"Hmm …" said Riva. She and the sandy-haired youth went into close math-gibberish-mode, punctuated by some reprogramming of the simulation console. The first colorful display was rejected by them both with the muttered comment, "That's not right. . . ."A couple more went by. Riva sat back at last, and ran her hands through her short curls. "Any chance of taking this home to sleep on overnight?"

"Ah," said Lord Auditor Vorthys. "I'm afraid I was unclear to you over the comconsole last night. This is something in the nature of a crash program, here. We have reason to suspect time could be of the essence. We're all here for the duration, till we figure this out. No data leave this building."

"What, no dinner at the Top of the Dome in Serifosa?" said Yuell, sounding disappointed.

"Not tonight," Vorthys apologized. "Unless someone gets really inspired. Food and bedding will be supplied by the Emperor."

Riva glanced around the room, and by implication the facility. Is this going to be the ImpSec Budget Hostel again? Bedrolls and ready-meals?"

The Professor smiled wryly. "I'm afraid so."

"I should have remembered that part from the last time. . . . Well, it's motivation of a sort, I suppose. Yuell, that's enough of this comconsole for now. Something's not right. I need to pace."

"The corridor is at your disposal," Professor Vorthys told her cordially. "Did you bring your walking shoes?"

"Certainly. I did remember that from our last date." She stuck out her legs, displaying comfortable thick-soled shoes, and rose to go off to the hallway. She began walking rapidly up and down, murmuring to herself from time to time.

"Riva claims to think better while walking," Vorthys explained to Miles. "Her theory is that it pumps the blood up to her brain. My theory is that since no one can keep up with her, it cuts down on the distracting interruptions."

A kindred spirit, by God. "Can I watch?"

"Yes, but please don't talk to her. Unless she talks to you, of course."

Both Vorthys and Yuell returned to fooling with their comconsoles. The Professor appeared to be trying to refine his hypothetical design for the missing power-supply system or the novel device. Miles wasn't sure but what Yuell was playing some sort of mathematical vid game. Miles leaned back in his station chair, stared out the window, and addressed his imagination to the question, If I were a Komarran conspirator with ImpSec on my tail and a novel device the size of a couple of elephants, where would I hide it? Not in his luggage, for damn sure. He scratched out ideas on a flimsy, and drew rejecting lines through most of them. D'Emorie studied the Professor's work and reran some of the earlier simulations.

After about three-quarters of an hour, Miles became aware hat the echo of soft rapid footsteps from the corridor had eased. He rose, and went and poked his head out the door. Dr. Riva was seated on a window ledge at the end of the corridor, gazing pensively out over the Komarran landscape. It fell away toward the stream, here, and was much less bleak than the usual scene, being liberally colonized by Earth green. Miles ventured to approach her.

She looked up at him with her quick smile as he neared, which he returned. He hitched his hip over the low ledge, and followed her gaze out the sealed window, then turned to study her profile. "So," he said at last. "What are you thinking?"

Her lips twisted wryly. "I'm thinking . . . that I don't believe in perpetual motion."

"Ah." Well, if it had been easy, or even just moderately difficult, the Professor would not have called for reinforcements, Miles reflected. "Hm."

She turned her gaze from the scenery to him, and said after a moment, "So, you're really the son of the Butcher?"

"I'm the son of Aral Vorkosigan," he replied steadily.

"Yes." Her version of the perpetual question was neither the accidental social blunder of Tien, nor the deliberate provocation of Venier. It seemed something more . . . scientific. What was she testing for?

"The private life of men of power isn't what we expect, sometimes."

He jerked up his chin. "People have some very odd illusions about power. Mostly it consists of finding a parade and nipping over to place yourself at the head of the band. Just as eloquence consists of persuading people of things they desperately want to believe. Demagoguery, I suppose, is eloquence sliding to some least moral energy level." He smiled bleakly at his boot. "Pushing people uphill is one hell of a lot harder. You can break your heart, trying that." Literally, but he saw no point in discussing the Butcher's medical history with her.

"I was given to understand that power politics had chewed you up."

Surely she could not see scars through his gray suit. "Oh," Miles shrugged, "the prenatal damage was just the prologue. The rest I did to myself."

"If you could go back in time and change things, would you?"

"Prevent the soltoxin attack on my pregnant mother? If I could only pick one event to change . . . maybe not."

"What, because you wouldn't want to risk missing an Auditorship at thirty?" Her tone was only faintly mocking, softened by her wry smile. What the devil had Vorthys told her about him, anyway? She was highly aware, though, of the power of an Emperor's Voice.

"I almost arrived at thirty in a coffin, a couple of times. An Auditorship was never an ambition of mine. That appointment was a caprice of Gregor's. I wanted to be an admiral. It's not that." He paused, and drew in breath, and let it out slowly. "I've made a lot of grievous mistakes in my life, getting here, but … I wouldn't trade my journey now. I'd be afraid of making myself smaller."

She cocked her head, measuring his dwarfishness, not missing his meaning. "That's as fair a definition of satisfaction as any I've ever heard."

He shrugged. "Or loss of nerve." Dammit, he'd come out here to pick her brain. "So what do you think of the novel device?"

She grimaced, and rubbed her hands slowly, palm to palm. "Unless you want to posit that it was invented for the purpose of giving headaches to physicists, I think . . . it's time to break for lunch."

Miles grinned. "Lunch, we can supply."

Lunch, as threatened, was indeed military-issue ready-meals, though of the highest grade. They all sat around one of the tables in the long room, pushed aside chunks of equipment to make space, and tore off the wrappers from the self-heating trays. The Komarrans eyed their food dubiously; Miles explained how it could have been much worse, getting a giggle from Riva. The conversation became general, touching on husbands and wives and children and tenure and an exchange of scurrilous anecdotes about the fecklessness of former colleagues. D'Emorie had a couple of good ones about early ImpSec cases. Miles was tempted to top them with a few about his cousin Ivan, but nobly refrained, though he did explain how he'd once sunk himself and his personal vehicle in several meters of arctic mud. This led to the subject of the progress of Komarran terraforming, and so by degrees back to work. Riva, Miles noticed, grew quieter and quieter.

She maintained her silence as they all took to the corn-consoles again after lunch. She did not resume her pacing. Miles watched her covertly, then less covertly. She reran several simulations, but did not play with further alterations. Miles knew damn well one couldn't hurry insight. This kind of problem-solving was a lot more like fishing than like hunting: waiting patiently and, to a degree, helplessly, for things to rise up out of the depths of the mind.