Edit: New thread posted here

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 86The previous thread  has long passed 500 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: 123456789101112131415, 16.

As a reminder, it’s often useful to start your comment by indicating which chapter you are commenting on.

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Eliezer Yudkowsky which is not supposed to be publicly available (which includes public statements by Eliezer that have been retracted).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.


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I was thinking that as of this chapter, Harry now had enough evidence to promote to attention the hypothesis that Quirrell is actually Voldemort. He has reason to believe that Voldemort has access to a mechanism which allows him to take control of people and give them a portion of his power, and Quirrell's apparent backstory entails his having undergone a conspicuous increase in apparent competence, much like that which Moody and Dumbledore suspect of having happened to Lockheart. And he has the assurances of the Order of the Pheonix that Voldemort was really smart, no, seriously smart, trust us, you're still underestimating him. And he knows Quirrell is heavily misanthropic and cavalier with people's lives, and also he went out of his way to remove Voldemort's premier servant from Azkaban, who might be useful to other enterprising wizards if she was taught some of the lore of Salazar Slytherin, but also, as Harry has been told, is a key component in restoring Voldemort to power.

But then it occurred to me that given the fact that Quirrell's sudden spike in competence in his backstory occurred while Voldemort was still around, not after his death, he would have to draw the conclusi... (read more)

Primary piece of evidence against: Voldemort tried to kill Harry,

I don't think we know that.

I've always thought it would have made more sense in the original series to have Voldemort purposely make Harry into a Horcrux.

If making someone else a horcrux transfers some of your power to them, that makes them stronger, and better able to defend your horcrux.

It starts to look like a mutual immortality defense league. A bunch of people get together making each other their horcruxes, so that they all can't die without all the others being killed first, they all have an interest in protecting each other, and they conserve the power that they'd otherwise lose to the creation of the horcrux by contributing it to another member of the defense league.

We don't know that Voldemort tried to kill Harry, but Harry has much less reason to doubt it than we do. An Immortality Defense League sounds much cleverer to me than what we actually see if Voldemort was trying to make Harry into a horcrux, which is a guy making a horcrux out of the infant child of his own enemies. That sounds a lot less tactically sound than willfully perverse; of all the people he could have deliberately made into horcruxes, I don't think he had good reason to single Harry out as being a good choice to ensure his immortality. The only reason I can think that he would have had to single him out would be the prophecy, and that the sort of information where I would immediately wonder, in his place, if by horcruxing my own prophesied enemy, I would actually end up screwing myself over.
I think so too, if I do say so myself. I hadn't thought of the IDL until this thread. Harry as a horcrux seems like a decent idea, though. If Harry were the only guy that could kill you, making it so that he can't kill you seems like a good idea. Also, he has a bunch of horcruxes in objects. Diversifying your strategy seems like a decent idea to me. Making one of your enemy, who everyone else will be busy protecting, enlists them in protecting your Horcrux. Also, I just thought canon was dumb having Voldie killed because Mommy unknowingly invoked some "old magic" through her love for Harry. Anything is better than that pap. EY seems to be rectifying that, writing a more believable plot line. First, he offers a plausible route for Voldie's destruction through intentional ritual magic by Lily orchestrated by Dumbledore. Second, I don't think EY will have Voldie destroyed by the unknown thing he did to Harry. I think Voldie recognized Dumbledore's ritual magic ploy and decided to go along with it and pretend to be destroyed.
But he only has a prophecy's word on that, and attempting to cash in on prophecies that way has a tendency to bite you on the ass (tvtropes links).
It's been implied elsewhere, but I'm pretty sure that in HPMOR, Voldemort has specific plans for Harry that go beyond merely killing him, which included him deliberately being made into a horcrux. Some evidence for this: the odd italicized text fragments in the early chapters (which Eliezer has emphasized), Harry wondering many times at the convenience of Voldemort's supposed death, and repetition of the idea that Voldy should have a) known about sacrifice/dark rituals such as are involved in sacrificing yourself for somebody else and b) have had other, better, more guaranteed ways of killing Harry if that's what he had wanted to accomplish. Actually, further to that, I really think Voldy was intentional with the whole horcrux thing, as shown by the set-up of giving Lily the chance to escape. One possible reason for this is for Snape's loyalty; another, which I consider more probable now, is that if she was going to die anyway it wouldn't have counted as a sacrifice for the purposes of the (horcrux) ritual.
One person's modus ponens is another person's modul tollens. Reading this chapter made me update that Voldemort actually never tried to kill Harry. * He came for Harry (but he never said he came to kill him), probably motivated by the prophecy. * He killed everyone around (but he gave Lily a chance to leave). * He did something that resulted with scar on Harry's head. * Then someone (who exactly, if the event had no survivor besides a baby?) spread a story about how reflected death spell killed Voldemort. * And since then, nobody has ever seen Voldemort again. From more recent history (Quirrel's description and self-description -- although he could have lied to us/Harry) we can reason that: * Quirrel enjoys company of smart people. * Quirrel enjoys role-playing; but he recently prefers role-playing a good guy, because villains naturally attract insane people. * Quirrel does not hesitate to kill people who cross his path, but that is instrumental, not a terminal value. * Quirrel is very, very smart. So I guess that Voldemort, after hearing the prophecy, did not panic and try to kill Harry (unlike the Canon!Voldemort). Assuming that Voldemort/Quirrel is extremely smart and he knows how the prophecies work, he could expect that trying to kill Harry -- without "marking him as his equal" first, whatever that means -- would somehow magically fail, and that is an unnecessary risk. Perhaps the original plan was to simply take Harry and raise him as a Sith apprentice; to make him Voldemort's equal in skill, but also charm him into a smarter version of Bellatrix Black. (Converting is better than killing, because you gain an ally; like Harry later tried with Draco.) But during the action he realized that people expect him to kill Harry, and that this could be a convenient way to get rid of the Voldemort persona. So he just -- made Harry his horcrux? performed on him a brain surgery to raise his IQ? -- and disappeared, pretending to be dead; only to return to Harr
I tend to think any line of action which ends up with Riddle losing his body and having to fall back on his horcruxes, given that he apparently wants his old powers back based on his efforts to get at the ingredients to revive himself and/or the Philosopher's Stone, probably contained some element of accident. Also, the act of training his prophesied enemy, one of whom is bound to vanquish "all but a remnant" of the other, doesn't sound like a great way to serve his own interests. It's not like he's likely to subvert the prophesy and gain a powerful ally, it's just another avenue to empowering the person who's his greatest threat. If I were in Quirrell's place, and knew about the prophesy, I would be wondering "in what way can I ensure that whatever person this prophesy refers to will be least likely to be able to defeat me, assuming our conflict is inevitable?" Keeping in mind that if I try too hard to make a candidate into a nonviable threat, the prophesy will probably turn out to be referring to someone else.

Professor McGonagall looked like she was in pain. "Alastor - but - will you teach the classes, if -" "Ha!" said Moody. "If I ever say yes to that question, check me for Polyjuice, because it's not me."

Did anyone else laugh out loud at that line? :-)

Another subtle point that was full of win:

"I cannot believe that guy's reaction time," Harry said, brushing off his Cloak as he stood up from where he'd been lying invisible on the floor, unseen by his previous self. "I can't believe his movement speed either. I'm going to have to figure out some way to zap him without speaking an incantation that gives it away..."

The "I can't believe it" is because it's not true - this is the moment he figures out Moody can see him when invisible.

I laughed at the face value of it, but I just realized the Goblet of Fire reference now. That's even funnier.
That one didn't hit me until after I finished the chapter.
Only realised now...

This chapter, and the update to Chapter 85, are both fantastic. I hadn't noticed until now that Moody is the avatar of being pessimistic enough that your expectations overshoot and undershoot reality appropriately often (in the same way that Fred and George are the avatar of Aumann's agreement theorem), and I'm wondering what other avatars I'm missing.

This won't exactly be a new observation, but one thing I really like about reading MoR is that some of the most important events involve characters updating their beliefs, and in pretty much any other story the only way this happens is when characters announce themselves or other characters doing this, e.g. "Aha! So it was you who killed Prince So-and-so! You traitor!" and instead MoR characters update their beliefs inside their heads like sensible people and the reader has to figure out the nature of the update for themselves. I don't think I've seen this happen in any other story I've read, it is a great rationality exercise, and I more or less completely missed it the first time I read through. (That is, I noticed Harry doing a lot of updating because it's text instead of subtext, but it didn't occur to me that I would understand the story better if I kept track of updates going on in minds other than Harry's.)

Moody is the avatar of being pessimistic enough that your expectations overshoot and undershoot reality appropriately often

It's funny that Quirrel ought to be that too, because he's hyperrational and reliably cynical about people, and yet his backstory is that he failed to conquer England because he wasn't cynical enough and thought people would follow a Light Lord instead of backstab him.

Actually, I see a significant (at least 10%) chance that the person currently known as Quirrel was both the 'Light Lord' and the Dark Lord of the last war. His "Voldemort' persona wasn't actually trying to win, you see, he was just trying to create a situation where people would welcome a savior...

This would neatly explain the confusion Harry noted over how a rational, inventive wizard could have failed to take over England. It leaves open some questions about why he continued his reign of terror after that ploy failed, but there are several obvious possibilities there. The big question would be what actually happened to either A) stop him, or B) make him decide to fake his death and vanish for a decade.

Actually, I see a significant (at least 10%) chance that the person currently known as Quirrel was both the 'Light Lord' and the Dark Lord of the last war. His "Voldemort' persona wasn't actually trying to win, you see, he was just trying to create a situation where people would welcome a savior...

This is exactly how I read chapter 85, and now 86 confirmed it. My estimate is way over 10%, probably ~60%.

Same. Though... what about Tom Riddle?
What about Tom Riddle? He grew up, decided to conquer Britain, and, being clever, played both sides to do so.
So, in other words, he lost twice.
Evil overlord list rule 230 is "I will not procrastinate regarding any ritual granting immortality.". Which he's shown to be aware of. It makes sense, remaining evil overlord allows him access to all the materials of dark rituals and willing assistants, once he's achieved it successfully he has all the time he would like to do anything else.
I've suspected something like that at least since Quirrell gave his speech at the end of the armies sequence, and 86 just gave me a lot of new evidence for it. By now I'd say my estimate is somewhere in the neighborhood of 80% for him playing both sides in a similar sense, though I don't think we have enough evidence to narrow it down to playing Light Lord as such -- just to set up a situation where a Light Lord would need to arise.
This is certainly the obvious or surface theory that the text presents, and I believe in it too. But that doesn't change Quirrel's backstory; he played the role of Light Lord, and people didn't rally round him.
One caveat - while Voldemort did seemingly try to set himself up as a Light Lord, the closest to such that actually existed in the end was Dumbledore. I think it's safe to assume that Voldemort is not Dumbledore.

Although, actually, that would be kinda impressive.

I mostly wrote that comment as an excuse to write the last sentence, truth be told. It's an interesting enough theory(even if obviously wrong in this case) to make me wonder if any fics exist with it as a premise.
OR IS HE? No. No, he's not.
That's ... far from certain.
Somehow I don't think Moody would make that mistake.
It's pretty clear that whatever the reason Moody hasn't got a phoenix, it's not that he's not willing to solve problems right away by applying overwhelming force to a defenseless (but evil) enemy. And why hasn't he tried to become a Light Lord with a Light Mark on an army of personally loyal Aurors? Maybe he more enjoys the thrill of the chase than rationally plots how to rid the world of Dark Lords.

And why hasn't he tried to become a Light Lord with a Light Mark on an army of personally loyal Aurors? Maybe he more enjoys the thrill of the chase than rationally plots how to rid the world of Dark Lords.

Maybe because he has enough experience to know how much attempting to make himself any kind of Lord would increase his chances of getting killed.

