Eliezer Yudkowsky - Harry Potter and the Methods of Rationality

When the light ended it was like a shock, Draco's hand went automatically to his robe to bring out a handkerchief, and it was only then that he realized he was crying.

"There is your experimental result," Harry's voice said quietly. "I really did mean it, that thought."

Draco slowly turned toward Harry, who had lowered his wand now.

"That, that's got to be a trick, right?" Draco said. He couldn't take many more of these shocks. "Your Patronus - can't really be that bright -" And yet it had been Patronus light, once you knew what you were looking at, you couldn't mistake it for anything else.

"That was the true form of the Patronus Charm," Harry said. "Something that lets you put all your strength into the Patronus, without hindrance from within yourself. And before you ask, I did not learn it from Dumbledore. He does not know the secret, and could not cast the true form if he did. I solved the puzzle for myself. And I knew, once I understood, that this spell must not be spoken of. For your sake, I undertook your test; but you must not speak of it, Draco."

Draco didn't know any more, he didn't know where the true strength lay, or the right of things. Double vision, double vision. Draco wanted to call Harry's ideals weakness, Hufflepuff foolishness, the sort of lie that rulers told to placate the populace and that Harry had been silly enough to believe for himself, foolishness taken seriously and raised up to insane heights, projected out onto the stars themselves -

Something beautiful and hidden, mysterious and bright -

"Will I," whispered Draco, "be able to cast a Patronus like that, someday?"

"If you always keep seeking the truth," Harry said, "and if you don't refuse the warm thoughts when you find them, then I'm sure you will. I think a person could get anywhere if they just kept going long enough, even to the stars."

Draco wiped his eyes with his handkerchief again.

"We should go back inside," Draco said in an unsteady voice, "someone could've seen it, all that light -"

Harry nodded, and moved to and through the door; and Draco looked up at the night sky one last time before he followed.

Who was the Boy-Who-Lived, that he was already an Occlumens, and could cast the true form of the Patronus Charm, and do other strange things? What was Harry's Patronus, why must it stay unseen?

Draco didn't ask any of those questions, because Harry might have answered , and Draco just couldn't take any more shocks today. He just couldn't . One more shock and his head was going to just fall right off his shoulders and go bounce, bounce, bounce down the corridors of Hogwarts.

They'd ducked into a small alcove, instead of going all the way back to the classroom, at Draco's request; he was feeling too nervous to put it off any longer.

Draco put up a Quieting barrier, and then looked at Harry in silent question.

"I've been thinking about it," Harry said. "I'll do it, but there are five conditions -"

" Five? "

"Yes, five. Look, Draco, a pledge like this is just begging to go terribly wrong somehow, you know it would go wrong if this were a play -"

"Well, it's not!" Draco said. "Dumbledore killed Mother. He's evil. It's one of those things you talk about that doesn't have to be complicated."

"Draco," Harry said, his voice careful, "all I know is that you say that Lucius says that Dumbledore says he killed Narcissa. To believe that unquestioningly, I have to trust you and Lucius and Dumbledore. So like I said, there are conditions. The first one is that at any point you can release me from the pledge, if it no longer seems like a good idea. It has to be a deliberate and intended decision on your part, of course, not a trick of wording or something."

"Okay," said Draco. That sounded safe enough.

"Condition two is that I'm pledging to take as an enemy whoever actually did kill Narcissa, as determined to the honest best of my ability as a rationalist. Whether that's Dumbledore, or someone else. And you have my word that I'll exercise my best ability as a rationalist to keep that judgment honest, as a question of simple fact. Agreed?"

"I don't like it," said Draco. He didn't, the whole point was to make sure Harry never went with Dumbledore. Still, if Harry was honest, he'd catch on to Dumbledore soon enough; and if dishonest, he'd already broken his word... "But I'll agree."

"Condition three is that Narcissa has to have been burned alive . If that part of the story turns out to be something exaggerated just to make it sound a little worse, then I get to decide for myself whether or not to still go through with the pledge. Good people sometimes have to kill. But they don't ever torture people to death. It's because Narcissa was burned alive that I know whoever did that was evil."

Draco kept his temper, barely.

"Condition four is that if Narcissa got her own hands dirty, and, say, Crucioed someone's child into insanity, and that person burned Narcissa for revenge, the deal might be off again. Because then it was still wrong for them to burn her, they still should've just killed her without pain; but it wasn't evil the same way as if she was just Lucius's love who never did anything herself, like you said. Condition five is that if whoever killed Narcissa was tricked somehow into doing it, then my enemy is whoever tricked them, not the person who was tricked."

"All this really sounds like you're planning to weasel out of it -"

"Draco, I won't take a good person as an enemy, not for you or anyone. I have to really believe they're in the wrong. But I've thought about it, and it seems to me that if Narcissa didn't do any evil with her own hands, just fell in love with Lucius and chose to stay his wife, then whoever burned her alive in her own bedroom isn't likely to be a good guy. And I'll pledge to take as my enemy whoever made that happen, whether it's Dumbledore or anyone else, unless you deliberately release me from that pledge. Hopefully that won't go wrong the way it would if this were a play."

"I'm not happy," said Draco. "But okay. You pledge to take my mother's murderer as your enemy, and I'll -"

Harry waited, with a patient look on his face, while Draco tried to make his voice work again.

"I'll help you fix the problem with Slytherin House hating Muggleborns," Draco finished in a whisper. "And I'll say it was sad that Lily Potter died."

"So be it," said Harry.

And it was done.

The break, Draco knew, had just widened a little more. No, not a little, a lot. There was a sensation of drifting away, of being lost, further and further from shore, further and further from home...

"Excuse me," Draco said. He turned away from Harry, and then tried to calm himself, he had to do this test, and he didn't want to fail it from being nervous or ashamed.

Draco raised his wand into the starting position for the Patronus Charm.

Remembered falling from his broomstick, the pain, the fear, imagined it coming from a tall figure in a cloak, looking like a dead thing left in water.

And then Draco closed his eyes, the better to remember Father holding his small, cold hands in his own warm strength.

Don't be frightened, my son, I'm here...

The wand swung up in a broad brandish, to drive the fear away, and Draco was surprised at the strength of it; and he remembered in that moment that Father wasn't lost, would never be lost, would always be there and strong in his own person, no matter what happened to Draco, and his voice cried, "Expecto Patronum!"

Draco opened his eyes.

A shining snake looked back at him, no less bright than before.