Ron Weasley sucks

Finally. JK Rowling's admitted what readers of Yudkowsky's continuum have long known: Ron Weasley sucks. Well, she didn't quite put it that way - she said instead that Hermoine should never have wound up with Weasley. Which is true, because Weasley sucks.

In Harry Potter and the Methods Of Rationality, Potter was trained in the methods of science and rationality before discovering magical Britain. And so he decided to approach magic scientifically to see how it worked. Great fun.

Here's how Yudkowsky's continuum dealt with Weasley. Harry meets him in Chapter 7. We don't hear from him much after that. Which is as it should be.

"Cor," said the red-haired boy, "are you really Harry Potter?"

Not this again. "I have no logical way of knowing that for certain. My parents raised me tobelieve that my name was Harry James Potter-Evans-Verres, and many people here have told me that I look like my parents, I mean my other parents, but," Harry frowned, realising, "for all I know, there could easily be spells to polymorph a child into a specified appearance -"

"Er, what, mate?"

Not headed for Ravenclaw, I take it. "Yes, I'm Harry Potter."

...

[After Ron explains Quidditch]: "So let me get this straight," Harry said as it seemed that Ron's explanation (with associated hand gestures) was winding down. "Catching the Snitch is worth one hundred and fifty points? "

"Yeah -"

"How many ten-point goals does one side usually score not counting the Snitch?"

"Um, maybe fifteen or twenty in professional games -"

"That's just wrong. That violates every possible rule of game design. Look, the rest of this game sounds like it might make sense, sort of, for a sport I mean, but you're basically saying that catching the Snitch overwhelms almost any ordinary point spread. The two Seekers are up there flying around looking for the Snitch and usually not interacting with anyone else, spotting the Snitch first is going to be mostly luck -"

"It's not luck!" protested Ron. "You've got to keep your eyes moving in the right pattern -"

"That's not interactive, there's no back-and-forth with the other player and how much fun is it to watch someone incredibly good at moving their eyes? And then whichever Seeker gets lucky swoops in and grabs the Snitch and makes everyone else's work moot. It's like someone took a real game and grafted on this pointless extra position so that you could be the Most Important Player without needing to really get involved or learn the rest of it. Who was the first Seeker, the King's idiot son who wanted to play Quidditch but couldn't understand the rules?" Actually, now that Harry thought about it, that seemed like a surprisingly good hypothesis. Put him on a broomstick and tell him to catch the shiny thing...

Ron's face pulled into a scowl. "If you don't like Quidditch, you don't have to make fun of it!"

"If you can't criticise, you can't optimise. I'm suggesting how to improve the game. And it's very simple. Get rid of the Snitch."

"They won't change the game just 'cause you say so!"

"I am the Boy-Who-Lived, you know. People will listen to me. And maybe if I can persuade them to change the game at Hogwarts, the innovation will spread."

A look of absolute horror was spreading over Ron's face. "But, but if you get rid of the Snitch, how will anyone know when the game ends?"

"Buy... a... clock. It would be a lot fairer than having the game sometimes end after ten minutes and sometimes not end for hours, and the schedule would be a lot more predictable for the spectators, too." Harry sighed. "Oh, stop giving me that look of absolute horror, I probably won't actually take the time to destroy this pathetic excuse for a national sport and remake it stronger and smarter in my own image. I've got way, way, way more important stuff to worry about." Harry looked thoughtful. "Then again, it wouldn't take much time to write up the Ninety-Five Theses of the Snitchless Reformation and nail it to a church door -"

And the best part: after Ron tells Harry to tell Draco to go away:

Harry counted to ten inside his head, which for him was a very quick 12345678910 - an odd habit left over from the age of five when his mother had first instructed him to do it, and Harry had reasoned that his way was faster and ought to be just as effective. "I'm not telling him to go away," Harry said calmly. "He's welcome to talk to me if he wants."

"Well, I don't intend to hang around with anyone who hangs around with Draco Malfoy," Ron announced coldly.

Harry shrugged. "That's up to you. I don't intend to let anyone say who I can and can't hang around with." Silently chanting, please go away, please go away...

Ron's face went blank with surprise, like he'd actually expected that line to work. Then Ron spun about, yanked his luggage's lead and stormed off down the platform.

"If you didn't like him," Draco said curiously, "why didn't you just walk away?"

"Um... his mother helped me figure out how to get to this platform from the King's Cross Station, so it was kind of hard to tell him to get lost. And it's not that I hate this Ron guy," Harry said, "I just, just..." Harry searched for words.

"Don't see any reason for him to exist?" offered Draco.

"Pretty much."

The whole world anxiously awaits the arrival of Chapter 102. I will provide no further spoilers. But if you thought that Ron Weasley sucked, you really need to read HPMOR. Start with Chapter 1.

