The room in which Jeffreyssai received his non-beisutsukai visitors was quietly formal, impeccably appointed in only the most conservative tastes.  Sunlight and outside air streamed through a grillwork of polished silver, a few sharp edges making it clear that this wall was not to be opened.  The floor and walls were glass, thick enough to distort, to a depth sufficient that it didn't matter what might be underneath.  Upon the surfaces of the glass were subtly scratched patterns of no particular meaning, scribed as if by the hand of an artistically inclined child (and this was in fact the case).

Elsewhere in Jeffreyssai's home there were rooms of other style; but this, he had found, was what most outsiders expected of a Bayesian Master, and he chose not to enlighten them otherwise.  That quiet amusement was one of life's little joys, after all.

The guest sat across from him, knees on the pillow and heels behind.  She was here solely upon the business of her Conspiracy, and her attire showed it:  A form-fitting jumpsuit of pink leather with even her hands gloved—all the way to the hood covering her head and hair, though her face lay plain and unconcealed beneath.

And so Jeffreyssai had chosen to receive her in this room.

Jeffreyssai let out a long breath, exhaling.  "Are you sure?"

"Oh," she said, "and do I have to be absolutely certain before my advice can shift your opinions?  Does it not suffice that I am a domain expert, and you are not?"

Jeffreyssai's mouth twisted up at the corner in a half-smile.  "How do you know so much about the rules, anyway?  You've never had so much as a Planck length of formal training."

"Do you even need to ask?" she said dryly.  "If there's one thing that you beisutsukai do love to go on about, it's the reasons why you do things."

Jeffreyssai inwardly winced at the thought of trying to pick up rationality by watching other people talk about it—

"And don't inwardly wince at me like that," she said.  "I'm not trying to be a rationalist myself, just trying to win an argument with a rationalist.  There's a difference, as I'm sure you tell your students."

Can she really read me that well?  Jeffreyssai looked out through the silver grillwork, at the sunlight reflected from the faceted mountainside.  Always, always the golden sunlight fell each day, in this place far above the clouds.  An unchanging thing, that light.  The distant Sun, which that light represented, was in five billion years burned out; but now, in this moment, the Sun still shone.  And that could never alter.  Why wish for things to stay the same way forever, when that wish was already granted as absolutely as any wish could be?  The paradox of permanence and impermanence: only in the latter perspective was there any such thing as progress, or loss.

"You have always given me good counsel," Jeffreyssai said.  "Unchanging, that has been.  Through all the time we've known each other."

She inclined her head, acknowledging.  This was true, and there was no need to spell out the implications.

"So," Jeffreyssai said.  "Not for the sake of arguing.  Only because I want to know the answer.  Are you sure?"  He didn't even see how she could guess.

"Pretty sure," she said, "we've been collecting statistics for a long time, and in nine hundred and eight-five out of a thousand cases like yours—"

Then she laughed at the look on his face.  "No, I'm joking.  Of course I'm not sure.  This thing only you can decide.  But I am sure that you should go off and do whatever it is you people do—I'm quite sure you have a ritual for it, even if you won't discuss it with outsiders—when you very seriously consider abandoning a long-held premise of your existence."

It was hard to argue with that, Jeffreyssai reflected, the more so when a domain expert had told you that you were, in fact, probably wrong.

"I concede," Jeffreyssai said.  Coming from his lips, the phrase was spoken with a commanding finality.  There is no need to argue with me any further:  You have won.

"Oh, stop it," she said.  She rose from her pillow in a single fluid shift without the slightest wasted motion.  She didn't flaunt her age, but she didn't conceal it either.  She took his outstretched hand, and raised it to her lips for a formal kiss.  "Farewell, sensei."

"Farewell?" repeated Jeffreyssai.  That signified a higher order of departure than goodbye.  "I do intend to visit you again, milady; and you are always welcome here."

She walked toward the door without answering.  At the doorway she paused, without turning around.  "It won't be the same," she said.  And then, without the movements seeming the least rushed, she walked away so swiftly it was almost like vanishing.

Jeffreyssai sighed.  But at least, from here until the challenge proper, all his actions were prescribed, known quantities.

Leaving that formal reception area, he passed to his arena, and caused to be sent out messengers to his students, telling them that the next day's classes must be improvised in his absence, and that there would be a test later.

And then he did nothing in particular.  He read another hundred pages of the textbook he had borrowed; it wasn't very good, but then the book he had loaned out in exchange wasn't very good either.  He wandered from room to room of his house, idly checking various storages to see if anything had been stolen (a deck of cards was missing, but that was all).  From time to time his thoughts turned to tomorrow's challenge, and he let them drift.  Not directing his thoughts at all, only blocking out every thought that had ever previously occurred to him; and disallowing any kind of conclusion, or even any thought as to where his thoughts might be trending.

The sun set, and he watched it for a while, mind carefully put in idle.  It was a fantastic balancing act to set your mind in idle without having to obsess about it, or exert energy to keep it that way; and years ago he would have sweated over it, but practice had long since made perfect.

The next morning he awoke with the chaos of the night's dreaming fresh in his mind, and, doing his best to preserve the feeling of the chaos as well as its memory, he descended a flight of stairs, then another flight of stairs, then a flight of stairs after that, and finally came to the least fashionable room in his whole house.

It was white.  That was pretty much it as far as the color scheme went.

All along a single wall were plaques, which, following the classic and suggested method, a younger Jeffreyssai had very carefully scribed himself, burning the concepts into his mind with each touch of the brush that wrote the words.  That which can be destroyed by the truth should be.  People can stand what is true, for they are already enduring it.  Curiosity seeks to annihilate itself.  Even one small plaque that showed nothing except a red horizontal slash.  Symbols could be made to stand for anything; a flexibility of visual power that even the Bardic Conspiracy would balk at admitting outright.

Beneath the plaques, two sets of tally marks scratched into the wall.  Under the plus column, two marks.  Under the minus column, five marks.  Seven times he had entered this room; five times he had decided not to change his mind; twice he had exited something of a different person.  There was no set ratio prescribed, or set range—that would have been a mockery indeed.  But if there were no marks in the plus column after a while, you might as well admit that there was no point in having the room, since you didn't have the ability it stood for.  Either that, or you'd been born knowing the truth and right of everything.

Jeffreyssai seated himself, not facing the plaques, but facing away from them, at the featureless white wall.  It was better to have no visual distractions.

In his mind, he rehearsed first the meta-mnemonic, and then the various sub-mnemonics referenced, for the seven major principles and sixty-two specific techniques that were most likely to prove needful in the Ritual Of Changing One's Mind.  To this, Jeffreyssai added another mnemonic, reminding himself of his own fourteen most embarrassing oversights.

He did not take a deep breath.  Regular breathing was best.

And then he asked himself the question.