Harry Potter and the Methods of Rationality

by Eliezer Yudkowsky

  Six incantations the Defense Professor spoke then; six of the thirty that he had used to safeguard their important conversations in Mary's Room.

  Harry raised his eyebrows, silently quizzical.

  "That is all I can manage for now," said the Defense Professor. "I expect it shall prove sufficient. Still, there is a proverb: If you do not wish a thing heard, do not say it. Consider it to apply in full measure. I am told that you were trying to see me?"

  "Yes," Harry said. He paused, gathered his thoughts. "Did the Headmaster, or anyone, tell you that we can't go to lunch any more?"

  "Something along those lines," said the Defense Professor. And without changing expression, "Of course I was terribly sorry to hear it."

  "It's more extreme than that, actually," said Harry. "I'm confined to Hogwarts and its grounds indefinitely. I can't leave without a guard and a good reason. I'm not going home for summer, and maybe not ever again. I was hoping... to speak with you, about that."

  There was a pause.

  The Defense Professor exhaled a breath like a brief sigh, and said, "We shall just have to rely on the known fact that the Deputy Headmistress will personally murder anyone who tries to report me. Mr. Potter, I intend to keep this conversation on track so that we may conclude it quickly, is that understood?"

  Harry nodded, and -

  In the light of the single torch, shaded toward the reddish end of the optical spectrum, the snake's green scales were not very reflective, and the blue-and-white banding hardly more so. Dark seemed the snake, in that light. The eyes, which had seemed like gray pits before, now reflected the torchlight, and seemed brighter than the rest of the snake.

  "Sso," hissed the venomous creature. "What did you wissh to ssay?"

  And Harry hissed, "Sschoolmasster thinkss that woman'ss former Lord iss the one who sstole her from prisson."

  Harry had thought about it this time, and carefully, before he had decided that he would reveal to Professor Quirrell only that the Headmaster believed that; and not say anything about the prophecy which had set Voldemort on Harry's parents, nor that the Headmaster was reconstituting the Order of the Phoenix... it was a risk, a significant risk, but Harry needed an ally in this.

  "He believess that one iss alive?" the snake finally said. The divided, two-pronged tongue flickered rapidly from side to side, sardonic snakish laughter. "Ssomehow I am not ssurprissed."

  "Yess," Harry hissed dryly, "very amussing, I am ssure. Except now am sstuck in Hogwartss for next ssix years, for ssafety! I have decided that I will, indeed, sseek power; and confinement iss not helpful for that. Musst convince sschoolmasster that Dark Lord iss not yet awakened, that esscape was work of ssome other power -"

  Again the rapid flickering of the snake's tongue; the snakish laughter was stronger, dryer, this time. "Amateur foolisshnesss."

  "Pardon?" hissed Harry.

  "You ssee misstake, think of undoing, ssetting time back to sstart. Yet not even with hourglasss can time be undone. Musst move forward insstead. You think of convincing otherss they are misstaken. Far eassier to convince them they are right. Sso conssider, boy: what new happensstance would make schoolmasster decide you were ssafe once more, ssimultaneoussly advance your other agendass?"

  Harry stared at the snake, puzzled. His mind tried to comprehend and unravel the riddle -

  "Iss it not obviouss?" hissed the snake. Again the tongue flickered sardonic laughter. "To free yoursself, to gain power in Britain, you musst again be sseen to defeat the Dark Lord."

  In reddish-orange flickering torchlight, a green snake swayed above a white hospital bed, as the boy stared into the embers of its eyes.

  "Sso," Harry said finally. "Let uss be clear on what iss propossed. You ssuggesst that we sset up imposstor to imperssonate Dark Lord."

  "Ssomething like that. Woman we resscued will cooperate, sshould be mosst convincing when sshe iss sseen at hiss sside." More sardonic tongue-flickering. "You are kidnapped from Hogwartss to public location, many witnesssess, wardss keep out protectorss. Dark Lord announcess that he hass at long lasst regained physical form, after wandering as sspirit for yearss; ssayss that he hass gained sstill greater power, not even you can sstop him now. Offerss to let you duel. You casst guardian Charm, Dark Lord laughss at you, ssayss he iss not life-eater. Casstss Killing Cursse at you, you block, watcherss ssee Dark Lord explode -"

  "Casst Killing Cursse?" Harry hissed in incredulity. "At me? Again? Ssecond time? Nobody will believe Dark Lord could posssibly be that sstupid -"

  "You and I are only two people in country who would notice that," hissed the snake. "Trusst me on thiss, boy."

