as a book for the world to read under the title Dissertatio cum Nuncio Sidereo, was in some ways as bad as the Horky nonsense. Confusions from Kepler were nothing new—although up until this point they had always made Galileo laugh. One time for the sake of his artisans he had translated into Tuscan Kepler’s claim that the music of the spheres was a literal sound made by the planets, a six-note chord that moved from major to minor depending on whether Mars was at perihelia or aphelia. This idea made Galileo laugh so hard he could barely read. “The chapter’s title is ‘Which Planet Sings Soprano, Which Alto, Which Tenor, and Which Bass!’ I swear to God! The greatest astronomer of our time! He admits he has no basis for this stuff except his own desire for it, and then concludes that Jupiter and Saturn must sing bass, Mars tenor, Earth and Venus alto, and Mercury soprano.”

The workshop gang then sang, in their usual four-part harmony, one of their rudest love songs, replacing all the usual girls’ names with “Venus.”

That was Kepler: a good source for jokes. Now, reading Kepler’s defense of Galileo’s spyglass discoveries, Galileo felt an uneasiness that sharpened the further he read. Lots of people would read this book, but much of Kepler’s praise was so harebrained it cut both ways:

I may perhaps seem rash in accepting your claims so readily with no support from my own experience. But why should I not believe a most learned mathematician, whose very style attests to the soundness of his judgment? He has no intention of practicing deception in a bid for vulgar publicity, nor does he pretend to have seen what he has not seen. Because he loves the truth, he does not hesitate to oppose even the most familiar opinions, and to bear the jeers of the crowd with equanimity.

What jeers of the crowd? For one thing there hadn’t been that many, and for another, Galileo did not bear them with equanimity. He wanted to kill every critic he had. He liked fights in the same way bulls are attracted to red—not because it looks like blood, or so they say, but because it has the color of the pulsing parts of cows in heat. Galileo loved to fight like that. And so far he had never lost one. So equanimity had nothing to do with it.

Then further on in Kepler’s sloppy endorsement, he asked what Galileo saw through his perspicillum when he looked at “the left corner of the face of the Man in the Moon,” because it turned out that Kep ler had a theory about that region, which he now propounded to the world—that a mark there was the work of intelligent beings who lived on the moon, who must therefore have to endure days the equal of fourteen days on Earth. Therefore, Kepler wrote:

They feel insufferable heat. Perhaps they lack stone for erecting shelters against the sun. On the other hand, maybe they have a soil as sticky as clay. Their usual building plan, accordingly, is as follows. Digging up huge fields, they carry out the earth and heap it in a circle, perhaps for the purpose of drawing out the moisture down below. In this way, they may hide in the deep shade behind their excavated mounds and, in keeping with the sun’s motion, shift about inside, clinging to the shadow. They have, as it were, a sort of underground city. They make their homes in numerous caves hewn out of that circular embankment. They place their fields and pastures in the middle, to avoid being forced to go too far away from their farms in their flight from the sun.

Galileo’s jaw dropped as he read this. He was growing to dread the appearance of the word accordingly in Kepler’s work, a tic that always marked precisely the point where sequential logic was being tossed aside.

Then a few pages later, worse yet: Kepler spoke of the difference Galileo had noted through his spyglass between the light of the planets and that of the fixed stars: What other conclusion shall we draw from this difference, Galileo, than that the fixed stars generate their light from within, whereas the planets, being opaque, are illuminated from without; that is, to use Bruno’s terms, the former are suns, the latter, moons or earths?

Galileo groaned aloud. Just the sight of Bruno’s name in the same sentence as his own was enough to churn his stomach.

Then he came to a passage that made him go chill and hot at the same time. After Kepler’s congratulations for discovering the moons of Jupiter, and his ungrounded assertion that there must be a purpose for these new moons—and a false syllogism stating that, since the Earth’s moon existed for the pleasure of the people on Earth, the moons of Jupiter must exist to please the inhabitants of Jupiter, Kepler concluded that these inhabitants—

—must be very happy to behold this wonderfully varied display. The conclusion is quite clear. Our moon exists for us on the earth, not for the other globes. Those four little moons exist for Jupiter, not for us. Each planet in turn, together with its occupants, is served by its own satellites. From this line of reason we deduce with the highest degree of probability that Jupiter is inhabited.

