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Harry Potter and the Methods of Rationality discussion thread, part 20, chapter 90

9 Post author: palladias 02 July 2013 02:13AM

This is a new thread to discuss Eliezer Yudkowsky’s Harry Potter and the Methods of Rationality and anything related to it. This thread is intended for discussing chapter 90The previous thread has passed 750 comments. 

There is now a site dedicated to the story at hpmor.com, which is now the place to go to find the authors notes and all sorts of other goodies. AdeleneDawner has kept an archive of Author’s Notes. (This goes up to the notes for chapter 76, and is now not updating. The authors notes from chapter 77 onwards are on hpmor.com.) 

The first 5 discussion threads are on the main page under the harry_potter tag.  Threads 6 and on (including this one) are in the discussion section using its separate tag system.  Also: 1234567891011121314151617,18,19.

Spoiler Warning: this thread is full of spoilers. With few exceptions, spoilers for MOR and canon are fair game to post, without warning or rot13. More specifically:

You do not need to rot13 anything about HP:MoR or the original Harry Potter series unless you are posting insider information from Eliezer Yudkowsky which is not supposed to be publicly available (which includes public statements by Eliezer that have been retracted).

If there is evidence for X in MOR and/or canon then it’s fine to post about X without rot13, even if you also have heard privately from Eliezer that X is true. But you should not post that “Eliezer said X is true” unless you use rot13.

Comments (609)

Sort By: Controversial
Comment author: Coscott 03 July 2013 09:26:06PM 1 point [-]

Theory: Harry learns how to make a horcrux, goes back 6 hours, takes the marauder's map to find Hermione causing him to have to oblviate Fred and George, Makes Hermione a horcrux before she dies.

Perhaps he even gets around the sacrifice requirement by letting Hermione's own death be the sacrifice.

Comment author: Alsadius 04 July 2013 03:56:56AM 4 points [-]

1) I see no way Harry can learn horcrux magic in six hours.

2) I cannot imagine Harry using her death as a resource. For all that he talks about using all resources he can, trhat would be a bridge too far for him, I suspect.

Comment author: linkhyrule5 04 July 2013 04:42:51AM 2 points [-]

Using her death to resurrect her might not be beyond him, though.

Though the idea has other problems (part 1, and also that Horcrux magic, as far as we know, requires you to split your own soul.)

Comment author: Alsadius 04 July 2013 05:18:37AM 2 points [-]

So he would go back in time, teach her horcrux magic, and use her own death to split her own soul so that she can later be resurrected?

Comment author: Tenoke 02 July 2013 02:49:11PM *  1 point [-]

Meaning to post this for a while not because it is a novel idea but just so it is recorded somewhere.

I think that there is a good chance that the story finishes with A SuperIntelligence of sorts. Furthermore, I think that if a SI is actually brought in the story, there is at least 50% chance that it will be a SI built/cast with good intentions which nonetheless destroys (in a way) humanity and/or the universe.

Comment author: Pentashagon 03 July 2013 12:25:24AM 1 point [-]

What is Magic besides some form of superintelligence, or at least the remnants of superintelligence? The strongest evidence is that magic-users and even creators don't really have to understand how the spells actually work in order to use them. There is information entering the system from somewhere, and it's enough information to accurately interpret the vague wand movements and sounds of humans and do sufficiently amazing things without too many chaotic side-effects. Even the chaotic side-effects are usually improbably harmless. It's like an almost-Friendly, or perhaps a broken previously-Friendly, AI. Possibly the result of some ancient Singularity that is no longer explicitly remembered.

Comment author: Eugine_Nier 04 July 2013 05:01:07AM 3 points [-]

The strongest evidence is that magic-users and even creators don't really have to understand how the spells actually work in order to use them.

You don't need to know how muscles work in order to use them to move.

Comment author: [deleted] 04 July 2013 07:59:27AM 0 points [-]

You also don't need to know how algorithms work in order to use them, or even to write them. I don't know how Ukkonen's algorithm works, but I've implemented it. You haven't seen magic until you've seen the suffixes of a string sorted in linear time.

Comment author: ygert 03 July 2013 10:17:10AM 2 points [-]

Eliezer specifically and publicly said that this will not happen. There will be no superintelligent AI in HPMOR. I see no reason to doubt Eliezer's word on the matter.

Comment author: loserthree 03 July 2013 12:42:59PM 3 points [-]

I'm pretty sure that what he said was that nothing was intended as an allegory -- or maybe a metaphor or something of the sort -- to an artificial super-intelligence.

Somebody has the link, I expect.

Comment author: Tenoke 03 July 2013 05:58:06PM 2 points [-]

fair enough

Comment author: Qiaochu_Yuan 02 July 2013 06:20:43PM 3 points [-]

Doubtful. I think people would complain about HPMoR becoming too transparently an Author Tract in that case.

Comment author: JoshuaZ 02 July 2013 06:33:48PM 4 points [-]

Keep in mind that is already one of the more common criticisms of the story.

Comment author: Qiaochu_Yuan 02 July 2013 07:57:00PM *  9 points [-]

I guess by "too transparently" I mean the following. The worst kind of author tract is when an author shoehorns in some point they want to make in a way that has nothing to do with and distracts from the rest of the story. We already know that HPMoR is about rationality and whatnot - it's exactly what it says on the tin in that respect - but nothing in the story so far suggests the later appearance of a superintelligence, and if one were to appear it would feel shoehorned in.

Comment author: ChristianKl 04 July 2013 09:42:51PM *  0 points [-]

The plan to resurrect Hermonine might be:

(1) Take her body back in time via the time turner and replace her.

(2) Kill another student that Dumbledore gets the feeling that a student died.

Comment author: linkhyrule5 02 July 2013 07:55:58PM 1 point [-]

I asked the Headmaster to go back and save Hermione and then fake everything, fake the dead body, edit everyone's memories, but Dumbledore said that he tried something like that once and it didn't work and he lost another friend instead.

This sentence is interesting - not least because I had previously assigned a high probability to this being his method of resurrection, but also because it potentially tells us interesting things about time and death in the MoR-verse.

... I'm not entirely sure what, though. That last bit, in particular, that someone else died too when he tried...

Comment author: shminux 02 July 2013 08:10:15AM 1 point [-]

Is Harry's Patronus 2.0 out of the bag now?

Comment author: Decius 02 July 2013 09:15:30PM 2 points [-]

No. The twins know how to keep a secret, even from themselves. Perhaps too well from themselves.

Comment author: Ritalin 02 July 2013 06:43:36PM 1 point [-]

Presumably not, modulo memory charms.

Comment author: shminux 02 July 2013 06:58:18PM 1 point [-]

Well, he mentions it casually to McGonagall, who did not see it before:

If I'd remembered the Patronus earlier!

Comment author: linkhyrule5 02 July 2013 07:33:02PM 1 point [-]

All that tells her is that he figured out the Patronus somehow. She doesn't know that there's a 2.0 version.

Neither do F&G, really; it's unique and humanoid, but the real secret is that it kills (un-kills?) Dementors.

Comment author: monsterzero 06 July 2013 01:09:29AM 1 point [-]

The real secret is that once you know why it works, you can never cast Patronus 1.0 again. The humanoid form is a clue, so Harry needs to conceal it.

Killing Dementors is awesome, but in the short term the benefit of showing that ability off does not outweigh the risk of leaving all wizards everywhere defenseless against them.

Comment author: kilobug 03 July 2013 08:12:35AM 2 points [-]

I've been wondering about how the Hogwarts wards work. It seems quite contradictory to me that they need a complex setup with a spell killing Draco very slowly to not trigger them, but they aren't triggered when Hermione is critically wounded by having her two legs eaten. If there is a ward warning Dumbledore or the teacher staff when a student is in danger, then Hermione would have been saved, by Dumbledore phoenix-travelling to her before her death (or McGonagall sending a Patronus to Dumbledore so he phoenix-travels if only the teachers within Hogwarts are warned).

Comment author: alex_zag_al 04 July 2013 01:10:36AM 3 points [-]

Sure, imagine that whoever killed Draco just did it by cutting off his legs. He would die, Dumbledore would arrive, and catch him. No way to avoid it - Dumbledore can use the time-turner to watch the murder.

The point of evading the wards isn't to ensure the success of the hit, it's to make sure that nobody hears about the death until the six-hour limit hides the murder.

Both Hermione's death and the complex setup used to kill Draco are consistent with wards that respond only to death.

Comment author: kilobug 04 July 2013 07:55:23AM 4 points [-]

Chapter 79 says clearly : « The clear intent of the Blood-Cooling Charm had been to kill Draco Malfoy so slowly that the wards of Hogwarts, set to detect sudden injury, would not trigger. » So... why didn't the wards detect "sudden injury" when Hermione legs were eaten ?

Comment author: jsalvatier 05 July 2013 07:22:21PM 2 points [-]

Which brings up the question: has Dumbledore use his time-turner to observe who let the troll in?

Comment author: Izeinwinter 03 July 2013 11:25:32AM 10 points [-]

The workaround used on Draco could credibly be the work of a hogwarts student. That was needed because it was intended to be blamed on Hermione. The hit on Hermione did not have that constraint -it is blatantly, obviously, undeniably, the work of a master wizard. The fact that the wards were fucked with is just one stone in the pile of evidence that this was not the work of a fellow student with a grudge, but the work of someone like Bellatrix, Lucius,Voldemort, or a highly competent wand-for-hire.

