Harry Potter and the Methods of Rationality

by Eliezer Yudkowsky

  There were no questions about his father accompanying him to the magical side of King's Cross Station. Dad had trouble just looking at Harry's trunk directly. Magic ran in families, and Michael Verres-Evans couldn't even walk.

  So instead his father just cleared his throat. "Good luck at school, Harry," he said. "Do you think I bought you enough books?"

  Harry had explained to his father about how he thought this might be his big chance to do something really revolutionary and important, and Professor Verres-Evans had nodded and dumped his extremely busy schedule for two solid days in order to go on the Greatest Secondhand Bookshop Raid Ever, which had covered four cities and produced thirty boxes of science books now sitting in the cavern level of Harry's trunk. Most of the books had gone for a pound or two, but some of them definitely hadn't, like the very latest Handbook of Chemistry and Physics or the complete 1972 set of the Encyclopaedia Britannica. His father had tried to block Harry off from seeing the till displays but Harry figured his father must have spent at least a thousand pounds. Harry had said to his father that he would pay him back as soon as he figured out how to convert wizarding gold into Muggle money, and his father had told him to go jump in a lake.

  And then his father had asked him: Do you think I bought you enough books? It was quite clear what answer Dad wanted to hear.

  Harry's throat was hoarse, for some reason. "You can never have enough books," he recited the Verres family motto, and his father knelt down and gave him a quick, firm embrace. "But you certainly tried," Harry said, and felt himself choking up again. "It was a really, really, really good try."

  His Dad straightened. "So..." he said. "Do you see a Platform Nine and Three-Quarters?"

  King's Cross Station was huge and busy, with walls and floors paved with ordinary dirt-stained tiles. It was full of ordinary people hurrying about their ordinary business, having ordinary conversations which generated lots and lots of ordinary noise. King's Cross Station had a Platform Nine (which they were standing on) and a Platform Ten (right nearby) but there was nothing between Platform Nine and Platform Ten except a thin, unpromising barrier wall. A great skylight overhead let in plenty of light to illuminate the total lack whatsoever of any Platform Nine and Three-Quarters.

  Harry stared around until his eyes watered, thinking, come on, mage-sight, come on, mage-sight, but absolutely nothing appeared to him. He thought about taking out his wand and waving it, but Professor McGonagall had warned him against using his wand. Plus if there was another shower of multicoloured sparks that might lead to being arrested for setting off fireworks inside a train station. And that was assuming his wand didn't decide to do something else, like blowing up all of King's Cross. Harry had only lightly skimmed his schoolbooks (though that skim was quite bizarre enough) in a very quick effort to determine what sort of science books to buy over the next 48 hours.

  Well, he had - Harry glanced at his watch - one whole hour to figure it out, since he was supposed to be on the train at eleven. Maybe this was the equivalent of an IQ test and the stupid kids couldn't become wizards. (And the amount of extra time you gave yourself would determine your Conscientiousness, which was the second most important factor in scholarly success.)

  "I'll figure it out," Harry said to his waiting parents. "It's probably some sort of test thingy."

  His father frowned. "Hm... maybe look for a trail of mixed footprints on the ground, leading somewhere that doesn't seem to make sense -"

  "Dad!" Harry said. "Stop that! I haven't even tried to figure it out on my own!" It was a very good suggestion, too, which was worse.

  "Sorry," his father apologised.

  "Ah..." Harry's mother said. "I don't think they would do that to a student, do you? Are you sure Professor McGonagall didn't tell you anything?"

  "Maybe she was distracted," Harry said without thinking.

  "Harry!" hissed his father and mother in unison. "What did you do?"

  "I, um -" Harry swallowed. "Look, we don't have time for this now -"

  "Harry!"

  "I mean it! We don't have time for this now! Because it's a really long story and I've got to figure out how to get to school!"

  His mother had a hand over her face. "How bad was it?"

  "I, ah," I can't talk about that for reasons of National Security, "about half as bad as the Incident with the Science Project?"

  "Harry!"

  "I, er, oh look there are some people with an owl I'll go ask them how to get in!" and Harry ran away from his parents towards the family of fiery redheads, his trunk automatically slithering behind him.

