An Open Thread: a place for things foolishly April, and other assorted discussions.

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Open Thread: April 2010
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[-]Baughn270

It doesn't seem like it's ever going to be mentioned otherwise, so I thought I should tell you this:

Lesswrong is writing a story, called "Harry Potter and the Methods of Rationality". It's just about what you'd expect; absolutely full of ideas from LW.com. I know it's not the usual fare for this site, but I'm sure a lot of you have enjoyed Eliezer's fiction as fiction; you'll probably like this as well.

Who knows, maybe the author will even decide to decloak and tell us who to thank?

My fellow Earthicans, as I discuss in my book Earth In The Balance and the much more popular Harry Potter And The Balance Of Earth, we need to defend our planet against pollution. As well as dark wizards.

-- Al Gore on Futurama

7Alicorn
I'm 98% confident it's Eliezer. He's been taunting us about a piece of fanfiction under a different name on fanfiction.net for some time. I guess this means I don't have to bribe him with mashed potatoes to get the URL after all. Edit: Apparently, instead, I will have to bribe him with mashed potatoes for spoilers. Goddamn WIPs.

Yeah, I don't think I can plausibly deny responsibility for this one.

Googling either (rationality + fanfiction) or even (rational + fanfiction) gets you there as the first hit, just so ya know...

Also, clicking on the Sitemeter counter and looking at "referrals" would probably have shown you a clickthrough from a profile called "LessWrong" on fanfiction.net.

Want to know the rest of the plot? Just guess what the last sentence of the current version is about before I post the next part on April 3rd. Feel free to post guesses here rather than on FF.net, since a flood of LW.com reviewers would probably sound rather strange to them.

"Oh, dear. This has never happened before..."

Voldemort's Killing Curse had an epiphenomenal effect: Harry is a p-zombie. ;)

I don't like where this is headed - Harry isn't provably friendly and they're setting him loose in the wizarding world!

Also, there is a sharply limited supply of people who speak Japanese, Hebrew, English, math, rationality, and fiction all at once. If it wasn't you, it was someone making a concerted effort to impersonate you.

7CronoDAS
Do I have to guess right? ;)
5Kevin
It gets a strong vote of approval from my girlfriend. She made it about halfway through Three Worlds Collide without finishing, for comparison. We'll see if I can get my parents to read this one... Edit: And I think this is great. Looking forward to when Harry crosses over to the universe of the Ultimate Meta Mega Crossover.
4Kevin
Let's make that a Prediction. Harry becomes the ultimate Dark Lord by destroying the universe and escaping to the Metametaverse of the Ultimate Meta Mega Crossover.
0[anonymous]
DO NOT want.
4Jack
This Harry is so much like Ender Wiggin.
2Cyan
Really? I picture him looking like a younger version of this.
[-]Jack120

This Harry and Ender are both terrified of becoming monsters. Both have a killer instinct. Both are much smarter than most of their peers. Ender's two sides are reflected in the monstrous Peter and the loving Valentine. The two sides of Potter-Evans-Verres are reflected in Draco and Hermione. The environments are of course very similar: both are in very abnormal boarding schools teaching them things regular kids don't learn.

Oh, and now the Defense Against the Dark Arts prof is going to start forming "armies" for practicing what is now called "Battle Magic" (like the Battle Room!).

And the last chapter's disclaimer?

The enemy's gate is Rowling.

If the parallels aren't intentional I'm going insane.

