Bayliss was no longer with them.

Chen stepped away from Hassan and scanned the dome rapidly. The glowing logic pool was becoming more irregular in outline, spreading under the floor like some liquid. And Bayliss was working at the data desks, setting up transmit functions, plugging in data cubes.

Chen took two strides across to her and grabbed her arm. For a moment Bayliss tried to keep working, feverishly; only slowly did she become aware of Chen’s hand, restraining her.

She looked up at Chen, her face working, abstracted. “What do you want?”

“I don’t believe it. You’re continuing with your data mining, aren’t you?”

Bayliss looked as if she couldn’t understand Chen’s language. “Of course I am.”

“But this data has been gained illegally. Immorally. Can’t you see that? It’s—”

Bayliss tipped back her head; her augmented cornea shone. “Tainted? Is that what you’re trying to say? Stained with the blood of these artificial creatures, Chen?”

“Artificial or not, they are sentient. We have to recognize the rights of all—”

“Data is data, Susan Chen. Whatever its source. I am a scientist; I do not accept your—” for a moment the small, precise mouth worked “ — your medieval morality.”

“I’m not going to let you take this data out of here,” Chen said calmly.

“Susan.” Hassan was standing close to her; with a surprisingly strong grasp he lifted her hands from Bayliss’s arm.

“Keep out of this.”

“You must let her finish her work.”

“Why? For science?”

“No. For commerce. And perhaps,” he said dryly, “for the future of the race. If she is right about non-local communication—”

“I’m going to stop her.”

“No.” His hand moved minutely; it was resting against the butt of a laser pistol.

With automatic reflex, she let her muscles relax, began the ancient calculation of relative times and distances, of skills and physical conditions.

She could take him. And—

Bayliss cried out; it was a high-pitched, oddly girlish yelp. There was a clatter as she dropped some piece of equipment.

Chen’s confrontation with Hassan broke up instantly. They turned, ran to Bayliss; Chen’s steps were springy, unnatural in the tiny gravity.

“What is it?”

“Look at the floor.”

The Sky resisted for an instant. Then it crumbled, melting away like ancient doubts.

He surged through the break, strong, exultant, still growing.

He was outside the Sky. He saw arrays of new postulate fruits, virgin, waiting for him. And there was no further Sky; the Pool went on forever, infinite, endlessly rich.

He roared outwards, devouring, budding; behind him a tree of brothers sprouted explosively.

The pool surged, in an instant, across the floor and out beyond the dome. The light, squirming with logic trees, rippled beneath Chen’s dark, booted feet; she wanted, absurdly, to get away, to jump onto a data desk.

“The quantum switch.” Bayliss’s voice was tight, angry; she was squatting beside the switch, in the middle of the swamped light pool.

“Get away from there.”

“It’s not functioning. The nanobots are unrestrained.”

“No more culling, then.” Hassan stared into Chen’s face. “Well, Susan? Is this some sentimental spasm, on your part? Have you liberated the poor logic trees from their Schrödinger hell?”

“Of course not. Lethe, Hassan, isn’t it obvious? The logic trees themselves did this. They got through the Interface to Marsden’s corpus callosum. Now they’ve got through into the switch box, wrecked Marsden’s clever little toy.”

Hassan looked down at his feet, as if aware of the light pool for the first time. “There’s nothing to restrain them.”

“Hassan, we’ve got to get out of here.”

“Yes.” He turned to Bayliss, who was still working frantically at her data mines.

“Leave her.”

Hassan gave Chen one long, hard look, then stalked across to Bayliss. Ignoring the little mathematician’s protests he grabbed her arm and dragged her from the data desks; Bayliss’s booted feet slithered across the glowing floor comically.

“Visors up.” Hassan lifted his pistol and lazed through the plastic wall of the dome. Air puffed out, striving to fill the vacuum beyond.

Chen ran out, almost stumbling, feeling huge in the feeble gravity. Neptune’s ghost-blue visage floated over them, serene, untroubled.

Waves of light already surged through the substance of the moon, sparkling from its small mountaintops. It was eerie, beautiful. The flitter was a solid, shadowed mass in the middle of the light show under the surface.

Hassan breathed hard as he dragged a still reluctant Bayliss across the flickering surface. “You think the trees, the nanobots could get into the substance of the flitter?”

“Why not? Any Interface would do; they are like viruses…”

“And ourselves? Could they get across the boundary into flesh?”

“I don’t want to find out. Come on, damn it.”

Logic light swarmed across a low ridge, explosive, defiant.

“They must be growing exponentially,” Hassan growled. “How long before the moon is consumed? Days?”

“More like hours. And I don’t know if a moon-sized mass of bucky tube carbon can sustain itself against gravity. Nereid might collapse.”

Now Hassan, with his one free hand, was struggling to get the flitter’s hatch open. “It will forever be uninhabitable, at the least. A prime chunk of real estate lost.”

“The System’s big.”

“Not infinite. And all because of the arrogance of one man—”

“But,” Bayliss said, her augmented eyes shining as she stroked the data cubes at her belt, “what a prize we may have gained.”

“Get in the damn flitter.”

Chen glanced back into the ruined dome. The splayed body of Marsden, exposed to vacuum, crawled with light.

The Pool beyond the Sky was limitless. He and his brothers could grow forever, unbounded, free of Culling! He roared out his exultation, surging on, spreading—

But there was something ahead of him.

He slowed, confused. It looked like a brother. But so different from himself, so changed.

Perhaps this had once been a brother — but from a remote branch which had already grown, somehow, around this greater Pool.

The brother had slowed in his own growth and was watching. Curious. Wary.

Was this possible? Was the Pool finite after all, even though unbounded? And had he so soon found its limits?

Fury, resentment, surged through his mighty body. He gathered his strength and leapt forward, roaring out his intent to devour this stranger, this distant brother.

Eve said, “The great wormhole network covered the System. And everywhere, humans found life…”

The flitter bucked.

Lvov looked up from her data desk, startled. Beyond the flitter’s translucent hull, the wormhole was flooded with sheets of blue-white light which raced towards and past the flitter, giving Lvov the impression of huge, uncontrolled speed.

“We’ve got a problem,” Cobh said. The pilot bent over her own data desk, a frown creasing her thin face.

Lvov had been listening to her data desk’s synthesized murmur on temperature inversion layers in nitrogen atmospheres; now she tapped the desk to shut it off. The flitter was a transparent tube, deceptively warm and comfortable. Impossibly fragile. Astronauts have problems in space, she thought. But not me. I’m no hero; I’m only a researcher. Lvov was twenty-eight years old; she had no plans to die — and certainly not during a routine four-hour hop through a Poole wormhole that had been human-rated for fifty years.

She clung to her desk, her knuckles whitening, wondering if she ought to feel scared.