Harry Potter and the Methods of Rationality

A slow, analog alternative to the internet

Moderators: SecondTalon, Moderators General, Prelates

User avatar
Pluvialis
Posts: 14
Joined: Mon Oct 24, 2011 6:18 pm UTC
Location: UK
Contact:

Re: Harry Potter and the Methods of Rationality

Postby Pluvialis » Mon Feb 06, 2012 7:40 pm UTC

jobriath wrote:I like your recursive-plotting idea but don't understand it. What if someone were to figure it out? If Quirrell were to work it out he could sit in the opposite chair and make a true statement in the Headmaster's interest (0 level deception). He knows about the wibbler but can choose to speaky truly despite it, which strikes me as still 0-level deception; or he can choose to speak truly because of it, in which case he knows the wibbler will register level 1 plotting because Quirrell is banking on the wibbler causing his words to be misinterpreted.

What if Quirrell resolves to enact an odd-numbered-level deception if the wibbler shows an even number, and vice versa? My guess is that it displays the message "REDUCTIO AD LEFT-HANDED BANANAS" and melts.

I suspect I too will never, ever figure out what the wibbler does.


This is hilarious :P
Last edited by Pluvialis on Mon Feb 06, 2012 7:43 pm UTC, edited 1 time in total.

User avatar
Pluvialis
Posts: 14
Joined: Mon Oct 24, 2011 6:18 pm UTC
Location: UK
Contact:

Re: Harry Potter and the Methods of Rationality

Postby Pluvialis » Mon Feb 06, 2012 7:42 pm UTC

Yakk wrote:given a mortal being on the other side.


Be careful, sounds like you think rationality is tied to some transcendent quality and can be infinitely expanded! :P

User avatar
Argency
Posts: 203
Joined: Wed May 19, 2010 12:43 am UTC
Location: Brisbane, Australia

Re: Harry Potter and the Methods of Rationality

Postby Argency » Thu Feb 09, 2012 10:17 am UTC

Looking good for an update soon, given the new author's note at the start of Chapter 77. In the mean time, I re-read it and stumbled across at least one thing that I think is either a very minor Chekhov's Gun or a space that Eliezer has left in case he needs one at some point in the future. I'm going to read it all through again, I think, looking for more. Once you get a handle on what you're looking for then I reckon it shouldn't be too hard to find a few of them. For instance:

Spoiler:
At the end of Chapter 63 Sybill Trelawney,

"...came awake with a gasp of horror, a disruption of her breathing that left her feeling deprived of air and yet her lungs didn't move, she woke up with an unvoiced scream on her lips and no words, no words came forth, for she could not understand what she had seen, she could not understand what she had seen, it was too large for her to encompass and still taking shape, she could not put words to that formless shape and so she could not discharge it, could not discharge it and become innocent and unknowing once more.

"What time is it?" she whispered.

Her golden jeweled alarm clock, the beautiful and magical and expensive alarm clock that the Headmaster had given her as a gift upon her employment at Hogwarts, whispered back, "Around two in the morning. Go back to sleep.""


The clock. Dumbledore gave her a clock just after she came to Hogwarts (ie - just after she gave her first and only prophecy). It's a nice clock and a memento, so she'd never get rid of it, and it sits right beside her bed while she sleeps. I just think this smells suspiciously like the author making sure he mentioned it in a casual but specific way, like he wants it to be there but he doesn't want anyone to notice until he points it out later. So...

That thing has got to be recording everything that goes on in Trelawney's unconscious brain, just in case she ever prophecies when noone is around. MoR cannon says that seers don't ever remember their own prophecies, so Dumbles would need this sort of thing. I wonder if he has other safeguards around her so that he can jump on her and get her somewhere private in the event of a public prophecy like he does somewhere earlier when she starts up in the Great Hall... Importantly, Dumbledore may or may not have missed the prophecy that woke her up because she herself couldn't understand it and was therefore unable to form a prophecy. So we know from context that Harry's vow to find a way of revolutionising the human condition has set great events in motion (whether or not he succeeds) and we can infer from the clock that it's important to the story either that Dumbledore knows this via the clock or that Dumbledore cannot have known this despite the clock, since Sybill wasn't able to form a prophesy.


Anyways, maybe I'm digging too deep here and it's just a clock, but has anyone else noticed anything that looks like it was put there for later reference?
Gonna be a blank slate, gonna wear a white cape.

User avatar
Kisama
Posts: 137
Joined: Tue Jan 20, 2009 5:52 am UTC
Location: (0, 0, 0)

Re: Harry Potter and the Methods of Rationality

Postby Kisama » Thu Feb 09, 2012 11:46 am UTC

Argency wrote:Anyways, maybe I'm digging too deep here and it's just a clock, but has anyone else noticed anything that looks like it was put there for later reference?
I agree that the clock does seem to have some significance.

Off the top of my head, other potential Chekhov's Guns or similar:
  • Roger Bacon's diary (Slightly spoilerific link)
  • James Potter's rock
  • Maybe Fawkes counts, as in canon
  • Thinking along those lines, perhaps the flaming chicken..?
  • The apparently original Hogwarts crest Hermione identifies on the wall of Dumbledore's office
  • At this stage the Marauder's Map is still in the hands of the Weasley twins, and there is mention of two mysterious glitches, which are almost certainly going to be important

4d0m,jobriath & WarDaft wrote:[explanations of Quirrel's healer hypothetical]
Ah, thanks, it does make sense that way.
cd880b726e0a0dbd4237f10d15da46f4

User avatar
Argency
Posts: 203
Joined: Wed May 19, 2010 12:43 am UTC
Location: Brisbane, Australia

Re: Harry Potter and the Methods of Rationality

Postby Argency » Thu Feb 09, 2012 12:57 pm UTC

Kisama wrote:Off the top of my head, other potential Chekhov's Guns or similar:
  • Roger Bacon's diary (Slightly spoilerific link)
  • James Potter's rock
  • Maybe Fawkes counts, as in canon
  • Thinking along those lines, perhaps the flaming chicken..?
  • The apparently original Hogwarts crest Hermione identifies on the wall of Dumbledore's office
  • At this stage the Marauder's Map is still in the hands of the Weasley twins, and there is mention of two mysterious glitches, which are almost certainly going to be important