1NancyLebovitz
And going back a few chapters, I'm betting that what Harry saw as wrong with himself is hair-trigger rage.
0Cyan
Ooo, I missed that. Yeah, OK.
0[anonymous]
This Harry and Ender are both terrified of becoming monsters. Both have a killer instinct. Both are much smarter than most of their peers. Ender's two sides are reflected in the monstrous Peter and the loving Valentine. The two sides of Potter-Evans-Verres are reflected in Draco and Hermione. The environments are of course very similar: both are in very abnormal boarding schools teaching them things regular kids don't learn. Oh, and now the Defense Against the Dark Arts prof is going to start forming "armies" for practicing what is now called "Battle Magic" (like the Battle Room!). And the last chapter's disclaimer? If the parallels aren't intentional I'm going insane.
4Alicorn
There is a reason I didn't look for it. It isn't done. Having found it anyway via link above, of course I read it because I have almost no self-control, but I didn't look for it! Are you sure you wouldn't rather have the mashed potatoes? There's a sack of potatoes in the pantry. I could mash them. There's also a cheesecake in the fridge... I was thinking of making soup... should I continue to list food? Is this getting anywhere?
3Cyan
Holy fucking shit that was awesome.
2ShardPhoenix
This is a lot of fun so far, though I think McGonnagal was in some ways more in the right than Harry in chapter 6. Also, I kind of feel like Draco's behavior here is a bit unfair to the wizarding world as portrayed in the canon - the wizarding world is clearly not at all medieval in many ways (especially in the treatment of women where the behavior we actually see is essentially modern), so I'm not sure why it should necessarily be so in that way. Regardless of my nitpicking it's a brilliant fanfic and it's nice to see muggle-world ideas enter the wizarding world (which always seemed like it should have happened already).
2CronoDAS
You also have the approval of several Tropers, only one of which is me.
1Liron
I normally read within {nonfiction} U {authors' other works} but I had such a blast with Methods of Rationality that I might try some more fiction.
5MBlume
This story reminded me distinctly of Harry Potter and the Nightmares of Futures Past -- you might enjoy that one. Harry works until he's 30 to kill Voldemort, and by the time he succeeds, everyone he loves is dead. He comes up with a time travel spell that breaks if the thing being transported has any mass, so he kills himself, and lets his soul do the travelling. 30-year-old Harry's soul merges with 11-year-old Harry, and a very brilliant, very prepared, very powerful, and deeply disturbed young wizard enters Hogwarts.
1gwern
I've finished reading that. It's very well written technically - better than Eliezer who overindulges in speechifying, hyperbole, and italics - but in general Harry doesn't seem disturbed enough, heals too easily, and there are too few repercussions from his foreknowledge. (Snape leaving and usurping Kakaroff at Durmstang seems to be about it.) That, and the author may never finish, which is so frustrating an eventuality that I'm not sure I could recommend it to anyone.
2Kevin
AH... spoiler!
0gwern
Snape leaving is hardly a spoiler, since so far it hasn't affected anything...
0Alicorn
Similar in premise is "The Mirror of Maybe" (slash warning, never-updates warning) in which a fifth-year Harry is shown a hypothetical future and uses the extensive knowledge gained thereby to ditch school, disguise himself as an adult, and become the greatest Gary Stu of all time. Slightly AU magic system and, as I warned, it never freakin' updates.
-3Liron
lol
3Kevin
I like all of Eliezer's fiction... if you want more like this, see the pseudo-sequel, http://lesswrong.com/lw/18g/the_finale_of_the_ultimate_meta_mega_crossover/ It is too insane of a story to recommend to most people, but assuming you've read Eliezer's non-fiction, you can jump right in. Otherwise, just about all of Eliezer's fiction is worth reading, Three World's Collide is his best work of fiction.
0anonym
It's now the second hit on Google for (rationality + fiction)!
0arundelo
What proportion of the whole story are the current ten (nine) chapters likely to be? (There is going to be more, right? Right?!)

It's almost done, actually. Here's a sneak preview of the next chapter:

Dumbledore peered over his desk at young Harry, twinkling in a kindly sort of way. The boy had come to him with a terribly intense look on his childish face - Dumbledore hoped that whatever this matter was, it wasn't too serious. Harry was far too young for his life trials to be starting already. "What was it you wished to speak to me about, Harry?"