  The plump woman looked to him as he arrived. "Hello, dear. First time at Hogwarts? Ron's new, too -" and then she peered closely at him. "Harry Potter?"

  Four boys and a red-headed girl and an owl all swung around and then froze in place.

  "Oh, come on!" Harry protested. He'd been planning to go as Harry Verres at least until he got to Hogwarts. "I bought a sweatband and everything! How come you know who I am?"

  "Yes," Harry's father said, coming up behind him with long easy strides, "how do you know who he is?" His voice indicated a certain dread.

  "Your picture was in the newspapers," said one of two identical-looking twins.

  "HARRY!"

  "Dad! It's not like that! It's 'cause I defeated the Dark Lord You-Know-Who when I was one year old!"

  "WHAT?"

  "Mum can explain."

  "WHAT?"

  "Ah... Michael dear, there are certain things I thought it would be best not to bother you with until now -"

  "Excuse me," Harry said to the redheaded family who were all staring at him, "but it would be quite extremely helpful if you could tell me how to get to Platform Nine and Three Quarters right now."

  "Ah..." said the woman. She raised a hand and pointed at the wall between platforms. "Just walk straight at the barrier between platforms nine and ten. Don't stop and don't be scared you'll crash into it, that's very important. Best do it at a bit of a run if you're nervous."

  "And whatever you do, don't think of an elephant."

  "George! Ignore him, Harry dear, there's no reason not to think of an elephant."

  "I'm Fred, Mum, not George -"

  "Thanks!" Harry said and took off at a run towards the barrier -

  Wait a minute, it wouldn't work unless he believed in it?

  It was at times like this that Harry hated his mind for actually working fast enough to realise that this was a case where "resonant doubt" applied, that is, if he'd started out thinking that he would go through the barrier he'd have been fine, only now he was worried about whether he sufficiently believed he'd go through the barrier, which meant that he actually was worried about crashing into it -

  "Harry! Get back here, you have some explaining to do!" That was his Dad.

  Harry shut his eyes and ignored everything he knew about justified credibility and just tried to believe really hard that he'd go through the barrier and -

  - the sounds around him changed.

  Harry opened his eyes and stumbled to a halt, feeling vaguely dirtied by having made a deliberate effort to believe something.

  He was standing in a bright, open-air platform next to a single huge train, fourteen long carriages headed up by a massive scarlet-metal steam engine with a tall chimney that promised death to air quality. The platform was already lightly crowded (even though Harry was a full hour early); dozens of children and their parents swarmed around benches, tables, and various hawkers and stalls.

  It went entirely without saying that there was no such place in King's Cross Station and no room to hide it.

  Okay, so either (a) I just teleported somewhere else entirely (b) they can fold space like no one's business or (c) they are simply ignoring all the rules.

  There was a slithering sound behind him, and Harry turned around to observe that his trunk had indeed followed him on its small clawed tentacles. Apparently, for magical purposes, his luggage had also managed to believe with sufficie
nt strength to pass through the barrier. That was actually a little disturbing when Harry started thinking about it.

  A moment later, the youngest-looking red-haired boy came through the iron archway (iron archway?) at a run, pulling his trunk behind him on a lead and nearly crashing into Harry. Harry, feeling stupid for having stayed around, quickly began moving away from the landing area, and the red-haired boy followed him, yanking hard on his trunk's lead in order to keep up. A moment later, a white owl fluttered through the archway and came to rest on the boy's shoulder.

  "Cor," said the red-haired boy, "are you really Harry Potter?"

  Not this again. "I have no logical way of knowing that for certain. My parents raised me to believe that my name was Harry James Potter-Evans-Verres, and many people here have told me that I look like my parents, I mean my other parents, but," Harry frowned, realising, "for all I know, there could easily be spells to polymorph a child into a specified appearance -"

  "Er, what, mate?"

  Not headed for Ravenclaw, I take it. "Yes, I'm Harry Potter."

  "I'm Ron Weasley," said the tall skinny freckled long-nosed kid, and stuck out a hand, which Harry politely shook as they walked. The owl gave Harry an oddly measured and courteous hoot (actually more of an eehhhhh sound, which surprised Harry).

