Planets were rare, here in the Core of the Galaxy; the stars were too close-packed for stable systems to form. But there was plenty of dust and ice, and it gathered into great swarms of asteroids. Some of the base asteroids were unworked — just raw rock, still the lumpy aggregates they had been when tethered and gathered here. The rest had been melted, carved, blown into translucent bubbles like the Barracks Ball. Worked or not, they were all wrapped in stabilizing superconductor hoops, like presents wrapped in gleaming electric blue ribbon, and they all had Higgs field inertia-control facilities mounted on their surfaces. The Higgs facilities gave a gravity of a standard unit or so on the worldlets’ surfaces, and provided stable fields in their interior: tiered for a Barracks Ball, more complex in other Rocks depending on their uses.

And the generators drew the Rocks to each other. Mutually attracting, they swooped and swirled about each other in an endless three-dimensional dance, mad miniature planets free of the stabilizing influence of a sun. Some of the Rocks swam so close to the flitter that you could see maintenance crews working on the surfaces, crawling over the tightly curved horizons like bugs on bits of food.

Pirius saw, bemused, that Nilis kept his eyes closed all the way through the hop.

Pirius had his mind on bigger issues. So his whole life was suddenly defined by whatever that arrogant clone of himself had done downstream! He wished he could meet Pirius Blue alone to have it out.

Nilis’s room, deep in the belly of Officer Country, was small. It was unfurnished save for a low bunk, a desk with a chair, and a nano-food niche. Pirius sat awkwardly on the bunk, and declined an offer of food or drink. Nilis himself sipped water. The walls of the room were translucent, as were all the walls throughout the Base, but they were buried so deep in this warren of offices and conference rooms that the sky beyond could barely be glimpsed.

“Which is the way I prefer it, I’m afraid,” Nilis said with a rueful smile. He sat on the room’s single chair, his robes awkwardly rucked up to expose scrawny shins. “You have to understand that I’m from Earth, where I live as humans did in primitive times — I mean, on an apparently flat world, under a dome of sky scattered with a few distant stars. Here the worlds fly around like demented birds, and even the stars are glaring globes. Of course only the most massive stars can form here; conditions are too turbulent for anything as puny as Sol… It’s rather disorienting!”

Pirius had never thought about it. “I grew up here, sir.”

“Call me Nilis.”

But Pirius was not about to call a Commissary, even a soft eccentric Commissary like this one, anything but “Sir.” He said, “Arches doesn’t seem strange to me.”

“Well, I suppose it wouldn’t.” Nilis got to his feet, cup of water in his liver-spotted hand, and he peered out through layers of offices at the wheeling sky. “A self-gravitating system — a classic demonstration of the n-body problem of celestial mechanics. And chaotic, unstable to small perturbations, never predictable even in principle. No doubt this endless barrage has been designed as conditioning, to get you proto-pilots used to thinking in shifting three-dimensional geometries, and to program out ancient fears of falling — an instinct useful when we descended from the trees, not so valuable for a starship pilot, eh? But for me, it’s like being trapped in some vast celestial clockwork.”

Irritated, distressed, Pirius blurted, “Forgive me, sir, but I don’t understand why I’m here. Or why you’re here.”

Nilis nodded. “Of course. Cosmic special effects pale into insignificance beside our human dilemmas, don’t they?”

“Why must I be punished? I haven’t done anything. It was him — he did it all.”

Nilis studied him. “Has your training not covered that yet? I keep forgetting how young you all are. Pirius, what Blue has done is done; it is locked in his timeline — his personal past. He must be punished, yes, in the hope of eradicating his character flaws. Whereas you are to be punished in the hope of changing your still unformed timeline. We can’t change his past, but we can change your future, perhaps. Do you see? And so you must suffer for a crime you haven’t yet committed.

“At least, that’s the logic of the system. Is it right or wrong? Who’s to say? We humans haven’t evolved to handle time-travel paradoxes; all this stretches our ethical frameworks a little far. And, you know, I really can’t imagine how it must be for you, Pirius Red. How does it feel to confront a version of yourself plucked out of the future and deposited in your life?”

“Sir, we train for it. It’s not a problem.”

Nilis sighed. He said, with a trace of steel in his voice, “Now, Pirius, I am here to help you, but I’m not going to be able to do that if you’re not honest with me. Try again.”

Pirius said reluctantly, “I feel — irritated. Resentful.”

Nilis nodded. “That’s better. Good. I can understand that. After all, your own future has suddenly been hijacked by this stranger, hasn’t it? Your choices taken away from you. And how do you feel about him — Pirius Blue, your double — regardless of what he has done?”

“It’s difficult,” Pirius said. “I don’t like him. I don’t think he likes me. And yet I feel drawn to him.”

“Yes, yes. You are like siblings, brothers; that’s the nearest analogy, I think. You are rivals — the two of you are competing for a single place in the world — you might even grow to hate him. And yet he will always be a part of you.”

Pirius was uncomfortable; this talk of “brothers” was seriously non-Doctrinal. “Sir, I wouldn’t know about brothers. I grew up in cadres.”

“Of course you did. Popped from the birthing tanks, placed in a training cadre, plucked out and moved on, over and over! You don’t know what it’s like to have a brother — how could you? But I know,” he said, and sighed. “There are corners, even on Earth itself, where people find room to do things the old way. Of course I had to give all that up when I joined the Commission. How unfortunate for you; if only your cultural background were richer, it might help you cope better now. Don’t you think?”

None of this meant much to Pirius. “Sir, please—”

“You want to know what an old buffoon like me is doing all the way out here.” He smiled. “I volunteered. As soon as I heard the particulars of the case, I knew I had to get involved. I volunteered to act as counsel to you and your twin.”

“But why?”

“You know that I’m a Commissary.” That meant he worked for the Commission for Historical Truth, the grand, ancient agency dedicated to upholding the purity of the Druz Doctrines — a task it performed with persuasion and force, with zeal and dedication. “What you probably don’t know is that the Commission itself has many divisions. The Commission is thousands of years old, Pirius. Astonishing when you think of it! The Commission has lasted longer than many of Earth’s civilizations. And it has grown into a very old, very tangled, bureaucratic tree.

“I work for a department called the Office of Technological Archival and Control. We’re a sort of technological think tank. If somebody gets a bright idea on Alpha Centauri III, we make sure it’s passed on to Tau Ceti IV.” These were places Pirius had never heard of. “But the name says everything: Archival and Control. Not a word about innovation, eh? Or development? The Commission’s cold hand is at our throats, and our opportunity to think is restricted. Because that’s the last thing the high-ups want us to do. Oh, yes, the very last. And that’s why I’m here. Do you see?”

Pirius tried to pick his way through all this. “No, sir, I don’t.”

“I heard about your heroics — or rather, Pirius Blue’s. I knew that to have captured a Xeelee, even to have survived such an encounter, he must have innovated. He must have found some new way of striking back at our perennial foe. And I’ve come to find out what that is. Of course, I’m unqualified for the job, and from the wrong corner of the Commission. I had to fight my way through a few administrative thickets to get this far, I can tell you.”