I'm glad I don't sound crazy to everyone about the clock then. I definitely agree that Roger Bacon's diary and James Potter's rock are giant smoking Chekhov's Guns (although I guess we were supposed to notice them), general consensus seems to be that
Spoiler:
the diary is suspiciously similar to Tom Riddle's diary from canon and the rock could be tied to the Philosopher's Stone. I personally wonder if Dumbledore is feinting with the rock and it's actually just a rock: seems like having a number of semi-obvious possible hiding spots for the Philosopher's Stone would be a good way to make anyone looking for it think that it was actually hidden somewhere, which would mean that any effort spent looking for it would be wasted if you had actually destroyed it years ago (would also work for making it look like that was what you were trying to achieve, etc, etc). Harry would probably rage long and hard about the Stone's destruction unless Dumbledore could demonstrate that the consequences of Voldemort getting his hands on it made it unusable for public consumption. I also think that Dumbledore has better evidence for Voldemort's continued survival than he's letting on, although I'm probably not unique in that last bit.

I agree that the malfunctions on the Map will probably be significant, although
Spoiler:
I'm assigning a high probability estimate to the possibility that Pettigrew and Voldemort are responsible for them
- again it's not a very secret C.G. since Eliezer would have known that everyone would have noticed it on first reading. Does it still count if the items/occurrences in question are obviously foregrounding something from the get-go, or does a Chekhov's Gun have to be the sort of thing you're not supposed to think about until it's brought to your attention? I guess there'd be a grey area anyway.

Anyway, I'd consider the crest suitably innocuous but I don't attach a high likelihood to it becoming a crucial plot item. I think we're on the right sort of track here though. This is fun! Can anyone see anything else? Then again, I'm going to feel like I accidentally found out what I was getting for Christmas if anyone actually tells me how they think it's all going to end and I agree with them...
Gonna be a blank slate, gonna wear a white cape.

User avatar
Kisama
Posts: 137
Joined: Tue Jan 20, 2009 5:52 am UTC
Location: (0, 0, 0)

Re: Harry Potter and the Methods of Rationality

Postby Kisama » Thu Feb 09, 2012 1:33 pm UTC

Argency wrote:I agree that the malfunctions on the Map will probably be significant, although
Spoiler:
I'm assigning a high probability estimate to the possibility that Pettigrew and Voldemort are responsible for them
Hmm, perhaps, but
Spoiler:
given the infamous story of the Weasley's rat in HPMoR, I would think they'd have properly investigated if they saw "Peter Pettigrew" on the map. Likewise they'd probably turn the map over to Dumbledore if they saw "Voldemort", but wouldn't take any notice of "Tom Riddle" since the History of Magic syllabus seems to be exclusively about irrelevant battles rather than including potentially useful information like Voldemort's real name. I'm thinking the glitches would have to be something clearly wrong with the map's normal functionality rather than just a suspicious name, but I could still be wrong. One glitch is intermittent and the other permanent... I just remembered that when I read that, I thought that perhaps one of the glitches was that it shows duplicate people, which would be caused by time-turning.
Argency wrote: - again it's not a very secret C.G. since Eliezer would have known that everyone would have noticed it on first reading. Does it still count if the items/occurrences in question are obviously foregrounding something from the get-go, or does a Chekhov's Gun have to be the sort of thing you're not supposed to think about until it's brought to your attention? I guess there'd be a grey area anyway.

According to tvtropes, "an unimportant element introduced early in the story becomes significant later on", so I guess things that are obviously meant to be significant don't really count, but that's why I said "or similar" ;) Of course, there is some degree of YMMV, for example when I watched "28 Weeks Later"
Spoiler:
I thought it was rather blatant that heterochromia iridum would turn out to be linked to immunity to the zombie infection. What a rubbish movie. Anyway.
Argency wrote:Anyway, I'd consider the crest suitably innocuous but I don't attach a high likelihood to it becoming a crucial plot item. I think we're on the right sort of track here though. This is fun!
Indeed :D
cd880b726e0a0dbd4237f10d15da46f4

User avatar
Vaniver
Posts: 9422
Joined: Fri Oct 13, 2006 2:12 am UTC

Re: Harry Potter and the Methods of Rationality

Postby Vaniver » Fri Feb 10, 2012 1:18 am UTC

The rock is almost definitely
Spoiler:
just a rock, given so that Harry will train his Transfiguration. It was no coincidence that McGonagall was the first person he saw after being given it.
I mostly post over at LessWrong now.

Avatar from My Little Pony: Friendship is Magic, owned by Hasbro.

User avatar
walkerm930
Posts: 69
Joined: Wed Apr 07, 2010 3:53 am UTC
Location: Canada: Ontario: Toronto

Re: Harry Potter and the Methods of Rationality

Postby walkerm930 » Fri Feb 10, 2012 1:46 am UTC

About Trelawney, there is a bit of a problem with that reasoning. It was explained that the pressure in Time is released when and where it needs to be, so it wouldn't make sense to put a monitor on prof. Trelawney. (of course if it is a monitoring device, she now could have the prophecy in her bed) Dumbledore of all wizards and his story-like view of the would would want it to happen naturally and unexpectedly anyways.

Though I would like to know what that scene was about...
In the gospel according to trig there are 3 primary rules: sin θ = x/h , cos θ = y/h and tan θ = x/y. These rules are not open to interpretation and are to be treated as law.

AlexRose
Posts: 38
Joined: Mon Sep 14, 2009 2:37 am UTC

Re: Harry Potter and the Methods of Rationality

Postby AlexRose » Fri Feb 10, 2012 3:39 am UTC

It occurred to me that Harry hasn't actually asked anyone if they feel a sense of doom around Quirrell. Tssk tssk, Harry. And you were so smug when you taught Hermione that lesson.