  At this point Harry realised the potential for imminent catastrophe. "Just a second," he said to Ron, and opened one of the drawers of his trunk, the one that if he recalled correctly was for Winter Clothes - it was - and then he found the lightest scarf he owned, underneath his winter coat. Harry took off his sweatband, and just as quickly unfolded the scarf and tied it around his face. It was a little hot, especially in the summer, but Harry could live with that.

  Then he shut that drawer and pulled out another drawer and drew forth black wizarding robes, which he shrugged over his head, now that he was out of Muggle territory.

  "There," Harry said. The sound came out slightly muffled through the scarf over his face. He turned to Ron. "How do I look? Stupid, I know, but am I identifiable as Harry Potter?"

  "Er," Ron said. He closed his mouth, which had been open. "Not really, Harry."

  "Very good," Harry said. "However, so as not to obviate the point of the whole exercise, you will henceforth address me as," Verres might not work anymore, "Mr. Spoo."

  "Okay, Harry," Ron said uncertainly.

  The Force is not particularly strong in this one. "Call... me... Mister... Spoo."

  "Okay, Mister Spoo -" Ron stopped. "I can't do that, it makes me feel stupid."

  That's not just a feeling. "Okay. You pick a name."

  "Mr. Cannon," Ron said at once. "For the Chudley Cannons."

  "Ah..." Harry knew he was going to terribly regret asking this. "Who or what are the Chudley Cannons?"

  "Who're the Chudley Cannons? Only the most brilliant team in the whole history of Quidditch! Sure, they finished at the bottom of the league last year, but -"

  "What's Quidditch?"

  Asking this was also a mistake.

  "So let me get this straight," Harry said as it seemed that Ron's explanation (with associated hand gestures) was winding down. "Catching the Snitch is worth one hundred and fifty points?"

  "Yeah -"

  "How many ten-point goals does one side usually score not counting the Snitch?"

  "Um, maybe fifteen or twenty in professional games -"

  "That's just wrong. That violates every possible rule of game design. Look, the rest of this game sounds like it might make sense, sort of, for a sport I mean, but you're basically saying that catching the Snitch overwhelms almost any ordinary point spread. The two Seekers are up there flying around looking for the Snitch and usually not interacting with anyone else, spotting the Snitch first is going to be mostly luck -"

  "It's not luck!" protested Ron. "You've got to keep your eyes moving in the right pattern -"

  "That's not interactive, there's no back-and-forth with the other player and how much fun is it to watch someone incredibly good at moving their eyes? And then whichever Seeker gets lucky swoops in and grabs the Snitch and makes everyone else's work moot. It's like someone took a real game and grafted on this pointless extra position so that you could be the Most Important Player without needing to really get involved or learn the rest of it. Who was the first Seeker, the King's idiot son who wanted to play Quidditch but couldn't understand the rules?" Actually, now that Harry thought about it, that seemed like a surprisingly good hypothesis. Put him on a broomstick and tell him to catch the shiny thing...

  Ron's face pulled into a scowl. "If you don't like Quidditch, you don't have to make fun of it!"

  "If you can't criticise, you can't optimise. I'm suggesting how to improve the game. And it's very simple. Get rid of the Snitch."

  "They won't change the game just 'cause you say so!"

  "I am the Boy-Who-Lived, you know. People will listen to me. And maybe if I can persuade them to change the game at Hogwarts, the innovation will spread."

  A look of absolute horror was spreading over Ron's face. "But, but if you get rid of the Snitch, how will anyone know when the game ends?"

  "Buy... a... clock. It would be a lot fairer than having the game sometimes end after ten minutes and sometimes not end for hours, and the schedule would be a lot more predictable for the spectators, too." Harry sighed. "Oh, stop giving me that look of absolute horror, I probably won't actually take the time to destroy this pathetic excuse for a national sport and remake it stronger and smarter in my own image. I've got way, way, way more important stuff to worry about." Harry looked thoughtful. "Then again, it wouldn't take much time to write up the Ninety-Five Theses of the Snitchless Reformation and nail it to a church door -"

  "Potter," drawled a young boy's voice, "what is that on your face and what is standing next to you?"