Galileo threw this craziness to the floor with a curse and stalked out into his garden, wondering why his hilarity had so quickly turned to dread. “Kepler is some kind of idiot!” he shouted at Mazzoleni. “His reasoning is completely deranged! Inhabitants of Jupiter? Where the hell did that come from?”

And why was it so disturbing to read it?

The stranger … the man who had told him about the occhialino that afternoon in Venice … who had appeared after the great demonstration to the Venetian senate, and suggested he take a look at the moon—had he not said something about coming from Kepler? Quick flashes of something more—a blue like twilight—Had the stranger not come knocking at the gate one night some time ago? Had Cartophilus not joined the household soon after? What did all that mean?

Galileo was not used to having a vague memory of anything. Normally he would have said that he remembered basically everything that had ever happened to him, or that he had read or thought. That, in fact, he remembered too much, as quite a bit of what he recalled stuck in his brain like splinters of glass, stealing his sleep. He kept his thoughts busy partly in order not to be stuck by anything too sharp. But in this matter, clarity did not exist. There were blurs, as if he had been sick.

Cartophilus was picking up Kepler’s book from the floor of the arcade, dusting it off, looking at it curiously. He glanced at Galileo, who glared at him as if he could drag the truth from the old man by look alone. A nameless fear pierced Galileo: “What does this mean!” he shouted at the wizened old man, striding toward him as if to beat him. “What’s going on?”

Cartophilus shrugged furtively, almost sullenly, and put the book on a side table, closed so that the page Galileo had been reading was lost. Inhabitants of Jupiter!

“We have to keep working on the move to Florence, sire,” he said. “I’m supposed to be packing the pots.” And he left the arcade and went inside, as if Galileo were not his master and had not just asked a question of him.

Galileo’s return to Florence, as he was now calling his decision, continued to draw fire in Venice and Padua. Priuli was now terming it a breach of contract as well as a personal betrayal, suggesting to the Doge that it would be appropriate to ask for some salary to be returned.

With the mood turning so hard against him, it was a great comfort to know that Fra Paolo Sarpi would remain as steadfast a friend and supporter as he had always been. Galileo had referred to him as “father and master” in his letters to him for many years. Having Sarpi on his side was important.

One day, Sarpi was passing through Padua and dropped by the Via Vignali to visit Galileo and see how his combustible friend was doing. He brought with him a letter to Galileo from their mutual friend Sagredo, who was returning from Syria and had found out by mail about Galileo’s decision to move to Florence. Sagredo, concerned, had written; Who can invent a visario which can tell the crazy person from the sane, the good neighbor from the bad?

Sarpi, it quickly became clear, felt much the same. Galileo sat down with him on the back terrace overlooking the garden, by a table of fruit and some jugs of new wine. Relaxing in this little hole in the city under the stucco walls surrounding them was something they had done many times before, for Sarpi was no ordinary priestly mentor. Like Galileo, he was a philosopher, and he had made investigations of his own in the same years Galileo had worked on mechanics, and found things such as the little valves inside human veins, and the oscillations of the pupil, and the polar attraction of magnets. Galileo had helped him with this last, and Sarpi had helped Galileo with his military compass, and even with the laws of motion.

Now the great Servite drank deeply, put his feet up, and sighed. “I’m very sorry to see you go. Things won’t be the same around here, and that’s the truth. I’ll hope for the best, but like Francesco, I’m concerned about your long-term welfare. In Venice you would have always been protected from Rome.”

Galileo shrugged. “I have to be able to do my work,” he insisted.

Sarpi’s point made him uneasy, nevertheless. No one had better reason to worry about protection from Rome than Sarpi; the evidence of that was right there in Sarpi’s horribly scarred face. Sarpi himself touched his wounds, and smiled his disfigured smile. “You know my joke,” he reminded Galileo. “I recognize the curial style”—style meaning also a kind of stiletto.

It was all part of the ongoing war between Venice and the Vatican, which was partly a public war of words—a matter of curses and imprecations so angry that at one point Pope Paul V had excommunicated the entire population of the Serenissima—but also at the same time a silent nighttime war, a vicious thing of knives and drownings. Leonardo Dona had been elected doge precisely because he was a notorious anti-Romanist, and Dona had appointed Sarpi to be his principal counselor. Then Sarpi had announced to the world his intent to write a full history of the Council of Trent, using as source material the secret files of the Venetian representatives to the Council, which were certain to contain many ugly revelations about the Vatican’s desperate campaign in the previous century to stem the tide of Protestantism. An exposé, in short. When Paul learned of Sarpi’s project, he had been so alarmed and outraged that he had authorized Sarpi’s assassination. Killers were sent to Venice, but the Venetian government had many spies in Rome, and they heard in advance that the assassins were coming, with some of them even identified by name. The Venetian authorities had arrested them on their appearance on the docks, and thrown them into prison.