Now that is a much better reason than "because Light Lords inevitably become corrupted and Dark".
Because that is how you become a Dark Lord.
Based on what? We know of only one such (alleged) case and that is Grindewald. Other Dark Lords have tended to start out Dark, thanks to Rowling's apparent beliefs about evil being intrinsic and unchangeable. Anyway, I'll take a corrupted Light Lord over a deliberate Dark Lord any day of the week.

I suppose this is where I need to make the obvious quotation:

If we must have a tyrant a robber baron is far better than an inquisitor. The baron's cruelty may sometimes sleep, his cupidity at some point may be sated; and since he dimly knows he is doing wrong he may possibly repent. But the inquisitor who mistakes his own cruelty and lust of power and fear for the voice of Heaven will torment us infinitely more because he torments us with the approval of his own conscience and his better impulses appear to him as temptations.

It's a nice quotation, but where's the actual evidence? Has anyone shut up and multiplied and calculated the net value of trying to become a Light Lord? At least some of them must do good.
Generally, people are too diverse to allow you to lord it over them without some serious force being used on dissidents, at which point you're not very Light anymore. The extreme case of this is people like Pol Pot or Robespierre, and Grindelwald is as good a fictional avatar of that sort as any. Now, there are historical examples the other way - Cincinnatus, for example. But most of them you'll find will either have been given their power instead of seizing it(which is obviously a lot less likely to cause violence), or they'll turn out to be a lot less nice upon closer inspection.
Being a Light Lord doesn't necessarily mean ruling ordinary people and making laws. Unless you're like Harry and want to change existing laws a lot. Being a Light Lord is about leading people in the fight against evil and Dark Lords, but only a few people are fit to fight like that. For that matter, Dumbledore is a pretty good Light Lord, his goals just happen to be different from Harry's.
If you want to be a moral leader, you can do that and stay Light pretty easily - Gandhi is perhaps the archetype here. But few would consider him a Lord. When you go from consensual means(which are nice, but only ever affect a portion of society) to forcible means(which affect everybody, but are not nearly so nice), you're threading a needle to remain the good guy while you're doing it. It can be done - murder laws are forcible, but I think we can all agree they're good. But it's rare.
Going back to the source, chapter 20: If Harry set about changing effective physical laws by magical means, he would be far removed from day-to-day literal lording it over the common people.
Do you think that gods are less powerful than politicians? Good intentions and unlimited power are not always a good combination. I would trust Harry with literal omnipotence more than most people, but he's far too arrogant to be trusted with enormous-but-not-unlimited power, of the sort where he can screw things up better than he can fix them. Have you ever read Brandon Sanderson's Mistborn books, by chance? There's a character who I'm very much reminded of by this conversation. (Spoilers from the first 3 books follow) Gur ybeq ehyre jnfa'g ernyyl n avpr zna, ohg ur jnf npghnyyl n tbbq thl va fbzr vzcbegnag frafrf bs gur jbeyq, naq ur yvgrenyyl hfrq gur Jryy gb fnir gur jbeyq. Ohg uvf fnivat bs gur jbeyq nyfb erdhverq gur rasbeprzrag bs n gehyl njshy srhqny fbpvrgl, jvgu mbzovr nezvrf(gur xbybff), abovyvgl jub jrer rkcrpgrq gb encr crnfnagf naq yrtnyyl erdhverq gb zheqre gurz nsgrejneqf, naq greevoyr crefrphgvba bs uvf bja crbcyr. Naq guvf jnf yvgrenyyl gur orfg ur pbhyq qb gb fnir gur jbeyq, orpnhfr bapr ur unq zbqvsvrq gur jbeyq gb cerirag vgf qrfgehpgvba, uvf cbjre gb punatr vg shegure jnf tbar. Naq va gur raq, ur ehyrq bire uvf perngvba sbe n zvyyraavhz, hagvy ur jnf zheqrerq ol na natel qvffvqrag orsber ur pbhyq znxr vg evtug. Fnmrq vf npghnyyl bzavcbgrag(be ng yrnfg, nf pybfr gb vg nf ur arrqf gb or), fb Fnmrq pna svk uvf zvfgnxrf, ohg gur Ybeq Ehyre jnf genccrq ol uvf bja fhpprff. V jbeel terngyl gung Uneel zvtug jvaq hc n ybg zber yvxr gur Ybeq Ehyre guna yvxr Fnmrq vs ur fgnegf zrqqyvat jvgu gur ynjf bs gur havirefr.
I'm not sure I'd even trust him with omnipotence, since presumably even an omnipotent agent is still bound by the laws of logic and mathematics. In any case omnipotence without omniscience, at least, strikes me as recipe for disaster.
It's kind of there in the name: Light Lord. More generally, any radical change in society's moral nature will require changes to a lot of laws.
Again, changing people's moral nature is just one thing a Light Lord might want to do. It's not even something Harry really wants to want to do. If a Light Lord was known for e.g. developing amazing new medicinal magic, prolonging average lifespans, giving everyone in the world a hundred Galeons, developing faster broomsticks, or changing the laws of physics to discourage murder - but all the time just ignoring human laws - then they could definitely do so without antagonizing the legal authorities.
You are abandoning all the connotations and denotations of the phrase. Light Lord is explicitly intended to be a parallel to Dark Lord - and there aren't really Dark Lord parallels to the activities you listed (particularly while complying with your important caveat to avoid "antagonizing" legal authorities).
There's no point discussing what the phrase Light Lord "really" denotes. Clearly I understood it differently from everyone else in this conversation, so inasfar as it has a correct meaning, you're right about it and I was wrong.
He wouldn't be good at it, would he? His role is purely defensive - thwarting and removing evil wizards without croaking in the process. There's little evidence he can plot that well, or lead a group that isn't a smallish team of fawning younger Aurors.
He's very offensive on the tactical level. If that sums up to defensiveness on the strategic level, that seems like it should tell us something about Dark Wizards being better strategists than the Light ones.
Well, duh. It's easier to gain and keep power than to gain and keep power and also improve the world and never do anything too unethical.
Or the idea isn't as great as Harry seems to think it is. Moody knows a LOT more about the world and the wizarding world. I'm sure he can remember plenty of dark Lords that started out as light lords, for one.
Where do you get that idea from? Apart from the single example of Grindewald. Besides, Moody wouldn't go Dark because he's got ETERNAL VIGILANCE on his side.
Isn't a bad Light Lord pretty much exactly what Dumbledore fears? That suggests historical precedent, to be so worried after just a few months of Harry.
From Dumbledore's words to Harry, I gathered that he was more afraid Harry might become a Dark Lord more directly without a significant Light Lord phase in between. I don't think he has the concept of a Light Lord present - great wizards are to him either Dark Lords or those who oppose them, not Light Lords who do something positive and unrelated to any Dark machinations. Also, I don't trust Dumbledore in particular to make a fair assessment, since he's the one most liable to be swayed by the single example of Grindelwald.
Avatarwise: Dumbledore seems to be humanities/iberal arts/romantic ideals. Snape is (maybe?) undiscriminating cynicism. [retracted]

I don't think an avatar of undiscriminating cynicism spends more than a decade pining for his crush that got away.

True, that doesn't fit as well. Its not quite an avatar, but his defining trait seems to be dramaticness, he shapes his life around his past mistakes. In contrast to Dumbledore who thinks in heroic tropes he thinks in tragic ones.
Didn't get that until just now.

Harry is slowly updating on the evidence that the wizarding community is not as grossly incompetent as he originally believed.

I agree and it is extremely fun to watch happen to a character. All Harry's private scenarios of how to take over magical Britain in five minutes are a perfect example of his main character flaw: arrogance, or, his dismissiveness of the realities of politics as superfluous, "people stuff." It should be clear to the reader, anyway, that liberal use of Imperius would NOT be sufficient to take over the government, at least not for any meaningful length of time. Harry is making the same type of error that led to Voldermort's original failure, that is, modeling people as being simpler and dumber than they are, likely due to his own sense of superiority.

Totally unrelated, but I wanted to mention somewhere (and didn't think it worth making a new comment) that I laughed harder at "I once arrested a young Japanese who tried a similar trick. He found out the hard way that his shadow replica technique was no match for this eye of mine." than I have at anything in recent memory. (It is a Naruto reference.)

Moody has a magical eye. Therefore, Naruto has at some point fought him. QED.

Not just that. I believe naruto has fought (or was it will fight?) all doujutsu. Word of God.
Yeah, but that one specifically is the best match for the Eye of Vance.
2Eliezer Yudkowsky11y
I tried to write a line with Harry misidentifying it as the Eye That Looks Toward The Sun but had to take it out.
Sorry, you lost me (and the term doesn't seem to be googleable). What's that a reference to?
1Eliezer Yudkowsky11y
Hyuuga = "Toward the Sun"
Damn. I already upvoted this, so now I've actually read that scene, I can't righteously upvote. Also, seconding moridinamael; Moody's Naruto line was pretty damn hilarious. Though now I'm wracking my brains trying to remember whether 'no match for this eye of mine' is lifted directly from Naruto, or you were just successfully emulating shonen braggadocio. https://www.google.com/search?q=conic+frustum

Remember that, in canon, Voldemort does indeed take over the Ministry with a few Imperiuses and a few assassinations.

I think this is more Eliezer once again obliquely making fun of how shallowly Rowling imagined her own universe, that its government could be broken by essentially any individual wizard of moderate power.

Well, and the fact he had support form a number of rich high ranking people and his own terrorist group to deal with any resistance after the fact.
Unless Eliezer has deliberately depowered Imperious - which isn't impossible - or given the Ministry some sort of get-out-of-Imperius-free-card - which is also possible, what with the Ministry being created almost exactly in it's present form by Merlin, a significant change from canon - then liberal use of Imperius cold absolutely take over the government. My theory is that "Voldemort" was deliberately playing the role of the Evil Monster who's about to take over the world, but never does; perhaps in an attempt to have Wizarding Britain unite against him.
Considering that Eliezer says in the notes that he "regret[s] that [he] could not come up with any reasonable way to have Harry shout 'Temporal fugue!' or 'Kage bunshin no jutsu!' before attacking", this is almost certainly a Naruto reference.
OK, so there are Moody and Voldemort, but pretty much every other wizard ever is grossly.incompetent. Any normal Moogle SF fan thinking for an hour, or Harry Potter thinking for five minutes, could run strategic circles around them and kill half of all Dark Lords who ever lived by owling them bombs. Better?

OK, so there are Moody and Voldemort, but pretty much every other wizard ever is grossly.incompetent.

No — they simply have not chosen to prove themselves to Harry, the viewpoint character.

I expect we'll find, soon, that Harry's model is wildly out of whack — adult wizards are, by and large, competent but flawed, especially the leaders and heroes. They simply do not let on to children everything they can do, nor their level of control over the world. Why? Because gifted children are not really all that rare, and teaching kids more magic than they are responsible enough to cope with is how you get Dark Lords — and dead kids.

Expanding on this — The purpose of magical education (e.g. Hogwarts) is not to teach kids as much magic as possible, to enable them to fix the world as Harry wants to do. The purpose of magical education is to safely and gradually expose them to magic, to maintain the current status quo and certainly to prevent any dumbass kids from destroying the world or killing each other. It also includes giving them chances to prove themselves responsible and skilled enough to wield more, and to put them in touch with adult wizards who might choose to individually teach more. But none of this is served by powerful wizards flaunting their top abilities in blatant and imitable fashion in front of the kiddies.

Nothing stays secret from teenage kids for long. No conspiracy of a large size can be maintained for very long (especially if it must admit everyone). And the Lucius Malfoys of the world would want to give their kids every advantage.

Parents in the real world want to give their kids every advantage too, but few sign their kids up for calculus class and gun-range time at age 6, you know? Parental conspiracies aimed at preteen children are remarkably resilient things(cf. Santa Claus). Teenagers are harder, but you can rely on most of them not actually wanting to be bothered learning any more than they have to.

