In the last year of his sight, he often sat out in the garden at night on his reclined divan, looking at the moon and what he could see of the stars. He noticed for the first time that although the moon always showed the same face to Earth, it was not exactly the same face; there were small shifts, as if the man in the moon were looking into a mirror and inspecting his face from different angles—which is how Galileo put it when he wrote about the discovery to his friends—first tipping his head down, then up, then left, then right. This might be part of how the moon had its effect on the tides; for his theory, that they were caused not by the moon but by the Earth’s rotation and its movement around the sun, had turned out to be not just heretical, but wrong. The moon seemed to be involved after all; or at least things were happening to both moon and tides in concert. Possibly this shifting face had something to do with it. So hard to tell; but when he understood the reality of this little libration, which no watcher of the moon no matter how vigilant had ever observed in the history of mankind, the little bell inside him rang again.

That bobbing face of the man in the moon was his last observation; soon after that his left eye went too, and then that kind of thing was truly over. A combination of infections and cataracts had blinded him. Only a short time after that, the Vatican sent word that he was allowed to move temporarily into Florence to be seen to by doctors. But it was doubtful they could have done anything, even if they had seen him before.

With his world gone dark, he had to dictate his letters, which continued to go out into the world as before. A young student named Vincenzio Viviani, only seventeen years old, was invited to move into the house as an assistant. He joined us and proved to be a serious young man, intelligent and helpful, very intent on his duties. Galileo spent many an hour talking through his correspondence, and Viviani wrote it all down.

In a letter to Diodati, Galileo said,

This universe, which I with my astonishing observations and clear demonstrations enlarged a hundred, nay, a thousandfold beyond the limits commonly seen by wise men of all centuries past, is now for me so diminished and reduced as to have shrunk to the meager confines of my own body.

When he said gloomy things like this around the household, I would say to him, “It could be worse.”

“Worse?” he would snap. “Nothing could be worse! It would have been better to have been burned at the stake by that liar who went back on his word!”

“I don’t think so, maestro. You wouldn’t have liked the fire.”

“At least it would have been fast. This falling apart, one piece at a time—if only I would trip on a stair and hit my head and be gone. So leave me! Leave me or I’ll kick you. I know where you are.”

He could tell many weeds by feel, and so continued to sit in the garden in the mornings, even when he did nothing but listen to the birds and feel the sun on his face. He got out his lute, had it repaired and re-strung, and started playing it again. As the calluses on his fingers thickened he played it more and more, repeating the songs he knew, and humming or mumbling in a hoarse baritone the words to some of them. He often played a little suite of his father’s compositions, and musical settings for Ariosto and Tasso, and long wandering melodies of his own devise. La Piera ran the house along with Geppo and the other longtime servants. Viviani served as Galileo’s amanuensis. I continued on as his personal servant. A new student, Torricelli, moved in to take mathematics lessons. Things continued in their new way.

And then Alessandra Buonamici came back. She showed up in the spring of 1640, announcing that her husband’s diplomatic assignment had unexpectedly brought him back to Florence. She stood there in his room; she touched him on the arm, let him touch her on the face. “Yes, I’m here,” she said.

AGAIN GALILEO WAS SAVED BY A STRANGER appearing at a crux in his life. This time it was Alessandra, nearly forty now, childless, tall, and rotund. She came to visit almost every day, accompanied only by a servant or two. She brought with her gifts for him that he could feel, or eat: rolls of yarn, different fabrics of linen, dried fruits, scraps of blacksmith metal, polygons made of woodblock, chunks of coral. He would sit forward in his chair and rub swatches between his fingers and against his cheek, or stack cubes, and tell her about cohesion and the strength of wood.

I long to talk to you, he wrote when she could not come. It is so rare to find women who can speak so sensibly as you.

She replied even more boldly: I have been trying to find the way to come there and stay for a day of conversation with you, without creating scandal. She suggested fantasy plans, things that could never happen but that she knew would please him to imagine—that they might go boating on the Arno, that she might slip a small carriage into Arcetri to spirit him away to Prato for several days together, and so on. Patience! she wrote.

I have never doubted your affection for me, he wrote back, certain that you, in this short time that I may have left, know how much affection flows in me for you. He invited her to come with her husband and stay for four days. Somehow this never happened.

Life at Il Gioièllo contracted in on itself, orchestrated by La Piera and performed by the entire household, with the youth Viviani almost always at the maestro’s side, to the point where Galileo sometimes ordered him to go away. Many days he only wanted to lie on the divan in the shade, or sprawl in the dirt of the garden, tugging up weeds. You could see that groveling in the soil, embracing it, was a comfort to him. He curled on his side in a posture just like Arcangela’s.

But he was famous all over Europe, because of his books, and the trial. Foreign travelers often inquired if they could come to visit him. He always agreed to these requests, which flattered his vanity, and also broke the daily routine and helped pass the time. He only requested that the visitors be discreet, and generally they were, at least beforehand. After they left, they often wanted to tell the world the story of their visit. That was gratifying. He was still a figure on the great stage of Europe—an old lion, defanged and blind, but a lion still. To the Protestants he was yet another image of the corruption of the Roman Catholic Church, which was not a role that he liked to play; he felt he was a victim not of the Church but of corruption within the Church, as he tried to make clear if he got the chance.

I do not hope for any relief, he wrote to a supporter named Peiresc, and that is because I have committed no crime. I might hope for a pardon if I had erred. With the guilty a prince can show forbearance, but against one wrongfully sentenced when he is innocent, it is expedient to uphold rigor, so as to put up a show of strict lawfulness. This was like something out of Machiavelli, a writer Galileo knew well. Galileo had met his prince too, and suffered the consequent tortures just as Machiavelli had.

Apparently a translated edition of the Dialogo had been published in England; Galileo had no idea, until Englishmen began to appear at his gate. One of the first of them, a Thomas Hobbes, told him of the translated edition and then wanted to talk philosophy, and get Galileo to say things he didn’t want to say. Because they conversed in Latin (and the English way of pronouncing Latin was very strange, like something he seemed to recall), he was able to bend the talk to topics he was comfortable discussing. Thus Hobbes went away without any denunciations or blasphemies to quote.