Comment author: Benquo 02 July 2013 07:23:33PM *  2 points [-]

"In any case," said the man, "if there is anyone who can be said to be responsible for Miss Granger's death, it is myself, not you. It is I, not you, who should have -"

"I perceive that you have spoken to Professor McGonagall and that she has given you a script to follow." The boy did not bother keeping the bitterness from his voice. "If you have something to say to me, Professor, say it without the masks."

My confidence that Quirrel did it just shot up from 90% to 99%.

Comment author: loserthree 02 July 2013 03:27:32AM 2 points [-]

It'd been one of the spells he and Hermione had experimented on, a lifetime ago, so he was able to control it precisely, though it had taken a lot of power to affect that much mass. Hermione's body should now be at almost exactly five degrees Celsius.

I feel like this comes off as a bit of an ass pull. It's the suspicious specificity that does it, I think.

It would be easy to prevent that feeling, if you care to and if it's not just me, with a throwaway line in an earlier chapter.

Comment author: Alsadius 02 July 2013 04:16:19AM 4 points [-]

A cryonics fanboy writing a story about a cryonics fanboy with access to a spell that can freeze a corpse? Specificity is to be expected.

Comment author: linkhyrule5 02 July 2013 02:45:47AM 3 points [-]

"Or if I'd - if I'd only gone with - if, that night -"

Which night is this? Are we talking about Draco here?

Comment author: purpleposeidon 02 July 2013 09:06:16PM 4 points [-]

The narration in chapters 88 and 89 have left quite a bit of room for Weasley Twin shenanigans. They are referred to as "the twins" and "Fred or George" up until one gets beat up by the troll. Additionally, the twins gave a respectful nod to McGonagall's demand that they stay in the Great Hall; they could have stayed there the entire time. Harry might have been accompanied by, say, Future Fred and Further Future Fred during his broom flight. I am not sure what the use of this would be, but it might involve them being a hive mind.

Comment author: cody-bryce 02 July 2013 11:49:34PM 6 points [-]

They gave a respectful nod because they are smartasses.

Comment author: Sheaman3773 24 August 2013 04:29:34AM 2 points [-]

...what? They have a respectful nod because they recognized the seriousness of the situation, that it was not a time for pranks.

They only left when the situation got more serious yet, and they pseudo-remembered that they could help.

Comment author: purpleposeidon 03 July 2013 07:32:54AM *  9 points [-]

This has got me quite convinced that Fred and Fred is going to happen. They are probably connected magically, rather than acoustically, so they might be able to communicate across time. This setup might create the time beacon Harry was wanting.

Or, maybe their connection does not link through time. Send a pair of Weasleys back in time. You now have 4 Weasleys. Wait not-quite-an-hour, and then send 4 Weasleys back in time… 4 Weasleys is twice the number of Weasleys. Are N Weasleys N/2 times as smart as 2 Weasleys? No. It is much more interesting if it is the connections that matter. HE is the Weasley hivemind.

Comment author: chrisfarms 03 July 2013 12:09:06PM 9 points [-]

There was an off-the-cuff line back in Ch25:

Back in the old days, whenever magical identical twins were born, it had been the custom to kill one of them after birth.

I wonder if there is something more to a magical twin connection, that may have even caused problems (confusing the source of magic?), or if this was just a comment on how dark/backwards things were in the old days.

Comment author: linkhyrule5 03 July 2013 08:44:27PM 0 points [-]

I think it was mostly something along the lines of "there's no point, you're just going to have two of the same person."

Comment author: Velorien 03 July 2013 09:20:05PM 1 point [-]

One does not customarily kill newborn children merely because they're "unnecessary".

Comment author: Ritalin 04 July 2013 07:08:51AM 2 points [-]

Preislamic arabs were infamous for that kind of post-birth birth control. Romans also practiced the same thing: a roman had the right and privilege to kill his descent whenever and however he saw fit. So, it's customary when it's customary.

Comment author: gjm 03 July 2013 09:09:32AM 1 point [-]

Upvoted because, although I'm about 99.9% sure it's not remotely what Eliezer has in mind, it's a lovely idea.

Comment author: ikrase 02 July 2013 10:37:30AM 5 points [-]

Came up with an idea of a method to ressurrect Hermione.

  1. Cnvag n cvpgher bs Urezvbar
  2. Nfx vs fur vf frys-njner.
Comment author: Mestroyer 02 July 2013 01:04:15PM 9 points [-]

Brute force method:

  1. Precommit to create a paradox if whatever arranges time in consistent loops doesn't give you what you want.
  2. If you don't get what you want, receive a red or green slip of paper from your future self. Use time turner, hand to your past self whatever color of paper you didn't get. If you find that the paper has "Do not mess with time" on it, for the slip you hand to your past self, instead write "Fuck you, time."
  3. Discover secrets of Atlantis, hack time travel, etc.

    The problem with this is that time can adjust to avoid the paradox at any point in the timeline, which means that if you are a person who would try to exploit this, the sperm that would have created you was outraced by another one. So perhaps existing depends on not using this. (Parfit's Hitchhiker)

Comment author: Ritalin 02 July 2013 06:39:34PM 2 points [-]

DO NOT MESS WITH TIME

Comment author: Alejandro1 02 July 2013 02:25:34PM 16 points [-]

Or, if you try to use this and commit to be really serious about it, you get struck by a meteorite before completing the paradox. Or slip on a banana peel and bash your head. Or a get mauled by a troll. Some external cause comes in and prevents you from fulfilling your paradox.

Comment author: Will_Newsome 03 July 2013 01:42:11AM 4 points [-]

Or you never come up with the idea in the first place.

Comment author: Mestroyer 03 July 2013 03:30:07AM 3 points [-]

Or abiogenesis never happened in the first place. That seems a lot simpler than nudging tons of different humans later.

Comment author: ChristianKl 02 July 2013 09:33:26PM 1 point [-]

That method would resurrect something but not the real Hermione.

Comment author: Ritalin 02 July 2013 07:45:25PM 11 points [-]

Last chapter I complained about EY having hermione Stuffed Into The Fridge, i.e. unceremoniously killed offscreen to provide motivation for the main character. Today I find that he is literally refrigerating her!

Comment author: David_Gerard 03 July 2013 08:41:24PM 1 point [-]

Imagine a cryonics enthusiast writing about a cryonics enthusiast making the explanation of his move a pun on a trope name ;-)

Comment author: tondwalkar 04 July 2013 03:51:14AM *  6 points [-]

i.e. unceremoniously killed offscreen

nitpick: Hermionie wasn't just killed onscreen, she was front and center.

Comment author: shminux 02 July 2013 08:09:26AM 6 points [-]

Who are the (remaining) PCs in the story? Harry, Dumbledore, Quirrell, Moody... Anyone else?

Comment author: CAE_Jones 02 July 2013 04:12:54AM 6 points [-]

Curious; when I read Professor Quirrel going into "protect the information from Harry Potter" mode for Macgonnagle, I almost immediately thought this was deeper than "I've changed my mind and it is no longer a good day and holyshit he's going to kill us". The overwhelming majority of readers assume he is being sincerely cautious in an effort to save the universe. I was assuming that there was obviously a slightly deeper plot involved, though I hadn't gotten far in thinking about what before I read the suggestions about alternative sources such as the Chamber of Secrets.

(Harry's lecture to Macgonnagle on identity-based strategy actually made me realize something about myself I feel is worth analysis... somewhere. I may or may not get back on that if I figure out if it's worth publishing.)

Comment author: mare-of-night 02 July 2013 10:00:51PM 1 point [-]

In light of all the talk about heroic responsibility, my first thought was that if he really, really wanted Harry kept away from those books, he'd steal them or something. (This specific method isn't a very good one because it would raise suspicion, but there has to be a better way to keep them from Harry than going through Macgonnagle.) And maybe he was hoping that Harry would notice the increased wards and try to go there because of it, but that seems like he might be assuming too much.

Comment author: kilobug 04 July 2013 11:45:26AM 8 points [-]

After reading 91 and 92, I'm almost certain that we weren't told something very important about what Harry did from the death of Hermione to the end of chapter 92. I just can't believe Harry Potter, the one who would raze Azkaban at the cost of his life before seeing Hermione send to it would just accept her death and not try to do the impossible again and again to save her. He even swore to "torn apart the fabric of reality" if it's required to help her.

And yet, there are dozens of things he could have tried but apparently didn't try. He didn't try to replace the "oxygenation potion" with a different potion, and when he faced Snape, he didn't even ask Snape if there would be any potion that could be useful. When he met his father, a skilled biochemist, he didn't ask him anything about how to preserve brains. He didn't ask Quirrell if there was a ritual that could freeze Hermione (either cryonics-like, or a kind of temporal stasis) until he discovers a way of resurrecting her. He didn't ask McGonagall if there would be a way to transmute her brain into a diamond-like or whatever substance that would keep the configuration of her brain stable in time. He didn't try to get Hermione to Alcor.

He didn't even try to use his time-turner just to get more time to think and try to find solutions, according to what we were given to read.

So, either he's just so full of pain that he's broken and unable to think, but it doesn't seem at all like that, or he must have tried many other things, much better than those few ideas (some which I got from the comments here). And if he didn't ask anyone for help, while he usually does when needed, it's because he already knew what to do.

Comment author: cywtLC2Fy8A 02 July 2013 02:48:14PM *  13 points [-]

Multiple FF.net reviews suggest getting Harry's parents to try and cheer him up. But what about this, before the beginning of chapter 1:

Petunia married a biochemist

I predict Harry might realise his father can help him and find a way to ask/make him help. All the PCs and powerful NPCs around him want Hermione to be dead (either through action or inaction). If she can be revived, a professor of biochemistry might just have relevant knowledge, equipment, and the will to act. Come to think of it, even more so might Hermione's parents.

