Harry Potter and the Methods of Rationality

"Chocolate," Albus Dumbledore said, "you need chocolate, and your friends - but I dare not take you back -"

Then a shining raven came, and spoke in Professor Flitwick's voice; whereupon Albus Dumbledore gasped in sudden comprehension, and cursed aloud at his own stupidity.

The empty thing laughed at that, for it had retained the capacity to be amused.

And a moment later they had all vanished in another flash of fire.

It was only a moment, it seemed, between when Flitwick's raven had flown to elsewhere, and when Albus Dumbledore reappeared in another crack of red and golden fire with Harry in his arms; but somehow in that time Hermione had already managed to fill her hands with chocolate.

Before Hermione even got there, chocolate had zoomed off the table and straight into Harry's mouth, which a tiny part of her mind said was unfair, he'd gotten a chance to do it for her -

Harry spat the chocolate back out again.

"Go away," said a voice so empty it wasn't even cold.

...

Everything seemed to freeze, everyone who had been moving toward Harry halted, all movements broken by the shock of those two dead words.

Then: "No," said Albus Dumbledore, "I will not," and time resumed again, even as another piece of chocolate zoomed off the table and into Harry's mouth.

Hermione was close enough now that she could see Harry's expression become more hateful, as his mouth chewed with a mechanical, unnatural rhythm.

The Headmaster's voice was grim as iron. "Filius, call Minerva, tell her she must come at speed."

Professor Flitwick whispered to his silver raven, and it flew into the air and vanished.

Another piece of chocolate floated into Harry's mouth, and the mechanical chewing continued.

There were more students gathering around where the Headmaster watched over Harry with grim eyes: Neville, Seamus, Dean, Lavender, Ernie, Terry, Anthony, none of them daring to approach any closer than Hermione had.

"What can we do?" said Dean in a trembling voice.

"Back off and give him more space -" said the dry voice of Professor Quirrell.

"No!" interrupted the Headmaster. "Let him be surrounded by his friends."

Harry swallowed his chocolate, and said in that empty voice, "They're stupid. They should diemmmppphhh" as another piece of chocolate entered his mouth.

Hermione saw the looks of shock that crossed their faces.

"He doesn't mean it, does he?" Seamus said it like he was begging.

"You don't understand," Hermione said, her voice breaking, "that's not Harry -" and she shut up before she said anything more, but she had to say that much.

She saw from the look on his face that Neville understood, and she also saw that the others didn't. If Harry had really never thought anything like that, then being exposed to a Dementor for less than a minute wouldn't have made him say it. That's what they were probably thinking.

Less than a minute of Dementor exposure couldn't create a whole new evil person inside you out of nothing.

But if that person was already there -

Does the Headmaster know?

Hermione looked up at the Headmaster, and found that Albus Dumbledore was gazing at her, and that his blue eyes had grown suddenly piercing -

Words came into her mind.

Do not speak of it, said the will of Dumbledore to her.

You know, thought Hermione. About his dark side.

I know. But this is beyond even that. Fawkes's song cannot reach him, where he is lost.

What can we -

I have a plan, sent the Headmaster. Patience.

Something about the tenor of that thought made Hermione nervous. What sort of plan?

It is better that you not know, sent the Headmaster.

Now Hermione was getting really nervous. She didn't know how much the Headmaster knew about Harry's dark side -

A fair point, sent the Headmaster. I am about to tell you; steel yourself so as not to react. Are you ready? Good. I am going to pretend to cast the Killing Curse on Professor McGonagall - DO NOT REACT, Hermione!

That took work. The Headmaster really was crazy! That wouldn't bring Harry out of