Did Draco know about the Secret of Potions?
Did Lucius?
I got the impression it was common knowledge among powerful wizards. Am I misremembering?
If you look back at Chapter 78, it says that Harry had not made an original magical discovery, but rediscovered a law so ancient that nobody knew who had first formulated it: A potion spends that which is invested in the creation of its ingredients. But conversely, it also says that The fundamental principle of Potions-Making had no name and no standard phrasing, since then you might be tempted to write it down. McGonagall and Flitwick seemed to at least be familiar with the idea, though, so there's a good chance that you're right. Edit: I should probably also point out the obvious. If knowing the general rule is "WTF? Stop!" dangerous, like the professors seem to suggest it is when Harry tries it, then it's not generally the sort of thing you'd teach your 11 year old son. There's plenty of time to pass things like that along when the kid's closer to adulthood and mellowed out a bit.
Sure, that's why this is a story written by Eliezer and not (say) Piers Anthony. But still, an educational system does not last for long if it obviously gives every kid a nuclear bomb.
Well, that's true, at least.

could run strategic circles around them and kill half of all Dark Lords who ever lived by owling them bombs.

Harry thought he could figure out who the Death Eaters were by checking their arms for the Dark Mark. Turns out it's not that simple.

Now he (and you) still think that you get rid of a dangerous enemy by owling them bombs. Does either of you even have any reason to believe that there isn't a magical precaution against sending dangerous objects through the owl mail system?

Er, he broke that protection in about five minutes of thought. That's evidence for actually being able to run strategic circles around magical Britain.
Dumbledore did hand him the "You're wrong, think about it for 5 minutes" cue in a way that got him to do it. That kind of thing is crazy helpful.
And yet Dumbledore and everyone else he though of asking couldn't solve it themselves for twenty years. For the last ten years, Snape would have told them if they'd even made the right suggestion.
Like I said, Voldemort is one of the only two or three competent wizards shown. It's more likely that there isn't than that there is, and it's something to be (quickly and easily) tested. This particular example aside, owling bombs isn't intended to be taken literally; it's a stand-in for a simple attack that wizards don't expect. Any particular such attack may not work, but I strongly expect that if Harry dedicated a whole day to thinking up and actually trying such "low-tech" attacks, vetting them with Dumbledore against known defenses to save time, then he could come up with enough attacks to take down at least half the Dark Lords in recent history.
On the one hand, the fact that owl bombs are not a common tactic is itself evidence against the being usable. On the other hand, in canon you could definitely send dangerous objects through the mail.
In the MoR!verse, at least, Dumbledore is screening Harry's mail instead of letting it go to him directly. So "owling hand grenades" won't work against someone who takes precautions to prevent it. The question is whether the target is taking precautions or is simply going to let owls deliver strange packages.
Dumbledore could also screen it for other reasons.
Indeed. Dumbledore told Harry that he would have a hard time (emotionally) dealing with his "fan mail" and Harry pretty much agreed. Whether Dumbledore has any other motive is left as an exercise for the reader.
Meh, Minerva mentions that a trained wizard can deal with a gun, I imagine explosive deactivating spells would be a standard part of your self defence/mail checking spells.
I think it was cannons, not guns :D
Magic bombs. Or other destructive artifacts.
I may be unduly influenced by how its handled in the DAYD fan-verse, but my impression is that wizards understand the concept of a letterbomb and screen for them if circumstances (for example being Mad-Eye Moody) call for it. They just don't do it routinely anymore than normal people do. P.S. I prepared explosive runes this morning.
DAYD? And I wouldn't be surprised if wizards - at least those with know enemies - screen their mail (although this isn't mentioned, and it's apparently unavailable to students.) I was just nitpicking the idea that you couldn't send a Wizard something they would be unable to neutralize with magic once they had it.
Dumbledore's Army and the Year of Darkness, one of the main stories involves anonymous owls.
In the MoR!verse, Dumbledore is screening Harry's mail instead of letting it go to him directly. So "owling hand grenades" won't work against someone who takes precautions to prevent it.
What about the other Aurors during TSPE? I thought they did pretty well overall.
Madam Bones, yes. The others seem average. Not owl-bomb-proof unless they're given regulations about it.
Fortunately, things like that are why bureaucracy exists.
Bureaucracy is self-preserving. It doesn't really have other builtin goals than that.

That sounds like a cached thought. Bureaucracies can be programmed to have relatively well-understood side-effects of their survival. For instance, McDonald's is a bureaucracy that has a side-effect of producing hamburgers; a military is a bureaucracy that has a side-effect of politically inconvenient people getting dead.

That's a good point. My comment was overbroad and oversimplified.
Avoiding assassination is generally considered to assist with self-preservation.
Reminds me of Competent elites. I suspect we'll get some display of the order, Aurors and/or ministry civil service behaving competently soon and Harry updating his beliefs on them. Outside the school setting what evidence do we actually have that the wizarding world is incompetent? [Not just operating self interestedly or on different values.]
Note, the link in your comment is currently a Google link rather than a link directly to the post.
I don't see the issue, shouldn't it redirect instantly? Changed it anyway.
The issue is just that unnecessary intermediaries should be avoided; it wasn't anything more serious than that.
Another one:
I would say that's more reflective of ignorance than incompetence. Though failing to sufficiently inform themselves about dangerous muggle technology would be incompetence at a meta level.
Putting Arthur Weasley in charge of Misuse of Muggle Artifacts, rather than an actual Muggleborn/halfblood, strikes me as incompetence of the highest order. We even see that Minerva took top marks in her Muggle Studies class, but still thinks of herself as ignorant, and she happens to be fairly competent.
Quiditch, the lack of adequate protection on time turners before Harry gave them the idea put protective shell on them... Seriously, just reread the fic.
My point is that the examples we've seen are mainly from Harry's perceptions, he hasn't actually tested any of them. The only one was the partial transfiguration which isn't exactly obvious to anyone else.
Like there's no RL sports with silly rules. And do time-turners actually need protection? The seem to require pretty deliberate action to use, and I assume they're hard to break.
They're hard to break now that they put protection on them. They were rather fragile before.
Admittedly, it says that in HPMOR, but does it in canon? Do we have any examples of them being damaged or destroyed, or any special care being taken with them? It seems odd that Eliezer would change canon to make the ministry stupider, given how they weren't exactly mental heavyweights in canon and his stated goal is to make a plot where everybody is at least generally competent.
First: MoR is what the conversation was about, wasn't it? Second: Yes, in canon they were fragile enough that all of them- all of them- were destroyed by a few stray spells, in the Department of Mysteries Battle.
1) I was wondering whether the implied mockery of canon was reasonable. Apparently it is. 2) Huh, I never noticed that detail reading through. Not sure a protective shell would help with that sort of destruction, though.
I just went and looked up the exact wording in OotP. A missed Stupefy hits a glass cabinet, which falls to the floor, which shatters all the Time-Turners inside (causing some weird stable time loop thing). If the shell can withstand being dropped on the ground, it's a useful improvement.
I always thought of that as more of a retcon than a plot point, JKR telling us "Yeah, ok, in retrospect the time turners were a bad idea, but I'd like to write the rest of the series without having to incorporate or work around them so just roll with it, ok?"
A better patch would be to say time turners only work in Hogwarts as an additional class attendence spell built into the general spells of the school (which canonically does weird things to space anyway).
Yeah, that's obviously the motivation, as is evident from the fact that Time-Turners essentially don't appear outside of one scene in PoA. That doesn't affect the point of their canonical fragility, though.
Oh lord. Okay, you win.
The possibility of gold-silver arbitrage with the Muggle world and the lack of fractional-reserve banking.
I'm very sceptical since the beginning of gold-silver arbitrage with the Muggle, I'm pretty sure it'll be forbidden under the Statue of Secrecy. Interaction with Muggles are not taken lightly. And since you've to go through a goblin bank to get your gold minted, you could hardly do it in a stealthy way.
I suspect galleons are actually a fiat currency controlled by the minstry/goblins, who keep a very close eye on the amounts of Gold in private hands and limit how many new Galleons can be minted.
There's folks in the Muggle world who think that fractional-reserve should be avoided like the plague, too. Perhaps goblins are all Austrian.
Wouldn't this allow others to set up competing banks, or just competing lending agencies, and make good profits?
Mostly, the Austrian response to that seems to be "Go ahead, but I'd never use them". Apparently, full-reserve banks are a service people are willing to pay for. (And they do. They're called "safety deposit boxes".)

I'm a little surprised that HJPEV didn't immediately update his probabilities regarding Quirrell's motives in Azkaban with the new knowledge from Moody that "You've got to mean it. You've got to want someone dead, and not for the greater good, either.", which would seem to discredit the Defense Professor's excuse that "a curse which cannot be blocked and must be dodged is an indispensable tactic."

Not necessarily; someone who's as deeply misanthropic as Quirrell might wish most people dead (having killed before, he can, as per Moody's explanation, wish people dead rather more casually than non-murderers.) If you're already capable of bringing intent-to-kill to bear on pretty much anyone who crosses you, you can probably use it strategically the way Quirrell suggests.

On the other hand, even if Quirrell's explanation holds true, it does suggest Harry should revise upwards his estimates of just how cavalier Quirrell is with other people's lives.

just how cavalier Quirrell is with other people's lives.

Surely Harry already understands that Quirrel places no intrinsic value on other people's lives. Perhaps this understanding is not visceral enough yet, though.

It should already be pretty high though - Harry even points it out at the time (Rule 1 of Unforgivable Curse Safety) and Quirrell equivocates it away by mixing up etiquette rules with safety rules. That might just as easily have ended with "I just shot Bahry in the face" considering how fast the spell must be going - probably <100 ms to recognize he can't dodge in time, and push him away.
The Auror starts dodging as soon as he recognizes the Killing Curse. This probably gives Quirrell a reasonable window of time to judge whether or not his opponent will dodge in time. How large this window is, that's another question. Voldemort can say the incantation in "less than half a second" but the description of that doesn't match the description of the Azkaban scene, so it seems that Quirrell says the curse more slowly. This suggests that either he is telling the truth when he says that he wanted Bahry to dodge, or else Voldemort's skill at tongue-twisters is rare even among capable battle wizards, and he doesn't want Harry to make the connection.
I took this passage as saying that you don't have to be especially pathological to cast the killing curse a second time - Moody explicitly says it "doesn't tell us much". So if we trust him, it doesn't tell us much.
"It takes a cracked soul to cast." and "Murder tears the soul." just says that if you've gotten to the point where you could cast it once, that particular pre-requisite is already accomplished, so the work to crack your soul is already put in. It doesn't say anything about removing the requirement of wanting someone dead. Though, so long as we're looking at evidence, if we take Quirrell at his word, then his ability to cast the spell despite not wanting his opponent dead is pretty strong evidence that the requirement is in fact removed. In fact, we already know that some "requirements" to cast spells are not set in stone: from that same scene, Harry cast the true patronus without the carefully practiced stance and wand twitches, instead merely "one desperate wish that an innocent man should not die -"—but the constant requirement in this case seems to be the thought that accompanies the casting of the spell, which is why I'm hesitant to believe the wish of death is removed from AK's casting requirement.
Harry didn't cast the patronus then, it was already active, he just moved it.
Fair point, though that also removes the point of evidence that casting requirements are removed with practice.
Just because he didn't intend to kill him doesn't mean he didn't want him dead. As Moody said, you have to want it, not just for the greater good, but as an end unto itself. Quirrell might have wanted to kill Bahry as an end unto itself, whereas for matters of convenience it was better to leave him alive.
Yeah, that kind of leaped out. It also made me wonder how Quirrell and Dumbledore thought they were going to teach students the spell.
Killing Curses don't kill wizards, wizards kill wizards!
You don't think you can teach children how to want someone dead for the sake of wanting them dead? Children can be very hateful. (At least, this could be what Quirrell is thinking, and Dumbledore could be thinking or hoping that the children just aren't going to be able to cast it.)