Harry James Potter-Evans-Verres leaned forward in his chair, looking bleak. "Headmaster, I got a sharp pain in my scar during the Sorting Feast. Considering how and where I got this scar, it didn't seem like the sort of thing I should just ignore. I thought at first it was because of Professor Snape, but I followed the Baconian experimental method which is to find the conditions for both the presence and the absence of the phenomenon, and I've determined that my scar hurts if and only if I'm facing the back of Professor Quirrell's head, whatever's under his turban. Now it could be that my scar is sensitive to something else, like Dark Arts in general, but I think we should provisionally assume the worst - You-Know-Who."

"Great heavens

... (read more)
3Kevin
that that is an excerpt or that you are almost done?
1Cyan
How proud of myself should I feel for figuring out how Comed-Tea works before Harry did? (Keeping in mind that it's been years since I internalized the facts that in the Harry Potter universe, prophecies work and Time-Turners don't create alternate time-lines, information not available to rational!Harry.)
2gwern
Not very. Tons of commentators glommed onto the non-time-warping explanation, and the fic all but tells us that this is a possibility, especially with the experiment vignette with Hermione on the train. (Personally, I don't like the idea that the Comed-Tea affects only Harry; that mechanism leaves Luna Lovegood as an ethically depraved libeller.)
2CronoDAS
Or her father, at least. (I think there was an author's note about this - she says vague things and he turns them into ridiculous headlines.)
0gwern
Well, that's just great - how am I supposed to know that now with Eliezer's little erasure system? I suppose better Xenophilius being a depraved libeller than Luna... although as an adult it's even more inexcusable.
3CronoDAS
I was looking over the old chapters and I found this:
1arundelo
Or just charmingly nutty.
0Cyan
Good to know.
1Baughn
And what does Voldemort have to do with anything? He's not Harry's target, he's just a stumbling block in the middle. You're not fooling me that easily. :P
7sketerpot
This Harry is so much more potentially powerful than canon Harry, therefore having canon Voldemort be the final boss would be a let-down. Eliezer's author description explicitly says that anything which strengthens the hero must be accompanied by a corresponding increase in the difficulties he will face, so I think we can be pretty confident that things are going to be much more awesome than just defeating Voldemort with the Potterverse equivalent of RPG rules exploitation.
1Psy-Kosh
Besides, even you had that happen in your story and had a dementor munching on the back of Quirrell's head, wouldn't the result be the equivalent of destroying only a single horcrux? (unless the bits of soul are linked in such a way that the dementor can suck them all up at a distance through the one...) You can't escape writing the rest of this that easily! ;) Also, hrm... would your comment here then count as you doing a parody fanfic of your own fanfic?
0Kevin
It could be one chapter where they debate whether or not to sic the dementor on Quirell without even confronting him, then one chapter where they figure out how to magically triangulate and destroy all of the Horcruxes at once.
4Psy-Kosh
Shhhh... Stop trying to make it easy for him to end the story sooner than later. ;) (Nevermind some of the grayer ethical aspects of, in a world with potentially eternal afterlife, Moldy Voldy's crimes may not stack up to that. (That is, "destroying a soul" >>> "killing someone" in the potter verse. Probably even "killing many someones" (otoh, IIRC the Dementor's were to a large extent his creatures, so we can probably safely assume that he was involved with or arranged for (or, more to the point, would in the future arrange for) plenty of soul consuming/destroying))
2LucasSloan
Well, by way of contrast, this point in the original book took us up to page 121 of 309. The story is currently 44,000 words which is approximately half the length of the average novel. However, we still haven't seen any deviation from the original story which suggests that Harry's opposition will be much harder, so I'm inclined to go with the first estimate, which gives us about 1/3 of total length so far. Not counting any sequels, of course.
