Harry Potter and the Methods

Hermione's jaw dropped. She had the distinct feeling of something terribly unfair having been done to her, that the boy was a dirty rotten cheating liar, but when she cast her mind back she couldn't think of any wrong responses that he'd given.

"What you've just discovered is called 'positive bias'," said the boy. "You had a rule in your mind, and you kept on thinking of triplets that should make the rule say 'Yes'. But you didn't try to test any triplets that should make the rule say 'No'. In fact you didn't get a single 'No', so 'any three numbers' could have just as easily been the rule. It's sort of like how people imagine experiments that could confirm their hypotheses instead of trying to imagine experiments that could falsify them - that's not quite exactly the same mistake but it's close. You have to learn to look on the negative side of things, stare into the darkness. When this experiment is performed, only 20% of grownups get the answer right. And many of the others invent fantastically complicated hypotheses and put great confidence in their wrong answers since they've done so many experiments and everything came out like they expected."

"Now," said the boy, "do you want to take another shot at the original problem?"

His eyes were quite intent now, as though this were the real test.

Hermione shut her eyes and tried to concentrate. She was sweating underneath her robes. She had an odd feeling that this was the hardest she'd ever been asked to think on a test or maybe even the first time she'd ever been asked to think on a test.

What other experiment could she do? She had a Chocolate Frog, could she try to rub some of that on the robes and see if it vanished? But that still didn't seem like the kind of twisty negative thinking the boy was asking for. Like she was still asking for a 'Yes' if the Chocolate Frog stain disappeared, rather than asking for a 'No'.

So... on her hypothesis... when should the pop... notvanish?

"I have an experiment to do," Hermione said. "I want to pour some pop on the floor, and see if it doesn't vanish. Do you have some paper towels in your pouch, so I can mop up the spill if this doesn't work?"

"I have napkins," said the boy. His face still looked neutral.

Hermione took the can, and poured a small bit of pop onto the floor.

A few seconds later, it vanished.

Then the realisation hit her and she felt like kicking herself. "Of course! You gave me that can! It's not the robe that's enchanted, it was the pop all along!"

The boy stood up and bowed to her solemnly. He was grinning widely now. "Then... may I help you with your research, Hermione Granger?"

"I, ah..." Hermione was still feeling the rush of euphoria, but she wasn't quite sure about how to answer that.

They were interrupted by a weak, tentative, faint, rather reluctant knocking at the door.

The boy turned and looked out the window, and said, "I'm not wearing my scarf, so can you get that?"

It was at this point that Hermione realised why the boy - no, the Boy-Who-Lived, Harry Potter - had been wearing the scarf over his head in the first place, and felt a little silly for not realising it earlier. It was actually sort of odd, since she would have thought Harry Potter would proudly display himself to the world; and the thought occurred to her that he might actually be shyer than he seemed.

When Hermione pulled the door open, she was greeted by a trembling young boy who looked exactly like he knocked.

"Excuse me," said the boy in a tiny voice, "I'm Neville Longbottom. I'm looking for my pet toad, I, I can't seem to find it anywhere on this carriage... have you seen my toad?"

"No," Hermione said, and then her helpfulness kicked in full throttle. "Have you checked all the other compartments?"

"Yes," whispered the boy.

"Then we'll just have to check all the other carriages," Hermione said briskly. "I'll help you. My name is Hermione Granger, by the way."

The boy looked like he might faint with gratitude.

"Hold on," came the voice of the other boy - Harry Potter. "I'm not sure that's the best way to do it."

At this Neville looked like he might cry, and Hermione swung around, angered. If Harry Potter was the sort of person who'd abandon a little boy just because he didn't want to be interrupted... "What? Why not?"

"Well," said Harry Potter, "It's going to take a while to check the whole train by hand, and we might miss the toad anyway, and if we didn't find it by the time we're at Hogwarts, he'd be in trouble. So what would make a lot more sense is if he went directly to the front carriage, where the prefects are, and asked a prefect for help. That was the first thing I did when I was looking for you, Hermione, although they didn't actually know. But they might have spells or magic items that would make it a lot easier to find a toad. We're only first-years."

That... did make a lot of sense.

"Do you think you can make it to the prefects' carriage on your own?" asked Harry Potter. "I've sort of got reasons for not wanting to show my face too much."

Suddenly Neville gasped and took a step back. "I remember that voice! You're one of the Lords of Chaos! You're the one who gave me chocolate!"

What? What what what?

Harry Potter turned his head from the window and rose dramatically. "I never!" he said, voice full of indignation. "Do I look like the sort of villain who would give sweets to a child?"

Neville's eyes widened. "You're Harry Potter? The Harry Potter? You?"

"No, just a Harry Potter, there are three of me on this train -"

Neville gave a small shriek and ran away. There was a brief pattering of frantic footsteps and then the sound of a carriage door opening and closing.

Hermione sat down hard on her bench. Harry Potter closed the door and then sat down next to her.

"Can you please explain to me what's going on?" Hermione said in a weak voice. She wondered if hanging around Harry Potter meant always being this confused.

"Oh, well, what happened was that Fred and George and I saw this poor small boy at the train station - the woman next to him had gone away for a bit, and he was looking really frightened, like he was sure he was about to be attacked by Death Eaters or something. Now, there's a saying that the fear is often worse than the thing itself, so it occurred to me that this was a lad who could actually benefit from seeing his worst nightmare come true and that it wasn't so bad as he feared -"

Hermione sat there with her mouth wide open.

"- and Fred and George came up with this spell to make the scarves over our faces darken and blur, like we were undead kings and those were our grave shrouds -"

She didn't like at all where this was going.