  "What if there iss third, ssomeday?"

  The snake swayed thoughtfully. "Could write different sscript for play, if you wissh. Whatever sscenario, sshould leave open posssibility Dark Lord might return yet again - nation musst think they are sstill dependent on you to protect them."

  Harry stared into the red-flickering pits of the snake's eyes.

  "Well?" hissed the swaying form.

  The obvious thought was that going along with the Defense Professor's plots and deceptions a second time, spinning an even more complicated lie to cover up the first mistake, and creating another fatal vulnerability if anyone ever discovered the truth, would be exactly the same sort of stupidity as the putative Dark Lord using the Killing Curse again. It didn't even take his Hufflepuff side to point that out, Harry thought it in his very own mental voice.

  But there was also a certain question as to whether the appropriate moral to learn from the last experience was to always say no immediately to the Defense Professor, or...

  "Will think about it," hissed Harry. "Will not ansswer right away, thiss time, will enumerate risskss and benefitss firsst -"

  "Undersstood," hissed the snake. "But remember thiss, boy, other eventss proceed without you. Hessitation iss alwayss eassy, rarely usseful."

  The boy emerged from the private room into the main infirmary, running nervous fingers through his messy black hair as he walked past the white beds, occupied and unoccupied.

  Shortly afterward, the boy emerged from the Hogwarts infirmary entirely, passing Madam Pomfrey on the way out with a distracted nod.

  The boy walked out into a hallway, then into a larger corridor, and then stopped and leaned against the wall.

  The thing was...

  ...he really didn't want to be stuck in Hogwarts for the next six years; and when you thought about it...

  ... the Incident with Rescuing Bellatrix From Azkaban wasn't just imposing costs on Harry. Other people would be worrying, living in fear of the Dark Lord's return, expending unknown resources to take unknown precautions. Harry could demand that they write the script in such fashion as to make it seem not plausible that the Dark Lord would return a third time. And then people would relax, it would all be over.

  Unless of course there actually was a Dark Lord out there to be feared. There had been a prophecy.

  The boy leaning against the wall vented a soft sigh, and started walking again.

  Harry had almost forgotten, but he had gotten around to showing Professor Quirrell the deck of cards he'd been given on Sunday night by 'Santa Claus', within which the King of Hearts was allegedly a portkey that would take him to the Salem Witches' Institute in America. Although of course Harry hadn't told Professor Quirrell who'd sent him the card, nor what it was supposed to do, before he'd asked Professor Quirrell if it was possible to tell where the portkey would send him.

  The Defense Professor had transformed back to human form, and examined the King of Hearts, tapping it a few times with his wand.

  And according to Professor Quirrell...

  ...the portkey would send the user somewhere in London, but he couldn't pinpoint it any nearer than that.

  Harry had shown Professor Quirrell the note that had accompanied the deck of cards, saying nothing of the earlier notes.

  Professor Quirrell had taken it in at a glance, given a dry chuckle, and observe
d that if you read the note carefully, it did not explicitly say that the portkey would take him to the Salem Witches' Institute.

  You needed to learn to pay attention to that kind of subtlety, Professor Quirrell said, if you wanted to be a powerful wizard when you grew up; or, indeed, if you wanted to grow up at all.

  The boy sighed again as he trudged off to class.

  He was starting to wonder if all the other wizarding schools were also like this, or if it was only Hogwarts that had a problem.

  Chapter 66: Self Actualization, Pt 1

  Hessitation iss alwayss eassy, rarely usseful.

  So the Defense Professor had told him; and while you could quibble about the details of the proverb, Harry understood the weaknesses of Ravenclaws well enough to know that you had to try answering your own quibbles. Did some plans call for waiting? Yes, many plans called for delayed action; but that was not the same as hesitating to choose. Not delaying because you knew the right moment to do what was necessary, but delaying because you couldn't make up your mind - there was no cunning plan which called for that.