The biggest problem I see with this is that in the past, Harry felt his father did not take him seriously. However, he now has power his father knows not, and he has resolved to do anything to bring her back - he could credibly threaten his father's career, for example.

The second problem is that Harry may be too wrapped up with being responsible and needing to fix this himself to think of asking anyone else for help, but signalling him via Patronus is at least worth a try and costs little - "We are in a war situation, my best friend was just killed by a double traumatic leg amputation, but I've cooled her to 5 degrees and trying to work out what to do next. Ideas? I am deadly serious."

Comment author: drethelin 02 July 2013 05:11:24PM 23 points [-]

you're uh, assigning just a tad too much power to the average biochemist.

Comment author: asr 02 July 2013 05:16:10PM 16 points [-]

Professor Evans-Veres is at Oxford, so he's probably a well-above-average biochemist.

Bear in mind that the question isn't "can top biochemistry professors help stop/undo death" -- it's "can a high-end biochemist be of help, if you can do magic and rearrange matter at the molecular level." And that seems relatively plausible.

Comment author: NancyLebovitz 03 July 2013 12:40:54AM 2 points [-]

Getting his father (or just about anyone) up to speed enough to be able to help within the six hour window seems unlikely. The problem isn't motivation.

Comment author: ChristianKl 02 July 2013 09:29:47PM 2 points [-]

Could you propose a specific way that a high-end biochemist can help with the condition in which Hermoine happen to be?

Comment author: William_Quixote 02 July 2013 07:09:43PM *  19 points [-]

you're uh, assigning just a tad too much power to the well above average biochemist.

More seriously, I think Harry's path here is much more magic than bio focused. He's seen memories removed and copied. If he can figure out how to remove ALL the memories from a body, and if he knows the obliviate charm, and if dead cells work for poly juice (which they should since hair is dead) then he has a decent path using only minor variants to known magic.

Comment author: atorm 03 July 2013 03:30:19PM 1 point [-]

Hair isn't even cellular. Given that it can be cut off and used, follicles are not required.

Comment author: maia 02 July 2013 09:14:38PM 3 points [-]

But the way memories are stored in Pensieves, all they provide is a firstperson video feed of things that have happened. That's not enough information to make up a whole person.

Comment author: William_Quixote 03 July 2013 02:02:10AM 4 points [-]

Is it first person video, or first person full sense feed (including sound smell, feel of the chair etc.)? Because if its a first person full sense feed, plugging that into human brains is how we get people right now.

If you push the same feed into a brain, you might get the same person at the end. I'll note that the Mr. Bester storyline makes a point of showing how reproducible thoughts are given the same conditions.

Comment author: solipsist 08 July 2013 10:34:19PM *  14 points [-]

Here's how I would have saved Hermione if I were Harry.


In an accessible but seldom visited hallway of Hogwarts, a rail-way sign reads 6PM to 5PM Express.

At 5:00, a boy materializes under the sign. He is wearing a rail-way conductor's hat. He is holding a trunk. His name is Harry Potter.

Conductor Harry puts down the trunk. He opens the lid. Inside his Trunk of Holding are wooden seats numbered 1 through 1000. All seats appear to be empty.

Conductor Harry yells "Arriving at 5PM! Please add one tally to your forearm now".

Silently, hundreds of people draw a tally mark on their arms.

Conductor Harry steps away from the trunk and the hundreds invisible passengers of the 6PM to 5PM Express disembark.

At 5:10, Conductor Harry closes the trunk lid. He stashes the trunk [EDIT] and Time-Turner in the Great Hall.

At 5:12, Conductor Harry burns his conductor hat. He draws one tally mark on his previously blank arm, and puts on his invisibility cloak. He sighs. He has a long day ahead of him.

...

At 5:30 in the Astronomy Tower, a smelly and disheveled Harry Potter pulls off his invisibility cloak. He is covered with hundreds of tally marks, and looks like he hasn't slept in days. He yells "Screw this, I'm done!", collapses on the floor, and falls asleep.

...

At 5:40, the original Harry goes to his room. He has done no time traveling today, and has no tally marks on his arm.

Original Harry locates his trunk and his conductor's hat.

At 5:45, Original Harry brings his trunk and hat to the hallway with a 6PM to 5PM Express sign.

At 5:50, Original Harry puts on his conductor's hat. Harry -- now Conductor Harry -- opens the trunk, steps aside, and yells "All aboard the 6PM to 5PM Express!. Please go to your assigned seat."

Hundreds of invisible Harrys silently climb into the trunk. Each Harry counts the tallies on his arm and sits in the corresponding seat.

At 5:59, conductor Harry yells "Last Call for the 6PM to 5PM Express!"

At 6:00, conductor Harry closes his trunk. He picks up his trunk, and flips his time-turner.


Using this method, Harry can get as much time as he wants to study obliviation, transfigure large objects, or anything else, all with a single twist of his time turner. That's more than enough time to learn to obliviate yourself (and maybe the Weasley) and fake Hermione's death.

Comment author: EternalStargazer 10 July 2013 04:50:33AM 2 points [-]

Well, he can get as much time as he wants in 40 minute intervals with no breaks in between. Smelly Harry must have been awake at least 1 hour per mark on his arm, unless he has at some point mastered Polyphasic sleep (which is completely contrary to his aberrant sleep cycles as mentioned previously) he is going to be significantly diminished in terms of mental acuity after a mere 24 or so cycles. He would need to spend a few cycles eating. After subjective days without sleep he should be moving into hallucination territory, barring some kind of magical aid. His "useful time" is only between 5:10-5:50 on each cycle, at other times he will be boarding or leaving the express.

It's a moderately good hack, but it isn't of infinite versatility, barring the addition of a bit more cheating to get around the sleep/food problems.

Comment author: solipsist 10 July 2013 05:14:35PM *  5 points [-]

It's a moderately good hack, but it isn't of infinite versatility, barring the addition of a bit more cheating to get around the sleep/food problems.

I think we can let Harry sleep. For example


Instead of drawing a tally mark on his arm, Harry punches a hole in a ticket.

Original Harry doesn't set up chairs in seats 11-20. Instead, he puts a rolling hospital stretcher where chair 11 would go, and leaves 9 empty spots where chairs 12-20 would go. The rolling stretcher has pillows, an empty sleeping bag, and a slot into which you can place a ticket.

When Original Harry moves the trunk to the hallway, he finds 9 stretchers lined up against the wall. Every stretcher has a ticket, and the tickets have 12, 13, 14... 20 hole punches. The stretcher are heavy, like a person is sleeping inside the sleeping bag. Original Harry moves these 9 stretchers into the 9 empty spots he blocked out earlier.

Original Harry puts on his conductors hat and waits for passengers. One of the passengers is Tired Harry, whose ticket has 11 punches. Tired Harry places his ticket into the slot on empty stretcher, climbs into the empty sleeping bag, and goes to sleep. Now all 10 stretchers have ticketed Sleeping Harrys.

On arrival at 5:00, Conductor Harry adds a punch to the ticket of all 10 stretchers. He removes the 10 stretchers from the trunk, and lines the first 9 up against the wall. The last stretcher, with 21 holes punched in its ticket, Conductor Harry stashes in the Great Hall.

At 5:30ish, in the Great Hall, a newly Refreshed Harry wakes up. He gets out of his sleeping bag, picks up his ticket, and continues the day.


Comment author: Kindly 09 July 2013 03:26:22PM 3 points [-]

Whether this method works or not is up to the GM; the as-stated rule is that "information cannot go back more than six hours in time, using any combination of Time-Turners", which would allow this, but it's possible that anything which results in someone having more than 30 hours to a day is also bad. Granted, the hypothesis that 6 hours is the universe simulator's buffer size would suggest that this works.

It's a bit scary that if this scheme fails, there's no clean way for it to fail. In the very simplest case -- you go back in time 6 hours and then try to go back in time 1 more hour -- presumably the Time-Turner just doesn't work and nothing happens. Here, that outcome is not self-consistent: there's only one spin of the Time-Turner, and if it fails then there are no multiple Harry Potters so there is no reason for it to fail.

So if this scheme goes against the Time-Turner constraints, the only consistent outcome is that something unspecified happens to one of the first 6 Harry Potters to prevent them from getting back into the trunk. And summoning unspecified obstacles by the power of Time-Turner consistency seems like a really bad idea.

To fix this, we could have each Harry Potter toss a 100-sided die and leave the loop on a 1 being rolled; then run this algorithm several times. It's likely that spontaneous catastrophic failure has a probability much less than 1%, so the most likely consistent loop assuming this scheme doesn't work is one in which Harry rolls a 1 early on, which is very unlikely to happen assuming this scheme does work. So if several trials of this algorithm consistently keep ending after 1-6 repetitions, then it's almost certain that the universe doesn't like it.

Comment author: gjm 09 July 2013 02:55:59PM 4 points [-]

Somewhat-credible conjecture: It is not possible for one Time-Turner to transport another through time. So when conductor Harry, carrying his trunk supposedly full of passenger Harries (Harrys?), flips his Time-Turner ... something bad happens. Maybe the others get left behind somehow, or the Time-Turner just doesn't work, or the universe ends, or something. Consequence: at least in any consistent branch of the universe, Harry fails to get his army of copies.

Comment author: Kindly 09 July 2013 03:03:03PM 4 points [-]

Can't this be solved by having conductor Harry pass his Time-Turner to smelly Harry around 5:30 PM? Then none of the in-between Potters actually have Time-Turners.

