“You remind me of someone,” Galileo said. “I wish I could remember.”

“We are all everyone. And we all remember everything.”

On her way out she looked at me and shook her head. “I have to go,” she said. “I can’t do this anymore. Not when he could be fixed in a day.”

She didn’t come the next day, sending a letter instead. Viviani read it to Galileo, and he heard it silently. He dictated his reply.

Your letter found me in bed gravely indisposed. Many, many thanks for the courtesy that you have always shown to me, and for your condolences that visit me now in my misery and my misfortune.

That was his last letter. A few days later he fell unconscious. That night the wolves out on the hills howled, and he struggled on his bed such that it seemed to us that he heard them calling. At dawn he died.

The household wandered around in the raw morning light. Of course it was true that we had just lost our employer, and this was no small part of our despair: Sestilia notwithstanding, Vincenzio could be counted on for nothing. But it was more than that: it was also immediately obvious that with the maestro gone the world would never again be so interesting. We had lost our hero, our genius, our own Pulcinella.

It was La Piera who pushed us through the awful duties of that day and those that followed. “Come on, get on with it,” she would say. “We are all souls, remember? We exist in each other. To get him back you just have to think of what he would do, what he would say.”

“Ha,” Mazzoleni said mournfully. “Good luck with that!”

FERDINANDO II APPROVED Viviani’s plan for a grand memorial to Galileo, which would have included public funeral orations and the construction of a marble mausoleum; but Pope Urban VIII denied permission for either. Ferdinando submitted to this denial, and so Galileo’s body was buried privately, in the novice’s chapel of the Franciscan church of Santa Croce, in a chapel room under the campanile. This impromptu crypt was almost an unmarked grave.

But Pope Urban was sixty-four, while Vincenzio Viviani was only nineteen. When Urban died, in 1644 (at quarter after eleven one morning, and it was said that by noon his statues in Rome had all been pulled down and pulverized by angry mobs), Viviani had fifty-five more years of life to live, and every day of those years he devoted to the memory of the maestro. He paid for the design of a monument, to be located in San Croce across from the tomb of the great Michelangelo; their tombs would then make a matched pair, Art and Science together holding up the Church. While he worked to get this monument approved and built, Viviani spent many years collecting all of Galileo’s papers that he could find; and somewhere along the way he began writing a biography.

Once while he was at work on this project, he found me in Arcetri and enlisted my help. “What can you tell me about Signor Galileo, Cartophilus?”

“Nothing, Signor Viviani.”

“Come on, nothing? You must know something we don’t know.”

“He had a hernia. And he had trouble sleeping.”

“All right, shut up then. But help me now to make a search of San Matteo.”

“How can we do that?”

It turned out he had a certificate from the local priest allowing us into the convent. He was hoping to find Galileo’s letters to Maria Celeste, to add them to the immense collection of papers and notebooks and volumes that now filled an entire room of his house. So far Galileo’s letters to his daughter had not been found, although they had to have numbered at least as many as the ones she had sent to him—a pile that Viviani possessed, still in their basket. Knowing Galileo’s prolixity, and whom he had been writing to, this correspondence presumably formed a unique look into his thinking, and also a considerable physical mass, difficult to conceal. And now, for Viviani, of consuming interest.

But we couldn’t find them. Viviani speculated that the nuns had burned them for fear of harboring some kind of heresy, or that they had simply been thrown out or used to start kitchen fires, no one could say. But they could not be found. In fact I had found and destroyed them years earlier, for it turned out that during some of his lucid years he had written to her such detailed accounts of his Jovian experiences that there would have been no way to explain them away.

More years passed, and Viviani wrote his biography of the maestro in the most devoted, hagiographic terms possible. He got it published, but he could see that the big tomb he wanted was not going to get built in his lifetime. The Medici had lost their nerve, if they had ever had any in this matter, and Rome was implacable.

Finally, when Viviani was getting to be an old man himself, he had a plaque cast and affixed to the entryway to the little room where Galileo was buried in San Croce. He wrote into his will a request that he be buried in that same room. Then he took the front door off of his house, and turned the front façade of the building into a kind of archway. We helped him with the plastering of this façade, as Salvadore and Geppo had become bricklayers, and when that was done we cemented a bust of Galileo over the open doorway. This improvised memorial arch stood forlornly on the street of a shabby residential district of Florence, looking like the occasional architectural oddity you see in modest neighborhoods when a homeowner has lost his mind with pride of ownership. Viviani was a bit like those people, in fact, but he was such a serious man, so devoted to all the good causes of the city, and always writing to scientists all over Europe, that it was hard to joke with him about it. We plastered long marble panels vertically into each side of the arch, and on these Viviani listed Galileo’s accomplishments, painting the words on the marble very carefully as guides for me to chip away at with a chisel.

While we worked, he and I sometimes talked about the maestro and what was going on with his reputation. Viviani expressed great disdain for the Frenchman Descartes, who had been too chicken to publish anything controversial after Galileo’s condemnation, but who had recently distributed a long critique of the maestro’s Discorsi in which he listed no less than forty supposed mistakes—all but two of which were actually his own mistakes, Viviani judged, with Galileo in the right of it. I had to laugh when Viviani said that one of the things Descartes had gotten right was to scoff at Galileo for believing in the story of the burning mirrors of Archimedes.

Viviani, still offended by Descartes’ impertinence, only shook his head at my surprised painful laughter. Geppo and Salvadore tried to ignore his seriousness and distract him with teasing remarks about how funny his house was going to look after all this work, and how cold the entryway was going to be without a door, but he only stepped back to look at it again, and sighed. “Someone’s got to do it,” he said. “Hopefully my nephews will pick up the torch.” He had never married or had children, and now he shook his head. “I’m not sure about them, but I hope someone will do it.”

His had been a strange life, it occurred to me. To meet the maestro, blind and old, when you were seventeen; work with him till he died, when you were nineteen; then for the rest of your life, work for him still. I stopped my chipping and put a hand to his shoulder. “Many will do it, Signor. You’ve made a good start. Saving his papers was huge. No one could have done that but you. You’ve been a faithful student, a real Galilean.”

So I thought, at that point. But the border between devotion and madness is so narrow. Several years later, he came around to the little warren of low houses tucked behind San Matteo, and there he found me again, as ancient as ever, but no more so. It was impossible to tell how old I was. After a while it just seems like forever.