0[anonymous]
Even if you'd used a different pseudonym and such, I'm sure a lot of us would have figured it out just from your writing style, the rationality explanations, and ... other things. Hell, the first chapter's disclaimer alone was a giveaway. :) Anyway, I've just finished reading all nine chapters, and this is a dream come true for me. I've had a few fantasies of my own about how I would have done things differently (and better / more rationally) if I'd been in Harry's shoes, and they were a lot like this fanfic... except for the sheer, scintillating brilliance of your work, I mean. This could be a good introduction/portal to rationality for a lot of people. I'll do what (little) I can to promote it and get you more readers, and I suggest other LWers do the same.
3Baughn
No, no, it's not Eliezer. It's an alternate personality, which acts exactly the same and shares memories, that merely believes it's Eliezer.
4Kevin
Sounds like an Eliezer to me.
5Larks
like an Eliezer, yes.
2Matt_Simpson
I know, right? This would have been a wonderful story for me to read 10 years ago or so, and not just because now I'm having difficulty explaining to my girlfriend why I spent friday night reading a Harry Potter fanfic instead of calling her...
6ata
Magnificent. (I've sent it to some of my friends, most of whom are thoroughly enjoying it too; many of them are into Harry Potter but not advanced rationalism, so maybe it will turn some of them on to the MAGIC OF RATIONALITY!) Edit: Sequel idea which probably only works as a title: "Harry Potter and the Prisoner's Dilemma of Azkaban". Ohoho! Edit 2: Also on my wishlist: Potter-Evans-Verres Puppet Pals.
1gwern
I could see that working as a prison mechanism, actually. Azkaban would be an ironic prison, akin to Dante's contrapasso. (The book would be an extended treatise on decision theory.) The reward for both inmates cooperating is escape from Azkaban, the punishment really horrific torture, and the inmates are trapped as long as they are conniving cheating greedy bastards - but no longer. (The prison could be like a maze, maybe, with all sorts of different cooperation problems - magic means never having to apologize for Omega.)
1pengvado
So if one prisoner cooperates and the other defects, then the defector goes free and the cooperator doesn't? That doesn't sound very effective for keeping conniving cheating greedy bastards in prison.
0gwern
I figure one would probably have to modify the dilemma to give sub-escape rewards to the defector. (I realize this inversion destroys the specific logical structure, but that's artistic license for you.)
1bogdanb
Four possible outcomes: stay in prison (maintain status quo), be released, be (mind)raped by a Dementor, or receive some chocolate. Distribute in the payoff matrix according to whatever Æsop you’re pushing to :-)
0Strange7
* Competitor gets chocolate, cooperator gets indirect dementor exposure. * Both compete, both severely dementor'd. * Both cooperate, both released, but bound together somehow.
0Strange7
What about making the prison a hedge-maze sort of area, with lots of controllable access-points? Points earned by interactions can be spent to give yourself temporary access through a specific gate, any given pair of prisoners can only play the game a certain number of times per day, and unspent points decay - say, 5% loss per day. To earn enough points to pay your way out the front door, you effectively have to have access to the whole interior, and be on good terms with most of the people there.
0gwern
The problem is that with 'currency' and iterated interactions like that, you start to approximate a concentration or POW camp, with considerable mingling and freedom, which allows bad'uns to thrive. At least, if my reading of literature about said camps (like World of Stone or King Rat) is anything to go by.
1Strange7
In that case, the points would have to be associated with a task rather than simply cooperation. Edit: also http://www.girlgeniusonline.com/comic.php?date=20070727
0gwern