User avatar
walkerm930
Posts: 69
Joined: Wed Apr 07, 2010 3:53 am UTC
Location: Canada: Ontario: Toronto

Re: Harry Potter and the Methods of Rationality

Postby walkerm930 » Fri Feb 10, 2012 5:46 am UTC

About the above...
Spoiler:
In the warehouse after the prison break, Quirrel says that is is Harry's doom that flares, not his. However, Harry doesn't seem to believe this and marks it as a possible lie.

But he doesn't really have and excuse anyways, besides that no one else acts in an obvious way that would indicate similar feelings.
In the gospel according to trig there are 3 primary rules: sin θ = x/h , cos θ = y/h and tan θ = x/y. These rules are not open to interpretation and are to be treated as law.

User avatar
Kisama
Posts: 137
Joined: Tue Jan 20, 2009 5:52 am UTC
Location: (0, 0, 0)

Re: Harry Potter and the Methods of Rationality

Postby Kisama » Fri Feb 10, 2012 10:56 am UTC

AlexRose wrote:It occurred to me that Harry hasn't actually asked anyone if they feel a sense of doom around Quirrell. Tssk tssk, Harry. And you were so smug when you taught Hermione that lesson.
walkerm930 wrote:About the above...
Spoiler:
In the warehouse after the prison break, Quirrel says that is is Harry's doom that flares, not his. However, Harry doesn't seem to believe this and marks it as a possible lie.

But he doesn't really have and excuse anyways, besides that no one else acts in an obvious way that would indicate similar feelings.

There has been theorizing that Harry has been confunded, because the author has boldly stated that no-one would end up holding the idiot ball and it does seem that Harry is failing to do his due rational diligence. After all his musings on genre-awareness you'd expect he'd at least think twice about such an ominous phenomenon.

walkerm930 wrote:About Trelawney, there is a bit of a problem with that reasoning. It was explained that the pressure in Time is released when and where it needs to be, so it wouldn't make sense to put a monitor on prof. Trelawney. (of course if it is a monitoring device, she now could have the prophecy in her bed) Dumbledore of all wizards and his story-like view of the would would want it to happen naturally and unexpectedly anyways.

Though I would like to know what that scene was about...
My thoughts:
  • I think we can put a high probability that she was experiencing a prophetic episode, based on the fact that it's Trelawney, and the description of needing to discharge what she had seen.
  • I haven't managed to find that description of how prophecies work (it must have come after Chapter 72 which is all I have in PDF format) - I can't remember if Harry expressed any doubt, but how would anyone actually know whether prophecies were being made when no-one was around to hear them? I can't think of any reason that a prophecy would need to be released anywhere or to anyone in particular. However I think elsewhere it is stated or hinted that
    Spoiler:
    Snape was the true target of Trelawney's prophecy, not Dumbledore or McGonagall,
    and that only the intended listener will be able to hear all the nuances in the prophecy, so maybe that's right.
  • I don't think Dumbledore is quite willing to leave everything up to the laws of fantasy fiction, otherwise why put any effort into fighting Voldemort and rearing heroes when he can already assume that the good guys win in the end? He may not be savvy enough to owl grenades to death eaters, but maybe he could come up with a prophecy-recording device and other ways to give his side small advantages.
  • In canon: Based on the hall of prophecies in the Dept. of Mysteries I actually always assumed that wizards had some way to record prophecies. If the ministry is capable of monitoring the entire country for taboo words and underage magic, then why not also be able to monitor for prophecies, and make them trigger a recording spell?
cd880b726e0a0dbd4237f10d15da46f4

User avatar
WarDaft
Posts: 1583
Joined: Thu Jul 30, 2009 3:16 pm UTC

Re: Harry Potter and the Methods of Rationality

Postby WarDaft » Fri Feb 10, 2012 4:34 pm UTC

Re Harry and his sense of Doom around Quirrell...

Very early on, in fact almost immediately after he notices it and is a position to do something about it. He tries to tell Minerva about it. She tells him, in no uncertain terms, to shut up and never speak of it again.

Spoiler:
Harry started to get up from his chair, then halted. “Um, sorry, I
did have something else I wanted to tell you—”
You could hardly see the flinch. “What is it, Mr. Potter?”
“It’s about Professor Quirrell—”
“I’m sure, Mr. Potter, that it is nothing of importance.” Professor
McGonagall spoke the words in a great rush. “Surely you heard the
Headmaster tell the students that you were not to bother us with any
unimportant complaints about the Defense Professor?”
Harry was rather confused. “But this could be important, yesterday
I got this sudden sense of doom when—”
“Mr. Potter! I have a sense of doom as well! And my sense of doom
is suggesting that you must not finish that sentence!”
Harry’s mouth gaped open. Professor McGonagall had succeeded;
Harry was speechless.
“Mr. Potter,” said Professor McGonagall, “if you have discovered
anything that seems interesting about Professor Quirrell, please feel free
not to share it with me or anyone else. Now I think you’ve taken up
enough of my valuable time—”


In chapter 17. Incidentally, I just noticed another C.G. just mere paragraphs before that.
It was never covered what was so important that Harry had forgotten as evidenced while retrieving the Rememberall, was it?

Hmm... I don't remember this being in chapter 6 before:
like the "Dementor Exposure Treatment", which looked and smelled like ordinary chocolate.
All Shadow priest spells that deal Fire damage now appear green.
Big freaky cereal boxes of death.

User avatar
aldonius
Posts: 105
Joined: Sun Jan 17, 2010 2:33 am UTC

Re: Harry Potter and the Methods of Rationality

Postby aldonius » Sun Feb 12, 2012 8:49 am UTC

WarDaft wrote:Hmm... I don't remember this being in chapter 6 before:
like the "Dementor Exposure Treatment", which looked and smelled like ordinary chocolate.


IIRC it's been there for quite some time, probably since at least this time last year. But then again, memory is awfully fallible.

