“You don’t believe any of that shit, do you?”

“Why should I not?” Galileo replied sotto voce, in Tuscan.

“Don’t be so sure your companion has your best interests here, no matter that you are the great martyr to science.”

Galileo, not liking the sound of that, said quickly, “What do you think my interests here are?”

“The same as anywhere,” she said with a sly smile. “Your own advancement, right?”

In the midst of a fierce harangue at his foes, the stranger looked over and noticed the woman and Galileo in conversation. He stopped arguing with the others and wagged a finger at her. “Hera,” he warned her, “leave him alone.”

She raised an eyebrow. “You are not the one to be telling people to leave Signor Galileo alone, it seems to me.” This was still translated to Galileo in Tuscan.

The stranger frowned heavily, shook his head. “You have nothing at stake here. Leave us alone.” He returned to addressing the entire group, which was now quieting to hear what was going on.

“This is the one who began it all,” the stranger boomed, while in his other ear Galileo heard the woman’s voice in Tuscan, saying, “He means, this is the one I chose to begin it all.”

The stranger continued without further sotto voce commentary from the woman he had called Hera. “This is the man who began the investigation of nature by means of experiment and mathematical analysis. From his time to ours, using this method, science has made us what we are. When we have ignored scientific methods and findings, when the archaic structures of fear and control have reexerted themselves, stark disaster has followed. To abandon science now and risk a hasty destruction of the object of study would be stupid. And the result could be much worse than that—much worse than you imagine!”

“You have already made this argument, and lost it,” a red-faced man said firmly. “The Europan interior can be investigated using an improved clean protocol, and we will learn what we have wanted to learn for many years. Your view is antiquated, your fears unfounded. What you did on Ganymede has damaged your understanding.”

The stranger shook his head vehemently. “You don’t know what you’re talking about!”

“I am only affirming what the scientific committee assigned to the problem has already said. Who’s being unscientific now, them or you?”

A general debate erupted again, and under its noise Galileo said to the tall woman, “What is it that my patron and his allies want to forbid?”

She leaned in to him to reply, in Italian again. “They don’t want anyone to dive into the ocean under the ice here. They fear what might be encountered there, if I understand the Ganymede correctly.”

Then a group of men dressed in the blue shade of clothing came bouncing down the steps on the other side of the amphitheater. A senator dressed in the same color gestured at them and cried at the stranger, “Your objection has already been overruled! And you are breaking the law with this incursion. It’s time to put a stop to it.” He shouted up at the newcomers, “Eject these people!”

The stranger grabbed Galileo by the arm and hustled him in the other direction. His allies closed behind them, and they raced up the steps two at a time. Galileo almost tripped, then felt himself being lifted by the people on each side of him. They held him under the elbows and carried him.

At the top of the steps, out of the hole of the amphitheater, they could suddenly see across the expanse of the blue city again, looking cold under its green-blue ceiling, the people on its broad strada so distant they were the size of mice. “To the ships,” the stranger declared, and took Galileo by the arm. As he hustled Galileo away, he said to him, “It’s time to return you to your home, before they do something we will all regret. I’m sorry they would not listen to you. I think if you had been able to judge the situation, you would have sided with us and made our point clear. I’ll call on you again when I am more sure you will be listened to. You are not done here!”

They came to the broad ramp rising out of the city, through its gates and onto the yellowy surface. People dressed in blue stood in their way, and with a roar the stranger and his group rushed at them. A brisk fight ensued, and Galileo, staggering in the absence of his proper weight, dodged around little knots of brawlers. If he had been dreaming, he would have happily started throwing punches himself, for in his dreams he was much more audacious and violent than in life. So it was a measure of how different this was from a dream, how real it was, that he held back. He wasn’t even sure which side he should have been supporting. So he skidded through the fray as if on the frozen Arno, waving his arms as needed to restore his balance. Suddenly in his gyrations, the stranger and another man snatched him up by the arms and hustled him away.

Some distance from the melee, the stranger’s companions had set up the big spyglass, and were making final adjustments to it. It was either the same one that had stood on Galileo’s terrace, or one just like it.

“Stand next to it, please,” the stranger said. “Look into the eyepiece, please. Quickly. But before that—breathe this first—”

And he held a small censer up and sprayed a cold mist into Galileo’s face.

CHAPTER FOUR

The Phases of Venus

In order not to burden too much the transmigrating souls, Fate interposes the drinking from the Lethean river in the midst of the mutations, so that through oblivion they may be protected in their affections and eager to preserve themselves in their new state.

—GIORDANO BRUNO, Spaccio del la Bestia Trionfante (The Expulsion of the Triumphant Beast)

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.”