Sure, that's reasonable. And it makes the prison/maze much more general - there could be all sorts of rationalist/moral traps in it, and then one could make the pure prisoner's dilemma the final obstacle before escape. I suppose the hard part is justifying in-universe the master rationalists who could create such a prison/maze - EY has clearly set Harry up in the fanfic as being the first master rationalist, and we can hardly postulate a hidden master when EY went to such pains with Draco to demonstrate the wizarding world's general moral bankruptcy (a hidden master would, one think, manage to bring the wizarding world up to at least muggle levels, if maybe not past it).
0wnoise
Why would one think that? This hidden master could be a total jerk-face.
0Strange7
Presumably Harry himself will be bringing about some drastic reforms. There's also the issue that wizards of the distant past might have been better rationalists than the current crop, but had less to work with, and the arts have simply been lost over time.
0gwern
That's not a bad idea. It actually works well - the general loss of wizarding power is then due not to any genetic dilution by mudbloods, but because they're ignorant or lazy. It goes a little against the LW grain (we despise Golden Age myths), but since Rowling insists on a wizarding Golden Age, it's a good subversion.
1NancyLebovitz
They don't have systems or habits for preserving knowledge reliably, and there's enough competition between wizards that a lot of the best spells (not to mention methods for developing powerful spells) won't be recorded, and might not even be taught.
0Strange7
Actually, genetic dilution might still be a factor... if the rationalism of the founders was imperfect, and they didn't know much about heredity, the inability of most people to duplicate magical feats might have been interpreted as the result of an error in those finicky incantations. Emphasis on rote memorization of reliable effects would then come at the expense of higher-level invention and item creation techniques. There are some possibly-relevant discussions of a history of magic in Tales of MU.
2gwern
You'll have to link them, then (unless you mean the very funny section about the science cultists); I read a bit of Tales of MU, but got weirded out after a while.
0Strange7
http://www.talesofmu.com/story/book0x/378 http://www.talesofmu.com/story/book0x/235
0RobinZ
The reference to King Rat) I can identify with an Internet search - what's World of Stone?
0gwern
Try "Tadeusz Borowski". Sample quotes: A (nonfiction) quote I sometimes think of in connection with World of Stone, though it's actually from The Captive Mind, is:
4Unnamed
Harry Potter as a boy genius smart-aleck aspiring rationalist works surprisingly well. And the idea of extending the pull of rationalism a bit beyond its standard sci-fi hunting grounds using Harry Potter fanfiction is brilliant.
1Document
For the record, it's currently the first Google autocomplete result for "harry potter and the me", with apparently multiple pages of forum posts and such about it.
0[anonymous]
So people get really invested in this fan-fiction stuff, huh?
1LucasSloan
Fb, sebz gur cbvag bs ivrj bs na Nygreangr-Uvfgbel, V nffhzr gur CBQ vf Yvyyl tvivat va naq svkvat Crghavn'f jrvtug ceboyrz. Gung jbhyq graq gb vzcebir Crghavn'f ivrj bs ure zntvpny eryngvirf, naq V nffhzr gur ohggresyvrf nera'g rabhtu gb fnir Wnzrf naq Yvyyl sebz Ibyqrzbeg. Tvira gur infgyl vapernfrq vagryyvtrapr bs Uneel, V nffhzr ur vf abg trargvpnyyl gur fnzr puvyq jr fnj va gur obbxf, nygubhtu vzcebirq puvyqubbq ahgevgvba pbhyq nyfb or n snpgbe.
0Baughn
Not having the same father would tend to imply not being genetically the same, yes. This isn't the Harry Potter we know.
4AdeleneDawner
He does have the same genetic parents; it's his biological aunt, not his biological mother, who married someone different in this timeline.
2Baughn
I feel rather foolish now. Of course he does. Should still be a genetic reshuffling, at least. The point of departure seems to be before his birth, so the butterfly effect would be in effect.
1Vladimir_Nesov
The probability of magic should make any effort on testing the hypothesis unjustified. Testing theories no matter how improbable is generally incorrect dogma. (One should distinguish improbable from silly though.)