User avatar
Argency
Posts: 203
Joined: Wed May 19, 2010 12:43 am UTC
Location: Brisbane, Australia

Re: Harry Potter and the Methods of Rationality

Postby Argency » Sun Feb 12, 2012 11:08 am UTC

walkerm930 wrote:About Trelawney, there is a bit of a problem with that reasoning. It was explained that the pressure in Time is released when and where it needs to be, so it wouldn't make sense to put a monitor on prof. Trelawney. (of course if it is a monitoring device, she now could have the prophecy in her bed) Dumbledore of all wizards and his story-like view of the would would want it to happen naturally and unexpectedly anyways.


Oh hey you're absolutely right, the only way she could prophesise in her sleep is if the monitoring device was already there. I guess maybe Dumbledore wants to increase the likelihood that prophesies for him happen when noone else is around, so having the listening device there at night gives her 8 extra hours a day during which only Dumbledore is listening. Then again, maybe the author didn't consider that line of reasoning at all, or maybe it's just a clock. :)
Gonna be a blank slate, gonna wear a white cape.

User avatar
Loadstone
Posts: 21
Joined: Wed Aug 24, 2011 5:21 pm UTC
Location: TX, USA

Re: Harry Potter and the Methods of Rationality

Postby Loadstone » Wed Feb 15, 2012 5:18 pm UTC

I found an unexpected case of continuity in my last read through, and a possible time travel exploit based on it.

Spoiler:
Recall that during the attempt to factor large numbers using the Time Turner, Harry receives the message "DO NOT MESS WITH TIME". Also, recall that following the rescue from Azkaban, it is emphasized that not only is a Time Turner restricted to 6 hours use per day, but that not even information from more than 6 hours in the future can be known.

It seems that one possible explanation for the Time Warning is that Harry understood the algorithm too well. By this, I mean that Harry knows that if he sees a paper with the numbers 103*105, he KNOWS that time loops 101*(101 through 999) failed, and 103*(101 through 103) failed. This knowledge would require much more than 6 hours to accumulate through the algorithm.

The 2 numbers that Harry passes back can be replaced by n1 and n2. The algorithm described uses (2n1 + 101) * (2n2 + 101), where n1, n2: [0, 449], and Harry uses initial conditions n1 = n2 = 0, and increments n2 until it reaches 449, then increments n1 and resets n2 to 0. As I said above, Harry knows that if n1 != 0 or n2 > 5, at least 6 iterations failed, which provides future knowledge which can't be known.

The exploit would involve generating a list in which:
[*] rotates through all values 0 through 449 without repeating any values, where each value points to exactly one other value
[*] does the above in a way which Harry doesn't know, so Harry can receive any set of numbers and have no knowledge of previous iterations
[*] has a single number marked (explained below)
[*] an example of such a list would be xi = xi-1 + 7 (mod 450) since 7 and 450 are relatively prime

Harry would then use the following algorithm: if the paper is blank, pick any two numbers in [0, 449] and write them down. If the paper is not blank, convert the 2 numbers (2n + 101) and multiply them. If they equal the number, write the same values down. If they do not equal the number, consult the list and look ONLY at the number with value n2. Write down the value pointed to by that number as the new n2. If the value is marked, find the number with value n1 and write the value pointed to by that number as the new n1, else write down the current n1.

Such a scheme would guarantee all possible combinations are checked, but so long as Harry doesn't know how the list is constructed, he won't have information from more than 6 hours in the future. One concern would be that if n1 doesn't match what Harry would've picked (since he'd always pick the same numbers in a given situation), Harry might suspect that several iterations have passed, enough to loop n1. But Harry can't be sure that the previous value of n2 caused n1 to change, so he actually doesn't have any future information.


What do you think? I hope I explained it clearly enough (I probably went way overboard on the explanation in my attempt to be thorough).
"The only people who think children are carefree are the ones who've forgotten their own childhood." - OSC (who else?)

HonoreDB
Posts: 161
Joined: Tue Feb 06, 2007 4:32 pm UTC
Contact:

Re: Harry Potter and the Methods of Rationality

Postby HonoreDB » Wed Feb 15, 2012 6:13 pm UTC

That's pretty clever. I think the heart of it is the idea that the final loop should seem like it could be the first loop, even though it's improbable.

Of course, the whole idea of using an algorithm seems kind of cargo-cultish, since the Time-Turner is said not to operate by creating a series of timelines until a stable one is found. There's no reason we know of that the system "If there's no piece of paper, go back in time and leave a blank one. Otherwise, look at the piece of paper. If it has the correct factors, copy them and complete the time-loop. Otherwise, don't go back in time at all." wouldn't work equally well--either way, Harry's just blackmailing Time with the threat of a paradox.

User avatar
Loadstone
Posts: 21
Joined: Wed Aug 24, 2011 5:21 pm UTC
Location: TX, USA

Re: Harry Potter and the Methods of Rationality

Postby Loadstone » Thu Feb 16, 2012 12:22 am UTC

I don't follow you. If Harry intends to use the time turner to find the factors of a number, he'll need a method to propagate through the stages of the discovery. "Each" Harry must contribute to the solution until the "last" Harry receives the answer, despite the fact that for the sake of narrative interest we only follow the result of the "last" Harry. If any given Harry-instance doesn't contribute to the solution, then none of them will and the result is boring. The idea is to initiate (continue) recursion, rather than simply calling a function and hoping it gives a meaningful result.
"The only people who think children are carefree are the ones who've forgotten their own childhood." - OSC (who else?)

User avatar
phlip
Restorer of Worlds
Posts: 7573
Joined: Sat Sep 23, 2006 3:56 am UTC
Location: Australia
Contact:

Re: Harry Potter and the Methods of Rationality

Postby phlip » Thu Feb 16, 2012 12:36 am UTC

But there isn't an "each" Harry, and there isn't a propogation. Propogation implies that time passes, which doesn't make sense when you're talking about a specific point in time. You're saying there's, say, a 2 o'clock on Wednesday before you time-travel, and then a 2 o'clock on Wednesday after you time-travel... but that doesn't make sense, they're both 2 o'clock on Wednesday, they're not before or after each other. The whole idea presupposes a second, more "real" time axis, which people move along at a steady rate even while time-travelling.
It's a narrative convention that makes stories flow easier for authors and readers who are used to time existing, and acting in the normal way, so it's just a trope that makes the stories work better as stories. It doesn't make a whole lot of physical sense, and doesn't really have a place in a story like MoR which tries to make sense even if it means the readers have to think about it, rather than the usual "do what the readers expect even if it doesn't make sense when examined critically" pattern. Like humanoid aliens that speak English, and alternate-history fantasy that still happens to have modern social constructs, and the like... it's something you need a bit of, in order to ground your story for the readers, but if your world is entirely made of those, then it just gets bland, and far from the thought-provoking world that MoR tries to be.

