Harry Potter and the Methods of Rationality

'It's all right,' said Professor Quirrell's voice, which suddenly sounded a lot weaker than usual. 'Sit down, Mr. Potter, it's just a dizzy spell. Sit down.'

Harry's fingers gripped the edge of his chair, uncertain as to what he should do, what he could do. Harry couldn't even get too close to Professor Quirrell, not unless he wanted to defy that sense of Doom -

Professor Quirrell straightened, then, his breathing seeming a bit heavy, and opened the door.

The waitress came in, bearing a platter of food; and as she distributed the plates, Professor Quirrell walked slowly back to the table.

But by the time the waitress had bowed her way out, Professor Quirrell was sitting upright and smiling again.

Still, the brief episode of whatever-it-was had decided Harry. He couldn't say no, not after Professor Quirrell had gone to that much trouble.

'Yes,' Harry said.

Professor Quirrell held up a cautioning finger, then took out his wand again, locked the door again, and repeated three of the same Charms from earlier.

Then Professor Quirrell took the book back out of his robes and tossed it to Harry, who almost dropped it into his soup.

Harry shot Professor Quirrell a look of helpless indignation. You weren't supposed to do that with books, enchanted or not.

Harry opened the book with ingrained, instinctive care. The pages seemed too thick, with a texture unlike either Muggle paper or wizarding parchment. And the contents were...

...blank?

'Am I supposed to be seeing -'

'Look nearer the beginning,' said Professor Quirrell, and Harry (again with that helpless, ingrained care) turned a block of pages back.

The lettering was obviously handwritten, and very hard to read, but Harry thought the words might be Latin.

'What is this?' said Harry.

'That,' said Professor Quirrell, 'is a record of the magical researches of a Muggleborn who never came to Hogwarts. He refused his letter, and conducted his own small investigations, which never did get very far without a wand. From the description on the placard, I expect that his name bears rather more significance to you than to me. That, Harry Potter, is the diary of Roger Bacon.'

Harry almost fainted.

Nestled up against the wall, where Professor Quirrell had stumbled, glistened the crushed remains of a beautiful blue beetle.

Chapter 27: Empathy

J. K. Rowling is 87% confident you will burst into flames.

Roger Bacon lived in the 13th century and is credited as one of the earliest advocates of the scientific method. Giving a scientist his experimental diary is sort of like giving a writer the pen, not of Shakespeare, but of someone who helped invent writing.

It wasn't every day you got to see Harry Potter beg.

'Pleeaaase,' whined Harry Potter.

Fred and George shook their heads again, smiling.

There was an agonized look on Harry Potter's face. 'But I told you how I did the one with Kevin Entwhistle's cat, and Hermione and the vanishing soda, and I can't tell you about the Sorting Hat or the Remembrall or Professor Snape...'

Fred and George shrugged and turned to leave.

'If you ever do figure it out,' said the Weasley twins, 'be sure to let us know.'

'You're evil! You're both evil!'

Fred and George firmly closed the door to the empty classroom behind them, and made sure to keep the grin on their faces for a while, just in case Harry Potter could see through doors.

Then they turned a corner and their faces sagged.

'I don't suppose Harry's guesses -'

'- gave you any ideas?' they said to each other at the same time, and then their shoulders slumped further.

Their last relevant memory was of Flume refusing to help them, though they couldn't remember what they'd asked him to do...

...but they must have looked elsewhere and found someone to help them do something illegal, or they wouldn't have agreed to be Obliviated afterward.

How had they possibly been able to get all that done on just forty Galleons?

At first they'd worried that they'd forged evidence so good that Harry actually would end up married to Ginny... but they'd thought of that too, it seemed. The Wizengamot proceedings had been tampered with again to put them back the way they'd been originally, the fake betrothal contract had vanished from its dragon-guarded vault in Gringotts, and so on. It was pretty scary, actually. Most