  Did you sometimes need more information to choose? Yes, but that could also turn into an excuse for delaying; and it would be tempting to delay, when you were faced with a choice between two painful alternatives, and not choosing would avoid the mental pain for a time. So you would pick a piece of information you couldn't easily obtain, and claim that you couldn't possibly decide without it; that would be your excuse. Although if you knew what information you needed, knew when and how you would obtain that information, and knew what you would do depending on each possible observation, then that was less suspicious as an excuse for hesitating.

  If you weren't just hesitating, you ought to be able to choose in advance what you would do, once you had the extra information you claimed you needed.

  If the Dark Lord were really out there, would it be smart to go along with Professor Quirrell's plan to have someone impersonate the Dark Lord?

  No. Definitely no. Absolutely not.

  And if Harry knew for a fact that the Dark Lord wasn't really out there... in that case...

  The Defense Professor's office was a small room, at least today; it had changed since the last time Harry had seen it, the stone of the room becoming darker, more polished. Behind the Defense Professor's desk stood the single empty bookcase that always decorated the room, a tall bookcase stretching almost from the floor to the ceiling, with seven empty wooden shelves. Harry had only once seen Professor Quirrell take a book from those empty shelves, and never seen him put a book back.

  The green snake swayed above the seat of the chair behind the Defense Professor's desk, the lidless eyes staring unblinking at Harry from close to his own eye level.

  They were warded now by twenty-two spells, all that could be cast within Hogwarts without attracting the Headmaster's attention.

  "No," hissed Harry.

  The green snake cocked its head, tilting it slightly; no emotion was conveyed by the gesture, not that Harry's Parselmouth talent conveyed to him. "Reasson not?" said the green snake.

  "Too rissky," Harry said simply. That was true whether or not the Dark Lord was out there. Forcing himself to decide in advance had made him realize that he'd just been using the unanswered question as an excuse to hesitate; the sane decision was the same, either way.

  For a moment the dark pitted eyes seemed to gleam blackly, for a moment the scaled mouth gaped to expose the fangs. "Think you have learned wrong lessson, boy, from previouss failure. My planss are not in habit of failing, and lasst one would have gone flawlesssly, but for your own foolisshnesss. Correct lessson iss to follow ssteps laid down for you by older and wisser Sslytherin, tame your wild impulssess."

  "Lessson I learned is not to try plotss that would make girl-child friend think I am evil or boy-child friend think I am sstupid," Harry snapped back. He'd been planning a more temporizing response than that, but somehow the words had just slipped out.

  The sssss-ing sound that came from the snake was not heard by Harry as words, only as pure fury. A moment later, "You told them -"

  "Of coursse not! But know what they would ssay."

  There was a long pause as the snake-head swayed, staring at Harry; again no detectable emotion came through, and Harry wondered what Professor Quirrell could be thinking that would take Professor Quirrell that long to think.

  "You sserioussly care what thosse two think?" came the snake's final hiss. "True younglingss thosse two are, not like you. Could not weigh adult matterss."

  "Might have done better than me," Harry hissed. "Boy-child friend would have assked after ssecret motivess before asssenting to resscue woman -"

  "Glad you undersstand that now," the snake hissed coldly. "Alwayss assk after other'ss advantage. Next learn to alwayss assk after your own. If my plan iss not to your tasste, what iss yours?"

  "If necesssary - sstay at sschool ssix yearss and sstudy. Hogwartss sseemss fine place to dwell. Bookss, friendss, sstrange but tassty food." Harry wanted to chuckle, but there wasn't any gesture in Parseltongue for the kind of laughter he wanted to express.

  The pits of the snake's eyes seemed almost black. "Eassy to ssay that now. Ssuch as you and I, we do not tolerate imprissonment. You will losse patience long before sseventh year, perhapss before end of thiss one. I sshall plan accordingly."