In a self-consistent single-timeline time travel model, there's just one Harry, who makes a plan, finds a piece of paper which happens to have the right answer, writes that answer on another piece of paper, then goes back in time and plants it as the first piece of paper. The plan (of writing something different if the answer is wrong) is an attempt to make sure that getting the right answer is the only self-consistent result. As it happened, getting a piece of paper that just read "Don't mess with time" is also a self-consistent result.

Code: Select all

enum ಠ_ಠ {°□°╰=1, °Д°╰, ಠ益ಠ╰};
void ┻━┻︵​╰(ಠ_ಠ ⚠) {exit((int)⚠);}
[he/him/his]

User avatar
Loadstone
Posts: 21
Joined: Wed Aug 24, 2011 5:21 pm UTC
Location: TX, USA

Re: Harry Potter and the Methods of Rationality

Postby Loadstone » Thu Feb 16, 2012 1:13 am UTC

When I used the terms "each Harry" and "last Harry", I wasn't referring to different people; I was attempting to give meaning to every possible machine-state and its resulting action (hence the quotes). By "propagation" I intended the conceptual idea that each state must move toward the solution. I suppose my wording didn't exaggerate this sufficiently, largely because it is easier to conceptualize if one imagines multiple Harrys. My argument was meant to emphasize the necessity for a plan of action in any given situation - one which requires that the correct answer is the only stable timeline.
"The only people who think children are carefree are the ones who've forgotten their own childhood." - OSC (who else?)

User avatar
phlip
Restorer of Worlds
Posts: 7573
Joined: Sat Sep 23, 2006 3:56 am UTC
Location: Australia
Contact:

Re: Harry Potter and the Methods of Rationality

Postby phlip » Thu Feb 16, 2012 1:50 am UTC

Yeah, but the plan "If I get no paper, send back paper; if I get paper with wrong answer, send back no paper; if I get paper with right answer, send back a copy" still requires that receiving the right answer is the only stable timeline, but isn't an "algorithm" in which "each Harry" make changes which "propogate" towards some final answer. The final answer simply comes out of nowhere.

Code: Select all

enum ಠ_ಠ {°□°╰=1, °Д°╰, ಠ益ಠ╰};
void ┻━┻︵​╰(ಠ_ಠ ⚠) {exit((int)⚠);}
[he/him/his]

User avatar
WarDaft
Posts: 1583
Joined: Thu Jul 30, 2009 3:16 pm UTC

Re: Harry Potter and the Methods of Rationality

Postby WarDaft » Thu Feb 16, 2012 4:22 am UTC

It seems like at least some people have a decent grasp on Time Turners however. Snape for example, wants to know about the location of bullies, but not whether or not Hermoione was there, or he could not make her be there. This implies that you cannot use information that you get from time travel to ensure that that informatiom is correct. You must get some other information, and use it to ensure the results you wanted occur.


So you must have A(x) and B(x) which are independent, and C(x) such that C(x) => B(x), and then ask for x such that A(x), and then ensure C(x), to get A(x) ∧ B(x). I can't think of a suitable A,B,C to factor a number at the moment. There might not be, because there's no operation equivalent to "ensure C(x)" in math.
All Shadow priest spells that deal Fire damage now appear green.
Big freaky cereal boxes of death.

User avatar
Yakk
Poster with most posts but no title.
Posts: 11129
Joined: Sat Jan 27, 2007 7:27 pm UTC
Location: E pur si muove

Re: Harry Potter and the Methods of Rationality

Postby Yakk » Thu Feb 16, 2012 4:50 am UTC

That could easily be classic anthropoc error. Well the temporal paradox logic variety...
One of the painful things about our time is that those who feel certainty are stupid, and those with any imagination and understanding are filled with doubt and indecision - BR

Last edited by JHVH on Fri Oct 23, 4004 BCE 6:17 pm, edited 6 times in total.

User avatar
phlip
Restorer of Worlds
Posts: 7573
Joined: Sat Sep 23, 2006 3:56 am UTC
Location: Australia
Contact:

Re: Harry Potter and the Methods of Rationality

Postby phlip » Thu Feb 16, 2012 5:23 am UTC

Well, the rules of time travel are already pretty anthropocentric... consider the "if you know information from the future, you can't go back more than 6 hours from the source of that information" rule. In particular, the definition of "information" and "knows" that it takes for this exchange in Ch61 to make sense:
There was another pause, and then Madam Bones's voice said, "I have information which I learned four hours into the future, Albus. Do you still want it?"

Albus paused -

(weighing, Minerva knew, the possibility that he might want to go back more than two hours from this instant; for you couldn't send information further back in time than six hours, not through any chain of Time-Turners)

- and finally said, "Yes, please."
... are very anthropocentric. Specifically, that the knowledge that something is going to happen in about 4 hours that will provide information that would be relevant to him now... doesn't count as "information" for the purposes of the rule (otherwise there'd be no point in him doing the mentioned weighing of possibilities... he'd already be prevented from going back more than 2 hours just by Bones asking the question). Despite counting as "knowledge" in a mathematical sense.

Code: Select all

enum ಠ_ಠ {°□°╰=1, °Д°╰, ಠ益ಠ╰};
void ┻━┻︵​╰(ಠ_ಠ ⚠) {exit((int)⚠);}
[he/him/his]

User avatar
Kisama
Posts: 137
Joined: Tue Jan 20, 2009 5:52 am UTC
Location: (0, 0, 0)

Re: Harry Potter and the Methods of Rationality

Postby Kisama » Thu Feb 16, 2012 6:07 am UTC

WarDaft wrote:It seems like at least some people have a decent grasp on Time Turners however. Snape for example, wants to know about the location of bullies, but not whether or not Hermione was there, or he could not make her be there. This implies that you cannot use information that you get from time travel to ensure that that information is correct. You must get some other information, and use it to ensure the results you wanted occur.