I'm very glad I didn't know that spell when I was little.

In canon, Moody used the unforgivables on a spider, and given the prevalence of ostensibly non-sentient things-to-fear in the magical world (e.g. boggarts), it's conceivable that they could have found a particular magical creature that even the most PETA-supporting student would have no trouble excising from the world. Also, as far as I can tell, there's nothing in canon to contradict that curses' targets are limited to Kingdom Animalia (see also: Harry's existential crisis about sentient plants), and I seriously doubt there are any 7th level vegans at Hogwarts.
How do you level up in being vegan? And what powers does it grant?
It's a reference to an episode of The Simpsons, wherein Lisa's boyfriend states: "I'm a level 5 vegan. I won't eat anything that casts a shadow." Edit2: Primary source found.
Remember that Harry had also learned that Quirrell had successfully used Avada Kedavra on two Death Eaters. Moody says that it isn't hard to cast AK for a second time, and Harry already knows that this time would have been at least Quirrell's third.
I interpreted the ease of casting the spell as a specific application of scope insensitivity rather than a change in the requirement to cast it. That is, while casting it the second time might be just as difficult (i.e. take as much mental/magical/spiritual energy) as the first, the third and fourth time would together be only as strenuous as the first, as would the collective fifth through eighth time, etc. It is already established in-universe that some form of personal mana depletion exists, and my idea of this difficulty reduction is an extension of that form of energy to the spiritual energy (established in canon w.r.t. horcruxes, dementors, etc.).

Now Mad-Eye Moody was turning slowly, always turning, surveying the graveyard of Little Hangleton. [...]

Moody didn't actually need to turn to survey the graveyard.

The Eye of Vance saw the full globe of the world in every direction around him, no matter where it was pointing.

But there was no particular reason to let a former Death Eater like Severus Snape know that.

Some time later:

"You see in all directions," Harry Potter said, that strange fierce light still in his gaze. "No matter where that eye is pointing, it sees everything around you."


Just because he has no reason to tell Snape doesn't mean he has any particular reason to fear the knowledge getting out. He's already earned his spot on the Supremely Dangerous Wizards list. Kinda makes me wonder why he didn't conceal the fact that he has a magical eye at all, though.

FakeSpoiler: Mad Eye actually wears a decoy. The real Eye of Vance is a suppository.

Because it's bright blue, the wrong size, sits in its own special eye socket, and is prone to spinning on its own? It's not like he can play it off as being his own eye, and nobody would believe it's just regular glass. If you want your lies to be credible in future, you can't make obvious ones in the present.

There's a little thing called MAGIC. Also: Eyepatches. It's not like it can't see through them.

I don't have a side view coming up on Google Image, but I thought the eye stuck out of his head pretty far, making any sort of usual eyepatch inadequate for concealing, and custom eyepatches(in the 20th century, when eyepatches are never seen outside of Halloween and period pieces) would just beg the question.
It's hard for me to imagine you're not trolling with that comment. We're talking about an entire culture that dresses in a combination of period garb, fictional accouterments, and ignores almost entirely the "20th century" world around them. No one comments on Quirrel's Turban or Moody's unique to him skull staff. Also: To this day, the 21st century, people sometimes suffer eye injuries and wear eye patches, and they're pretty large Also: Google image search for steampunk eyepatch
Okay, using centuries to describe wizard fashion was a silly thing to do. And I was unfamiliar with serious modern eyepatches - most of the time I've seen something for that purpose, it's either sunglasses of some sort, or an "eyepatch" that's more of a temporary dressing than anything. Though I don't see why a turban would raise eyebrows. Admittedly, white guys wearing them is unusual, but turbans are hardly rare. And everybody knows Moody's a bit of a loon, so...well, I suppose that by explaining why he has his weird headpiece, I'm also arguing for why he could probably get away with an eyepatch if he wanted to. Maybe he got the Eye in a way that was made public despite his best efforts, and so he figured he'd do better to obfuscate its exact powers than to try to conceal its existence?
One could argue both ways. As I recall, he knocked over some third-world (or, since it's magical, negative-third-world) country to loot the artifact from a tinpot dictator. On the one hand, that sounds pretty dang public on the face of it; on the other, he phrases it as 'somewhere he doesn't have to worry about silly rules' (such as "don't hunt down and kill people because you want their things"), implying Britain isn't paying a lot of attention to the place in any event.
What are you talking about? Edit: Ah, that's something they invented for the films.

I think I preferred the old version of 85 more than the new one. "The phoenix only comes once" seems a lot more made-up than Harry's original determination to abandon comic-book morality as soon as someone died, which felt very much in character.

86 is certainly interesting, even if it largely felt like a wrapping-up restatement of what we knew. That said, I loved the Moody duel, and after six months a bit of restatement is quite useful. Also, I'm torn between how to interpret Snape's last question - my first thought was that he was verifying the truth of a story he had been told("Your master tortured her, now join the light side already!" being the most likely), but upon rereading, I wonder if he was worried that she had been used as Horcrux fuel.

The new version was like a shock-glove-plated punch to the gut right at "I thought it was to my death I went". Wouldn't trade anything for that feeling. :)

Greater emotional impact in much fewer words. It actually feels awful, rather than sounding like a drawn-out rationalization. New version wins on both counts IMHO.

I never liked the old version. Harry pretty much admitted to himself that he was making a wrong choice, he expected his attempt to not kill anyone to fail, and yet he still delayed making the right decision because he couldn't accept it emotionally. That is not a superhero of rationality. Frankly, that is not someone to whom a phoenix would come.

I think part of the point of HPMOR is that rationality is hard.

Like people, phoenixes need high but achievable standards, and I think you're setting yours too high.

Phoenix utility functions are not human-friendly; they do time discounting differently from us. It's not that rationality is hard, but that true rationality combined with human values like Harry's does not meet with phoenix approval.

The post-edit Harry decided he would do the phoenix-right thing later. Once he decided that, the phoenix went away, and will not return. If he had decided that firmly earlier, presumably the phoenix would not have come to him in the first place.

The pre-edit Harry struggled with a similar question. To be consistent, I agree that a phoenix could and should have come to him while he was struggling. But once he had made his decision, the phoenix would definitely not come. Those are the phoenix rules, as given by the update to this chapter.

The decision Harry had come to pre-update was that he would not do whatever it took to free the prisoners of Azkaban; and also that he would not do whatever it took to protect his friends and strike down evil, until he allowed another person to die through being ineffective. Those are not decisions a phoenix would approve of. (Which is not to say I don't approve of them.)

What are phoenixes trying to accomplish?

Do they have goals, or just drives? They're implied to be closer to animals than people.

In the same way (in HPMOR canon) Dementors are the projections/personifications of death pheonixes may be the personifications of courage or whatever.

[Maybe there's some sort of magical collective unconscious thing going on?]

Courage doesn't run on a model of "if you fail one test, you'll never get another chance".
Perhaps they are personifications of "The Call To Go On A Magical Quest Requiring Great Courage". But I admit it doesn't exactly roll off the tongue.
"Heroism" seems like a more succinct way of putting that, although it's a fairly specific sense of heroism.
"Heroism" has the same objection as does "Courage": You may get many chances to be heroic. "The Call etc" is a particular trope, and only occurs once per character.
"Campbellian heroism", perhaps. Though strictly speaking a Campbellian hero doesn't have to be a conventional hero -- the Thousand Faces/Hero's Journey pattern is more about growing into your potential than about saving people or defeating a specific Big Bad -- and both seem to be indicated here. As I think I've said before, the specific construction of heroism that MoR is using seems to inherit a lot from Fate/stay night, and more specifically from the "Fate" and parts of the "Unlimited Blade Works" routes. The concept we're pointing to usually gets translated there as "superhero" or "hero of justice", but I'm not sure what the Japanese is, and in any case I've no idea if Nasu was using a conventional phrase or if he's using a specialization of a more general word the same way we are.
True, but death doesn't wear a cloak etc. The personifications of a concept don't necessarily have to model it perfectly,
Maybe there's a limited supply of phoenixes and they just figure they can find better heroes if they keep trying out new people.
How so? So far as I can tell, in this war, nobody has died, and since we don't know it's a war against Voldemort again, we don't know that it's part 2 of a war where a lot of people did. Now, there's a good chance that the war will result in deaths, but "I should go around killing innocents if needed to win the war" is a pretty extraordinary statement, and I won't fault him for requiring fairly ordinary evidence to make it.
A war means people risk death, Voldemort or not. The last plot tried to have Hermione die in Azkaban, and (since Harry doesn't believe Quirrel did it) seemed designed to kill Draco right away; the next plot may succeed. And people are dying in Azkaban all the time, second by second. Pre-edit Harry was unwilling to commit to killing as an acceptable instrumental goal given a sufficiently high payoff. Making a goal sacred and of infinite value, while also wanting to balance it with other terminal values, is a contradiction. Harry realized this, and did it anyway, and that is a rationalist sin. He disobeyed the rule that "if you know what you're going to think or do later, you should think or do it now". Post-edit Harry is willing to commit to killing if that's what it takes. He asks Moody not to harm the suspect if possible, but he doesn't say they should not attack him if they expect to have to harm him. He is both a better rationalist and a better person.
Harry's discussion with Moody in 86 didn't bother me. I'm referring specifically to the old version of 85. And remember that the vast majority of conflicts in the world don't turn out to be "war" - thus far, we've had one attempted murder and a jail that's basically a worse version of a stereotypical third-world oubliette. That's well within the realm of things police deal with on a regular basis. Police don't generally give themselves license to, say, burn Narcissa Malfoy alive. (Anybody have a copy of old-85? I'd like to see the exact phrasings of it if possible, for continuing this discussion)

(Anybody have a copy of old-85? I'd like to see the exact phrasings of it if possible, for continuing this discussion)

"What's that, Lassie? Somewhere a LWer is wishing they had made use of my archiving system so they could pull a particular page out of their local cache and upload it to Dropbox? Then we'd better hurry!"

