Eliezer Yudkowsky - Harry Potter and the Methods of Rationality

"Maybe it's You-Know-Who and maybe it isn't," Harry said, his voice sounding a little unsteady. "Let's not narrow down the hypothesis space prematurely." Harry took a breath and lowered his hands. "The other thing we can try is to nail the real culprit before the trial - or at least find solid evidence that someone else did it."

"Mr. Potter," said Minerva, "Professor Quirrell told the Aurors that he knew of someone with a motive to harm Mr. Malfoy. Do you know who he was talking about?"

"Yes," Harry said, after a hesitation. "But I think I shall conduct that part of my investigation with the Defense Professor - just as I would not have Professor Quirrell in the room while we were discussing how to investigate him. "

"He suspects me?" Severus said, then gave a short laugh. "Why, of course he does."

"My own plan," said Harry, "is to go look at the trophy room where the supposed duel took place and see if I can discover anything anomalous. If you can tell the investigating Aurors to let me through -"

"What investigating Aurors?" Severus said tonelessly.

Harry Potter took a deep breath, slowly let it out, and then spoke again. "In mystery books it usually takes longer than one day to solve a crime, but twenty-four hours is - no, thirty hours is eighteen hundred minutes. And I can think of at least one other important place to look for clues - though it'll have to be someone who can get into the Ravenclaw girls' dorm. Back when Hermione was fighting bullies, she was finding notes under her pillow each morning, telling her where to go -"

" Albus... " ground out Minerva.

"I did not send them," said the old wizard. His white eyebrows had lifted in surprise. "I knew nothing of this. You think she was being played, Harry?"

"It's a possibility," Harry said. "More so, because there's a part of this puzzle that you don't know about yet." Harry's voice lowered, grew more intense. "Headmaster, you already know that I got my father's invisibility cloak from someone who left a note under my pillow, saying it was an early Christmas present. I think we have to assume that's the same person who left notes for Hermione -"

"Harry," the old wizard said, and hesitated momentarily. "Returning your father's cloak to you, does not seem to me like the act of a villain -"

" Listen ," Harry Potter said urgently. "The part you don't know is that after Bellatrix Black escaped from Azkaban, I found another note under my pillow, signed 'Santa Claus', saying that they'd heard you were shutting me up inside Hogwarts, and that they were giving me an escape route to the Salem Witches' Institute in America. That note came with a deck of cards, in which the King of Hearts was supposedly a portkey -"

" Mr. Potter! " cried Professor McGonagall, she hadn't even thought before she spoke. "That could well be a kidnapping attempt! You should have told - "

" Yes , Professor, I did the sensible thing," the boy said levelly. "As adapted to the circumstances , I did the sensible thing. I told Professor Quirrell. And according to Professor Quirrell, that portkey goes to somewhere in London - it's definitely not strong enough to be an international portkey. Now it's possible that the person who sent the note is honest, and that the point in London is just a way station." The boy reached into his robes and took out a deck of cards, along with a folded paper note. "I will trust you not to go in guns blazing - I mean wands blazing - just in case the sender is an ally of mine, if not yours. But if this is a trap, I say we spring it now . And whoever it is, take them alive so we can exhibit them before the Wizengamot, I cannot overemphasize that part."

Severus rose from his chair, his eyes now intent, and moved toward Harry. "I'll need a hair of yours for Polyjuice, Mr. Potter -"

"Let us not be hasty!" said Albus. "We have not yet examined the notes sent to Miss Granger; there may be no resemblance after all. Severus, would you enter her dorm room and see if you can find those?"

Harry Potter's eyebrows had raised, even as he stood to offer the Potions Master better access to his mess of hair. "You think two different people are running around Hogwarts leaving notes beneath pillows?"

Severus gave a brief sardonic laugh, as his hand moved forward and plucked a hair, which soon was being carefully wrapped in silk. "Quite possibly. If I have learned anything in my tenure as Head of Slytherin, I have learned what ridiculous messes arise when there is more than one plotter and more than one plan. But Headmaster - I think Mr. Potter is correct that I should follow this portkey and see where it leads."

Albus hesitated, and then nodded reluctantly. "I will speak to you before you go, then."

Even as Harry Potter left the room for his own investigations, Severus spun on his heel and strode swiftly toward the jar of Floo powder, his cloak rising behind him with his speed. "I'll get some raw Polyjuice, add the hair, and go. Headmaster, will you stand by to -"

"Albus," Minerva said, surprised at how steady her own voice was, "did you leave those notes under Mr. Potter's pillow?"

Severus's hand halted an instant before casting Floo powder into the fire.

Dumbledore nodded to her, though the accompanying smile seemed a bit hollow. "You know me far too well, my dear."

"And I suppose the portkey goes to a friendly home where Mr. Potter would be kept safe and sound until you arrived to pick him up and return him to Hogwarts?" Her voice tight - it was sensible, she could not deny it was sensible, but somehow it seemed a little cruel.

"It would depend on the circumstances," the old wizard said quietly. "If Harry had gone so far - I might have let him make good his escape, for a time. Better to know where he was going, and ensure it was somewhere safe, with friends -"

"And to think," said Professor McGonagall, "that I had thought to reprimand Mr. Potter for not telling us about this important matter! Upbraid him for not having the sense to trust us!" Her voice had risen in volume. "I shall skip that lecture, I suppose!"

Severus was gazing at the Headmaster with narrowed eyes. "And the notes to Miss Granger -"

"The Defense Professor, very likely," the old wizard said. "Still - that is only a guess."

"I shall go look for them," Severus said. "And then, I suppose, start looking for You-Know-Who." A frown crossed the Potions Master's face. "A task at which I haven't the faintest idea of where to start. Do you know of any magics to find a soul, Headmaster?"

The Divination classroom was lit by the dim red light of a hundred small fires where burned a hundred kinds of incense, so that if you were to ask in one word what the room looked like, the answer would be 'smoke'. (Assuming you bothered to look at anything, when your nose was threatening to overload and die.) If your gaze could pierce those dank mists, you would see a tiny, cluttered room in which forty stuffed armchairs, most of them unused, were crammed around a small open space in the center of the room, where a circular trapdoor waited on your escape.

"The grim!" Professor Trelawney said in a quavering voice, as she peered into George Weasley's teacup. "The grim! It is a sign of death! One whom you know, George - someone you know is to die! And soon - yes, it shall be quite soon, I think - unless of course it is later -"

It would have been a good deal scarier, thought Fred and George, if she hadn't said the same thing to every single other student in their Divination class. They were hardly even thinking about it at this point; all their thoughts were on today's disaster -

The trapdoor in the floor flew open with a bang that caused Professor Trelawney to shriek and spill George's tea all over his robes, and then an instant later Dumbledore was whooshing up out of the floor with a bird of fire upon his shoulder.