After that Sarpi had accepted a bodyguard, a man who was to stay with him at all times and sleep on his doorstep.

Some of those involved in the matter were not convinced that a single bodyguard would be enough. They thought more needed to be done to protect him, because Sarpi was more important than he knew; much depended on him. As it turned out these people were proved right, so it was fortunate other protective measures were taken.

The attack on him took place on the night of October 7, 1607. A fire broke out near Santa Maria Formosa, the big church just north of San Marco. Whether the fire was set for this purpose or not, Sarpi’s fool of a bodyguard left his post at the Signoria to go have a look at it. When Sarpi was done with his business, he waited for a while for the man, then left for the Servite monastery accompanied by only an elderly servant and an old Venetian senator. He took his usual route home, which anyone could have determined by watching him for even a week: north on the Merceria, past the Rialto and Sagredo’s palazzo to the Campo di Santa Fosca. Then north over the Ponte della Pugna, the Bridge of Wrestlers, a narrow stepped bridge over the Rio de’ Servi, near the Servite monastery, where Sarpi slept in a simple monk’s cell.

They jumped him on the other side of the bridge, five of them, stabbing his companions first and then chasing Sarpi down the Calle Zancani. When they caught him they smashed him to the ground and stabbed him, but it took only a couple of seconds, then they were off into the night. Later we counted fifteen wounds.

Trailing at a discreet distance as we had been, we could only shriek and race over the bridge and kneel by the old man, applying pressure to the cuts as we found them in the flickering torchlight. The stiletto left in his right temple had apparently bent on his upper jawbone and then reemerged from his right cheek. That wound by itself looked fatal.

But for the moment he was still alive, his breath rapid and shallow, failing fast. Women were screaming from the windows overlooking the bridge, shouting directions for the pursuit of the cutthroats. Very soon we would be joined by others; already people were on the bridge calling out. But it was very dark despite the torches, so we shot him up with antibiotics and glued shut a slashed vein in the groin that was sure to kill him. Then all we could do was help to lift him up, and to carry him as gently as possible to his monastery.

There in his bare stone room he lay hovering on the edge of death, not just that night but for the next three weeks. Acquapendente came over from Padua and watched over him night and day; we could only apply antibiotics when the great doctor slept. He worried that the stiletto had been poisoned, and tried to determine whether it had been by having it stuck into a chicken and then a dog. The animals survived; and Sarpi survived too. We slipped back into our roles.

So now Sarpi could sit with Galileo, and warn him, with an ironic smile given an extra twist by his scars: “Rome can be dangerous.”

“Yes yes.” Galileo nodded unhappily. He had visited Sarpi often as he hovered between life and death. He had even helped Acquapendente to extract the stiletto from him. The pink scars were still livid. They both knew that Pope Paul had given the assailants a pension to reward them, even though they had been unsuccessful, which Galileo and Sarpi had found funny. Of course, what Sarpi was pointing out now was true: Florence was under the thumb of Rome in a way Venice had never been. If Galileo ever offended the Church, as seemed quite possible, given his new astronomical discoveries and some priestly objections to them, not to mention Kepler’s ravings—then Florence might not be far enough away from the long reach of the Dogs of God.

“I know,” Galileo said. But he was already committed to the move, and Sarpi’s example cut both ways, so to speak. Florence was an ally of Rome’s, Venice a fierce opponent, excommunicated en masse. Moving to Florence might give him some cover.

Sarpi seemed to read these thoughts on his face. “A patron is never as secure as a contract with the senate,” he said. “You know what always happens to a patron’s favored ones: they fall. Sooner or later it always happens.”

“Yes yes.” They had both read their Machiavelli and Castiglione, and the fall of the favorite was a standard trope in poetry and song. It was one of the ways that patrons showed their power, and stirred the pot, and kept those on the rise hopeful.

“So that’s another way you will not be as safe.”

“I know. But I have to be able to do my work. I have to be able to make ends meet. Neither has been possible for me in Padua. The senate could have made it possible, but they didn’t. They paid me poorly, and the workload was excessive. And they were never going to pay me just to do my own work.”