The thing is that people aren't perfect rationalists, and part of being a good rationalist is acknowledging your own flaws and limitations. If you accept to kill, you'll kill, even in situations where killing wasn't necessary, because you'll stop searching the hypothesis space when you find a solution that involves killing. Or because you'll estimate that killing one will save two, but your estimation was flawed - you killed one, and yet the two still die. And it's also something you should know about the way humans work, that once you did something once, it's easier to do it again - and the killing curse seems to model that quite well. Harry putting himself a "I'll not kill" rule is him forcing himself to find solutions that don't require killing. Especially when you see how his "dark side" work, finding solutions to "impossible" problems when really pressured to do it, it doesn't seem irrational from him to test the hypothesis that he, with his rationalist training, and his "dark side" creativity, can find solutions that don't involve killing. And that only if that hypothesis is falsified, he'll resort to killing.
I think Harry's mistake is that he has left himself no setting between, "no killing" and "all bets are off".
I get the impression that the phoenix is a rewrite prompted by someone pointing out to Eliezer that in terms of consequentialism abandoning that woman was the same as letting an innocent bystander catch a curse, so Harry had already violated the new vow he was taking.
8Eliezer Yudkowsky11y
The title of the arc is "Taboo Tradeoffs". The phoenix was the original intended ending. I just couldn't get it written in time.
Aand, maybe you didn't want to face the wrath that would no doubt have risen with such a heart wrenching cliffhanger. ;-)
Not really - she could be rescued, while a dead person cannot be.
Yeah - it's not so much the downer, that's fine, it's that I miss Harry's resolution. Hopefully that pops up later.
1Eliezer Yudkowsky11y
Probably not - there's just no room for anywhere to put it!
I think you did, though it's not exactly the same decision. In this version, Harry didn't even wait for a bystander to die. He deliberately sacrificed Azkaban prisoners, some of which are innocent, in the name of higher probability of success. The decision is not very explicit, but he had decided to stop playing nice right away.
Or verifying a deal he made with Voldemort, though that might not make as much sense with Snape's character.
What, as in he made a deal not to hurt Lily, but killing's okay? Snape's messed-up, but I don't think he's quite inhuman enough to treat that as a deal honoured. The earlier part of the events, perhaps, but not the "Lily died without pain, then?".
I read it as Snape being happy that Voldemort offered Lily an out: his deal with Voldemort must have been "please let Lily live and I'll do anything". The memory confirms the story that Voldemort gave Lily an option out ("stand aside"). So he considers Voldemort to have held up his side of the bargain. This interpretation does not bode well for the Dumbledore-Snape alliance (which already seemed to be in bad shape in MoR)
That's how I read it as well. Snape saw that Voldemort had kept his word, and only killed Lily when she attacked him first. It seemed to me that Harry hadn't learned his lesson about his talks with Snape. He even noted that Snape's allegiance was wavering, and yet he shows him that Voldie given Lily her chance.
Harry didn't learn, no. But is that an advantage or a disadvantage? To go back to Chapter 76: Now, yes, this separates Snape from Dumbledore. But Dumbledore is not the protagonist. Harry is the protagonist. And what Snape can learn from Harry's actions are: Harry Potter will tell him the truth; Snape can trust Harry Potter. -or- Harry Potter is a brilliant plotter; so good that even at age eleven he outclasses both Voldemort and Dumbledore with his ability to fake being honest and trustworthy. If the first is true, Snape can put his trust in Harry, where he cannot trust Voldemort or Dumbledore. In a world where the prophecy clearly declares Harry Potter a power that ranks with Voldemort, isn't the obvious power to align oneself with the one who you can trust? When looking at the future, do you want it dominated by someone who let you wallow in foolishness and pain for their own advantage, or someone who treated you as you would wish to be treated? (Well, it might just mean the boy doesn't have enough guile to win, of course, but that suggests merely not burning your bridges. You're already in the other camp, after all . . .) If the second is true, the only sensible course is to make oneself as useful to Harry as possible, because Harry is unstoppable.
Who were Snape's two mentors? I used to think they were Voldemort and Dumbledore, in that order. But from the new chapter we learn that Snape only became a Death Eater when he told the prophecy to Voldemort, and that must have been immediately before Voldemort died or vanished. That doesn't seem to leave enough time for Voldemort to be a mentor to Snape.
4Eliezer Yudkowsky11y
Note that the prophecy is from before Harry was born, and his parents died when he was over a year old.
The timetable is getting tight for Voldemort to mentor Snape significantly, but I really don't see who else it could be; especially since it doesn't sound to me like it's supposed to be a huge mystery who the second mentor was. (I think we can exclude Quirrel/Monroe entirely.)
I like this as a hint as to where Snape might move next. His detachment from Dumbledore makes him a free agent in my book, unless he's more beholden to Lucius than I know.
Right, Chapter 76 was mainly to verify that Harry was trustworthy.
He gave her a slight chance of living with the guilt of having scarified her son, which sounds more like torture than generosity to me. If he really wanted to let Lily live, he would have stunned her, or he would moved to cast the Killing Curse on the crib without harming her. Asking her to voluntarily stop protecting her child is sadism, not a real attempt at sparring her life.
That's true enough. But I don't think keeping his deal with Snape required making sure that Lily lived, it required giving her a chance. You say it was a crappy chance. Maybe so. But this was a concession on Voldemort's part, and expecting a Dark Lord to do more than the letter of an agreement is asking a bit much.
Harry isn't much of a believer in the noble lie, if you haven't noticed.
He didn't even have to lie. All he had to do was say the thing in italics which he thought, right before the end. Snape if anyone understands exactly how excruciating emotional pain can be.
But after his previous encounter with Snape, where he offered Snape advice while not knowing what the advice was about, he seemed to accept that discretion can sometimes be the better part of valor, and maybe sometimes you should just shut up. He didn't need to be sharing these facts with Snape, he even recognized in the moment the undesirability of doing so, and yet he spilled the beans regardless. That boy just aint never gonna learn.
1Eliezer Yudkowsky11y
I would've liked to include the resolution too - but there simply wasn't room for that and the phoenix. I decided the plot could better survive the surgery of one than the other.

So I've got an alternate version that includes the important parts of both endings. Feel free to use or modify it if you like it.

The boy stood there on the rooftop, his own eyes locked with two points of fire. The stars might have had time to shift in their constellations while he stood there, agonizing over the decision...

...that wouldn't...


The boy's eyes flickered once to the stars above; and then he looked at the phoenix.

"No. Not yet," the boy said in a voice hardly audible. "I can do better. I can end death itself, not just Azkaban, if you give me the chance. If I can't stop death, if more have to die while I wait for the right time, then I will. But not yet. I still think I can win this without loss, and I won't...can't!...throw away that chance at a big victory later for a small one tonight."

Without word, without sound, a sphere of fire surrounded the bird's form, crackling and blazing with white and crimson veins as though it meant to consume that which lay within; and when the fire dispersed into grey smoke, no phoenix remained.

There was silence on the top of the Ravenclaw tower. The boy gradually lowered his hands from his ears, pausing only to wipe at his wet cheeks.

I figured it was for plot reasons. And upon rereading, it does make more sense - for some reason, I thought it was Fawkes that was coming, not another phoenix. My original reading was that Fawkes was somehow going to spitefully reject a chance to destroy Azkaban because Harry had missed his chance, which seemed absurd - knowing that Harry was giving up his chance at a phoenix of his own, and not his mission, annoys me much less. I'm still not sure if I like the new 85 more than the old, but it's closer now. Also, I'm probably being optimistic about how easy the writing of it would be, but my first impression is that it should be possible to make a version of it where Harry's resolution is the rejection.

One thing I really liked about this update is it helps explain why Harry hasn't figured out Quirrell = Voldemort yet. He's reasoning (perhaps without even having spelled it out in his head this way) that if Quirrell had been Voldemort, he would have won very quickly.

This is all fascinating, because it's a fairly good solution to the problem of "if Harry is so smart, why hasn't he figured out the solution to the problem that most of the audience has figured out by now?" I can't say I would have come up with that good of a solution to such a problem in any story I was writing.

That said, it seems like there are at least three conversations which could unravel the whole thing:

  1. Harry learns enough about horcruxes to make the Pioneer Plaque connection.

  2. Harry confesses about Azkaban, Dumbledore says "Harry, you fool!" and that's that.

  3. Hermione tells Harry about her recent conversation with Quirrell, confirming David Monroe = Quirrell = the plotter and suggesting the possibility that Voldemort was toying with Magical Britain for the fun of it during the war.

"if Harry is so smart, why hasn't he figured out the solution to the problem that most of the audience has figured out by now?"

Please remember that the audience has a lot more information on the subject than Harry himself, for not only do we get to see whats happening in the scenes of the story without Harry in them, we also have the huge advantage of having read the canon Harry Potter books. As Quirrell worked for Voldemort in canon, our prior probability that Quirrell is working for Voldemort is high, even before we read HPMOR. Harry on the other hand, hasn't even had a reason to consider that this is a possibility, let alone to assign a high probability to it.

1- Harry could conclude Quirrell made the Pioneer Plaque into a horcrux without coming to the conclusion that he's Voldemort. That Quirrell has made at least one horcrux is evidence towards him being Voldemort, but not all people who've made horcruxes are Voldemort.

2- This would probably convince Dumbledore that Quirrell is the top candidate for being Voldemort, but I think Dumbledore would need to follow it up with more investigation to convince Harry; I don't think Dumbledore has much more evidence to bring to the table if Harry lets this spill that he hasn't told Harry already.

3- Suspecting Quirrell as the plotter hasn't led Harry to suspect Quirrell as Voldemort yet, and I don't really see how hearing David Monroe's explanation of his backstory would lead Harry to conclude he was toying with Magical Britain for fun; he could simply conclude he's a largely amoral person who tried being good for the reward, but concluded that it wasn't rewarding.

Well, there is a thing that should at least ring a bell in Harry's mind to me. The "resonance" between Quirrell and Harry preventing their magic to interact which each other, when Voldemort transferred part of his magic to Harry, should be considered significant evidence towards Quirrell being Voldemort. Harry knows his magic partly comes from Voldemort, he knows Quirrell and his magic resonate in an unheard of way, and yet, he doesn't at least suspect a link between the two ?
I don't see the obvious link between those; magical transference seems like it could more easily lead to casting spells together more effectively, not it being a terrible idea to cast spells together. Harry is also biased against presuming causal factors that he can't articulate a motivation for, and so it doesn't seem likely that the character would come across that hypothesis in the first place.
I've read all the chapters up to 86 and I didn't figure it out. Care to enlighten me? Of course Quirrell is extremely suspicious but his persona can be explained as well by being Monroe.
If you need more evidence, vg'f rkcyvpvgyl zragvbarq va rneyl Nhgube'f Abgrf obgu gung Dhveeryy vf Ibyqrzbeg naq gung Ryvrmre jnf trahvaryl fhecevfrq ng ubj ybat vg gbbx crbcyr gb trg guvf. Punyx vg hc gb n pbzovangvba bs crbcyr orvat hasnzvyvne jvgu pnaba, crbcyr nffhzvat Ryvrmre jnf gevpxvat gurz, naq vyyhfvba bs genafcnerapl...
I think part of the issue is that Eliezer decided to portray being a good manipulator realistically with the result that Quirrell successfully managed to manipulate half the audience.
This is spoilers, which Eliezer officially retracted. Please rot13 it, at least.
Have you ever read Philosopher's Stone? I hadn't when I first read HPMOR, so I totally missed the Quirrell thing, but it's pretty blatant once you're handed the answer on a canonical platter.
I didn't read the canon.
Then a first-book spoiler for you: Ibyqrzbeg fcraqf svefg lrne rzorqqrq va gur onpx bs Dhveeryy'f urnq.
Should I read your comment or will it spoil the fun? I'm assuming that it is possible to read and understand HPMOR without having to read the canon? So far I'm doing fine. Although I also watched the last HP movie so I have some info from the canon.
If you've read HPMOR and watched Deathly Hallows, it will not be much of a surprise. However, it has not been explicitly stated by any of the material you've read/watched to date, so it is technically a spoiler. That said, HPMOR does get better when you start getting all the canon in-jokes, so I would recommend consuming the originals at some point. They're actually pretty good(even if the first two are basically kid's novels).
There's a big fat hint in chapter 20. It's compatible with Monroe!Quirrell being an unpleasant person in the same way Voldemort was, but one of those on each side including the supposedly good one is less likely than the big bad playing both sides.
Here are the relevant quotes: [...]
Well, he pretty clearly turned the Pioneer Plaque into a Horcrux, told Harry, then Obliviated him when he reacted badly. Also, at two separate points he claims to have "resolved his family issues" and later states that his family is "long since dead by the Dark Lord's hand." Hardly conclusive, but there are other, similar little hints and Q has after all admitted to "playing a game of lying with truths." Oh, and Voldemort in Canon always wanted to teach at Hogwarts. So there's that.

You're not supposed to say what he did to the Pioneer plaque out loud! It's more funner to realize it on your own.

Where do you get that he Obliviated Harry? All of his lines sound like reasonable first-iteration attempts, and Harry didn't lose time.

I, ah, I got it from the ellipses. Which is suddenly seeming much less reasonable. In my defense, it IS the same effect used for Hermione.
Quirrell can't cast spells on Harry without some sort of magical resonance occurring. He almost certainly has not been obliviating Harry.
Well, it's the same effect as when H&C brute-forced Hermione. Although that's a good point about their magic; I'd forgotten about that. There are ways around it, of course ...
Do you know which chapter that was? I cannot remember this passage.
Chapter 20. Of course, that's just my reading of it, but I think it's a popular interpretation - it certainly seems the most plausible one.
That is so weird - I've never heard that interpretation, and I can't seem to get it out of the text. I just see Harry reacting not-badly, and no sign that Harry was obliviated.