Comment author: linkhyrule5 02 July 2013 02:50:19AM 15 points [-]

On a side note -

"But what I must actually tell you is that you will find the standard introductory text in the north-northwest stacks of the main Hogwarts library, filed under M."

First, I rather appreciate the comic relief, Eliezer.

... But second, what the heck are Memory Charms doing outside the--

Right. Hogwarts. Crazies. Nevermind.

Comment author: loserthree 02 July 2013 03:24:24AM 7 points [-]

... But second, what the heck are Memory Charms doing outside the--

Right. Hogwarts. Crazies. Nevermind.

Or Quirrell, who has declared his intention to visit the restricted section, is planning to plant the book for Harry's 'benefit.'

Comment author: MarkusRamikin 02 July 2013 09:39:48AM *  21 points [-]

Would you guys agree that Harry is being unfair to Minerva regarding his Time-Turner? "But you thought it was your role to shut me down and get in my way."

At the time she had it locked, she was right: he'd been irresponsible with it and needed to stop abusing his new toy every time a minor problem arose, and there's not a hint that even Harry disagreed with that. You can't refrain from such corrective actions on the remote possiblity that limiting your student's options will do harm. Not-limiting an irresponsible student's options in the relevant way can also lead to harm.

Comment author: Decius 02 July 2013 08:58:29PM 0 points [-]

I still don't believe it's been explained why Harry didn't transmutate a one-crystal wide ring through the lock into paper. Is that part of what he blames himself for not thinking of?

Comment author: drethelin 02 July 2013 10:51:55PM 3 points [-]

the lock isn't just physical, it's magical.

Comment author: fezziwig 02 July 2013 05:34:23PM 20 points [-]

Yes, and it's part of a pattern of behavior. HJPEV consistently finds (seeks out?) uncharitable explanations for other peoples' behavior, especially when he's under stress. It's probably the most 11-year-old-like thing about him.

Comment author: drethelin 02 July 2013 05:14:25PM 13 points [-]

I think this is actually Harry's fault: He should've requested his time turner be unlocked as soon as he could plausibly argue that REALLY IMPORTANT things were happening around and to him. When Mcgonnigall first locked it, he was doing more harm than good with it.

Comment author: palladias 02 July 2013 02:17:05AM 24 points [-]

I loved this:

That's not how responsibility works, Professor." Harry's voice was patient, like he was explaining things to a child who was certain not to understand. He wasn't looking at her anymore, just staring off at the wall to her right side. "When you do a fault analysis, there's no point in assigning fault to a part of the system you can't change afterward, it's like stepping off a cliff and blaming gravity. Gravity isn't going to change next time. There's no point in trying to allocate responsibility to people who aren't going to alter their actions. Once you look at it from that perspective, you realize that allocating blame never helps anything unless you blame yourself, because you're the only one whose actions you can change by putting blame there. That's why Dumbledore has his room full of broken wands. He understands that part, at least.

Does anyone else run into the problem of frequently giving this advice to yourself and finding it useful, but struggling to find a non-awful way to convey it to other people? I don't want to get them to self-flagellate, but to look for what leverage they have and not worry as much about what it totally outside of their control. Stoicism seems like the main way people hit on this idea of responsibility in my social circle.

Comment author: Eugine_Nier 03 July 2013 01:15:31AM 4 points [-]

I think this is related to Harry's problem, highlighted in the three armies arc, with considering other people as potential sources of ideas.

Comment author: buybuydandavis 02 July 2013 08:06:07AM 19 points [-]

I think Harry phrased it poorly, and if he meant it, he was absolutely wrong.

Allocating blame on yourself is a category error. We morally judge to separate the sheep from the goats, the wheat from the chaff - in short, to sort into piles of approach and avoid. You're stuck with you - where ever you go, there you are - so the point of the categorical judgment is simply inapplicable.

The sensible and very valuable part of what he is saying is to look to what you can do, and don't seek to console yourself with "that was his responsibility". Such interpersonal judgments are all about roles

because you're the only one whose actions you can change by putting blame there.

But you can change your actions more directly and more effectively by changing them. Putting blame on yourself is one of the better paths to depression, which is not an effective state. Blame others where appropriate and useful, but don't blame yourself, only search for actions to improve the situation, and choose them. You blame others because their actions are not yours to choose. Don't blame yourself, choose better.

Comment author: Ritalin 02 July 2013 07:17:41PM 1 point [-]

This is absolutely excellent. Do you mind if I quote this in fiction I'll write in the future?

Comment author: buybuydandavis 06 July 2013 06:36:36AM 1 point [-]

Please do. But if you remember, please let me know when you do, so I can take a look.

Comment author: Ritalin 02 July 2013 07:15:51PM 2 points [-]

I don't want to get them to self-flagellate, but to look for what leverage they have and not worry as much about what it totally outside of their control.

Someone please tell Shinji Ikari about this radical notion.

Comment author: loserthree 03 July 2013 02:33:54AM 0 points [-]

I don't want to get them to self-flagellate, but to look for what leverage they have and not worry as much about what it totally outside of their control.

Someone please tell Shinji Ikari about this radical notion.

Vg jnf arprffnel sbe gur Puvyqera gb or qlfshapgvbany. Gur yrff gurl jrer noyr gb pbaarpg jvgu bgure crbcyr gur zber gurl jrer qevira gb pbaarpg jvgu gurve Rinf. Hagvy gur raq, nyzbfg rirelguvat sbyybjrq gur Fpranevb.

Comment author: Ritalin 04 July 2013 07:04:12AM -2 points [-]

I'm talking about Rebuilt, especially 3.0. Kaworu is kind of like a kid Dumbledore; nice, mysterious, facetious, and completely sucks at consoling or giving advice.

Comment author: Ritalin 04 July 2013 06:09:38AM -1 points [-]

I'm sorry, are you from Gargantia or Ente Isla? I can't understand a word.

Comment author: sketerpot 04 July 2013 06:18:19AM *  3 points [-]

That post consisted of (fairly minor) Evangelion spoilers, encoded with rot13 for the benefit of people who haven't seen it yet.

(For completeness' sake: the language of Ente Isla is English with a bunch of letter substitution, and the language that Ledo speaks in Gargantia is a letter-substituted offshoot of German. They're similar to rot13, but much more pronounceable, since vowels map to vowels and consonants to consonants. More info here.)

Comment author: CronoDAS 02 July 2013 08:28:17PM 2 points [-]

Someone did, but not until the last episode of the TV series.

And Shinji's personal and emotional life was screwed up, but NERV did indeed manage to stop every invading alien Angel; the threat that did them in was of a far different nature.

Comment author: Alsadius 02 July 2013 05:27:36PM 7 points [-]

Does it feel wrong to anyone else that he's basically complaining to a woman old enough to be his grandmother about how immature she is? This despite the fact that she's proven herself repeatedly to be willing to listen to good advice, and has pulled his bacon out of the fire by quick-witted crisis management at least once?

Comment author: Decius 02 July 2013 09:07:37PM 1 point [-]

She's handled a couple of crises well, but she didn't gain very much respect for not scolding Harry for taking more money out of his vault than she thought he needed.

Comment author: linkhyrule5 02 July 2013 07:47:47PM 1 point [-]

Maturity and competence are not the same thing.

Comment author: Alsadius 03 July 2013 03:20:42AM 2 points [-]

Immaturity may not be precisely correct, but he's definitely not accusing her of incompetence. Irresponsibility, perhaps. He's not saying that she tried and failed, he's saying that she didn't try. He's saying that she's just blindly playing a role, instead of actually acting responsibly, and that it's so hard-wired into her that it's not even worth him trying to correct it. Hard-wired irresponsibility is close enough to immaturity that it's a reasonable approximation.

Comment author: Viliam_Bur 03 July 2013 10:54:52AM 4 points [-]

He seems bad at using people. And that is a weakness, compared with his opponent.

Comment author: drethelin 02 July 2013 07:59:28PM 7 points [-]

He's an angry 11 year old, and this isn't the first time he's yelled at her.

Comment author: Alsadius 03 July 2013 03:26:18AM 5 points [-]

Of course. This isn't surprising behaviour, but it is behaviour that makes me think less of Harry. (That said, it's one of his few traits that makes me actually think he's eleven, so perhaps I should be grateful)

Comment author: [deleted] 04 July 2013 06:03:42AM *  3 points [-]

Since no one here has mentioned it (as far as I see), note that Harry spends a significant portion of chapter 91 checking his watch every two minutes. Also note the sentence beginning,

From the outside you would've just seen . . .

Given the frequency and the aforementioned sentence, I think it's not likely that he's just counting down the time till dinner. He could be distracting himself, but he keeps it up during the conversation with his parents. Also, HPJEV is presumably familiar with such a common method of distracting oneself when thinking painful thoughts.

For the record, my current bet is that he used his time-turner and some transfiguration to do something with Hermione's body. The first thing that comes to mind is partial transfiguration of her brain into something much more durable. Taking her entire body is also an option if he can work up a passable fake.

Comment author: bogdanb 05 July 2013 10:53:42AM *  3 points [-]

Also, note that chapters 88 and 89 are titled "Time pressure", and the exact date and time is specified repeatedly throughout the text. In addition, there’s something funny in chapter 90: Right before Harry has the hypothermia idea, there's a discontinuity:

[The Headmaster] had vanished from where he was standing over the Weasley twins and come into existence beside Harry; George Weasley had discontinously teleported from where he was sitting to be kneeling next to his brother's side, and Fred was now lying straight with his eyes open and wincing as he breathed.

Right after Harry explains the Frigideiro, there’s this:

Fred and George started sobbing.