  And before Harry could hiss another word of Parseltongue, the human-shape of Professor Quirrell was sitting in his chair once more. "So, Mr. Potter," said the Defense Professor, his voice as calm as if they had been discussing nothing important, as if the whole conversation had not occurred at all, "I hear that you have begun to practice dueling. Not the worthless sort with rules, I hope?"

  Hannah Abbott looked as unnerved as Hermione had ever seen her (except on the day of the phoenix, the day Bellatrix Black had escaped, which shouldn't ought to count for anyone). The Hufflepuff girl had come over to the Ravenclaw table during dinner, and tapped Hermione on her shoulder, and very nearly dragged her away -

  "Neville and Harry Potter are learning dueling from Mr. Diggory!" Hannah blurted as soon as they were a few steps away from the table.

  "Who?" said Hermione.

  "Cedric Diggory!" said Hannah. "He's the Captain of our Quidditch Team, and general of an army, and he's taking all the electives and getting better grades than anyone, and I hear he learns dueling from professional tutors during the summers, and he once beat two seventh-year students, and even some teachers call him the Super Hufflepuff, and Professor Sprout says we should all emu, uh, emudate him or something like that, and -"

  After Hannah finally stopped for air (the list had gone on for a while), Hermione managed to insert a word in edgewise.

  "Sunshine Soldier Abbott!" said Hermione. "Calm down. We're not going to be fighting General Diggory, right? Sure, Neville's studying to beat us, but we can study too -"

  "Don't you see?" Hannah shrieked, raising her voice a lot louder then it should've been, if they were trying to keep the conversation private from all the Ravenclaws looking at them. "Neville isn't studying to beat us! He's practicing so he can fight Bellatrix Black! They're going to go through us like a Bludger through a stack of pancakes!"

  The Sunshine General gave her soldier a look. "Listen," said Hermione, "I don't think a few weeks of practice is going to make anyone an invincible fighter. Plus we already know how to handle invincible fighters. We'll concentrate fire on them and they'll go down just like Draco."

  The Hufflepuff girl was looking at her with mixed admiration and skepticism. "Aren't you even, you know, worried?"

  "Oh, honestly!" said Hermione. Sometimes it was hard being the only sensible person in your whole school year. "Haven't you ever heard the saying, the only thing we have to fear is fear itself?"

  "What?" said Hannah. "That's crazy, what about Lethifolds lurking in the darkness, and being put under the Imperius Curse, and horrible Transfiguration accidents and -"

  "I mean," said Hermione, exasperation leaki
ng out into her now-raised voice, she'd been hearing this sort of thing all week now, "how about if we wait until after the Chaos Legion actually crushes us to get so scared of them and did you just mutter 'Gryffindors' under your voice?"

  A few moments later, Hermione was walking back to her place at the table with a sweet smile plastered onto her young face, it wasn't the terrible cold glare of Harry's dark side but it was the scariest face she knew how to make.

  Harry Potter was going down.

  "This is loony," gasped Neville, with what tiny amount of breath he could spare from being completely out of breath.

  "This is brilliant!" said Cedric Diggory. The eyes of the Super Hufflepuff gleamed with manic enthusiasm, shining like the sweat on his forehead as he stamped his feet through the dance of one of his dueling postures. His usually-light steps had changed to heavier stomps, which might have had something to do with the Transfigured metal weights they'd all attached to their arms and legs and strapped over their chests. "Where do you get these ideas, Mr. Potter?"

  "A strange old shop... in Oxford... and I'm never... shopping there... again." Thud.

  Chapter 67: Self Actualization, Pt 2

  In the high reaches of Hogwarts where rooms and corridors changed on a daily basis, where the territory itself was uncertain and not just the map, where the stability of the castle began to fray into dreams and chaos without changing its architectural style or apparent solidity - in the high reaches of Hogwarts, a battle would soon be fought.

  The presence of so many students would stabilize the corridors for a time, by dint of constant observation. The rooms and corridors of Hogwarts sometimes moved even while people looked directly at them, but they wouldn't change. Even after eight centuries, Hogwarts was still a little shy about changing in front of people.

  But despite that transient permanence (the Defense Professor had said) the upper reaches of Hogwarts still had a military realism: you had to learn the ground anew each time, and check every closet for secret corridors all over again.