“No.” Sarpi smiled at him affectionately. “You need a patron to be able to get money without working for it.”

“I work hard!”

“I know you do.”

“And it will be useful work, both to Cosimo and everyone.”

“I know it will. I want you to do your work, you know that. May God bless you for it; I’m sure He will. But you will have to take care what you say.”

“I know.”

Galileo did not want to agree. He never wanted to agree; agreeing was something other people did, with him, after they had disagreed. People were always giving in to his superior logic and his intense style of disputation. In debate he was boastful and sarcastic, funny and smart—really smart, in that he was not just quick, but penetrating. No one liked arguing with Galileo.

But with Sarpi it was not like that. Up until this point in Galileo’s life, Sarpi himself had been a kind of patron to him, but also much more: a mentor, a confessor, a fellow scientist, a father figure. And now, even when Galileo was leaving Sarpi’s beloved Venice, a close friend. His scarred face, ruined by the pope’s murderous functionaries, held now an expression of grave concern, and of love and indulgent affection—amorevolezza. He did not agree with Galileo, but he was proud of him. It was the look you wanted your father to have when he looked at you. It could not be gainsaid. Galileo could only bow his head and dash the tears from his eyes. For he had to go.

So, after months of preparations, Galileo moved to Florence, leaving behind not only Marina and little Vincenzio, but also all his private students, and most of the servants and artisans as well, even Mazzoleni and his family. “I won’t be needing a workshop anymore,” Galileo explained brusquely. “I’m a philosopher now.” This sounded so ridiculous that he added, “The grand duke’s mechanicians will be available to me, if I need anything.”

No more compasses, in other words. No more Padua. He was saying good-bye to all of it, and didn’t want any part coming with him. “You can keep making the compasses here,” he told Mazzoleni, then turned his back and left the workshop. The compasses were what Mazzoleni had been hired to manufacture in the first place. They wouldn’t sell very well without the course Galileo gave in their use, but there were some instruction manuals left, and it was better than nothing. Besides, there was artisanal work all over Padua.

So the big house on Via Vignali was emptied, its people dispersed. One day in the fall it was handed back over to the landlord, and that whole little world was gone.

In Florence, Galileo had hastily rented a house that was a bit too near the Arno, but it had a little roof terrace for his night viewing—what the Venetians called an altana—and he figured he could find a more suitable establishment later. And a new acquaintance, a beautiful young Florentine nobleman named Filippo Salviati, assured him that during the year of his lease he could spend as much time as he liked at Salviati’s palazzo in town and at his villa, the Villa delle Selve, in the hills west of Florence. Galileo was pleased. He found the river vapors in Florence unpleasant, also the nearby presence of his mother. Since his father’s death, he had kept the old washtub in a house he rented in a poor part of the city, but he never visited her, and didn’t want to now. Better to spend his time out at Salviati’s, writing books and discussing philosophical matters with his new friend and his friend’s circle of acquaintances—men of high quality. When Cosimo wanted him, he could ride into the city quickly, and there would be no need to avoid his mother, or to fear running into her by accident.

Fra Paolo, who knew of this fear, had suggested that Galileo try to effect a reconciliation with her, but he didn’t know the half of it; indeed, he didn’t know the hundredth part of it. Galileo had recently gotten a letter from her welcoming him back to “his hometown,” and asking him to drop by and visit her, who was so lonely for him. Galileo snorted as he read this; along with everything else stuck in his memory in his pincushion of a brain, there was something new to add. In their departure from Via Vignali the cook had found a letter left behind by a servant she had fired, one Alessandro Piersanti, who had earlier worked in Florence for the old firedog. Giulia had written to him;

Since your master is so ungrateful to you and to everyone, and as he has so many lenses, you could very easily take three or four and put them at the bottom of a small box, and fill it up with Acquapendente’s pills, and then send it to me. Then, she went on, she would sell them and share the proceeds with him.

“Jesus Christ!” Galileo had shouted. “Thief on the cross!” He had thrown the letter down in disgust. Then he picked it up and saved it in his files, just in case it might be useful someday. It was dated January 9 of that year—which meant that the very week that Galileo was discovering the Medicean Stars and changing the skies forever, his own mother was conspiring to steal his spyglass lenses out of his house and sell them for her own profit. “Jesus son of Mary. Why not just steal the eyes out of my head?”

