Harry Potter and the Methods of Rationality

by Eliezer Yudkowsky

  THE VILLAGE HIDDEN IN THE CLARITY

  "Consider the computational power required to manifest over a hundred shadow clones," the Uchiha genius said in his dispassionate tones. "It is an error of rationality, Sakura, to say 'fluke' and think you have explained anything. 'Fluke' is simply the name one gives to data that one is ignoring."

  "But it has to be a fluke!" Sakura yelled. With effort, she calmed her voice into the careful precision expected of a rationality ninja; it wouldn't do to have her crush think she was stupid. "Like you said, the computational power required to use over a hundred Kage Bunshin is simply absurd. We're talking the level of a major superintelligence. Naruto's the dead last of our class. He's not even jounin-level smart, let alone a superintelligence!"

  The Uchiha's eyes gleamed, almost as though he had activated his Smartingan. "Naruto can manifest a hundred independently acting clones. He must have the raw brainpower. But, under ordinary circumstances, something prevents him from using this computational power efficiently... like a mind at war within itself, perhaps? We now have cause to believe that Naruto is in some way connected to a superintelligence, and as a recently graduated genin, he, like us, is fifteen years old. What happened fifteen years ago, Sakura?"

  It took a moment for Sakura to comprehend, to remember, and then she understood.

  The attack of the Nine-Brains Demon Fox.

  Just a small bone-white creature with big ears and bigger tail and beady red eyes. It was no stronger than an ordinary fox, it didn't breathe fire or flash laser eyes, it possessed no chakra and no magic of any kind, but its intelligence was over nine thousand times that of a human being.

  Hundreds had been killed, half the buildings wrecked, almost the whole village of Beisugakure had been destroyed.

  "You think the Kyubey is hiding inside Naruto?" Sakura said. A moment later, her brain automatically went on to fill in the obvious implications of the theory. "And the software conflict between their existences is why he acts like a gibbering idiot half the time, but can control a hundred Kage Bunshin. Huh. That makes... a lot of sense... actually..."

  Sasuke gave her the brief, contemptuous nod of someone who had figured all this out on his own, without anyone else needing to prompt him.

  "Ano..." said Sakura. Only years of sanity exercises channeled her complete screaming panic into pragmatically useful policy options. "Shouldn't we... tell someone about this? Like, sometime in the next five seconds?"

  "The adults already know," Sasuke said emotionlessly. "It is the obvious explanation for their treatment of Naruto. No, the real question is how this fits into the outwitting of the Uchiha..."

  "I don't see how it fits at all -" began Sakura.

  "It must fit!" A tinge of frantic emotion flickered in Sasuke's voice. "I asked that man why he did it, and he told me that when I knew the answer to that, it would explain everything! Surely this must also be part of what is to be explained!"

  Sakura sighed to herself. Her personal hypothesis was that Itachi had just been trying to drive his brother into clinical paranoia.

  "Yo, kids," said the voice of their rationality sensei from their radio earpieces. "There's a village in Wave trying to build a bridge, and it keeps falling down for no reason anyone can figure out. Meet up at the gates at noon. It's time for your first C-ranked analysis mission."

  ERDŐS IN CHAINS

  "How could you do it, Anita?" said Richard, his voice very tight. "How could you coauthor a paper with Jean-Claude? You study the undead, you don't collaborate with them on papers!"

  "And what about you?" I spat. "You coauthored a paper with Sylvie! It's all right for you to be prolific but not me?"

  "I'm the head of her institute," Richard growled. I could feel the waves of science radiating off him; he was angry. "I have to work with Sylvie, it doesn't mean anything! I thought our own research was special, Anita!"

  "It is," I said, feeling helpless about my inability to explain things to Richard. He didn't understand the thrill of being a polymath, the new worlds that were opening up to me. "I didn't share our research with anyone -"

  "But you wanted to," said Richard.

  I didn't say anything, but I knew that the look on my face said it all.

  "God, Anita, you've changed," said Richard. He seemed to slump in on himself. "Do you realize that the monsters are joking about Blake numbers, now? I used to be your partner in everything, and now - I'm just another werewolf with a Blake number of 1."

  THUNDERSMARTS

  "I am sick of this!" shouted Liono. "Sick of doing this every single week! Our species was capable of interstellar travel, Panthro, I know the quantities of energy involved! There is no way you can't build a nuke or steer an asteroid or somehow blow up that ever-living idiot's pyramid!"

  HE-MAN AND THE MASTERS OF RATIONALITY

  "Fabulous secret knowledge was revealed to me on the day I held aloft my magic book and said: By the power of Bayes's Theorem!"

  FATE/SANE NIGHT

  I am the core of my thoughts

  Belief is my body

  And choice is my blood

  I have revised over a thousand judgments

  Unafraid of loss

  Nor aware of gain

  Have withstood pain to update many times

  Waiting for truth's arrival.

  This is the one uncertain path.

  My whole life has been...

  Unlimited Bayes Works!