Which suggests a time loss (likely someone messing with Harry’s memory, the discontinuity sounds a bit like what Mr. Hat did). The sobbs might be because the twins knew what happened during that time, and realized that too long passed for the spell to do anything.

Harry also looks at the Time Turner when he gets it unlocked, and seems to notice or confirm something.

There’s a lot going on here we’re not told.

Comment author: Macaulay 04 July 2013 05:27:48AM 1 point [-]

What's "Harry James Potter-Evans-Verres" an anagram for?

Comment author: fubarobfusco 04 July 2013 05:48:38AM *  3 points [-]

Sarajevo server nymphs retreat.
Shaven tart Marjory perseveres.
Majesty's pervert overran rheas.
Jeremy's transverse vapor earth.
Trojan's preservers tame Harvey.
Jester's revery proves amaranth.
Jerry's pervert overate shamans.
Rajahs' poverty nerve streamers.
Majors preserve earthy servant.

... and a lot of other things.

Comment author: mare-of-night 04 July 2013 02:07:11AM 9 points [-]

I wonder if resurrection via transfiguration is possible? It's probably too simple a solution narrative-wise, but it seems like something a reductionist should at least try.

Harry and Hermione's failed attempt to transfigure a lost book is evidence against this working, since that also involved transfiguring something specific that contains information. But magic has enough strange rules that there are plausible reasons why that could fail but transfiguring a specific person could succeed - maybe you can't transfigure a specific thing while the original still exists, or something like that.

Harry would probably want to start with some less ethically risky experiments, to avoid making a doomed conscious that doesn't want to die. He could check whether transfiguring a copy of a brain works by having someone else train an animal to do something unusual, and then trying to transfigure an object into that animal. He'd know it worked if the trainer observed the animal doing the thing it was trained to do. (The person doing the transfiguration shouldn't know what knowledge the animal has that makes it unusual, so that they have to transfigure that specific animal, not just an animal with the same appearance that knows the same trick.) For good measure, he should try doing this after killing the original.

If that worked, he'd have to find someone extremely good at sustaining transfigurations to transfigure Hermione, since he wouldn't want her to keep re-dying each time the transfiguration wore off. For it to be a permanent solution, Hermione would have to learn how to transfigure herself like a troll, which could take a while.

Now that I think about it, it should at least be possible to transfigure an inanimate object into a non-specific muggle, if it's possible to transfigure an object into a non-specific animal. If anyone ever did that, it's a really, really good thing they kept it a secret. (No one sees a problem with killing a pig by turning it back into a desk, or burning a transfigured chicken inside a bubblehead charm, and muggles already have less-than-human legal status. Someone might transfigure very short-lived servants, or worse.)

Comment author: Velorien 03 July 2013 09:34:40PM *  14 points [-]

"Other people have done huge amounts for me!" Harry said. "My parents took me in when my parents died because they were good people, and to become a Dark Lord is to betray that!"

(...) "So you are held back by the thought of your parents' disapproval? Does that mean that if they died in an accident, there would be nothing left to stop you from -"

"No," Harry said. "Just no. It is their impulse to kindness which sheltered me. That impulse is not only in my parents. And that impulse is what would be betrayed."

Chapter 20. It would seem Harry dodged a truly enormous bullet there.

Comment author: Velorien 03 July 2013 07:39:34PM *  7 points [-]

To throw on the pile of random maybe-foreshadowing:

I can well foresee that I am fated to sit in the Headmaster's office and hear some hilarious tale about Professor Quirrell in which you and you alone play a starring role, after which there will be no choice but to fire him. I am already resigned to it, Mr. Potter.

-McGonagall, Chapter 17.

This did get me thinking, however. Firing Quirrell would presumably include removing his registration as "Defense Professor" from the Hogwarts wards. What did adding him to said wards do in the first place? The implication must be that the wards somehow distinguish students and staff from intruders, yet they have never actually prevented anyone from illegally entering Hogwarts, nor alerted anyone to such an intrusion.

Comment author: Velorien 03 July 2013 07:41:06PM *  8 points [-]

Relating to the foreshadowing part,

Harry nodded, his eyes very wide. Then, after a second, "What do I get if I can make it happen on the last day of the school year?"

Comment author: Coscott 03 July 2013 08:06:31PM 1 point [-]

This is very likely foreshadowing.

How close are we to the last day of the school year? The most recent date is April 16th. Does anyone know when Hogwarts ends in cannon?

Comment author: Velorien 03 July 2013 08:26:25PM 2 points [-]

According to the wiki, the end-of-term feast of Harry's first year took place on the 8th of June in canon.

Comment author: Coscott 03 July 2013 08:33:46PM 2 points [-]

Ok. Yeah, I think the last story arc will be about Quirrell and will take place in June, which makes me think this one ends without the world ending.

Comment author: Desrtopa 04 July 2013 05:08:40AM *  1 point [-]

I am less confident than I was before that the plot will resolve before the academic year is over.

I considered the possibility of some sort of timeskip in which Harry is engaged in intensive research, but weighing against that, I strongly doubt that Harry is going to bring back a twelve year old Hermione at a point when he himself has grown substantially older.

Comment author: linkhyrule5 04 July 2013 06:41:32AM 4 points [-]

Why?

Remember, his motivation isn't to live a life together with Hermione or something. His motivation is for Hermione to live out her life.

Comment author: Eugine_Nier 04 July 2013 06:11:26PM 0 points [-]

I'm not convinced this is the case. Or rather I suspect his main motivation is the former, with the latter being a rationalization.

Comment author: linkhyrule5 05 July 2013 09:28:02PM 1 point [-]

Um.

We've seen nothing but evidence that Harry really does care for Random Bystander #4231. His True Patronus wouldn't work if he didn't genuinely want immortality for everyone.

Even if Harry stops caring for Hermione on a personal level (... not likely), he's still going to get around to resurrecting her in the process of resurrecting everyone.

Comment author: Eugine_Nier 06 July 2013 06:39:40AM *  0 points [-]

Harry's reaction to her death suggests he'd be willing to use methods to bring her back that wouldn't work applying to everyone, e.g., some type of equivalent exchange. Heck, most of the more promising ideas for saving Hermione involve killing someone else.

Comment author: Desrtopa 04 July 2013 06:54:23AM 2 points [-]

I think it's more probable in narrative terms that there will be at least some respect in which Hermione can remain Harry's peer on restoration.

Comment author: cywtLC2Fy8A 03 July 2013 09:58:07AM 32 points [-]

Harry has already upgraded two existing spells: partial transfiguration and Patronus 2.0

In both cases, he achieved the impossible by ignoring what wizards believe and instead concentrating on his own beliefs.

What does Harry believe about Hermione that other wizards do not? He believes she is a purely biological machine, that there are no souls, and that a reductionist viewpoint is correct.

Therefore, in the right frame of mind, perhaps Harry can reparo a dead human (although canon!reparo cannot repair magical items properly, I wonder if it might restore Hermione without her magic, and if she might just be just as awesome without it.)

Comment author: mavant 03 July 2013 12:08:41PM 0 points [-]

So much win.

Comment author: Izeinwinter 03 July 2013 11:20:15AM *  2 points [-]

... This is perfect.

Comment author: Izeinwinter 04 July 2013 03:56:03AM 6 points [-]

ill go further. This could be the philosophers stone. It is not a physical object, it is a 600 year old scrap of parchment that explains this. Flamel routinely obliviates this idea from his head after repairing his body back to optimum operating condition because allowing any first year student to live forever and to /raise the dead/ is an insight that seems obviously catastropic to someone raised before modern agriculture and contraceptives.

Repairo works on anything still recognizably a certain kind of object? This would let you restore anyone who has any remains left at all..

Comment author: Desrtopa 04 July 2013 05:03:31AM 3 points [-]

This raises the question of how Flamel is so sure Voldemort couldn't replicate the Stone though. If he doesn't know what it is, he's in no position to make such a claim at all, and if that were what it was and he knew it, this should be just the sort of thing that anyone familiar with Voldemort should expect him to think of.

Comment author: Izeinwinter 04 July 2013 06:26:35AM *  2 points [-]

He is in fact not sure of this at all. The entire point of maintaining the illusion that there is a magical macguffin is to keep people like voldemort from speculating about how he maintains his youth. As long as the world is barking up the alchemy tree...

Comment author: shminux 03 July 2013 10:03:33PM 4 points [-]

Why the magical dualism? Since the magic ability has been confirmed genetic and not external in the earlier testing with Draco, a "repaired" wizard will remain a wizard.

Comment author: alex_zag_al 04 July 2013 01:04:47AM 10 points [-]

There's a genetic marker that the Source of Magic recognizes. The gene is still there, but the magic may not be. What wizards believe to be the soul leaving might be the Source of Magic withdrawing its power.

Comment author: shminux 04 July 2013 05:57:35AM 0 points [-]

What wizards believe to be the soul leaving might be the Source of Magic withdrawing its power.

Sure, that makes sense. But why would it not come back once the person is alive again?

Comment author: [deleted] 04 July 2013 02:11:30PM 1 point [-]

Because a stateless system is always simpler than a stateful one.

If it assigns magical ability to living brains with wizard genes, that is strictly lower Kolmogorov-complexityi than identifying a wizard at birth, tagging them and then withdrawing power when they 'die'.

(Stateless means no hidden variables; everything can be decided locally.)

Examples of powerful stateless systems: The basic logic gates, the Link Layer of the Internet (barring traffic control utilities), Lambda Calculus, and others.