I think you underestimate the real-world value of Just Testing It. If I got a mysterious letter in the mail and Mom told me I was a wizard and there was a simple way to test it, I'd test it. Of course I know even better than rationalist!Harry all the reasons that can't possibly be how the ontologically lowest level of reality works, but if it's cheap to run the test, why not just say "Screw it" and test it anyway?

Harry's decision to try going out back and calling for an owl is completely defensible. You just never have to apologize for doing a quick, cheap experimental test, pretty much ever, but especially when people have started arguing about it and emotions are running high. Start flipping a coin to test if you have psychic powers, snap your fingers to see if you can make a banana, whatever. Just be ready to accept the result.

2Vladimir_Nesov
This (injunction?) is equivalent to ascribing much higher probability to the hypothesis (magic) than it deserves. It might be a good injunction, but we should realize that at the same time, it asserts inability of people to correctly judge impossibility of such hypotheses. That is, this rule suggests that probability of some hypothesis that managed to make it in your conscious thought isn't (shouldn't be believed to be) 10^-[gazillion], even if you believe it is 10^-[gazillion].
2bogdanb
I guess it depends a bit on how you came to consider the proposition to be tested, but I’m not sure how to formalize it. I wouldn’t waste a moment’s attention in general to some random person proposing anything like this. But if someone like my mother or father, or a few of my close friends, suddenly came with a story like this (which, mark you, is quite different from the usual silliness), I would spend a couple of minutes doing a test before calling a psychiatrist. (Though I’d check the calendar first, in case it’s April 1st.) Especially if I were about that age. I was nowhere near as bright and well-read rationalist!Harry at that age (nor am I now). I read a lot though, and I had a pretty clear idea of the distinction between fact and fiction, but I remember I just didn’t have enough practical experience to classify new things as likely true or false at a glance. I remember at one time (between 8 and 11 years old) I was pondering the feasibility of traveling to Florida (I grew up in Eastern Europe) to check if Jules Verne’s “From the Earth to the Moon” was real or not, by asking the locals and looking for remains of the big gun. It wasn’t an easy test, so I concluded it wasn’t worth it. However, I also remember I did check if I had psychic powers by trying to guess cards and the like; that took less than two minutes.
2RobinZ
The probability that you have no grasp on the situation is high enough to justify an easy, simple, harmless test. And I'd appreciate it if spoilers for the story were ROT13'd or something - I haven't read it.
5Kevin
You mean the plot point that Harry Potter tested the Magic hypothesis? I don't think most plot points in the introductions of stories really count as spoilers.
2CronoDAS
Yeah, that's not a spoiler any more than "Obi-Wan Kenobi is a Jedi" is a spoiler.

A "Jedi"? Obi-Wan Kenobi?

I wonder if you mean old Ben Kenobi. I don't know anyone named Obi-Wan, but old Ben lives out beyond the dune sea. He's kind of a strange old hermit.

