Eliezer Yudkowsky - Harry Potter and the Methods of Rationality

“Interesting,” said Professor Quirrell, as he floated down from above, not touching any of the plant’s leaves or tendrils. “I notice that you seem to have no trouble losing to a plant.”

Harry looked more closely at the Defense Professor, seeing him now without the lens of panic. Professor Quirrell was upright and moving, flying without apparent difficulty; the sense of doom about him was strong. But his eyes were still sunken in the skull, his arms thin and wasted. The sickness had not been bluff, and the obvious hypothesis was that the Defense Professor had recently eaten another unicorn to temporarily regain some strength.

And the Defense Professor was also speaking like the mask of Professor Quirrell, not like Lord Voldemort, which might not be a bad thing from Harry’s perspective. Harry didn’t know why—unless it was that the Defense Professor still needed him for something—but it certainly seemed to be in Harry’s own interests to play along.

“You specifically let me walk into this trap, Professor,” Harry answered, just the way he’d have spoken to Professor Quirrell. Roles, masks, remind him of how it was between us… “On my own, I’d have used my broomstick.”

“Perhaps. How would an ordinary first-year solve this challenge? If they had their wand, that is.” The plant was now reaching tendrils out toward Professor Quirrell, but Professor Quirrell was hovering just out of their reach.

Harry had now remembered Professor Sprout talking about a Devil’s Snare plant, which the Herbology textbook had said liked cool, dark places like caves—though how that could be true of a leafy plant was anyone’s guess. “At a guess, I’d say this is a Devil’s Snare plant and it might retreat from light or heat. So maybe a first-year could use Lumos?

Today I’d use Inflammare , but I didn’t learn that spell until May.”

A twirl of the Defense Professor’s wand, and a pattern of sprays of liquid shot out from it, striking the plant near the bases of its tendrils, hitting with a quiet splat and then a quiet hissing. All the tendrils touching Harry frantically shot back and began to beat at the growing wounds appearing on the plant’s skin, as if trying to remove the pain-stimulus; something about the plant gave the impression that it was screaming soundlessly.

Professor Quirrell finished drifting downward. “Now it is afraid of light, heat, acid, and me.”

Harry stepped off the final leaves onto the floor, after a careful glance at his robes and then the floor to make sure that none of the acid had splashed anywhere. Harry had begun to suspect that Professor Quirrell was trying to make some sort of point, but Harry did not know what that point might be. “I thought we were on a mission, Professor. I can’t stop you, but is it smart to spend this much time on messing with me?”

“Oh, we have time,” said Professor Quirrell, sounding amused. “There would be a great uproar if we were discovered here, guarded by an Inferius. You did not act like you had heard of such an uproar at your Quidditch match, before you arrived in this time and spoke to Snape as you did.”

A slight chill came over Harry, as he comprehended this. Anything he did to beat Professor Quirrell would have to not disrupt the school, or at least the Quidditch game, because it hadn’t disrupted the Quidditch game. Even if enough forces could be called in to subdue Lord Voldemort, it might not be easy to do it without Professor McGonagall or Professor Flitwick or anyone else at the Quidditch game noticing… Fighting a smart enemy was hard.

And even so… even so it seemed to Harry that if he stood in Professor Quirrell’s shoes, he would notbe having leisurely conversations and playing mind games. Professor Quirrell was gaining something by taking his time here. But what? Was there some other process that had to run to completion?

“By the by, have you betrayed me yet?” said Professor Quirrell.

“ Have not betrayed you yet, ” Harry hissed.

The Defense Professor gestured pointedly with the gun he was now holding in his left hand, and Harry walked ahead to the great wooden door at the end of the room, and opened it.

The next chamber was smaller in diameter, with a higher ceiling. The light shining out of the arched alcoves was white, instead of blue.

Around them whizzed hundreds of winged keys, beating frantically through the air. After watching for a few seconds, it became clear that only a single key was the golden color of a Snitch—though it was moving slower than a Snitch in a real Quidditch game.

On the other end of the room was a door containing a large, prominent keyhole.

Against the left wall leaned a broomstick, the school’s workhorse Cleansweep Seven.

“Professor,” Harry said, staring up at the clouds and flocks of whizzing keys, “you said you would answer my questions. What exactly is all this about? If you think you’ve secured a door so that it won’t open without a key, you keep the key in a safe place and only give a copy to authorized entrants. You don’t give the key wings and then leave a broomstick propped against the wall. So what the heck are we doing in here and what is going on? It’s an obvious guess that the magic mirror is the only real factor guarding the Stone, but why the rest of this—and why encourage first-years to come here?”

“I am truly not sure,” said the Defense Professor. He had entered the room and taken up station well to Harry’s right, maintaining the distance between them. “But I shall answer, as I said I would. Dumbledore’s way is to do a dozen things which seem mad, and then only eight of them, or perhaps nine, conceal an inner meaning. My guess is that Dumbledore intends to make it seem like I am invited to send a student as my proxy. Precisely so that Lord Voldemort, as Dumbledore conceives of him, is less tempted to think himself clever by doing so. Imagine Dumbledore first considering the issue of how to ward the Stone. Imagine Dumbledore considering whether to set true dangers to guard the Mirror. Imagine him imagining some young student blundering through those dangers at my behest. I think that is what Dumbledore is trying to avoid, by making it seem as though that strategy is invited, and so not cunning. Unless, of course, I have misunderstood what Dumbledore thinks Lord Voldemort will think.” Professor Quirrell grinned, and it looked just as natural, on him, as any grin he’d shown Harry before. “Plotting does not come naturally to Dumbledore, but he tries because he must. To that task Dumbledore brings intelligence, dedication, the ability to learn from his mistakes, and an utter lack of native talent. He is marvelously hard to predict for that reason alone.”

Harry turned away, looking at the door on the opposite side of the room. It wasn’t a game to him, Professor. “My guess is that the intended solution for first-years is to ignore the broomstick and use Wingardium Leviosa to grab the key, since this isn’t a Quidditch game and there are no rules forbidding that. So what absurdly overpowered spell are you going to unleash on this one, then?”

There was a brief silence but for the whizzing of keys.

Harry took several steps away from Professor Quirrell. “I probably shouldn’t have said that, should I.”

“Oh, no,” Professor Quirrell said. “I think that is a quite reasonable thing to say to the most powerful Dark Wizard in the world when he is standing not a dozen paces from you.”

Professor Quirrell put his wand back into the sleeve of his other hand, the hand that sometimes held the gun.

Then the Defense Professor reached into his mouth and took out what appeared to be a tooth. He tossed the false tooth high in the air, and when it came down, it had transformed into a wand that sparked a strange sense of recognition in Harry’s mind, as though some part of him recognized that wand as being… part of him…