Eliezer Yudkowsky - Harry Potter and the Methods of Rationality

Harry had run into some stupid teachers during his abortive forays into standard Muggle education - his father had been a lot pickier when it came to selecting grad students as tutors, of course - but History class was the first time he'd encountered a teacher who literally wasn't sentient.

And it showed, too. Harry had given up after five minutes and started reading a textbook. When it became clear that "Professor Binns" wasn't going to object, Harry had also reached into his pouch and gotten earplugs.

Did ghosts not require a salary? Was that it? Or was it literally impossible to fire anyone in Hogwarts even if they died?

Now it seemed that Professor Snape was going about being absolutely awful to everyone who wasn't a Slytherin and it hadn't even occurred to anyone to terminate his contract.

And the Headmaster had set fire to a chicken.

"Excuse me," came a worried voice from behind him.

"I swear," Harry said without turning around, "this place is almost eight and a half percent as bad as what Dad says about Oxford."

Harry stamped down the stone corridors, looking affronted, annoyed, and infuriated all at once.

"Dungeons!" Harry hissed. " Dungeons! These are not dungeons! This is a basement! A basement! "

Some of the Ravenclaw girls gave him odd looks. The boys were all used to him by now.

It seemed that the level in which the Potions classroom was located was called the "dungeons" for no better reason than that it was below ground and slightly colder than the main castle.

In Hogwarts! In Hogwarts! Harry had been waiting his whole life and now he was still waiting and if there was anywhere on the face of the Earth that had decent dungeons it ought to be Hogwarts! Was Harry going to have to build his own castle if he wanted to see one little bottomless abyss?

A short time later they got to the actual Potions classroom and Harry cheered up considerably.

The Potions classroom had strange preserved creatures floating in huge jars on shelves that covered every centimeter of wall space between the closets. Harry had gotten far enough along in his reading now that he could actually identify some of the creatures, like the Zabriskan Fontema. Albeit the fifty-centimeter spider looked like an Acromantula but it was too small to be one. He'd tried asking Hermione, but she hadn't seemed very interested in looking anywhere near where he was pointing.

Harry was looking at a large dust ball with eyes and feet when the assassin swept into the room.

That was the first thought that crossed Harry's mind when he saw Professor Severus Snape. There was something quiet and deadly about the way the man stalked between the children's desks. His robes were unkempt, his hair spotted and greasy. There was something about him that seemed reminiscent of Lucius, although the two of them looked nothing remotely alike, and you got the impression that where Lucius would kill you with flawless elegance, this man would simply kill you.

"Sit down," said Professor Severus Snape. "Now."

Harry and a few other children who had been standing around talking to each other scrambled for desks. Harry had planned on ending up next to Hermione but somehow he found himself sitting down in the nearest empty desk next to Justin Finch-Fletchley (it was a Doubles session, Ravenclaw and Hufflepuff) which put him two desks to the left of Hermione.

Severus seated himself behind the teacher's desk, and without the slightest transition or introduction, said, "Hannah Abbott."

"Here," said Hannah in a somewhat trembling voice.

"Susan Bones."

"Present."

And so it went, no one daring to say a word in edgewise, until:

"Ah, yes. Harry Potter. Our new... celebrity. "

"The celebrity is present, sir ."

Half the class flinched, and some of the smarter ones suddenly looked like they wanted to run out the door while the classroom was still there.

Severus smiled in an anticipatory sort of way and called the next name on his list.

Harry gave a mental sigh. That had happened way too fast for him to do anything about it. Oh well. Clearly this man already didn't like him, for whatever reason. And when Harry thought about it, better by far that this Potions professor should pick on him rather than, say, Neville or Hermione. Harry was a lot better able to defend himself. Yep, probably all for the best.

When full attendance had been taken, Severus swept his gaze over the full class. His eyes were as empty as a night sky without stars.

"You are here," Severus said in a quiet voice which the students at back strained to hear, "to learn the subtle science and exact art of potionmaking. As there is little foolish wand-waving here, many of you will hardly believe this is magic. I don't expect you will really understand the beauty of the softly simmering cauldron with its shimmering fumes, the delicate power of liquids that creep through human veins," this in a rather caressing, gloating tone, "bewitching the mind, ensnaring the senses," this was just getting creepier and creepier. "I can teach you how to bottle fame, brew glory, even stopper death - if you aren't as great a pack of fools as I usually have to teach."

Severus somehow seemed to notice the look of skepticism on Harry's face, or at least his eyes suddenly jumped to where Harry was sitting.

"Potter!" snapped the Potions professor. "What would I get if I added powdered root of asphodel to an infusion of wormwood?"

Harry blinked. "Was that in Magical Drafts and Potions ?" he said. "I just finished reading it, and I don't remember anything which used wormwood -"

Hermione's hand went up and Harry shot her a glare which caused her to raise her hand even higher.

"Tut, tut," Severus said silkily. "Fame clearly isn't everything."

"Really?" Harry said. "But you just told us you'd teach us how to bottle fame. Say, how does that work, exactly? You drink it and turn into a celebrity?"

Three-quarters of the class flinched.

Hermione's hand was dropping slowly back down. Well, that wasn't surprising. She might be his rival, but she wasn't the sort of girl who would play along after it became clear that the professor was deliberately trying to humiliate him.

Harry was trying hard to keep control of his temper. The first rejoinder that had crossed his mind was 'Abracadabra'.

"Let's try again," said Severus. "Potter, where would you look if I told you to find me a bezoar?"

"That's not in the textbook either," Harry said, "but in one Muggle book I read that a trichinobezoar is a mass of solidified hair found in a human stomach, and Muggles used to believe it would cure any poison -"

"Wrong," Severus said. "A bezoar is found in the stomach of a goat, it is not made of hair, and it will cure most poisons but not all."

"I didn't say it would, I said that was what I read in one Muggle book -"

"No one here is interested in your pathetic Muggle books. Final try. What is the difference, Potter, between monksblood and wolfsbane?"

That did it.

"You know," Harry said icily, "in one of my quite fascinating Muggle books, they describe a study in which people managed to make themselves look very smart by asking questions about random facts that only they knew. Apparently the onlookers only noticed that the askers knew and the answerers didn't, and failed to adjust for the unfairness of the underlying game. So, Professor, can you tell me how many electrons are in the outermost orbital of a carbon atom?"

Severus's smile widened. "Four," he said. "It is a useless fact which no one should bother writing down, however. And for your information, Potter, asphodel and wormwood make a sleeping potion so powerful it is known as the Draught of Living Death. As for monkshood and wolfsbane, they are the same plant, which also goes by the name of aconite, as you would know if you had read One Thousand Magical Herbs and Fungi. Thought you didn't need to open the book before coming, eh, Potter? All the rest of you should be copying that down so that you will not be as ignorant as him." Severus paused, looking quite pleased with himself. "And that will be... five points? No, let us make it an even ten points from Ravenclaw for backchat."