So you must have A(x) and B(x) which are independent, and C(x) such that C(x) => B(x), and then ask for x such that A(x), and then ensure C(x), to get A(x) ∧ B(x). I can't think of a suitable A,B,C to factor a number at the moment. There might not be, because there's no operation equivalent to "ensure C(x)" in math.

I easily might have missed something, but I thought Snape knew where the bullies would be because he was eavesdropping, reading minds, or even instructing them. On the other hand Millicent knew where they would be because of her sister's time turner, she knew who would be there (shown, for example, by her glance at the Hufflepuff table the time Susan was Tonks) and she was using that information directly to get them to go there.
cd880b726e0a0dbd4237f10d15da46f4

AlexRose
Posts: 38
Joined: Mon Sep 14, 2009 2:37 am UTC

Re: Harry Potter and the Methods of Rationality

Postby AlexRose » Thu Feb 16, 2012 7:15 am UTC

Alright, I note my confusion. If I view someone traveling to my time from six hours in the future, I know their location six hours into the future. According to the 6 hour rule, does that imply there is no possible stable time loop in which I travel back in time before that point? Does it only apply to conscious, anthropocentric acknowledgement of information, or does it apply to any possible transfer of information, regardless if people are/can be aware of the significance? Is the six hour limit based on the relative time of a person (i.e have two time turners, use one to go back 6 hours, then use the other 6 hours later to go back in time again) the "absolute" timeline, or both? Speaking of "absolute" timelines, how does relativity play into all this?

User avatar
Kisama
Posts: 137
Joined: Tue Jan 20, 2009 5:52 am UTC
Location: (0, 0, 0)

Re: Harry Potter and the Methods of Rationality

Postby Kisama » Thu Feb 16, 2012 9:15 am UTC

AlexRose wrote:Is the six hour limit based on the relative time of a person (i.e have two time turners, use one to go back 6 hours, then use the other 6 hours later to go back in time again) the "absolute" timeline, or both?
Harry asks Dumbledore a similar question:
"Sorry to ask but I was wondering, is it possible to get more than six hours if you use more than one Time-Turner? Because it’s pretty impressive if you’re doing all that on just thirty hours a day.”
“I’m afraid Time doesn’t like being stretched out too much,” said Dumbledore after the slight pause, “and yet we ourselves seem to be a little too large for it, and so it’s a constant struggle to fit our lives into Time.”
Which doesn't explicitly rule out getting more than 6 hours, but does seem to imply it. Oh, I wonder how a day is defined for the purposes of time-turning? Can you use only 6 hours between midnight of one day and the next, or is there a rolling 24-hour window? I suppose it would have to be the latter, because the actual time of day is completely arbitrary and we have time zones and then how would a time-turner work on the moon? I think this is also somewhat related to your question about relativity, and I guess that all time calculations would be relative to the Source Of Magic's frame of reference, so if you spin your time turner while traveling at a speed approaching c and your personal time is slower, you will go back x hours relative to the source of magic, which will therefore be < x hours relative to yourself... I think? I know far too little about quantum mechanics to even make educated guesses here.
cd880b726e0a0dbd4237f10d15da46f4

User avatar
jobriath
Posts: 256
Joined: Wed Apr 04, 2007 2:11 pm UTC
Location: North of England

Re: Harry Potter and the Methods of Rationality

Postby jobriath » Thu Feb 16, 2012 11:10 am UTC

Kisama wrote:Oh, I wonder how a day is defined for the purposes of time-turning? Can you use only 6 hours between midnight of one day and the next, or is there a rolling 24-hour window? I suppose it would have to be the latter, because the actual time of day is completely arbitrary and we have time zones and then how would a time-turner work on the moon?

MOR hasn't committed to having magic be rational yet. It's strongly implied that magic is often pretty damn irrational (the Mokeskin pouch) so maybe the concept Midnight is crucially important to the timeturner, even if that would be pretty stupid, as you say.

A better reason that time-turners don't reset at midnight [time of day] is that if they did it would be possible to travel East in a jet and catch up with tomorrow's midnight sooner than if you'd stayed on the ground. A fast enough midnight-to-midnight trip (<6 hours) and you'd be able to go back arbitrarily far, which Dumbledore seems to think is impossible. Air traffic control would be a nightmare, though.

User avatar
Argency
Posts: 203
Joined: Wed May 19, 2010 12:43 am UTC
Location: Brisbane, Australia

Re: Harry Potter and the Methods of Rationality

Postby Argency » Thu Feb 16, 2012 11:19 am UTC

jobriath wrote:
Kisama wrote:Oh, I wonder how a day is defined for the purposes of time-turning? Can you use only 6 hours between midnight of one day and the next, or is there a rolling 24-hour window? I suppose it would have to be the latter, because the actual time of day is completely arbitrary and we have time zones and then how would a time-turner work on the moon?

MOR hasn't committed to having magic be rational yet. It's strongly implied that magic is often pretty damn irrational (the Mokeskin pouch) so maybe the concept Midnight is crucially important to the timeturner, even if that would be pretty stupid, as you say.

A better reason that time-turners don't reset at midnight [time of day] is that if they did it would be possible to travel East in a jet and catch up with tomorrow's midnight sooner than if you'd stayed on the ground. A fast enough midnight-to-midnight trip (<6 hours) and you'd be able to go back arbitrarily far, which Dumbledore seems to think is impossible. Air traffic control would be a nightmare, though.


I always thought this was a hint at how the time turners worked:

Today's historical tidbit: The ancient Hebrews considered the boundary of a day to be sunset rather than dawn, so they said "evening and morning" not "morning and evening". (And as many reviewers noted, modern Jewish halacha asserts the same.)


Source: http://www.fanfiction.net/s/5782108/15/ ... ationality
Gonna be a blank slate, gonna wear a white cape.