0RobinZ
Ah, of course. That's fine, then. Although you might want to let EY know that someone posted unobfusticated spoilers for ... Chapter 10, was it? - in violation of community standards. ;)
0ShardPhoenix
I agree, though I think the particular test chosen in the story didn't make much sense - even if magic was real I wouldn't have expected that to have any effect.
1RobinZ
The most astonishing thing about spoilers, I find, is that they are often provided to you with exactly as much enthusiasm after you announce that you haven't seen the story as before.
1wnoise
This isn't surprising at all. People who give out spoilers when discussing a work generally don't care that you don't like to hear spoilers before you've experienced a work.
0ShardPhoenix
Considering you've read the rest of the posts in this thread, that's not a spoiler, just my opinion about what you've already been discussing.
0RobinZ
I haven't.
2ShardPhoenix
Well, it was a bit silly to comment on it without context then. At any rate no major/obvious spoilers have been posted here.
0RobinZ
That's a relief.
4Baughn
It was strongly implied that some element of Harry's mind had skewed that prior dramatically. Perhaps his horcrux, perhaps infant memories, but either way it wasn't as you'd expect. Even for an eleven-year-old.
0Vladimir_Nesov
He didn't bite the bullet, didn't truly disbelieve his corrupted hardware. This is a problem that has to be solved by introspection, better theory of decision-making. It's not enough to patch it by observation in each particular case, letting the reality compute a correct conclusion above your defunct epistemology, even when you have all the data you might possibly need to infer the conclusion yourself.
1Mass_Driver
Why not? I mean, granted, there might be occasions when you need the ability to disbelieve your hardware, but I'm having trouble thinking of any. It's unlikely enough that you'll go crazy; it's still more unlikely that you'll go crazy in such a way that your future depends on immediately and decisively noticing that you're mad. if you enjoy running tests and have the resources for it, why not indulge?
1Vladimir_Nesov
I'm talking about not interpreting intuitive "feel" for a belief as literally representing consciously endorsed level of belief. It's perfectly normal for your emotion to be at odds with your beliefs (see scope insensitivity for example). This kind of madness doesn't imply being less functional than average. We are all mad here. If you feel that "magic might be real", but at the same time believe that "magic can't be real, no chance", you shouldn't take the side of the feeling. The feeling might constitute new evidence for your beliefs to take into account, but the final judgment has to involve conscious interpretation, you shouldn't act on emotion directly. And sometimes, this means acting against emotion (intuitive expectation). In this case in particular, intuition is weak evidence, so it doesn't overpower a belief that magic isn't real, even if it's strong intuition.
0bogdanb
Do you realize how many catgirls were killed because of you today?
3Matt_Simpson
One of the goals was to get his parents to stop fighting over whether or not magic was real.
1Vladimir_Nesov
How would it work? As expected outcome is that no magic is real, we'd need to convince the believer (mother) to disbelieve. An experiment is usually an ineffective means to that end. Rather, we'd need to mend her epistemology.
3Matt_Simpson
Well, Harry did spend some time making sure that this experiment would convince either of his parents if it went the appropriate way, though he had his misgivings. As a child who isn't respected by his parents, what better options does he have to stop the fight? (serious question)
0Vladimir_Nesov
Having no good options doesn't make the remaining options any good. This is a serious problem, for example, when people try to explain apparent miracles they experience: they find the best explanation they are able to come up with, and decide to believe that explanation, even if it has no right to any plausibility, apart from the fact it happened to be the only one available.
0Matt_Simpson
So you think that the best response is to do nothing about the fight. Perhaps, but setting up the experiment didn't take that much effort. What was Harry's opportunity cost here? Is it that high?
0Vladimir_Nesov
It's not completely out of the question that it was a fine rhetorical effort (though it's not particularly plausible), but it's still not concerned with finding out the truth, which was presented as the goal.
2Matt_Simpson
There seemed to be two goals to me - finding the truth and stopping the fight. I'll have to reread that section later.
0[anonymous]
A valid point.
2Alicorn
You have not taken into account that testing magical hypotheses may be categorized as "play" and pay its rent on time and effort accordingly.
2Vladimir_Nesov
Then this activity shouldn't be rationalized as being the right decision specifically for the reasons associated with the topic of rationality. For example, the father dismissing the suggestion to test the hypothesis is correct, given that the mere activity of testing it doesn't present him with valuable experience. You've just taken the conclusion presented in the story, and wrote above it a clever explanation that contradicts the spirit of the story.
0CronoDAS
Wow, I wish I saw this sooner. And there are already 99 pages of reviews! ETA: Wow, now there's 100...
[-]Zubon210

Example of teachers not getting past Guessing the Teacher's Password: debating teachers on the value of pi. Via Gelman.

4Eliezer Yudkowsky
AAAAAIIIIIIIIEEEEEEEE BOOM
8Alicorn
Clearly, your math teacher biting powers are called for.
3CronoDAS
In first grade, I threw a crayon at the principal. Can I help? ;)
3JGWeissman
Let's not get too hasty. They still might know logarithms. ;)
3Tyrrell_McAllister
It would have been even more frustrating had the protagonist not also been guessing the teacher's password. It seemed that the protagonist just had a better memory of what more authoritative teachers had said. The protagonist was closer to being able to derive π himself, but that played no part in his argument.
8JGWeissman
The protagonist knew that pi is defined as the ratio of a circle's circumference and diameter, and the numbers that people have memorized came from calculating that ratio. The protagonist knew that pi is irrational, that irrational means it cannot be expressed as a ratio of integers, and that 7 and 22 are integers, and that therefore pi cannot be exactly expressed as 22/7. The protagonist was willing to entertain the theory that 22/7 is a good enough approximation of pi to 5 digits, but updated when he saw that the result came out wrong.
-3Tyrrell_McAllister
These are important pieces of knowledge, and they are why I said that they protagonist was closer to being able to derive π himself. The result only came out wrong relative to his own memorized teacher-password. Except for his memory of what the first five digits of π really were, he gave no argument that they weren't the same as the first five digits of 22/7.