  THE NAME OF THE RATIONALITY

  The eleven-year-old boy who would someday become legend - slayer of dragons, killer of kings - had but one thought upon his mind, as he approached the Sorting Hat to enter into the study of mysteries.

  Anywhere but Ravenclaw anywhere but Ravenclaw oh please anywhere but Ravenclaw...

  But no sooner the brim of the ancient felted device slipped over his forehead -

  "RAVENCLAW!"

  As the table decked in blue began to applaud him, as he approached the dread table where he would spend the next seven years, Kvothe was already wincing inside, waiting for the inevitable; and the inevitable happened almost at once, exactly as he had feared it, before he'd even had a chance to sit down properly.

  "So!" an older boy said with the happy expression of someone who's thought of something terribly clever. "Kvothe the Raven, huh?"

  TENGEN TOPPA GURREN RATIONALITY 40K

  I have a truly marvelous story for this crossover which this margin is too narrow to contain.

  UTILITARIAN TWILIGHT

  (Note: Written after I heard Alicorn was writing a Twilight fanfic, but before I read Luminosity. It's obvious if you're one of us.)

  "Edward," said Isabella tenderly. She reached up a hand and stroked his cold, sparkling cheek. "You don't have to protect me from anything. I've listed out all the upsides and all the downsides, assigned them consistent relative weights, and it's just really obvious that the benefits of becoming a vampire outweigh the drawbacks."

  "Bella," Edward said, and swallowed desperately. "Bella -"

  "Immortality. Perfect health. Awakening psychic powers. Easy enough to survive on animal blood once you do it. Even the beauty, Edward, there are people who would give their lives to be pretty, and don't you dare call them shallow until you've tried being ugly. Do you think I'm scared of the word 'vampire'? I'm tired of your arbitrary deontological constraints, Edward. The whole human species ought to be in on your fun, and people are dying by the thousands even as you hesitate."

  The gun in his lover's hand was cold against his forehead. It wouldn't kill him, but it would disable him for long enough -

  JASMINE AND THE LAMP

  Aladdin's face was wistful, but determined, as the newly minted street urchin addressed the blue being of cosmic power for one last time, prepared to leave behind the wealth and hope he had so briefly tasted for the sake of his friend. "Genie, I make my third wish. I wish for you to be -"

  Princess Jasmine, who had been staring at this with her mouth open, not quite believing what she was seeing
, just barely managed to overcome her paralysis and yank the lamp out of the boy's hand before he could finish the fatal sentence.

  "Excuse me," said Jasmine. "Aladdin, my darling, you're cute but you're an idiot, do you know that? Did you not notice how once Jafar got his hands on this lamp, he got his own three wishes - oh, never mind. Genie, I wish for everyone to always be young and healthy, I wish nobody ever had to die if they didn't want to, and I wish for everyone's intelligence to gradually increase at a rate of 1 IQ point per year." She tossed the lamp back to Aladdin. "Go back to what you were doing."

  RATIONALIST HAMLET

  (contributed by Histocrat on LiveJournal, post 13389, aka HonoreDB on LessWrong)

  (reposted with permission)

  HAMLET

  Interloper, abandon this strange prank,

  which makes cruel use of the blindness of my grief,

  and the good heart of my good friend Horatio.

  Or else, if thou hast true title to this belov'd form,

  tell me:

  What drawing did I present to Hamlet King,

  when six years old and scarce out of my sling?

  Ghost

  'twas a unicorn clad all in mail.

  HAMLET

  What.

  Ghost

  Mark me.

  HAMLET

  Father, I will.

  Ghost

  My hour is almost come,

  When I to sulphurous and tormenting flames

  Must render up myself.

  HAMLET

  Thou art in torment?

  Ghost

  Ay, as are all who die unshriven.

  HAMLET

  Like every Dane this is what I've been taught.

  Yet I did figure such caprice ill-suited to almighty God.

  For all who suffer unlook'd for deaths, unattended by God's chosen priests,

  to be then punish'd for the ill-ordering of the world...

  Ghost

  'twas not the world that killed me, nor accident of any kind.

  HAMLET

  What?

  Ghost

  If thou didst ever thy dear father love,

  Revenge his foul and most unnatural murder.

  HAMLET

  Oh God.

  Ghost

  My time grows ever shorter. Wilt thou hear the tale?

  HAMLET

  No.

  Ghost

  What?

  HAMLET

  My love for you does call me to avenge your death,

  but greater crimes have I heard told this night.

  If all those murdered go to Hell, and others as well,

  who would have confess'd had they the time,

  If people who are, in balance, good, suffer grisly

  at the hands of God, then I defy God's plan.

  Good Ghost, as one who dwells beyond the veil,

  you know things that we mortals scarce conceive.

  Tell me: is there some philter or device,

  outside nature's ken but not outside her means,

  by which death itself may be escap'd?

  Ghost

  You seek to evade Hell?

  HAMLET

  I seek to deny Hell to everyone!

  and Heaven too, for I suspect the Heaven of our mad God

  might be a paltry thing, next to the Heaven I will make of Earth,

  when I am its immortal king.