User avatar
WarDaft
Posts: 1583
Joined: Thu Jul 30, 2009 3:16 pm UTC

Re: Harry Potter and the Methods of Rationality

Postby WarDaft » Thu Feb 16, 2012 11:47 am UTC

Time Turners are enormously anthropocentric.

There is absolutely no logical reason that the limit should be exactly 6 hours.

There is no reason that the Time Turner should only present you with information that you cannot use to obtain that information - which is definitely true in MOR. Consider all the paradox warnings, Harry's failed factoring attempt, the fact that people can still obtain some information from the future, and can do things that will only be successful if they in fact are going to be successful such as Harry escaping the dungeon after being locked in. Harry could not have gotten out and gone back in time to send anyone a note if he did not end up successfully getting out and going back in time to send someone a note.



Hmm, I wonder if that is a big enough distinction to make prime factoring work. You get a time-locked safe (and set it to open in 8 hours) and also set it to open if given the factors to a number it is displaying. Lock your Time Turner in the safe, and then, if you find a note containing two prime factors, enter them into the safe. If it opens, you can then go back in time and leave the note with the correct prime factors, if it doens't, then you can't. In this case, the numbers on the note are like Flitwick coming to rescue Harry. Only if you get them does the time travel actually happen, and the notion of getting the wrong numbers is nonsensical... you couldn't have sent them if they weren't right. This still involves the appearance of information out of no-where, but then the Time Turner has already done that: "... spoken by a hollow voice that belled forth from a gap within the air itself, a gap that opened upon a fiery abyss!" This phrase is never uttered for the 'first' time, only told by someone who has heard it to someone who has not. So information from a Time Turner clearly does not need to be grounded anywhere.

Of course, it's still not guaranteed, and you'll have to be prepared to wait 8 hours to get your Time Turner back when you first try it.
All Shadow priest spells that deal Fire damage now appear green.
Big freaky cereal boxes of death.

not baby Newt
Posts: 110
Joined: Wed Feb 03, 2010 11:30 pm UTC

Re: Harry Potter and the Methods of Rationality

Postby not baby Newt » Thu Feb 16, 2012 11:52 am UTC

Kisama wrote:Oh, I wonder how a day is defined for the purposes of time-turning? Can you use only 6 hours between midnight of one day and the next, or is there a rolling 24-hour window? I suppose it would have to be the latter, because the actual time of day is completely arbitrary and we have time zones and then how would a time-turner work on the moon?

I doubt it is strictly 24 hours between activations, because there would have been situations like 'I cannot use it at 9.03 pm because I went back the full six hours at 9.04 pm yesterday'.


Something I dont get in chapter 60:
Spoiler:
In a deserted side-road of Diagon Alley, where scraps of un-Vanished trash could be seen lodged into the edges of the brick street and the blank brick building-sides that surrounded it, along with scattered dirt and other signs of neglect, an ancient wizard and his phoenix Apparated into existence.

The wizard was already reaching within his robes for his hourglass when, in habit, his eyes jumped to a random spot between the road and the wall, to memorize it -

And the old wizard blinked in surprise; there was a scrap of parchment in that spot.

A frown crossed Albus Dumbledore's face as he took a step forward and took the crumpled scrap, unfolding it.

On it was the single word "NO", and nothing more.

Slowly the wizard let it flutter from his fingers. Absently he reached down to the pavement, and picked up the nearest scrap of parchment, which looked remarkably similar to the one he had just taken; he touched it with his wand, and a moment later it was inscribed with the same word "NO", in the same handwriting, which was his own.

The old wizard had planned to go back three hours to when Harry Potter first arrived in Diagon Alley. He had already watched, upon his instruments, the boy leaving Hogwarts, and that could not be undone (his one attempt to fool his own instruments, and so control Time without altering its appearance to himself, had ended in sufficient disaster to convince him to never again try such trickery). He had hoped to retrieve the boy at the first possible moment after his arrival, and take him to another safe location, if not Hogwarts (for his instruments had not shown the boy's return). But now -

"A paradox if I retrieve him immediately after he arrives in Diagon Alley?" murmured the old wizard to himself. "Perhaps they did not set in motion their plan to rob Azkaban, until after they had confirmed his arrival here... or else... perhaps..."

Shouldn't wizard or paper travel in time at some point between reading a message from yourself and writing it?

User avatar
Yakk
Poster with most posts but no title.
Posts: 11129
Joined: Sat Jan 27, 2007 7:27 pm UTC
Location: E pur si muove

Re: Harry Potter and the Methods of Rationality

Postby Yakk » Thu Feb 16, 2012 12:44 pm UTC

His next step, not show, is to travel back in time and plant it. Possibly this ritual is intended to make paradox cancelling easier (on the wizard, ie not require death of same, for example).
Last edited by Yakk on Thu Feb 16, 2012 5:00 pm UTC, edited 1 time in total.
One of the painful things about our time is that those who feel certainty are stupid, and those with any imagination and understanding are filled with doubt and indecision - BR

Last edited by JHVH on Fri Oct 23, 4004 BCE 6:17 pm, edited 6 times in total.

User avatar
WarDaft
Posts: 1583
Joined: Thu Jul 30, 2009 3:16 pm UTC

Re: Harry Potter and the Methods of Rationality

Postby WarDaft » Thu Feb 16, 2012 4:59 pm UTC

Another possibility, is simply having another Time Turner that you can enchant to go back in time and drop off a message for you. I mean, that would probably be one of the first things I tried to do were I a wizard with a Time Turner. Yes, you can go back in time and send yourself a message. Or you can just send the message back and not spend an hour waiting to catch up with the present. Another one of the first things I would do would be to find out what it was like to have a conversation with myself and shake my own hand. There's no particular reason this should cause a paradox. Of course it's possible time works specifically to ensure that doesn't happen, but then there would be no one who had accidentally met themselves to find it disconcerting - it wouldn't even be something you had to warn people about.
All Shadow priest spells that deal Fire damage now appear green.
Big freaky cereal boxes of death.

