Cale felt Riven tense beside him.

"Easy," Cale said to the assassin under his breath.

"You don't know anything about me, old fool," Riven said, his voice low.

Sephris sighed, the longsuffering sound of the misunderstood. He stepped out from behind his desk and walked across the library, hopping to avoid stepping on any of the papers and books, and stood in front of them. Cale readied himself to prevent Riven from doing the old man violence.

"Ten words, thirteen syllables."

"What?"

Sephris signed in exasperation and said, "The words you just spoke. Ten words, thirteen syllables. Do you believe that to be chance? Choice?"

Riven said nothing, which didn't seem to trouble Sephris.

"Not so. Not choice. The necessary answer. Two and two are always four."

For a reason Cale could not explain, hearing those words from Sephris reminded him of his attempt to articulate Fate.

"I see what you cannot," Sephris said to Riven, to all of them, "and I know what you do not." He gestured with his arms to indicate the papers on the floor. "Numbers ... formulae. The universe is an equation. Did you know that? Each of us is a sub-equation. Every question a function. Each, therefore, solvable." He looked Riven in the eye and asked, "You don't want to be solved though, do you? Fearful of the answer?"

Riven looked like he wanted to spit. His hand hovered near his blade.

"He's mad," the assassin said, but sounded unsure of himself.

"No," said Jak, "he just knows things. He just . . . thinks differently."

"Indeed," said Sephris softly, and he smiled at Jak. "Differently." He turned and walked away from them, again careful to avoid stepping on any papers or tomes. "Sit where you like. It does not matter."

None of them moved. They continued to stand just inside the door, as though fearful that to enter the library would immerse them in the same mad world in which Sephris lived.

"Do you know why we've come?" Cale asked him.

Sephris folded his hands behind his back and looked up to the ceiling.

"Many variables, of course ..."

He trailed off, muttering to himself, pacing the library, studying nothing. Cale wondered if he should ask the question again.

"Variables," Sephris muttered, "variables." He stopped walking and turned to look at Cale, his gaze sharp. "You've brought me something."

"That shows nothing," Riven said. "A Turmishan palm reader could—"

"You've brought me a half," said Sephris with a smile, "but you wish the whole."

Cale felt the hairs on his nape rise. Beside him, Riven stuttered to a stop.

"Didn't I say so?" Jak said, and shot an I told you so look at Riven. "Show him, Cale."

Cale unslung his pack.

"You require an answer within two days," said Sephris, nodding. "Two. Hmm. These formulae are complex. You three present quite the problem. Interesting...."

Cale, wondering how in the Nine Hells Sephris seemed to know what he knew, removed the half-sphere from its burlap blanket. He held it up for the loremaster to see. The gems within the quartz sparkled in the candlelight.

"We need you to tell us what this is," Cale said.

For the first time since they'd entered the library, Sephris seemed to give something his full attention. He stared at the half-sphere—hard. He seemed to have stopped breathing.

"Place it on my desk," he said. "Careful of my papers."

After a moment's hesitation, Cale walked across the library, mindful of the debris on the floor, and placed the half-globe on Sephris's desk. As he did, he looked at the slate on which Sephris had been writing. The numbers and symbols on it were written in half a dozen different languages, at least two of which Cale didn't recognize. Probably Sephris had invented his own branch of mathematics to symbolize his thinking.

"How many languages do you speak?" Cale asked in Chondathan.

Sephris waved a dismissive hand and answered in Turmishan, "There is only one, young man, and it is not written with letters. Now, move away from my desk."

Cale did.

Staring at the half-sphere throughout, the loremaster walked to his desk and sat. He put his chin in his palms and stared at it, transfixed, his eyes drinking it in, whispering to himself all the while. Cale realized as he backed toward the door that the loremaster was actually counting the flecks of gemstones within the half-sphere. Dark and empty! There were hundreds, at least—perhaps thousands.

"Is he counting the gems?" Jak asked in a whisper, when Cale had retreated back to the door.

Cale nodded, watching.

When Sephris looked up some moments later, he seemed surprised to see them there.

"You, still?" the loremaster said. "This changes everything. Everything."

He picked up his slate, wiped it clean with the sleeve of his robe and began to write furiously.

"A dominant variable," he muttered. "Dominant."

Cale, Riven, and Jak could do nothing but stand and wait while Sephris scratched his head and studied what he had written.

"No," Sephris muttered, and again he wiped the slate clean. He started anew to write but stopped and looked up at them. "Return to me in eighteen hours. I will provide you with your answer then."

"No, Sephris," Cale said. "We cannot."

He couldn't leave the half-sphere unprotected.

Sephris looked taken aback; he must not often be refused. He eyed Cale shrewdly.

"It will be safe here with me. Look." Sephris hurriedly scribbled a formula on the slate that filled it only halfway. He held it up for Cale and said, "Do you see? It will be safe until at least the nineteenth day of this month."

The scribblings meant nothing to Cale, but he needed an answer, and that meant abiding by Sephris's rules. They could keep watch from the street.

"Eighteen hours then," he agreed.

"Excellent. You may go."

At that, Riven scoffed. Under his breath he said, "By your leave, milord."

Cale said nothing. They turned, opened the door and exited. The priest-caretaker greeted them in the hall.

"Did you find what you sought?"

Cale deflected the question. "We'll return tomorrow evening."

"Very well," said the priest, content not to press. "I'll expect you then."

And that was that.

When they reached the street, Cale eyed the nearby buildings. One of them, a three story stone tallhouse, had a roof with only a slight pitch.

Cale pointed and said, "There. We'll keep watch in shifts, in case Vraggen makes another grab for the half-sphere."

In truth, Cale didn't think the mage would risk another attack, but he wanted to be certain. The tall-house roof offered a nice vantage of the entire street.

"Good," Jak said.

"I'm in," Riven said, "but there's something I need to tend to first. I'll be back before nightfall."

"Describe the something," Cale said.

"My concern, Cale."

They exchanged glares. Cale knew it would be pointless to press.

"Act as though you're being watched," he said.

Riven sneered and laid a hand on one of his enchanted sabers.

"I always do," the assassin said. "I'lll be back near sunset."

As Riven walked away, Jak said, "I don't trust him, Cale. Not as far as I could throw a troll."

Cale made no comment, just stared into Riven's back. He was not sure if he trusted the assassin either. Obviously Mask did, but that gave Cale no comfort—Mask was a bastard, after all, and always had his own agenda.

"Let's get situated on that roof."

Riven hurried through the streets, his left hand on a saber hilt, heading for the Foreign District. After he'd left the Zhents a few months earlier, he'd purchased a nondescript flat there. It still felt strange to him to have somewhere to go, somewhere he considered his home. While in the Network, he had made a habit of changing the location in which he slept at least twice per tenday, more out of a sense of professional caution than genuine fear. Riven rarely left enemies alive, and the dead didn't often carry grudges.