  Ghost

  I care not for these things.

  Death and hell have stripp'd away all of my desires,

  save for revenge upon my murderer.

  HAMLET

  Thou shalt not be avenged, save that thou swear:

  an I slay thine killer, so wilt thou vouchsafe to me the means

  by which I might slay death.

  He who killed you will join you in the Pit,

  and then that's it. No further swelling of Hell's ranks will I permit.

  Ghost

  Done. When my brother is slain, he who poured the poison in my ear,

  then will I pour in yours the precious truth:

  the making of the Philosopher's Stone. With this Stone, thou may'st procure

  a philter to render any man immune to death, and more transmute

  base metal to gold, to fund the provision of this philter to all mankind.

  HAMLET

  Truly there is nothing beyond the dreaming of philosophy.

  Wait.

  The man whom I must kill-my uncle the king?

  Ghost

  Ay, that incestuous, that adulterate beast,

  With witchcraft of his wit, with traitorous gifts-

  HAMLET

  Indeed, he has such gifts I near despair,

  of killing him and yet succeeding to his throne.

  'twill be an awesome fight for awesome stakes.

  Hast thou advice?

  A cock crows. Exit Ghost.

  (HonoreDB has now extended this to a complete ebook)

  (entitled "A Will Most Incorrect to Heaven: The Tragedy of Prince Hamlet and the Philosopher's Stone")

  (available for $3 at makefoil dot com)

  (yes, really)

  MOBY DICK AND THE METHODS OF RATIONALITY

  (as related by Eneasz on LessWrong)

  "Revenge?" said the peg-legged man. "On a whale? No, I decided I'd just get on with my life."

  ALICE IN THE LAND WHERE THINGS ARE EVEN CRAZIER THAN HERE

  (as first written by braindoll in a review of this chapter, with some further edits)

  Alice was sitting by her sister on the bank, reading a book. She had several friends who were older, and if she just asked nicely, they were often happy to lend her books without quite so many pictures and conversations as was thought appropriate for a girl her age.

  Hot days often made her feel sleepy and stupid, so Alice had thoughtfully wet a handkerchief and placed it at the back of her neck. Still her mind had gone off wandering (just as if it was some little kitten whose owner had taken off her eyes for just a moment), and she had just decided that the pleasure of making a daisy-chain would be worth around 4/3 of the trouble of getting up and picking the daisies, which was nonetheless not equal to the opportunity cost of putting down her book, when suddenly a White Rabbit with pink eyes ran close by her.

  There was nothing so very remarkable in that; nor, in fact, did Alice think it so very much out of the way to hear the Rabbit say to itself, "Oh dear! Oh dear! I shall be late!" But when the Rabbit actually took a watch out of its waistcoat- pocket, and looked at it, and then hurried on, Alice froze in sudden clarity and fear, for she had never before seen a rabbit with either a waistcoat-pocket, or a watch to take out of it. "Oh bother," she said to herself (though not aloud; she had long since cured herself of that habit, as it made people take her even less seriously than they already did). "If I did not immediately recognize how much curiouser that was than the average rabbit, then something is interfering with my curiosity, and that is most curious of all." So, burning with questions, she ran across the field after it, and was just in time to see it pop down a large rabbit-hole under the hedge.

  WELCOME TO THE REAL WORLD

  (thanks to dsummerstay for reminding me to post this one)

  MORPHEUS: For the longest time, I wouldn't believe it. But then I saw the fields with my own eyes, watched them liquefy the dead so they could be fed intravenously to the living -

  NEO (politely): Excuse me, please.

  MORPHEUS: Yes, Neo?

  NEO: I've kept quiet for as long as I could, but I feel a certain need to speak up at this point. The human body is the most inefficient source of energy you could possibly imagine. The efficiency of a power plant at converting thermal energy into electricity decreases as you run the turbines at lower temperatures. If you had any sort of food humans could eat, it would be more efficient to burn it in a furnace than feed it to humans. And now you're telling me that their food is the bodies of the dead, fed to the living? Haven't you ever heard of the laws of thermodyn
amics?

  MORPHEUS: Where did you hear about the laws of thermodynamics, Neo?

  NEO: Anyone who's made it past one science class in high school ought to know about the laws of thermodynamics!

  MORPHEUS: Where did you go to high school, Neo?

  (Pause.)

  NEO: ...in the Matrix.

  MORPHEUS: The machines tell elegant lies.

  (Pause.)

  NEO (in a small voice): Could I please have a real physics textbook?

  MORPHEUS: There is no such thing, Neo. The universe doesn't run on math.

  Chapter 65: Contagious Lies

  Hermione Granger had read somewhere once, that one of the keys to staying thin was to pay attention to the food you ate, to notice yourself eating it, so that you were satisfied with the meal. This morning she'd made herself toast, and put butter on the toast, and cinnamon on the butter, and it really should've been enough to get her to notice, this time, the goodness that was in front of her...