Harry Potter and the Methods of Rationality

"Go ahead," said Harry, his heart starting to beat faster.

"What is your opinion of the government of magical Britain?"

That wasn't quite what Harry had been expecting, but it was close enough, so Harry said, "Based on my limited knowledge, I would say that both the Ministry and the Wizengamot appear to be stupid, corrupt, and evil."

"Correct," Professor Quirrell said. "Do you understand why I ask?"

Harry took a deep breath, and looked Professor Quirrell straight in the eyes, unflinching. Harry had finally worked out that the way to make amazing deductions from scanty evidence was to know the answer in advance, and he had guessed this answer fully a week ago. It needed only a slight adjustment...

"You are about to invite me to join a secret organization full of interesting people like yourself," said Harry, "one of whose goals is to reform or overthrow the government of magical Britain, and yes, I'm in."

There was a slight pause.

"I'm afraid that is not quite where I intended to direct this conversation," said Professor Quirrell. The corners of his lips were twitching slightly. "I merely planned to ask for your help in doing something extremely treasonous and illegal."

Darn, thought Harry. Still, Professor Quirrell hadn't denied it... "Go on."

"Before I do," said Professor Quirrell. There was no levity in his voice, now. "Are you open to such requests, Mr. Potter? I say again that if you are likely to say no regardless, you must say no now. If your curiosity impels you otherwise, squash it."

"Treasonous and illegal doesn't bother me," said Harry. "Risks bother me and the stakes would need to be commensurate, but I can't imagine you taking risks frivolously."

Professor Quirrell nodded. "I would not. It is a terrible abuse of my friendship with you, and of such trust as is placed in my teaching position at Hogwarts -"

"You can skip this part," Harry said.

The lips twitched again, and then went flat. "Then I shall skip it. Mr. Potter, you sometimes make a game of lying with truths, playing with words to conceal your meanings in plain sight. I, too, have been known to find that amusing. But if I so much as tell you what I hope we shall do this day, Mr. Potter, you will lie about it. You will lie straight out, without hesitation, without wordplay or hints, to anyone who asks about it, be they foe or closest friend. You will lie to Malfoy, to Granger, and to McGonagall. You will speak, always and without hesitation, in exactly the fashion you would speak if you knew nothing, with no concern for your honor. That also is how it must be."

There was silence, then, for a time.

That was a price measured in a fraction of Harry's soul.

"Without telling me yet..." said Harry. "Can you say if the need is desperate?"

"There is someone in the most terrible want of your help," Professor Quirrell said simply, "and there is no one who can help them but you."

There was another silence, but not a long one.

"All right," Harry said quietly. "Tell me of the mission."

The dark robes of the Defense Professor seemed to blur against the shadow on the wall, cast by his silhouette blocking the white light of Harry's wand. "The ordinary Patronus Charm, Mr. Potter, wards off a Dementor's fear. But the Dementors still see you through it, they know that you are there. Only not your Patronus Charm. It blinds them, or more than blinds them. What I saw beneath the cloak wasn't even looking in our direction as you killed it; as though it had forgotten our existence, even as it died."

Harry nodded. That wasn't surprising, not when you confronted a Dementor on the level of its true existence, beyond anthropomorphism. Death might be the last enemy, but it wasn't a sentient enemy. When humanity had wiped out smallpox, smallpox hadn't fought back.

"Mr. Potter, the central branch of Gringotts is guarded by every spell high and low that the goblins know. Even so those vaults have been successfully robbed; for what wizardry can do, wizardry can undo. And yet no one has ever escaped from Azkaban. No one. For every Charm there is a counter-Charm, for every ward there is a bypass. How can it be that no one has ever been rescued from Azkaban?"

"Because Azkaban has something invincible," Harry said. "Something so terrible that no one can defeat it."

That was the keystone of their perfect security, it had to be, nothing human. It was Death that guarded Azkaban.

"The Dementors don't like their meals being taken away from them," Professor Quirrell said. Coldness had entered that voice, now. "They know if anyone tries. There are more than a hundred Dementors there, and they speak to the guards as well. It's that simple, Mr. Potter. If you're a powerful wizard then Azkaban isn't hard to enter, and it isn't hard to leave. So long as you don't try to take anything out of it that belongs to the Dementors."

"But the Dementors are not invincible," said Harry. He could have cast the Patronus Charm with that thought, in that very moment. "Never believe that they are."

Professor Quirrell's voice was very quiet. "Do you remember what it was like when you went before the Dementor, the first time, when you failed?"

"I remember."

And then with a sudden sickening lurch in his stomach, Harry knew where this was going; he should have seen it before.

"There is an innocent person in Azkaban," Professor Quirrell said.