Comment author: shminux 04 July 2013 04:06:26PM *  1 point [-]

You seem to confirm my point. It's a basic logic gate: (wizard genes & alive) = magical ability. remembering that the person was once dead is an extra complication.

Comment author: linkhyrule5 04 July 2013 04:47:17AM 6 points [-]

... It strikes me that Harry's wand could not be affected by a normal reparo, up until someone threw the Elder Wand itself at it...

Comment author: ikrase 04 July 2013 01:00:05AM 6 points [-]

According to Quirrel (this might not actually be accurate) troll regeneration works by constantly transmuting itself into its own body. I wonder if that can be applied to a human...

Comment author: chaosmage 05 July 2013 01:49:55PM 2 points [-]

But memories, like wounds, would be constantly overwritten. This troll, while quite competent in many ways, never displayed learning ability.

Somehow I don't think a human unable to learn would be what Harry would consider a valuable result.

Comment author: falenas108 15 September 2013 04:34:17AM -1 points [-]

This is if the spell made logical sense when carried out to the fullest. But, magic doesn't work like that, it works the way we would naively think if we said "transforming back into itself."

Comment author: Sheaman3773 24 August 2013 04:03:35AM 2 points [-]

First, I'm not sure how much learning precisely you were expecting from the troll in this limited period of time, most of which was taken up by it feeling fly-bites and smacking around the flies, nor even how you would expect for such to be seen.

Secondly, it did seem to learn. George hit it with three Ventus spells, each one moving it further towards the edge of the terrace. Between the second and the third, the troll dug its hand into the stone, anchoring it in place so that it would not be blown over the edge. If that's not adapting to match a new threat, I'm not sure what would be--certainly not in the brief time of the fight where most of the attacks were on the level of fly-bites.

If that is not displaying a learning ability, I would like to hear an example of a learning ability that it could have displayed.

Comment author: ikrase 05 July 2013 06:39:31PM 2 points [-]

I... think that the effects there would actually be much worse: The troll would be basically stateless. It's not even clear how that sort of thing would avoid disrupting the transfig. process.

Perhaps it's somewhat more advanced, like the charms that McGonagall was mentioning.

Comment author: NihilCredo 04 July 2013 03:25:28AM 2 points [-]

Harry would have to maintain the transfiguration for the rest of Hermione's life, or until they find a replacement solution. Given the extent of the injuries that may not be within his strength.

Comment author: sketerpot 04 July 2013 06:24:45AM 3 points [-]

It does sound like exactly the kind of clever hack Harry would use to get an indefinite healthy lifespan, though.

Comment author: ikrase 04 July 2013 03:52:28AM 1 point [-]

Hermione would probably maintain it. Or maybe someone else. Harry should probably be doing this to himself, too.

Comment author: FiftyTwo 04 July 2013 12:11:09AM 1 point [-]

Both of those cases depended on a crucial insight rather than knowledge (Dementors represent death rather than fear, the boundaries of objects are arbitrary) I'm not sure if knowledge of physicalism is analogous.

Comment author: NancyLebovitz 03 July 2013 01:51:10PM 4 points [-]

Ideas about what Hermione without magic would do? Presumably some sort of research with occasional overwhelming research-based action, but science? magic? some combination?

Comment author: DanielLC 04 July 2013 06:41:59AM 1 point [-]

Become a dentist?

Comment author: ikrase 04 July 2013 12:58:31AM 3 points [-]

Possibly she would get outfitted with a truly ridiculous array of magic items?

Comment author: EndlessStrategy 03 July 2013 09:01:49AM 2 points [-]

The most obvious reason for Quirrel's actions at the end of this chapter is to prevent the prophecy from coming true. The next most obvious, and what I think is correct, is that he's taking those precautions because he wants to make sure Harry doesn't die before he makes the prophecy come true.

Comment author: William_Quixote 03 July 2013 08:46:14PM 6 points [-]

Professor Quirrell spoke with eyes half-lidded, looking out like through slits. "More than the question of whom the prophecy spoke - who was meant to hear it? It is said that fates are spoken to those with the power to cause them or avert them.

http://hpmor.com/chapter/86

Quirrell is of the view that prophecies are sometimes of things that can be prevented.

Comment author: DanArmak 03 July 2013 06:30:42PM -1 points [-]

But a prophecy can't be prevented from coming true. Otherwise it would just be a prediction.

Comment author: gwern 03 July 2013 06:35:43PM 3 points [-]

But how it comes true is very flexible, and we are warned repeatedly against any simple naive notion like 'a prophecy will come true literally as you think it will', in http://hpmor.com/chapter/86 http://hpmor.com/chapter/28 http://hpmor.com/chapter/72 (especially chapter 86 - why would Merlin bother with a Hall if it was as futile as all that?).

Comment author: ikrase 04 July 2013 01:02:53AM 3 points [-]

It's worth noting that Harry's prophecy is partially imperative and partially conditional.

Comment author: CAE_Jones 03 July 2013 08:33:02AM 10 points [-]

An idea I read on the HPMoR subreddit that I don't remember finding here is that "the very stars in heaven" could refer to the Blacks (Every last one of them that we know of has star, constellation or galaxy-related names, including Draco). Hermione also offered "the skeleton is a key" as a hypothetical for what a prophecy that means "Susan Bones has to be there" might sound like, and Hermione did study prophecy on Harry's urging, and we know that Hermione retains book knowledge much better than Harry, though this is still rather weak evidence for a stars -> Blacks style riddle. It did seem pretty unlikely that Belatrix/Sirius would have a reasonable way to reenter the story in the time that remains, but that particular interpretation of the prophecy does point that way--and they are unclosed plot parentheses in the story's final stretch.

Side note: Narcissa was a Black by birth (Belatrix's sister, in fact), and "stars in heaven" is, as other readers have pointed out, an odd phrasing for what would normally be called "the heavens", but not particularly odd if heaven = happy afterlife or wireheading.

Comment author: monsterzero 06 July 2013 02:57:58AM 3 points [-]

The word "very" in this sense means "literal". The prophecy is talking about actual stars.

Comment author: malcolmocean 22 July 2013 11:48:29AM 4 points [-]

"very" is the original "literally". I.e. it used to mean "verily" or "in actual fact" and has gone through the same process that "literally" is going through now, where it's just intensive. "really" went through this process shortly after "very" did.

Comment author: ygert 03 July 2013 10:13:12AM 3 points [-]

Interesting idea. Unlikely though. PredictionBook link.

Comment author: CAE_Jones 04 July 2013 10:40:57AM 1 point [-]

Agreed, unless of course Quirrell realizes it is a possible interpretation, at which point he either throws members of the family or their corpses or the tapestry into an airship and manipulates Harry into shredding it. For added effect, he names said airship "The World", then feels much less terrified. (Until Harry applies the principals behind said magical airship to create a magical mech capable of destroying planets, of course!) The defense professor's relationship with puns, however, seems insufficient for him to attempt such a strategy. (Then again, he figured out an interpretation of Harry's ritual chant at the end of Self Actualization...)

Comment author: TuviaDulin 03 July 2013 06:07:18AM 2 points [-]

What I'm surprised Harry didn't think of was bringing her to a muggle hospital. A combination of muggle and wizard medicine should be able to overcome some plain old shock and blood loss, no?

Comment author: RolfAndreassen 03 July 2013 03:04:41PM 3 points [-]

Time. The sort of massive blood loss you get from having both legs traumatically amputated high on the thighs is deadly within minutes, at the absolute most. How does Harry get her to an ER in that time? Not to mention mobilising paramedics and whatnot from their rest state to the sort of instant correct action that would be needed. Modern medicine has its limits; the wounds described for Hermione seem to me to exceed them. Really, calling Dumbledore is much more inherent - he is an experienced combatant with access to isntant transport and no need to get things from a cabinet.

Comment author: bogdanb 05 July 2013 11:08:32AM *  2 points [-]

Well, yeah, but still, ERs can work pretty well, wizards can teleport, witches are more resistant to damage than normal humans, and some magic potions and charms could be added to the conventional medicine. And hey, sudden dual amputation is serious, but it's not completely out of the possible, even ten years ago, especially with tourniquets applied very soon, instant transportation, and magic bonuses.

I mean, where have you seen people die of blood loss and shock, with easy access to medical personel, and nobody trying anything?

Comment author: CAE_Jones 03 July 2013 06:22:49AM 8 points [-]

In canon, after several failed attempts at using magical treatments, Arthur Weasely tried stitches on his Nagini bite, but the venom dissolved them. It wouldn't be surprising if the troll's bite, either naturally or due to the mastermind's buffings, would have similar properties interfering with muggle treatments. Actually, now that I think about it, that's not a bad explanation for why Harry's first aid attempt didn't work. Canon Voldemort does not like making a kill strike that can be easily treated (Rowling even intended for Arthur's bite to be fatal, according to interviews, but changed it while writing, presumably because Harry's link to Voldemort meant this would have broken him more than because it meant he could call for help in a timely fashion, not to mention the effects on his relationships with the Weaseleys.).

Comment author: Atelos 03 July 2013 05:57:49AM 3 points [-]

It seems to me that Harry was a bit too quick to dismiss the Resurrection Stone option. Certainly if it functions according to his current conceptions of it it won't bring Hermione back in the sense he finds meaningful. However the experience of that soul/magic explosion at Hermione's death gives at least some evidence of a soul actually existing, even if still not enough to make it the most probable explanation for the stone's function, and there are other non-soul requiring ways that the stone could function such as looking back in time for the most recent functioning mind. Given the potential difficulty in finding it and the legend about how it's actually counterproductive its still probably not worth spending much effort pursuing it if you don't already know that pursuing it = convincing Riddle/Quirrelmort to go fetch it out from whatever defences he has it under or breaking them yourself, but he should still probably have put a bit more thought into it before rejecting it.

