Harry Potter and the Methods of Rationality

"I mean, if you've been dealing with idiots and want someone sane to talk to..."

There was a surprisingly long pause.

Professor Quirrell slammed the book shut and it vanished with a small whispering sound. He looked up, then, and Harry flinched.

"I suppose an intelligent conversation would be pleasant for me at this point," said Professor Quirrell in the same biting tone that had invited Harry to enter. "You are not likely to find it so, be warned."

Harry drew a deep breath. "I promise I won't mind if you snap at me. What happened?"

The cold in the room seemed to deepen. "A sixth-year Gryffindor cast a curse at one of my more promising students, a sixth-year Slytherin."

Harry swallowed. "What... sort of curse?"

And the fury on Professor Quirrell's face was no longer contained. "Why bother to ask an unimportant question like that, Mr. Potter? Our friend the sixth-year Gryffindor did not think it was important!"

"Are you serious?" Harry said before he could stop himself.

"No, I'm in a terrible mood today for no particular reason. Yes I'm serious, you fool! He didn't know. He actually didn't know. I didn't believe it until the Aurors confirmed it under Veritaserum. He is in his sixth year at Hogwarts and he cast a high-level Dark curse without knowing what it did."

"You don't mean," Harry said, "that he was mistaken about what it did, that he somehow read the wrong spell description -"

"All he knew was that it was meant to be directed at an enemy. He knew that was all he knew."

And that had been enough to cast the spell. "I do not understand how anything with that small a brain could walk upright."

"Indeed, Mr. Potter," said Professor Quirrell.

There was a pause. Professor Quirrell leaned forward and picked up the silver inkwell from his desk, turning it around in his hands, staring at it as though wondering how he could go about torturing an inkwell to death.

"Was the sixth-year Slytherin seriously hurt?" said Harry.

"Yes."

"Was the sixth-year Gryffindor raised by Muggles?"

"Yes."

"Is Dumbledore refusing to expel him because the poor boy didn't know?"

Professor Quirrell's hands whitened on the inkwell. "Do you have a point, Mr. Potter, or are you just stating the obvious?"

"Professor Quirrell," said Harry gravely, "all the Muggle-raised students in Hogwarts need a safety lecture in which they are told the things so ridiculously obvious that no wizardborn would ever think to mention them. Don't cast curses if you don't know what they do, if you discover something dangerous don't tell the world about it, don't brew high-level potions without supervision in a bathroom, the reason why there are underage magic laws, all the basics."

"Why?" said Professor Quirrell. "Let the stupid ones die before they breed."

"If you don't mind losing a few sixth-year Slytherins along with them."

The inkwell caught fire in Professor Quirrell's hands and burned with a terrible slowness, hideous black-orange flames tearing at the metal and seeming to take tiny bites from it, the silver twisting as it melted, as though it were trying and failing to escape. There was a tinny shrieking sound, as though the metal were screaming.

"I suppose you are right," Professor Quirrell said with a resigned smile. "I shall design a lecture to ensure that Muggleborns who are too stupid to live do not take anyone valuable with them as they depart."

The inkwell went on screaming and burning in Professor Quirrell's hands, tiny droplets of metal, still on fire, now dripping to the desk, as though the inkwell were crying.

"You're not running away," observed Professor Quirrell.

Harry opened his mouth -

"If you're about to say you're not scared of me," said Professor Quirrell, "don't."

"You are the scariest person I know," Harry said, "and one of the top reasons for that is your control. I simply can't imagine hearing that you'd hurt someone you had not made a deliberate decision to hurt."

The fire in Professor Quirrell's hands winked out, and he carefully placed the ruined inkwell on his desk. "You say the nicest things, Mr. Potter. Have you been taking lessons in flattery? From, perhaps, Mr. Malfoy?"

Harry kept his expression blank, and realized one second too late that it might as well have been a signed confession. Professor Quirrell didn't care what your expression looked like, he cared which states of mind made it likely.

"I see," said Professor Quirrell. "Mr. Malfoy is a useful friend to have, Mr. Potter, and there is much he can teach you, but I hope you have not made the mistake of trusting him with too many confidences."

"He knows nothing which I fear becoming known," said Harry.

"Well done," said Professor Quirrell, smiling slightly. "So what was your original business here?"