Harry Potter and the Methods of Rationality

Slowly, Harry lowered his hand. "I wasn't going to hurt him, Hermione," Harry said, his voice a little lower. "I was just going to blow up the door."

Though now that Harry remembered it, you weren't supposed to Transfigure things that were to be burned, which meant that going back in time afterward and getting Fred or George to Transfigure some carefully measured amount of explosives might not actually have been such a good idea...

"Silencio," said Severus's voice.

Harry tried to say "What?" and found that no sound was coming out.

"This has become ridiculous. I think you've been allowed to get yourself in enough trouble for one day, Potter. You are the most disruptive and unruly student I have ever seen, and I don't recall how many points Ravenclaw has right now, but I'm sure I can manage to wipe them all out. Ten points from Ravenclaw. Ten points from Ravenclaw. Ten points from Ravenclaw! Fifty points from Ravenclaw! Now sit down and watch the rest of the class take their lesson!"

Harry put his hand into his pouch and tried to say 'marker' but of course no words came out. For one brief moment that stopped him; and then it occurred to Harry to spell out M-A-R-K-E-R using finger motions, which worked. P-A-D and he had a pad of paper. Harry strode over to an empty desk, not the one he'd originally sat down in, and scrawled a brief message. He tore off that sheet of paper, put away the marker and pad in a pocket of his robes for quicker access, and held up his message, not to Snape, but to the rest of the class.

I'M LEAVING

DOES ANYONE ELSE

NEED TO GET OUT?

"You're insane, Potter," Severus said with cold contempt.

Aside from that, no one spoke.

Harry swept an ironic bow to the teacher's desk, walked over to the wall, and with one smooth motion yanked open a closet door, stepped in, and slammed the door shut behind him.

There was the muffled sound of someone snapping his fingers, and then nothing.

In the classroom, students looked at each other in puzzlement and fear.

The Potions Master's face was now completely enraged. He crossed the room in terrible strides and yanked open the closet door.

The closet was empty.

One hour earlier, Harry listened from inside the closed closet. There was no sound from outside, and no point in taking risks either.

C-L-O-A-K, his fingers spelled out.

Once he was invisible, he very carefully and slowly cracked open the closet door and peeked out. No one seemed to be in the classroom.

The door wasn't locked.

It was when Harry was outside the dangerous place and inside the hallway, safely invisible, that some of the anger drained away and he realized what he'd just done.

What he'd just done.

Harry's invisible face was frozen in absolute horror.

He'd antagonized a teacher three orders of magnitude beyond anything he'd ever managed before. He'd threatened to walk out of Hogwarts and might have to follow through on it. He'd lost all the points Ravenclaw had and then he'd used the Time-Turner...

His imagination showed him his parents yelling at him after he was expelled, Professor McGonagall disappointed in him, and it was just too painful and he couldn't bear it and he couldn't think of any way to save himself -

The thought that Harry allowed himself to think was that if getting angry had gotten him into all this trouble, then maybe when he was angry he'd think of a way out, things seemed clearer somehow when he was angry.

And the thought that Harry didn't let himself think was that he just couldn't face this future if he wasn't angry.

So he cast his thoughts back and remembered the burning humiliation -

Tut, tut. Fame clearly isn't everything.

Ten points from Ravenclaw for backchat.

The calming cold washed back through his veins like a wave reflected and returning from some breaker, and Harry let out his breath.

Okay. Back to being sane now.

He was actually feeling a bit disappointed in his non-angry self for collapsing like that and wanting only to get out of trouble. Professor Severus Snape was everyone's problem. Normal-Harry had forgotten that and wished for a way to protect himself. And let all the other victims go hang? The question wasn't how to protect himself, the question was how to destroy this Potions professor.

So this is my dark side, is it?Bit of a prejudiced term that, my light side seems more selfish and cowardly, not to mention confused and panicky.

And now that he was thinking clearly, it was equally clear what to do next. He'd already given himself an extra hour to prepare, and could get up to five hours more if required...

Minerva McGonagall waited in the Headmaster's office.