Comment author: CAE_Jones 03 July 2013 06:16:42AM 7 points [-]

The impression I got from canon is that it works exactly as HJPEV believes even in the Rowlingverse; there is some evidence against this (the resurrected marauders insisting that death doesn't hurt, LIMBO! Dumbledore's information might not be things Harry could have figured out on his own), but as I recall, one of the resurrected ones said "We're part of you, after all", and Dumbledore's "Well of course it's in your head! But why should that make it any less real?" Even if there is an afterlife in the Rowlingverse, it seems like she really did not intend for there to be any method of communicating with it.

Of course, HJPEV does not have access to a copy of Harry Potter and the Deathly Hallows, so you're right that he's privileging his hypothesis, and should at least do the obvious test--come up with information that Hermione would know that Harry couldn't figure out on his own, use the stone and ask the Hermione that appears about it.

Comment author: gjm 03 July 2013 09:00:03AM 6 points [-]

the obvious test

Made trickier by the fact that the information needs to be reliably checkable by Harry. And preferably not something he might already have known but mostly-forgotten.

He needs, in other words, a problem in class NP but not P. (Where P is "Potter" rather than "polynomial".)

Comment author: CAE_Jones 03 July 2013 09:28:01AM 6 points [-]

"The location and description of a specific item in your muggle bedroom" or "Chapter, author, title and quotation from a book that you read but I did not" and "details on your family that you haven't yet told me about" seem like places to start. (The bedroom/family ones require he didn't get any such information over the Christmas break, but from the sounds of it he didn't.)

Comment author: William_Quixote 03 July 2013 03:00:22AM 2 points [-]

Chapter 90 now ends with a note that says:

There are no Author's Notes for this chapter. I will quickly remark that this chapter (and further ones up to Ch. 96) were written in advance and did not change in response to any reader speculations.

I did not notice this note when I first looked at the chapter. Does anyone know if this went up with the first posting or was edited in later? If it was edited in later, maybe we should take the random speculations more seriously. If it went up with the first post, then the same point may hold, but with regards to 88-89.

Comment author: loserthree 03 July 2013 12:58:44PM 0 points [-]

So we know, for egotistical example, that he did not add "Dumbledore had looked down over the side of the terrace and made a gesture before returning" in response to my post that included risking transfiguration sickness on the list of things for which Harry could get in trouble.

Or, at least, we know that is what the author wishes us to believe. dun dun daaaaaaaah

Comment author: Benquo 03 July 2013 03:22:38AM 5 points [-]

Eliezer added it in response to reader speculations.

Comment author: gwern 03 July 2013 03:16:00AM 5 points [-]

I didn't notice it either. But Eliezer posted this comment on Reddit: http://www.reddit.com/r/HPMOR/comments/1hh5ph/ch90_salvaging_gender_bias_in_hpmor/cauafkt He may've felt the need to bring it to wider attention.

Comment author: loserthree 03 July 2013 01:01:28PM 2 points [-]

ye shall also know that any events occurring there were also of my own impulse and not a halfhearted sop to feminists

Why would we think that? We would think that if he unfridged Hermione.

That is pretty strong evidence that Hermione will be resurrected sooner, rather than later. So I guess the ending where Harry resurrects everyone ever maybe won't seem more likely when this arc is complete.

Unless this is the end.

Comment author: linkhyrule5 03 July 2013 08:43:42PM 10 points [-]

Alternatively, McGonagall will become a PC.

Comment author: GeraldMonroe 02 July 2013 11:22:58PM *  7 points [-]

Prediction : Harry has stolen a march on Quirrelmort. I predict that between the time Professor Mcgonagall unlocked his time turner and Quirrelmort entered the room, he already used the device to visit the library's restricted section.

At least, I hope so : I really want to learn how "spell creation" is done, per EY's interpretation. That will tell us a lot about what magic actually is and what can be done to achieve Real Ultimate Power.

Furthermore, this would be fully rational. Harry's analysis of what to do next should have already made it abundantly clear that he needs to obtain more information, and the restricted section obviously has stuff that might be helpful. And why start on a task now when you can start on it 6 hours ago?

Comment author: Coscott 02 July 2013 11:31:44PM 3 points [-]

There is an error in your analysis. There is no reason to start 6 hours ago, since the alternative is being able to go back 6 hours in the future. Either way, he has the same amount of time. If he finds out he needs to do something in the past, then he could go back. The only difference between researching first and going back first, is that if he researches first, he keeps the option of using the time turner to do something else. (e.g. Use 6 versions of him to do something in parallel at the same time).

When choosing between closing doors available to him and researching, the rationalist researches first.

Comment author: Velorien 02 July 2013 10:35:27PM *  15 points [-]

Just came across this in re-reading chapter 3:

The Killing Curse rebounded and struck the Dark Lord, leaving only the burnt hulk of his body and a scar upon your forehead.

Why a burnt hulk when the Killing Curse does no physical damage whatsoever?

It strikes me that the body doesn't match Voldemort's presumed cause of death, there are no witnesses of said death (since Harry's memory cuts out early), and burning a corpse is a classic way to render it unidentifiable.

Moving from considering evidence to speculation, it strikes me that the prophecy would make it incredibly easy for Voldemort to fake his own death - if he went to the Potters' house, killed the parents, placed a mysterious mark on Harry, and then disappeared, leaving a body behind, there is no way his enemies wouldn't take that as his death and the prophecy's fulfillment.

Comment author: DanielLC 04 July 2013 06:45:32AM 1 point [-]

If it's plausible for him to be burnt by a rebounding killing curse, then the evidence for a faked death is weak. If it's implausible, he'd have found a better method to fake his death.

Comment author: Ritalin 04 July 2013 07:11:02AM 3 points [-]

plausible outcome a rebounding killing curse

It does not happen, there are no antecedents, nobody knows what happens.

Comment author: Alsadius 03 July 2013 04:51:26AM 2 points [-]

Why would he fake his own death, though? He was winning.

Comment author: hairyfigment 04 July 2013 07:06:45PM 1 point [-]

Because Voldemort isn't real, and Tom was tired of the game anyway when he learned he should probably focus on Harry. (If he died, and was inconvenienced the way Dumbledore thinks, how did someone consistently sabotage the Defense Professor? Though that's weak evidence for a couple reasons.)

Dumbledore doesn't realize that Voldemort is a mask, otherwise he'd be spamming this news everywhere. Even without understanding it, he gave Harry a big hint by faking the scene with the burnt chicken. He hoped Harry would think it through and arrive at the same conclusion. But Albus doesn't want to say it explicitly because it would sound silly, and he already looks like a lunatic.

Comment author: Sheaman3773 24 August 2013 04:13:35AM 1 point [-]

...I've never so much as heard the implication that Voldemort was actively sabotaging the Defense position so much as he cursed it once, and it is the curse that is continuing to do its work. Such speculation doesn't appear to make sense to me now that I have heard it.

Linking the burnt chicken to the burnt husk of Voldemort's supposed body, however...is not something that I've considered, and it actually makes some sense, though I do not say that with a high degree of certainty. Though, why wouldn't he have spoken up by now?

Comment author: Randaly 03 July 2013 11:13:09AM 2 points [-]

He was winning.

Probably not. While Voldemort's terrorist group was doing increasingly well, Dumbledore's presence alone would be sufficient to prevent a complete victory, and the entire civil war was a distraction from Voldemort's likely main concern, the muggles.

Comment author: JTHM 03 July 2013 05:15:05AM 7 points [-]

To make Harry Potter a worshiped celebrity.

Comment author: JenniferRM 02 July 2013 05:31:11PM 6 points [-]

What's up with Quirrell's twitching lips in Chapter 90?

"That spell of cursed fire. I don't suppose it's a sacrificial ritual that even a child could use, if he dared?"

The Defense Professor's lips twitched.

And then moments later after being deflected from the spell (which, though not named, is probably Fiendfyre?)

"Pity," the boy said. "It would've been nice to see the look on the enemy's face the next time they tried using a troll."

The Defense Professor inclined his head, his lips twitching again.

At the time I read it I just assumed that Quirrell's plans to turn Harry dark were advancing by leaps and bounds and getting such decisive confirmation was causing him to be happy about what he had wrought. After thinking about it some more I'm now wondering if "THE ONE WHO WILL TEAR APART THE VERY STARS IN HEAVEN" is someone who should be playing with fiendfyre? Maybe Quirrell's twitches were a sign of fear or worry based on having private knowledge of the prophesy in Chapter 89, in which case a prophetically ironic strategy adjustment may be in the offing?

Comment author: DanArmak 03 July 2013 06:40:00PM 6 points [-]

I find it incredible that Quirrel would ever show his true emotional state on his face, unless he wanted to. Especially given this chapter's title.

Comment author: Qiaochu_Yuan 02 July 2013 07:19:03PM *  5 points [-]

McGonagall's lips twitch when she's stifling a smile (this is stated several times in the text). Perhaps the same is true of Quirrell? In the second case, canon!Quirrell is responsible for both trolls that occur in the first book and at least according to Harry Potter Wikia is supposed to have a talent for using trolls. In the first case... I think what happened when Voldemort killed Harry's parents involved a sacrificial ritual (Lily sacrificing her life for Harry), so Quirrell might have found that particular idea ironic. Or maybe he's just amused by the idea of Harry using sacrificial rituals because of previous events.

