Harry Potter and the Methods of Rationality

The Dementor's speech hurt their ears as it said, "Bellatrix Black is out of her cell."

There was a split second of horrified silence, and then Li tore out of his chair, heading for the communicator to call in reinforcements from the Ministry, even as McCusker grabbed his mirror and started frantically trying to raise the three Aurors who'd gone on patrol.

Chapter 55: The Stanford Prison Experiment, Pt 5

In a scarred and ruined corridor, lit by dim gas lights, a boy slowly crept forward, one hand stretched out, toward the unmoving snake that was the body of his teacher.

Harry was only a meter away from the snake's body when he first felt it, tickling at the edge of his perception.

Ever so weakly, a sense of doom...

Professor Quirrell was alive, then.

The thought engendered no feeling of joy, only a sort of empty despair.

Harry would still be caught soon, and no matter how he tried to explain, it still wouldn't look good. No one would trust him again, they would think he was the next Dark Lord, they wouldn't help him when it came time to fight Lord Voldemort, Hermione would give up on him, probably even Dumbledore would look for another hero...

...maybe they'd just send him home to his parents.

He had failed.

Harry looked at the crumpled body of the police officer he'd stunned, the already-drying blood from the minor cuts and slashes, the burned places on the intricately embroidered red robes.

He'd been stupid. He shouldn't have stunned the police officer, should have just stayed with his original story about being kidnapped by Professor Quirrell...

It might not be too late, whispered a voice inside him. You might still be able to fix your mistake. The Auror saw you, he remembers that you stunned him... but if he were dead, if Professor Quirrell were dead, if Bellatrix were dead, there would be no one to contradict your story.

Slowly, Harry's hand started to rise, pointing his wand at the police officer and -

Harry's hand halted.

He had a distant sense he was behaving uncharacteristically of himself, somehow. Like there was something he'd forgotten, something important, but he was having trouble remembering what it was, exactly.

Oh. That was right. He was someone who believed in the value of human life.

A sense of puzzlement accompanied the thought, he couldn't quite remember why other people's lives had seemed valuable...

All right, said the logical part of him, why has my mind changed between then and now?

Because he was in Azkaban...

And he'd forgotten to recast the Patronus Charm...

Doing anything at all, somehow, seemed like a tremendous effort, like the thought of action itself was a weight too heavy to lift; but it did seem like a good idea to recast the Patronus Charm, for he was still able to be afraid of Dementors. And though he couldn't remember what it was like to be happy, he knew that this wasn't it.

Harry's hand rose to hold his wand level before him, his fingers took the starting positions.

And then Harry paused.

He couldn't... quite remember... what he'd used as his happy thought.

That was odd, it had been something very important, he really ought to be able to remember it... something to do with death? But that wasn't happy...

His body was shivering, Azkaban hadn't seemed so cold before, and it seemed to be getting colder even as he thought. It was too late for him, he'd already sunk too far, he'd never be able to cast the Patronus Charm now -

That may be the Dementation talking rather than an accurate estimate, observed the logical part of himself, habits that had been encoded into sheer reflex, requiring no energy to activate. Think of the Dementors' fear as a cognitive bias, and try to overcome it the way you would overcome any other cognitive bias. Your hopeless feelings may not indicate that the situation is actually hopeless. It may only indicate that you are in the presence of Dementors. All negative emotions and pessimistic estimates must now be considered suspect, fallacious until proven valid.

(If you'd been watching the boy as he thought, you would have seen a distant, abstract, puzzled frown move across his face, below the glasses and the lightning-bolt scar. His hand stayed in the starting position for the Patronus Charm, and did not move.)

The presence of Dementors interferes with the part of you that processes happiness. If you cannot retrieve your happy thought by mnemonic association on the key of happiness, perhaps you can get at the memory some other way instead. When was the last time you talked to someone about the Patronus Charm?

Harry couldn't seem to remember that either.

A crushing wave of despair swept over him, and was dismissed by the logical part of himself as untrustworthy, external, not-Harry, the dull weight still pressed him down but his mind went on thinking, it didn't take much effort to think...