User avatar
Kisama
Posts: 137
Joined: Tue Jan 20, 2009 5:52 am UTC
Location: (0, 0, 0)

Re: Harry Potter and the Methods of Rationality

Postby Kisama » Fri Feb 17, 2012 6:51 am UTC

WarDaft wrote:Another one of the first things I would do would be to find out what it was like to have a conversation with myself and shake my own hand. There's no particular reason this should cause a paradox. Of course it's possible time works specifically to ensure that doesn't happen, but then there would be no one who had accidentally met themselves to find it disconcerting - it wouldn't even be something you had to warn people about.
Why stop there? You could have 7 instances of yourself present at once :)
cd880b726e0a0dbd4237f10d15da46f4

User avatar
Yakk
Poster with most posts but no title.
Posts: 11129
Joined: Sat Jan 27, 2007 7:27 pm UTC
Location: E pur si muove

Re: Harry Potter and the Methods of Rationality

Postby Yakk » Fri Feb 17, 2012 12:57 pm UTC

If we start from a naive QM position, where the outcome of an event is determined by a sum over paths and consistency with boundry conditions... And assume that time travel is local at each end (well both at once). Then experimenting with paradox is a good way to generate an improbability engine. The stronger you make the paradox attempt, the stronger the anti paradox effect would be. If we also assume some principle of least action, I could imagine making a force appear that could be measured... But your death might require LESS force, and be more local...
Last edited by Yakk on Fri Feb 17, 2012 3:03 pm UTC, edited 1 time in total.
One of the painful things about our time is that those who feel certainty are stupid, and those with any imagination and understanding are filled with doubt and indecision - BR

Last edited by JHVH on Fri Oct 23, 4004 BCE 6:17 pm, edited 6 times in total.

User avatar
jobriath
Posts: 256
Joined: Wed Apr 04, 2007 2:11 pm UTC
Location: North of England

Re: Harry Potter and the Methods of Rationality

Postby jobriath » Fri Feb 17, 2012 3:01 pm UTC

The author posted something relevant about a hypothetical box which could make happen whatever you wanted to happen. So you'd give it the instruction "get my mother out of the fire" and she'd fall out of the window. Luckily, whoever built this box foresaw this kind of thing and implemented a negative-infinity-utility button that resets the timelime and gives you another chance. "Save my mother from the fire." Anyway, the final point is that eventually, the protagonist over-constrains the box, and the simplest solution is to do whatever and just kill the protagonist before he can press the negative-utility button. If anyone remembers this I'd be interested to read it again, though I've had no luck finding it yet.

HonoreDB
Posts: 161
Joined: Tue Feb 06, 2007 4:32 pm UTC
Contact:

Re: Harry Potter and the Methods of Rationality

Postby HonoreDB » Sat Feb 18, 2012 4:27 am UTC

jobriath wrote:If anyone remembers this I'd be interested to read it again, though I've had no luck finding it yet.


http://lesswrong.com/lw/ld/the_hidden_complexity_of_wishes/

User avatar
jobriath
Posts: 256
Joined: Wed Apr 04, 2007 2:11 pm UTC
Location: North of England

Re: Harry Potter and the Methods of Rationality

Postby jobriath » Sun Feb 19, 2012 11:06 am UTC

Thanks! It seems I remembered the illustration but missed the point of the article. It seems to me that the quickest and safest way to build a genie with the proper value function is to become God, which is basically what Harry wants to do.

Seems to me that the time-turner is an Outcome Pump with all paradox timelines set to probability 0 and the distribution over the remaining timelines being unclear. Experimentation to determine the precise distribution is prohibitively expensive and experimentation to approximate the distribution is absurdly dangerous (especially 'cos a scientist should test the cases where they guess things will go predictably wrong). Clearly the best and most sound advice is DO NOT MESS WITH TIME.

Maybe we could try to figure out the time-turner's distribution over timelines in vague terms. It seems to "like" not surprising people unless people try to trick it. (Harry studying quietly in his trunk has yet to mess up.) It doesn't seem to mind complexity, from the way it permitted Harry to play the Game.

Why did factoring a large number piss it off so much?

Edit: Since Azkaban is the only place we know of that has some degree of immunity to time travel madness, and we know that Harry has a time-turner, we have to conclude that the safest place to be in the wizarding world is inside Azkaban.

HungryHobo
Posts: 1708
Joined: Wed Oct 20, 2010 9:01 am UTC

Re: Harry Potter and the Methods of Rationality

Postby HungryHobo » Sun Feb 19, 2012 11:11 pm UTC

I was under the impression that in his test he simply didn't constrain the possible messages he could send back. it will settle into the most stable loop and the loop where he gets the answer is stable but the loop where he gets a message so scary that he repeats it will also be a stable loop and if it's more stable then that's what will happen.

to put it another way, there's a very small chance that a harry getting the correct answer may decide to experiment further and try sending some odd message to see what happens with the loop. a harry getting a strange message may send anything, eventually a harry sends a message which would worry harry so much that he'd repeat it exactly and that's what you get.
Give a man a fish, he owes you one fish. Teach a man to fish, you give up your monopoly on fisheries.

User avatar
Jorpho
Posts: 6290
Joined: Wed Dec 12, 2007 5:31 am UTC
Location: Canada

Re: Harry Potter and the Methods of Rationality

Postby Jorpho » Mon Feb 20, 2012 4:39 am UTC

HonoreDB wrote:
jobriath wrote:If anyone remembers this I'd be interested to read it again, though I've had no luck finding it yet.
http://lesswrong.com/lw/ld/the_hidden_complexity_of_wishes/
I am in awe of Mr. Yudkowsky's ability to run so many of these ingenious little thought experiments. Why is he not yet a household name?

AlexRose
Posts: 38
Joined: Mon Sep 14, 2009 2:37 am UTC

Re: Harry Potter and the Methods of Rationality

Postby AlexRose » Mon Feb 20, 2012 7:11 pm UTC

We should ask Mr. Yudkowsky to visit and act as a time-turner. I feel we'd make more progress with some experimental data.


Return to “Books”

Who is online

Users browsing this forum: No registered users and 3 guests