Comment author: gwern 02 July 2013 07:46:52PM 3 points [-]

Also Dumbledore:

"I recognize the name, Harry," said Dumbledore. The old wizard's lips twitched upward. "Although honesty compels me to say that dear Winston was never one for pangs of conscience, even after a dozen shots of Firewhiskey."

No old uses for Quirrel aside from this:

The Defense Professor's shoulders twitched in a slight shrug, the only movement they'd shown since the battle ended.

Comment author: Macaulay 02 July 2013 04:16:50PM 9 points [-]

Is there a page that lists all of the unresolved hints/clues in MoR? For example, Remembrall-like-a-sun, Bacon's diary, etc.

Comment author: Sherincall 02 July 2013 07:44:12PM 5 points [-]

This list has been compiled on reddit some time ago. It goes up to chapter 85. Some things have been resolved since then.

Comment author: Qiaochu_Yuan 03 July 2013 02:04:14AM *  3 points [-]

Great list. I definitely haven't seen the map errors worked out to my satisfaction. From Chapter 25:

"Still on the fritz," said George.

"Both, or -"

"Intermittent one fixed itself again. Other one's same as ever."

I think at least one of these errors is Tom Riddle, although I'm not sure whether it's the intermittent one or the other one because I'm not sure whether it's more likely to attach to Quirrell or Harry. I don't have any good second candidates.

Comment author: Intrism 03 July 2013 02:29:40AM *  16 points [-]

I decided to enumerate all the map errors I could think of.

Name errors: any error in which someone's name is persistently not what you'd expect.

  • Quirrell being named Defense Professor.
  • Anyone (probably Quirrell, maybe Harry) being named Tom Riddle.
  • Quirrell or Harry being named Heir of Slytherin.

Map errors: any error in which the map itself is drawn incorrectly, or in a way you wouldn't expect.

  • The Chamber of Secrets entrance being drawn on the map if/when Quirrell accesses it.
  • Quirrell being drawn inside a wall if/when Quirrell accesses the Chamber of Secrets.
  • If Quirrell can become a spirit, Quirrell being drawn inside a wall when he is in fact inside a wall.
  • Harry being drawn in strange and incorrect places when he's inside of his trunk.

Name persistence errors: any error in which someone changes names.

  • Harry changing names while using his "dark side."
  • Quirrell switching between Quirinus Quirrell and "Defense Professor," possibly when Quirrell "rests."
  • Quirrell being labeled Salazar Slytherin, particularly when he accesses wards.
  • Harry being labeled something more commonly associated with Professor Quirrell when he uses his Potterdar.

Multiple dot errors: any error in which one person is in multiple places.

  • If the Dark Lord can become disembodied (perhaps while Quirrell is "resting"), separate "Quirinus Quirrell" and "Defense Professor" dots in different locations.
  • Any student with a Time-Turner showing up twice on the map.
Comment author: loserthree 03 July 2013 12:51:31PM 4 points [-]

As someone suggested earlier, it's possible that Sirius Black is hiding out as the Weasley owl (the "measured and courteous hoot"). That would fit with Peter Pettigrew being the unfortunate in Azkaban chanting, "I'm not serious."

It's also possible that Pettigrew is hiding out somewhere, I suppose, but that doesn't seem smart.

This also raises the possibility that someone or multiple someones who weren't ever Marauders using small animagus forms to get around the castle, which could show up funny on the map.

Comment author: linkhyrule5 13 July 2013 12:57:00AM 4 points [-]

We now also potentially have

  • A hidden troll is marked "Defense Professor".
Comment author: DanArmak 03 July 2013 06:42:09PM 2 points [-]

Please note that Dumbledore has used the map, and has commanded it to "find Tom Riddle". Many of your suggestions would lead Dumbledore to discover something he hasn't.

Comment author: Intrism 03 July 2013 07:01:07PM 1 point [-]

This isn't so. Quirrell was off campus when Dumbledore used the map. The only suggestion that it eliminates, assuming that Quirrell wasn't using his Potterdar at the time, is the idea that Harry is persistently labeled Tom Riddle.

Comment author: Sherincall 03 July 2013 02:27:45AM 1 point [-]

I don't think Tom Riddle would show up on the map, as Dumbledore drew a circle around Quirrell and presented him to the Hogwarts Security System as "The Defense Professor". I'm guessing the map just taps into that system, so that is all they'll see. It could be the constant one, as all the others show up by name. but I'm not sure they'd make a fuss about that.

As for the intermittent, I'm guessing it's Harry when he wears the Cloak - It is explicitly said that it doesn't just turn you invisible like other cloaks, but hides you completely (except for the eye, apparently).

My other candidate for the intermittent one is Time Turned people, but since several students have Time Turners I'm guessing the twins would figure it out eventually. More likely, it just shows the 'current' version of the person.

...Actually, if that were the case, the map could be used to figure out which of the copies isn't time turned. Not sure what you'd do with that info, though.

Comment author: gjm 03 July 2013 09:08:37AM 1 point [-]

As for the intermittent, I'm guessing it's Harry when he wears the Cloak

If the Weasley twins noticed Harry appearing and disappearing, they wouldn't be calling that "[the] intermittent one", they'd be calling it "Harry" or "Potter" or something. No?

Comment author: Sherincall 03 July 2013 09:31:35AM 0 points [-]

True.

Also, I assume if they saw Tom Riddle or Salazar Slytherin or some other name they consider utterly evil, they'd tell Dumbledore immediately, rather than dismiss it as a bug. Even if they've never heard of Pascal's Mugging, that's just the sane thing to do.

Comment author: gjm 03 July 2013 11:14:48AM *  3 points [-]

I agree with robryk: they've probably never heard of Tom Riddle. And I fear that if they saw SS's name their reaction would as likely be "hey, cool!" as "OK, let's go and talk to the headmaster".

[EDITED to add: hi, downvoter(s). If you'd like to tell me what you think I did wrong, I can probably try to do it less in future.]

Comment author: fubarobfusco 03 July 2013 09:45:28PM -2 points [-]

Wouldn't Tom Riddle have been at school around the same time as the Weasley twins' grandparents?

Comment author: Velorien 03 July 2013 09:58:31PM 3 points [-]

But why would they know the names of people in the school at the same time as their grandparents?

Comment author: gjm 03 July 2013 10:21:13PM 3 points [-]

And, even if they did, they wouldn't know that Riddle = Voldemort. At least, in canon I think Dumbledore or someone says in so many words that scarcely anyone ever connected the two.

Comment author: robryk 03 July 2013 09:42:35AM 5 points [-]

Do they know who Tom Riddle is/was? I don't remember why they should and in canon it at least isn't common knowledge among students (Ginny didn't recognize the name of the person in the diary).

Comment author: Sherincall 03 July 2013 01:55:18PM *  5 points [-]

You are right. I'm updating in favor of "Tom Riddle" showing on the map. Still not convinced because when Dumbledore says "Show me Tom Riddle" the twins don't go "Hey, that's the guy that keeps popping up!". That might have happened off screen, but we don't see any evidence that it did.

EDIT: I have re-read that part, and Dumbledore waits until he is alone in the room to say "Find Tom Riddle".

On the other hand, I admire the poetry where having a taboo on the name and story of Voldemort ultimately dooms you, just because you didn't want to remember and talk about the bad things. Harry even talks about this in one of the early chapters, I believe.

Comment author: taelor 03 July 2013 08:28:08AM 7 points [-]

My other candidate for the intermittent one is Time Turned people, but since several students have Time Turners I'm guessing the twins would figure it out eventually. More likely, it just shows the 'current' version of the person.

Bear in mind that the official explanation is that Time Turners are used to treat "Spontaneous Duplication". If the map showed multiple copies of a Spontaneous Duplication-sufferer running around, that might be dismissed as a feature, not a bug.

Comment author: tondwalkar 04 July 2013 03:33:39AM *  1 point [-]

I think "Spontaneous Duplication" is made-up by Minerva or someone as an explaination to wave off anyone who might see mulitple Harrys running around due to the time turner.

Comment author: Intrism 03 July 2013 02:36:55AM 2 points [-]

I don't think Harry wears the cloak often enough for the Weasleys to notice it. Even then, a missing Harry could be caused by many things other than the Cloak - perhaps the Weasleys just missed him, for instance, or he could be out to lunch with Quirrell. They'd have to watch him as he put the Cloak on for it to be notable.

... Although, hmm... If memory serves, the interaction of Cloak and Map is discussed in canon. Does anyone remember how that worked?

Comment author: Qiaochu_Yuan 03 July 2013 03:01:38AM 4 points [-]

If memory serves, the interaction of Cloak and Map is discussed in canon. Does anyone remember how that worked?

Harry Potter Wikia says Lupin saw Harry, Ron, and Hermione under the cloak.

Comment author: atorm 03 July 2013 03:41:51PM 0 points [-]

That never made sense to me. Four students built an artifact more powerful than a Deathly Hallow through which Death Himself cannot sense his prey?

Comment author: kilobug 03 July 2013 04:18:15PM 0 points [-]

It may have something to do with the fact that the legitimate owner of the Hallow participated in making the map, but the whole map itself is very overpowered for a group of 4 students to create anyway. If it was possible to create such a map, why wouldn't the Hogwarts authority create it ? It's much more likely that the map was made by someone much more powerful, and only slightly altered by the marauders. Maybe they just added the fact that's usually blank and you've to swear you're up to not good to make it work ?

Comment author: Qiaochu_Yuan 03 July 2013 07:56:48PM 2 points [-]

That's probably why its origin was changed in HPMoR (where, as opposed to in canon, it was originally part of the Hogwarts security system and possibly made by Salazar Slytherin).