That was his mother for you. Giulia Galilei, suborner of servants, thief of the heart of his work. He would reside out at Salviati’s villa as much as he could.

Though exhausted by the move and the many sleepless nights that year, he still stayed out every clear night, looking at the stars and keeping track of Jupiter’s four moons. The Florentine nights were at first smokier than in Padua, but as the fall of his anno mirabilis moved toward winter, they turned cold enough to clarify the air. In December one of his former students, Benedetto Castelli, now a priest, wrote to suggest that if the Copernican explanation were indeed correct, then Venus was orbiting the sun also, in an orbit closer to the sun than Earth’s, so that one might therefore be able through an occhialino to see it go through phases like the moon’s, as one would be seeing either the side facing the sun or the dark side, or in between.

This thought had already occurred to Galileo, and he was irritated that he had forgotten to write it down in the Sidereus Nuncius. Then he remembered: Venus had been behind the sun the previous winter when he was writing the book, so he had been unable to check to see if the idea was right, and had thought it better to keep the notion to himself

Now he turned his best occhialino toward Venus as it appeared in the sky after sunset. In the first days of viewing it was low, a small full disk. Then as the weeks passed it rose higher and became larger, but was misshapen—possibly gibbous. Finally it was revealed in the glass to have the shape of a little half-moon, and Galileo wrote Castelli to tell him so. Eventually, when it began to sink again toward the horizon at its first twilight appearance, it was clearly horned. Galileo’s latest spyglass had a very fine objective lens that he had ground himself, and in the eyepiece the image of Venus gleamed, distinctly crescent, a miniature of the new moon that had set just an hour before.

Standing up straight, looking at the brilliant white point, feeling the moon just under the horizon and still shedding its light into the night air, suddenly it all fell into place for him. The ball of Venus and the ball of the Earth both rolled around the sun; the ball of the moon rolled around the Earth; the balls of Jupiter’s four moons circled the ball of Jupiter, which slowly circled the sun. Saturn was farther out and slower, Mercury quickest of all, there inside Venus, where it was difficult to spot. Perhaps a good enough glass would see its horns as well, for certainly it too would go through phases. So close to the sun, when visible at all it would have to be pretty near quarter phase. Farther out from Earth, Mars rolled between Earth and Jupiter, close enough to Earth to explain the strange back-and-forth aspects of its movement, a shift of perspective created by the two orbits.

The whole system was a matter of circles going around other circles. Copernicus had been right. His system had called for Venus to have phases, and there they were; while the Ptolemaic theory, advocated by the Peripatetics, would specifically reject these phases, as Venus was supposed to be going around the Earth, like the sun and everything else in the sky. Venus’s phases were a kind of proof, or at least a very suggestive piece of evidence. Tycho Brahe’s weird and unwieldy formulation, which had the planets circling the sun but the sun circling the Earth, would also save these particular appearances, but it was a ridiculous explanation in all other respects, in particular, simple parsimony. No, these phases of Venus were best explained by Copernicus.

They were the strongest indication Galileo had seen—not exactly proof, but powerfully suggestive. All those years in Padua he had taught both Aristotle and Copernicus, and even Tycho, thinking that all of them merely saved the appearances without in any sense explaining what was going on. The Copernican explanation required that the Earth be moving, which seemed wrong. And the foremost advocate of Copernicanism, Kepler, had been so long-winded and incomprehensible that no one could be convinced by him. And yet here it was, the truth of the situation—the cosmos revealed in a single stroke as being one way rather than another. The Earth was spinning under his feet, also rolling around the sun. Circles in circles.

Again he rang like a bell. His flesh buzzed like bronze, his hair stood on end. How things worked; it had to be; and he rang. He danced. He circled his occhialino like the Earth circling the sun, spinning in a slow four-step as he made his little orbit on the altana, arms swinging, fingers directing the music of the spheres, which despite Kepler’s craziness seemed suddenly plausible. Indeed an audible chord was now ringing silently in his ears.

Then came a knock on the door below. He halted his dance with a jerk, looked down the staircase on the outside of the house.

Cartophilus was there inside the gate, holding a shuttered lantern, looking up at him. Galileo rushed down the stairs and raised a fist as if to strike him. “What is this?” he exclaimed in a low furious voice. “Is he here again?”

Cartophilus nodded. “He’s here.”