The, ah, the ellipses?

"I subscribe to a Muggle bulletin which keeps me informed of progress on space travel. I didn't hear about Pioneer 10 until they reported its launch. But when I discovered that Pioneer 11 would also be leaving the Solar System forever," Professor Quirrell said, his grin the widest that Harry had yet seen from him, "I snuck into NASA, I did, and I cast a lovely little spell on that lovely golden plaque which will make it last a lot longer than it otherwise would."




"Yes," Professor Quirrell said, who now seemed to be standing around fifty feet taller, "I thought that was how you might react."




"Mr. Potter?"

"...I can't think of anything to say."

"'You win' seems appropriate," said Professor Quirrell.

"You win," Harry said immediately.

"See?" said Professor Quirrell. "We can only imagine what giant heap of trouble you would have gotten into if you had been unable to say that."

They both laughed.

Waitaminute. That was just him staring silently, wasn't it? And the line about "fifty feet taller" just meant he seemed so much more imposing for hav... (read more)

CFAR could make very good use of a lot more money than this while starting up. I don’t work for the Center for Applied Rationality and they don’t pay me, but their work is sufficiently important that the Singularity Institute (which does pay me) has allowed me to offer to work on Methods full-time until the story is finished if HPMOR readers donate a total of $1M to CFAR.

That's quite the author's advance!


Speaking of which, isn't there anyone with CFAR-authority that wants to make a fundraising announcement post, as Luke did for SI?

I was curious about that as well. I suspect they have decided to wait until SI's fundraising drive is finished, for behavioral economic reasons as well as their prioritization, but it passes up the option to determine LWers' relative preferences for SI and CFAR.
Well, they mentioned in the SI fundraising post that there would be a CFAR fundraiser, and that's why I didn't donate to SI.

HP: Punch AM in snout to establish superiority.

Anyone else getting tired of this? Harry does it to everyone he meets, including Minerva and Hermione.

Everyone else: presume HP is inferior; withhold information.

I can see both sides of it.

Yeah, that's the other side of the same complaint :-) I'm not complaining about Harry's behavior, but about Eliezer putting so much macho posturing (and opportunities for it) into the story.

Well, the premise of the story necessitates that Harry be an eleven year old boy and that he be highly competent. Having people constantly underestimate him is a practically unavoidable consequence.

Harry could just quietly, secretly exceed people's expectations, but when those people are his allies, it's probably a poor strategic decision.

It's okay, he's just rewriting Ender's Game.
There is a little too much of that for my taste. There are plenty of other things going on as well in the story, enough of them to keep me interested, but the bits that seem to be just Ender's Game don't impress me. Being smart isn't nearly that reliable at producing victory in battle; there are too many details of execution that matter tremendously, and there's just generally too much unpredictable stuff going on. Admittedly, there have been historical generals who consistently won, but they always had some consistent edge that for some reason their enemies couldn't fully duplicate or counter (higher technology being an obvious possibility, or perhaps ability to recruit soldiers from a population that already possessed useful, difficult to develop military skills not practiced elsewhere).

Harry hasn't won consistently. He's lost plenty of mock battles, and while he sometimes gets his way against adults, he's sometimes thwarted. Harry also does have a couple advantages that can't readily be replicated by other characters, namely his technological and scientific savvy, and the True Invisibility Cloak, and the time turner which can't be replicated by most of his opponents.

Eliezer wrote ages ago that he gets people complaining that Harry wins too often and isn't sufficiently challenged, and people complaining that he loses too often and doesn't accomplish much, and considers himself to be doing his job properly if he's at least getting similar amounts of each kind of complaint.

He admits freely that Moody would have kicked his ass in a real fight, so I'm not sure how much actual superiority was established there.

Just because Harry's learned to keep his claws sheathed doesn't mean he's not still engaging in dominance contests.

I think in this case it's more an "I'm not as pathetic as you think I am" contest. Nobody's going to mistake him for the best duelist in that group, but he's not willing to concede complete inferiority. It's certainly a status game, it just doesn't rise to the level of "establish[ing] superiority".

Moody set it as a condition for being able to speak as an equal.
He gets the mechanism wrong though. In a real fight, Moody kills him or at the very least takes his toys away if he's needed alive. There wouldn't be any time-turned copies of him in the first place.
Stable time loops are sort of a problem for what-if scenarios - it's sufficiently hard to make up one, coming up with alternates isn't always possible.

I bet a large portion of the readership would have been disappointed if that didn't happen.

And in this particular case, that was the only fast way for Alastor to gain enough respect for Harry's competence that they could cooperate in the future. It wouldn't have been consistent with his already established paranoia if he just believed Dumbledore & co.

I can imagine this getting old eventually, but imo it hasn't happened yet.

Yes, but its fun to watch.
It happens a lot, but you wouldn't expect it to happen only a LITTLE with a super intelligent 11 year old.

Harry needs to think more before he tells people things just because they ask. Just because somebody's not Quirrell, Harry, doesn't mean that their knowledge has no consequences!

Holy shamoly, I got name-dropped in the notes.

Now I've got even more incentive to blast apart my current writer's block on "Myou've".


To add to you incentive I'll donate £10 to the Against Malaria Foundation when you do (utilitarian blackmail?).

gasp You can have a writer's block?
Hey, I had a pretty good run of near-daily, 2k-word chapters. At the moment - the first non-Myou've story I tried breaking the block with foundered and is probably defunct. However, I'm currently working on another non-Myou've story; and am actually making progress. I've got a skeleton of a plot written out, and over 1500 words of an actual first draft, and am getting feedback and encouragement by writing it in a GoogleDoc I've given a few other people access to. I think I've got a good chance of actually turning this one into a complete story - and once I do, I'm going to try using the momentum I build up by getting back to "Myou've".
High five!

Voldie isn't like any other Legilimens in recorded history. He doesn't need to look you in the eyes, and if your shields are that rusty he'd creep in so softly you'd never notice a thing.

Harry and Quirrell spend a lot of time together, and now we learn that he might not even have to look Harry in the eyes. How much of Harry's brain has Quirrell already mapped out? Perhaps this is why he is always playing "one level above you". Maybe this is why Harry doesn't notice some things he otherwise might.

I'm going to start reading all their conversations assuming that Quirrell can read all of Harry's thoughts in real time the same way we can, and interpret all his statements in light of that. Could be interesting.

They can't interact magically, so no.

This is in fact a major literary reason for the above. :)

In canon, Voldemort has extra "legilimency" style power to know harry's thoughts and influence him due to the scar, even though their connection makes it dangerous for the two to touch (at least while he was in Quirrel). Obviously this isn't great evidence, but I think it's relevant.
Signs of leglimency can be detected, so if Quirrell is leglimizing Harry, he may be risking getting caught. The fact that Harry has an occlumency teacher who uses leglimency on him in an instructional setting might serve to disguise other people using leglimency on him though. We don't know what kind of evidence checking for leglimency can provide about recency and whether the mind has been accessed by different people. However, I doubt that Quirrell has been using leglimency on Harry, because there's a point where you're really just giving the antagonist too great an advantage, and if Quirrell has been accessing the contents of Harry's mind undetected, I would have an incredibly hard time buying the protagonists not being completely fucked (tvtropes link.)
There is some time resolution.
upvoted for tvtropes warning.
I suspect that Voldemort's legilimency though occlumency barriers may have been the same sort as Quirrell's in Ch. 49.
Oh, you mean a bluff using knowledge gained by other means? That's an interesting thought. Quirrell does do that a lot when we know he couldn't be using Legilimency, doesn't he?
He also had this ability before Harry ever started learning occlumency so it would be possible for him to sneak past if anyone could.
At one point the Defense Professor does give a plausible reason why he might have resolved not to use Legilimency. From Chapter 74:

Heh. Just noticed the explicit comparison of Moody to Rorschach.

This really confused me until I realised you were referring to a comic book character, not a famous psychiatrist.

Gerald Grice. He was the first person Rorschach killed, and triggered his change. He killed Blair Roche, 6 year old girl, and fed her to his dogs. Both are named dropped by Moody as he discusses the Killing Curse.

Oh, cool. I didn't get that.

A reminder: there's an extensive Reddit discussion (>288)

My thoughts: 1) It's becoming increasingly clear that - even though Harry has accumulated a wealth of knowledge and evidence by this point about Dumbledore, Quirrell, Lucius and Snape - he still knows little about Voldemort (e.g. motives, background, abilities, weaknesses). I am fairly confident that this is intentional on the author's part; withholding Harry's (and the reader's) knowledge about Voldemort is an excellent way to ensure that a Revelation of information occurs within the next few chapters about Voldemort's background. 2) We haven't yet seen Harry's reaction to the fact that Flitwick invented a Charm; presumably he will update his model of the nature of magic when he has time to process this. 3) The joke at the beginning of the chapter making fun of America's disconnect with the rest of the world was particularly brilliant and appreciated

Minerva already told him that people invent new spells all the time early in the story.
Without knowing the details of the process of researching new Charms, we can't really differentiate between "invented", "discovered", "created", and "learned". Flitwick is not a scientist and I don't trust him to report the difference correctly. The discovery itself is not on-screen.

I found a review on ff.net that probably echoes with many others who are not as immersed in LW culture and even those that are. I thought a discussion of this person's points would be constructive so I've copied the review here: " So.

I have a few problems with this.

First of all, the use of terms and situations that the readers don't understand. In earlier chapters, you would do this, and then you would EXPLAIN the reference. That was something I liked. It was educational. Now, however, you're simply calling on references and expecting the audience to understand. I get that it would be irritating to have to explain everything, but it gets to a point where your fanfiction gets mixed up with your essays. And that's not good, because the result of this mixture fails to do the job of either a fanfiction OR an essay. Remember, the people who read this are unlikely to be previously familiarized with such sources.

Now, I don't think you're doing this on purpose, but to a reader who doesn't BREATHE the terms you use because they aren't in your field, it seems as though the only reason you include these are to make Harry seem smart. To you, it may seem natural for Harry to use such sour... (read more)

That "science forbids" statement is not great. I can dismiss lots of arguments in the name of countering privileging the hypothesis. I shouldn't need to argue against them specifically unless they were brought to my attention for good reasons. That's why I dismiss cranks who claim they've proven the Riemann hypothesis without reading through their proofs to find out where the error is. The mechanism that generates these proofs isn't correlated with mathematical truth, and the space of possible proofs is large.
You're missing the point that reader objections you can find a way to dismiss as irrational are still reader objections. HP:MOR is explicitly intended as propaganda; so irrational reader objections are particularly important.
I'm not dismissing the objection. It's a perfectly sensible objection. I am dismissing the statement I pointed out and only that statement. Perhaps I should have made that clearer.

What percentage of "facts" Moody exposits to the audience/Harry do we think are false or misdirection? At the least, the comment about Avada needing to find a soul is out of line with Canon where it can be blocked by inanimate objects such as statues.

Also: I look forward to the inevitable Moody/Quirrel showdown/makeouts.

My guess is that this was a deliberate change. I always thought "cannot be blocked, except by inanimate objects!" was kinda lame.

Suddenly Quirrell's using it in the duel with Bahry is looking a lot weirder. What happens when he dodges it, does it go straight through the wall and keep on going indefinitely until it hits someone? Isn't that a massive liability since he risks someone seeing it, thereby giving away his presence?

Being able to be blocked by inanimate objects might seem "lame" for an epic forbidden spell, but being able to pass through solid matter like a jet of neutrinos turns it into yet another game-breakingly borkable element like the Bag of Holding. Combined with the Eye of Vance, Moody should mostly be able to avoid dueling in favor of sniping dark wizards through buildings.

This seems like an uncharacteristic failure by EY to think things through.

Maybe it hits a Dementor and that's how they reproduce.

Moody would have to take into account the coriolis non-force, at least for very-long-range shots. How fast does a killing curse move? Also, to what amount is a curse affected by curved space? Do they react to gravity at all?