Quirrell Points

I continue to enjoy Harry Potter and the Methods of Rationality. Eliezer Yudkowsky there proposes a rather interesting pedagogic technique, via the excellent Professor Quirrell:

"And on the rare occasions I offer you a written test, it will mark itself as you go along, and if you get too many related questions wrong, your test will show the names of students who got those questions right, and those students will be able to earn Quirrell points by helping you."

...wow. Why didn't the other professors use a system like that?

If this could be set up, boy would it take a load off of the lecturer.

Alas, in our muggle world, we're constrained by normal physics and haven't access to magic.

First, I can't see how you could set up a self-scoring test that weren't multiple choice, true/false, or restricted to questions where you can have a numeric or algebraic solution. So that makes it a lot less appealing right from the start. There are some courses in economics for which this could work, just not the courses I'm teaching.

Second, the logistics wouldn't be pretty. Here's the best way I can imagine it working; maybe you can help me out if you're more imaginative.

In Phase One of the test, everyone would sit the test at a computer terminal. Each student is assigned a score for Phase One; the system's back-end also keeps track of competences across subcomponents.

After Phase One, students who did well on subcomponents are given the option to have their names released for tutorial assistance. Students who did poorly are told which students who did well on those subcomponents would be suitable tutors, along perhaps with some reputation score indicating how well they've performed in the past in improving others' grades.

The students who did poorly then are given the chance to sit Phase Two, in which they could re-do the parts they did badly for partial credit. The student assistants are given a part of the re-tested students' score improvement as bonus points.

There's a Muggle-world mechanism design hindrance: You need some way of ensuring that the system can tell which tutors helped which students. Tutors will have an incentive to disavow students who are likely to do poorly, to help keep their averages up. Some poorer students may try to claim a tutor relationship where one didn't exist to drag down the average of too-smug higher performing students like Ms. Granger. If tutors can't disavow students, they're blamed for the ones who didn't show up for the tutorial sessions. There's probably a way around the problem, but it doesn't seem easy. Even if you could sort it out, you'd need a way of programming it into the various online course management systems.

If I ever figure out a way of having online-only self-grading tests, I'd start thinking harder about these mechanism design issues.

Rationalist reading

It's hard to fit magic into the rational universe. What happens to the laws of physics around conservation of mass if a wizard can turn herself into a cat?

I'd missed this one when it came out: Harry Potter and the Methods of Rationality. [HT: Aimee on the SciBlogs Google group]

Half-way down the first page, it started sounding an awful lot like Eliezer Yudkowsky. After this bit from the second chapter, it would have been shocking had it been anyone other than Eliezer.

The witch-lady was smiling benevolently upon them, looking quite amused. "Would you like a further demonstration, Mr. Potter?"
"You don't have to," Harry said. "We've performed a definitive experiment. But..." Harry hesitated. He couldn't help himself. Actually, under the circumstances, he shouldn't be helping himself. It was right and proper to be curious. "What else can you do?"
Professor McGonagall turned into a cat.
Harry scrambled back unthinkingly, backpedalling so fast that he tripped over a stray stack of books and landed hard on his bottom with a thwack. His hands came down to catch himself without quite reaching properly, and there was a warning twinge in his shoulder as the weight came down unbraced.
At once the small tabby cat morphed back up into a robed woman. "I'm sorry, Mr. Potter," said the witch, sounding sincere, though the corners of her lips were twitching upwards. "I should have warned you."
Harry was breathing in short gasps. His voice came out choked. "You can't DO that!""It's only a Transfiguration," said Professor McGonagall. "An Animagus transformation, to be exact."
"You turned into a cat! A SMALL cat! You violated Conservation of Energy! That's not just an arbitrary rule, it's implied by the form of the quantum Hamiltonian! Rejecting it destroys unitarity and then you get FTL signalling! And cats are COMPLICATED! A human mind can't just visualise a whole cat's anatomy and, and all the cat biochemistry, and what about the neurology? How can you go on thinking using a cat-sized brain?"
Professor McGonagall's lips were twitching harder now. "Magic."
"Magic isn't enough to do that! You'd have to be a god!"
Professor McGonagall blinked. "That's the first time I've ever been called that."
A blur was coming over Harry's vision, as his brain started to comprehend what had just broken. The whole idea of a unified universe with mathematically regular laws, that was what had been flushed down the toilet; the whole notion of physics. Three thousand years of resolving big complicated things into smaller pieces, discovering that the music of the planets was the same tune as a falling apple, finding that the true laws were perfectly universal and had no exceptions anywhere and took the form of simple maths governing the smallest parts, not to mention that the mind was the brain and the brain was made of neurons, a brain was what a person was -
And then a woman turned into a cat, so much for all that.

I'm enjoying this far more than I've enjoyed any part of the original Potter series (full disclosure: movies only, sorry). Watch especially for Harry's imagining how to arbitrage between Muggle-land and Hogwarts' where the latter runs a bimetalllic currency at a fixed exchange rate that differs from our price ratio. And fixing Quidditch.

The Last Ringbearer similarly dominates The Lord of The Rings. Hoorah for those authors (and their estates) who don't prosecute those creating fan faction!