  Ron's look of horror was replaced by utter hatred. "You!"

  Harry turned his head; and indeed it was Draco Malfoy, who might have been forced to wear standard school robes, but was making up for that with a trunk looking at least as magical and far more elegant than Harry's own, decorated in silver and emeralds and bearing what Harry guessed to be the Malfoy family crest, a beautiful fanged serpent over crossed ivory wands.

  "Draco!" Harry said. "Er, or Malfoy if you prefer, though that kind of sounds like Lucius to me. I'm glad to see you're doing so well after, um, our last meeting. This is Ron Weasley. And I'm trying to go incognito, so call me, eh," Harry looked down at his robes, "Mister Black."

  "Harry!" hissed Ron. "You can't use that name!"

  Harry blinked. "Why not?" It sounded nicely dark, like an international man of mystery -

  "I'd say it's a fine name," said Draco, "but it belongs to the Noble and Most Ancient House of Black. I'll call you Mr. Silver."

  "You get away from... from Mr. Gold," Ron said coldly, and took a forward step. "He doesn't need to talk to the likes of you!"

  Harry raised a placating hand. "I'll go by Mr. Bronze, thanks for the naming schema. And, Ron, um," Harry struggled to find a way to say this, "I'm glad you're so... enthusiastic about protecting me, but I don't particularly mind talking to Draco -"

  This was apparently the last straw for Ron, who spun on Harry with eyes now aflame with outrage. "What? Do you know who this is?"

  "Yes, Ron," Harry said, "you may remember that I called him Draco without him needing to introduce himself."

  Draco sniggered. Then his eyes lit on the white owl on Ron's shoulder. "Oh, what's this?" Draco said in a drawl rich with malice. "Where's the famous Weasley family rat?"

  "Buried in the backyard," Ron said coldly.

  "Aw, how sad. Pot... ah, Mr. Bronze, I should mention that the Weasley family is widely agreed to have the best pet story ever. Want to tell it, Weasley?"

  Ron's face contorted. "You wouldn't think it was funny if it happened to your family!"

  "Oh," Draco purred, "but it wouldn't ever happen to the Malfoys."

  Ron's hands clenched into fists
-

  "That's enough," Harry said, putting as much quiet authority into the voice as he could manage. It was clear that whatever this was about, it was a painful memory for the red-haired kid. "If Ron doesn't want to talk about it, he doesn't have to talk about it, and I'd ask that you not talk about it either."

  Draco turned a surprised look on Harry, and Ron nodded. "That's right, Harry! I mean Mr. Bronze! You see what kind of person he is? Now tell him to go away!"

  Harry counted to ten inside his head, which for him was a very quick 12345678910 - an odd habit left over from the age of five when his mother had first instructed him to do it, and Harry had reasoned that his way was faster and ought to be just as effective. "I'm not telling him to go away," Harry said calmly. "He's welcome to talk to me if he wants."

  "Well, I don't intend to hang around with anyone who hangs around with Draco Malfoy," Ron announced coldly.

  Harry shrugged. "That's up to you. I don't intend to let anyone say who I can and can't hang around with." Silently chanting, please go away, please go away...

  Ron's face went blank with surprise, like he'd actually expected that line to work. Then Ron spun about, yanked his luggage's lead and stormed off down the platform.

  "If you didn't like him," Draco said curiously, "why didn't you just walk away?"

  "Um... his mother helped me figure out how to get to this platform from the King's Cross Station, so it was kind of hard to tell him to get lost. And it's not that I hate this Ron guy," Harry said, "I just, just..." Harry searched for words.

  "Don't see any reason for him to exist?" offered Draco.

  "Pretty much."

  "Anyway, Potter... if you really were raised by Muggles -" Draco paused here, as if waiting for a denial, but Harry didn't say anything "- then you mightn't know what it's like to be famous. People want to take up all of our time. You have to learn to say no."

  Harry nodded, putting a thoughtful look on his face. "That sounds like good advice."

  "If you try to be nice, you just end up spending the most time with the pushiest ones. Decide who you want to spend time with and make everyone else leave. You're just getting here, Potter, so everyone's going to judge you by who they see you with, and you don't want to be seen with the likes of Ron Weasley."