It's not clear what it would mean to not be affected by curved space or gravity, since there's no "straight" besides geodesics and no "non-accelerating" besides freefall, but that doesn't seem to stop much in the HP verse.

Speaking of curved space, I've noticed that there are spells to make things bigger on the inside. If you do this just right, you can create a singularity known as a cone point that ought to send any spell fired at it back in the direction of the caster. Also, you could make a faster-than-light drive, which could be used as a time machine.

If the inertial mass of a spell is greater than its gravitational mass, it would appear that the spell doesn't react to gravity as much as it should. It is also possible that spells work a bit like brooms.
Gravity doesn't work that way. Something not reacting to gravity under general relativity is like something stopping under special relativity (or even Galilean invariance). However, considering that there's a spell that does just that, this doesn't mean much.

I hereby declare Arresto Momentum to match the velocity of a small mass to the velocity of some much larger mass that the wizard thinks is a reference frame.

Does that mean Harry can't use it (becuse there is no universal reference frame) or he can use it in all sorts of munchkiny ways (I stop the car ... relative to the moon!)

4Eliezer Yudkowsky11y
Well, for one thing, he's not powerful enough to cast it period, but if he were, I expect it would only work on near / nearest masses.
That requires original research, like partial transfiguration.
That's what I had in mind, yes.
Original research is dangerous. This original research in particular seems dangerous.
Now I come to think, he would probably just conclude it uses Earth as a reference frame, just as broomsticks use Aristotelian physics and transfiguration uses form/substance duality.
You can't use Arresto Momentum for that; you need a much more massive object as a reference, but your reference frame only contains massless objects. I guess you could say that massless objects have much larger mass than other massless objects, and use Arresto Momentum to make photons go in arbitrary directions with negligible losses. If you can make a surface cast a long-lasting Arresto Momentum, you have a near-perfect mirror for all wavelengths from radio to gamma and all angles. That would be useful. (Of course you can also make the light slower if you wish, but the fun you can have with arbitrary refractive indices with no wavelength dependence and no absorption is redundant here.) Also, if we figure out the necessary ratio of masses at given magical energy, we can use the spell to measure mass. Assuming your aim is precise enough to Arresto Momentum a neutrino, anyway.
So what would it do with a wizard who had truly internalized the principle of relativity, and who understood that there was no privileged reference frame? Could he use it to de facto impart an arbitrary velocity to an arbitrary object?
You can equalize velocity of a given small object with that of the caster's reference frame. The excess momentum is transferred to the Earth (or potentially another massive body, though there is no proof that magic works outside the Earth's atmosphere, which incidentally means that the Pioneercrux may have decayed). This way there is no preferred reference frame.
Of course there's no proof, but I don't think it's really possible, if only for literary reasons, that the Sphere of Stars spell is just a fancy hologram. I think we can take that as fairly strong evidence it's working as intended.
What is it then? A signal sent from the pioneer horcrux?
So "arbitrary" might be a bit strong, but what's to prevent him from using the Moon or the Sun as a reference frame? Or even the Earth as a whole, instead of the local part? Even imparting a relative 1000 mph to an object near the equator would be pretty powerful.
"the caster's rest frame" is relativistically invariant.
But he didn't say "the caster's reference frame", he said "some much larger mass that the wizard thinks is a reference frame".
Just saying that if the spell is designed to work relative to the rest frame, then no amount of relativistic internalizing will change how it works. Of course it is possible in the HPMOR universe to design new spells, and a competent Wizard with a good grasp of invariance in physics might be able to create a new spell, Attache Momentum.
And I'm just saying, the way Eliezer phrased it above, there's no singular reference frame - any suitable mass will do.
You are right, he did phrase it this way, which makes this spell unreasonably easy to munchkin. He would have probably thought harder about it were he a DM of an actual DD game.
It seems like a hack of the rules on the level of partial transfiguration. Also, if you house-rule that it requires "magical energy" in proportion to the delta-momentum, it shouldn't be too overpowered.
Magic works like the author of the story wants it to work.
I think it's safe to say that the HPMOR universe still runs on some sort of rules, even if they're not the usual ones Einstein taught us.
Actually, Eliezer has stated that he deliberately inserts impossible details in all his stories because he's disturbed by the notion that they might be simulated somewhere. I wouldn't expect it to affect the plot, though.
Didn't he say that he mentioned the time-turner because it disproves the simulation hypothesis? It would also guarantee that nobody would simulate it. He seems to have figured out how to simulate it later, but that requires simulating everything, and there's no guarantee that there will even be a reality with a stable time loop, unless you have the infinite number of realities necessary to allow connectedness, in which case you can't possibly simulate all the possibilities.
Actually, there is a guarantee that there will be a stable time loop. Look up the Novicov Consistency Principal some time. And I think that was to stop people speculating that magic was being provided by the Matrix Lords, although sadly it doesn't. I was referring to the corridor tiled with pentagons (although it never actually says they were regular pentagons) and the spiral staircase that lifts you by rotating.
The Novicov Consistency Principal relies on the Kakutani fixed-point theorem, which relies on convexness, which implies connectedness, which implies an infinite number of realities.
It does not.
I admit I've never seen a proof of the Novikov Consistency Principle. I know that's how I'd prove something like that, and I know I could easily come up with a case of time travel with no possible stable time loop of I'm given a discrete space, a non-compact space, etc. What does it rely on?
Solely on the uniqueness of the metric in GR.
Do you have a link to a better explanation? Also, can you explain how this could be used to find a stable time loop?
Sorry, I cannot find a link, but feel free to ask what does not make sense. As for the stable time loop, I'm not sure that it is always possible to find, given that you apparently want to fix both initial and final conditions of a hyperbolic PDE, unless I misunderstand what is involved in constructing such a loop.
Couldn't it be approximated?
The theorem doesn't tell you how to find a fixed point. It only tells you that one exists.
But if you had done such arduous research as, say, reading the Wikipedia page for the NCP, you would see that a sum over histories using only non-paradoxical timelines apparently works. Not that I really understand that in more than a superficial way, but it sure as hell sounds like an answer to your point.
There are only guaranteed to be non-paradoxical timelines if you have an infinite number of realities, which is what I was saying from the beginning. You could look for all the timelines that are within delta of being a paradox. I think the shadowing theorem guarantees that, for small enough delta, this is epsilon-close to a non-paradoxical history. I don't think it tells you what delta is, and I don't think it's guaranteed that every non-paradoxical history will be shadowed. This would mean that you're not randomly picking the choice of history. More importantly, it might be that none of the non-paradoxical histories are shadowed, and you'll have no idea what to look at.
Do random samples until you find enough, then. It wouldn't be perfect, but it should be close enough that you wouldn't notice with enough computing power, right?
I can think of ways to simulate those quite easily. It does involve cheating with the environment, but not really cheating with any minds. Mostly the same kinds of tricks mentioned in Eliezers "that'd it take to make me belive 2+2=3" article. Like, for example, deforming the tiling pattern constantly so that it was always the right type of angles and side lengths where the eyes were looking, and stopping the motion detection from going of on those changes. Or have the stairs tile exactly, just snap people on them up in exact increments of tiles, and again doing clever things with the way motion is detected in the eye.
The pentagons are doable, if you're willing to cheat, but the spiral staircase is harder; spiral staircases appear to lift things but actually don't. What would an optical illusion that was true be like? How do you build Penrose steps in 3d?
Inception sort of almost pulled it of.
Nah, that scene only works from the right angle.
Probably, but these are not mutually exclusive. If Dumbledore is right, the set of rules that the HPMOR world runs on are the laws of Narrative Causality.
You know that spell was invented for the film, right?
According to the wiki: It looks to me like they established that there is a spell that does that, but it wasn't named until the movie. I suppose without the name there's no real evidence that it doesn't just accelerate the subject in any way the caster pleases. In any case, in the MoR verse, the brooms act in a manner that involves some sort of rest state. Also, as of Eliezer's reply to this post, that spell canonically exists in the MoR verse.
Well, it's the name that actually tells us it's "arresting momentum" and not, I don't know, stopping him getting too close to the ground or some sort of anti-gravity spell. The scene is in the book, but the spell itself is not. (The wiki treats the films a canon when they don't actually contradict the books, instead of a separate canon like most sane people would. They do the same for everything, in fact, from videogames to trading cards, although they draw the line at fanfiction.)
"Making things bigger on the inside" does not equal "bending space into any damn shape we please."
A cone point only requires being able to make things bigger on the inside. Just make a series of concentric spheres that are the right amount bigger on the inside and outside. If you don't make it smooth, it won't be perfect, but it just has to be good enough. I don't know much about the faster-than-light stuff. From what I can find, an Alcubierre drive needs at least some negative mass, which, from what I understand, would translate to having to make things smaller on the inside. It seems likely that wizards would be able to make things smaller on the inside too, and they just don't do it much because it's pretty useless, at least for things wizards would think of.
Good point on the spheres, although I think Extension Charms are tied to enclosed spaces (hell, they might not even bend space. They could tap into another dimension or move you "out of phase" or something.) Regarding the FTL, Alcubierre drives need a ring (or donut in the latest designs) of negative energy (or matter, I guess.) I can see that translating into "smaller on the inside" constructions, although I doubt there's actually a spell for that (although you never know.) Might be able to transfigure the stuff, though.
Perhaps that's just because no wizard is well-versed in non-euclidean geometry well-enough to understand how it would work in a non-enclosed space. Besides, enclosed is relative. Maybe light doesn't travel through it, but neutrinos and your enemy's spells do. It doesn't matter. As long as it takes longer to travel through, it works. For example, you could use different kinds of glass to make retroflectors using the same principle, since light will travel at different speeds. Perhaps the same spell works. If the same spell could make something two or three times bigger on the inside, then why not one half times bigger?
What happens if you make it bigger on the inside and then turn it inside out?
Could be. Hard to tell without the author telling us. I think most spells are disrupted by solid objects. And most offensive spells would risk destroying whatever you charmed. Would be interesting to try it on something made of glass, though. Oh, I see. Cool. I assumed they were purely theoretical. Interesting point. I doubt it works by specifying the increase as a number, though. Hmm, there are probably other uses for containers with shrunken insides.
Inflatable mattresses (or waterbeds) that can be filled quickly/efficiently. If rooms can be enchanted in this way (houses can certainly be bigger on the inside) then enchanting a long hallway in this way would allow people to walk longer distances in a short amount of time. If the container is transparent, it could be used as a magnifying glass for things you placed inside.
Wizards already have shrinking charms for the first one, but well done.
In a sense they are. I've never seen anything about anybody actually doing that. I just know it would work in theory. Lenses and optic fibers and such work on the same principle, but they aren't cone points.
"When" he dodges it? This seems like strong evidence that Q knew he wouldn't. An interesting point. Do we know that he doesn't, in cases where he wants them dead as an end in itself?
I'd be surprised if Quirrell isn't competent enough to be able to judge effectively if his opponent is going to be able to dodge his attack, and Bahry thought he was going to be able to dodge it. Killing a guard would be a bad idea (if he's still alive he can be obliviated without blowing a hole in their security,) so if the spell travels through walls it seems like a dumb move whether it hits or not. We don't know for a fact that Moody doesn't snipe dark wizards through buildings, but if he did I'd think it would have been mentioned even with the small amount of stage time Moody's had so far.
Could be that the bolt just doesn't move that fast. If it's possible to dodge at close range (like Bahry?) then it would have to move fairly slow.
Well, we don't know just how close they were, but if it were all that slow people wouldn't even bother using it in combat. I tend to assume that fired spells are somewhere in the ballpark of fastball speed. A spell that can be dodged with difficulty when fired by an opponent you're dueling should be more than a little more difficult to dodge if it comes without warning out of a wall behind you though.
Perhaps it has a range limit.
It would have to be significantly shorter than a lot of other spells have been shown to be (able to engage in ground-to-air combat against brooms) to be unable to target a person inside a building from outside it, or for a very large building like the castle of Hogwarts, at least from several rooms away. Ordinary sniping relies on large amounts of distance between the shooter and the target to prevent them from being noticed and avoided or attacked. Moody could just rely on having multiple walls between him and his target.
Seems pretty obvious that a Killing Curse can't hit anyone but the intended target. You don't want dead that bystander you're not thinking about. Also "I meant to kill someone else" would be a defense if arrested for it. Given that, it can fade quickly once it's moved past the target.
Hardly obvious to me. Just the mood is required to cast it, the "small crack" at the soul. A killing beam is then launched. The beam keeps going until it reaches a killable target, which it very clearly is then implied to kill. I always find it strange when people are reading so many implications that clearly aren't there, and are denying the implications that are...

I always find it strange when people are reading so many implications that clearly aren't there, and are denying the implications that are...

No doubt they feel the same way.

I don't remember anything about the spell not being able to hit anything but the intended target, either in canon or the MoRverse. What's your source? Or, if there is no explicit source, what makes it "obvious"?
I just said. "You have to mean it", so it's odd that you could kill someone you didn't mean to. Even if you interpret it as "You have to want someone dead, not necessarily the same person", "if you're arrested for killing with it, there's no possible defense", and "I meant to kill the Death Eater, but I hit the bystander" is a possible defense. Also nobody ever mentioned collateral damage.
Wanting to kill a specific person may be a requirement for fueling the spell, sure, but I don't see why that necessarily entails everyone else being immune to what is essentially a profoundly lethal effect. Once a bullet is in the air, it doesn't matter what motivated the firing of the gun. The bit about nobody mentioning collateral damage sounds like an argument from silence. I'll tentatively grant you the point about "no possible defense", but to me it seems like Moody could well have been talking about deliberate, cold-blooded murder rather than all possible circumstances. I mean, by the time of the "no possible defense" line he's already name-dropped the Monroe Act, which is nothing if not a big, fat exception.
FWIW, "You have to want someone dead, not necessarily the same person" is essentially how "intent to kill" works in a legal sense. That is, the distinction between murder and manslaughter is whether, by your actions, you intended to kill someone; under the law, it doesn't matter whether the person actually killed was the person you intended to kill, or not. Not that the rules of magic are necessarily modeled after modern US jurisprudence, but it might be that they both reflect a deeper moral concept.
What happens if Alice Attacker tries to kill you, and you try to kill her in self-defense, but end up killing Bob Bystander? The Killing Curse solves that one by having self-defense not count as intent to kill; does law do the same?
I think so (it's been quite a few years since my brief foray into law school). Let me do some quick Googling... Yep, there it is: Looks like it may vary in different jurisdictions, but
Well if you were using it fighting Death Eaters under the Monroe Act, and accidentally killed a bystander, and had fellow aurors to back up your story, you probably wouldn't be arrested.
Well, in the original canon, Voldemort fires one at Dumbledore, and Fawkes catches it and is reduced to a chick (phoenixes being unkillable.) Of course, evidence from the original canon doesn't suggest it being able to pass through solid matter either, so that doesn't mean a whole lot with respect to HPMoR, but the spell would have to fade pretty damn quick to not be a liability for being spotted through a wall after missing. If it does it sounds like the best suggestion so far for resolving Quirrell's use of it in Azkaban, but that still leaves Moody able to snipe people through buildings.
So that's why Dumbledore set a chicken on fire - he was reviving Fawkes!
Sniper!Moody isn't a huge problem. Any halfway competent Dark wizard would plan for that kind of enemy (is the eye of Vance famous? anyway, anything that can help aim a Killing Curse through walls) and have wards in place to detect approaching and casting. It just makes walls transparent on both sides.
The Eye of Vance is well known enough that Moody was able to look it up and track it down, but not well known enough that he doesn't bother hiding facts such as its ability to see in a full sphere and through obstacles. If wards can be put in place to detect approach with that kind of precision (evidence, the Marauder's Map, but that sort of thing may be beyond modern wizards, as it's part of Hogwarts' defense system and there's no other evidence of location scrying magic,) then you get an Avada Kedavra stalemate between Moody and anyone ensconced in a sufficiently well protected stronghold, but a complete mismatch between them and any of the vast majority of people who can't see through walls. Considering that Moody was already a well known dark wizard hunter by the time he lost his eye, if the wielder can snipe people like this, it raises the question of how he got it from the person who had it in the first place. You'd expect a power hungry dark wizard to be able to use Avada Kedavra, and when you can actually see a full sphere around you through obstacles, it doesn't take a whole lot of creativity to notice that if you can use spells that go through obstacles, you can use it to attack people who can't see you.
For context, the original backstory: So, it cost the very experienced Moody a great deal, and that was him going all out ('silly rules'). I don't think we can rule out that the "powerful Dark Wizard" wasn't effectively employing the omniscience of the Eye.
Shooting someone with Avada Kedavra through a wall isn't going to result in the loss of any body parts though, and can be employed before face to face engagement is even an option, unless Moody had some way of teleporting straight into the wizard's stronghold, which would imply some pretty lousy security. If the Eye of Vance lets you AK people through buildings, I wouldn't think the added security of having it would be worth enough to Moody to overcome the risk of trying to acquire it, which would probably be phenomenal unless whoever had it before was an idiot.
It could be used to force other actions, per Quirrel's excuse to Harry, and the forced choices lead to limb loss.
It's much harder though, to dodge a bolt that comes straight out of a wall without any warning because you can't see the person who fired it, who if they have much sense has deliberately moved around so that they're not only attacking from a point where you can't see them or fire back, but from an angle where you won't see the beam either. All the best ways I can think of to take the magical eye from someone who can do that, and lives in a place without "silly rules" against actually doing it, wouldn't place me in a position to lose limbs in the encounter. If he's not as Constantly Vigilant as Moody, he might be poisoned, but assuming it wouldn't destroy the eye or render it unretrievable, I'd sooner call in an airstrike. Although it's chronologically too early for transfigured predator drones, which would be my top choice.
Maybe a dark ritual involving sacrificing a limb to blind someone or something?
Maybe, but I doubt it. Since every time a new magical element like this is posited, the obvious thing to do is ask how someone like Quirrell could abuse it, I'll note that Canon Voldemort was capable of instantly creating a better-than-new magical prosthetic for Peter Pettigrew after the latter sacrificed his hand for a ritual. Limb farming his own Death Eaters is thinking too small, particularly since the prosthetics might be identifiable. I'd go with "Imperius innocent civilians into casting the ritual for you and then memory charm them so they don't notice their limbs have been replaced." Although maybe you don't need to replace their arms, since even when they do find out, what are they going to do about it, really?
I know that this is quite old, but it bears mentioning that consent is often a huge issue with magic, for more or less precisely this reason. We also know that it is important in the Potterverse as well, since Pettigrew's line was: Not to mention: This shows that consent is important on both ends. Imperius could easily not count as actually giving consent.
Moody can still dodge.
That is not obvious at all, at least to me. Or Harry, who seemed to interpret it in terms of risk to bystanders.
So if you fire it at the ground, can you kill someone on the other side of the Earth? Not being blocked by inanimate objects is kinda lame too.

Don't worry, the power drops off with the inverse square of the distance. It's lethal at pretty much any reasonable range, but then drops off quickly after a half mile or so.

I just made that up.

Actually, it spreads as an Airy disc, which gives it a radius of about 300 metres at the far side of the planet, and the effect is divided among all the souls it hits. If you hit a city on the other side of the planet, you just take a couple days off everybody's life. (The technical term is "statistical homicide")

That would make sense as a general rule for spells, otherwise why do they bother having duels face-to-face rather than sniping from nearby mountains? (Or an invisible broomstick 2000m up..)
You do have to aim it by hand and eye. You try hitting a human-sized target from a moving platform at 2km.

Given the descriptions of wandwork we've seen in canon and in MoR so far, I imagine it'd be difficult to reliably hit anything person-sized past thirty feet or so. You can't sight down a wand if you have to swish and flick (though a wizard's staff with a telescopic scope mounted on it is a nice Discworldly image), so it should be about as accurate as throwing a ball -- which is to say not very.

We know of at least one spell that aims itself (Flitwick's) and area affect spells are possible (with a massive fireball it doesn't matter how you aim). Alternatively, take a potion of +10 accuracy or the equivalent.
Felix Felicis may be the only potion that performs that function, and it's sufficiently broken to be the Potion Not Appearing In This Fic.
Just find something that was made by using up a lot of accuracy. That should do it.
A target with nothing but bulls-eyes will do.
You would have to get extremely (un)lucky to do so. A human, lying down, takes up about 1 m^2 of space. Even if you fired it at a city with a population density of 10000 people/km^2, you'd still only have about a 1% chance of hitting someone (if you could even aim well enough to hit a city from 12000 km away).
This. If not this, Moody is lying, which is possible, as Moody is the type to keep information like that "in reserve", but I actually doubt that is the case, as sooner or later Harry would witness for himself a killing curse being cast, and would find that Moody had been lying.
Also, I doubt that everyone else in the room was either clueless or willing to let Harry receive such massively incorrect info.
Like an ordinary muggle missile, KC was designed with a built-in self-destruct mechanism, which is activated when its target is not hit. Thus you die if you block a curse aimed at someone else, but not if the curse misses the target and you happen to be in its path.
A killing curse hits a molecule of nitrgen. The molecule bursts. Yep, doesn't really make sense.

Moody/Quirrel showdown/makeouts

Moody♠Quirrell ... no, just no.

(Harry seems to have been through quadrant vacillation between Hermione and Draco, though. Hermione starts flushed for Harry, who doesn't reciprocate, so she goes pale instead to prevent him from becoming a Dark Lord. Harry♦Hermione seems pretty stable, although Harry has some pale infidelity with Draco — who briefly waxes caliginous before attempting to auspiticize between Harry and Lucius. After Draco drops Hermione, she tries to set up Harry♥Draco, not knowing that Draco has more ashen aspirations ....)

What do you mean, "no, just no"? Here are two extremely competent characters who will inevitably be pitted in full force against each other. They both respect competence in others (and likely relish a bit of a challenge), so they will necessarily admire each other, more and more as they get the measure of their respective power. They're not naive preteens drunk on their first slightly creative idea, they're adults with a lifetime of experience who know exactly how to have a rivalry. They'll never grow tired of playing against each other and they know that perfectly well. You will forgive me for shipping that just a little bit.

It's odd, being reminded that in the mainstream mentioning slash is on the level of potty humor, when in the world I normally inhabit you're supposed, on pain of being called a narrow-minded Philistine, to appreciate a story's literary value whether or not it's angsty porn in a setting based on dogs' social and reproductive habits where men get pregnant.

Eh? I've nothing against slash, I just don't see Moody as having the time for that sort of thing. Shoot first and fantasize later, maybe ....
Moody makes time for every potential threat and for the occasional artifact hunt. You can argue it's not one of his priorities, but he's not exactly pressed for time should he so wish. A much bigger problem is the inevitable distraction. He can have time-turned selves and possibly allies watching his back, his currently active enemies, and Quirrell's potential plots, but so can Quirrell. And there are probably more dark wizards who would benefit from Moody being distracted than the reverse. And is Moody even an Animagus? If not, or depending on his form, that's another advantage for Quirrell. They could take an Unbreakable vow to abstain from shenanigans while on dates, but that's way too big a constraint for either to accept, doesn't stop third parties, and is probably full of loopholes.
An Unbreakable vow requires one party to sacrifice the possibility of freely trusting the other party. That's not a healthy relationship.
Sexual tension based on how fascinatingly brilliant each person is at trying to kill the other is rarely conducive to trust and healthy relationships. People are notoriously more tolerant of fucked up relationship dynamics under stressful conditions; a battle to the death with the world at stake would qualify.
8Joshua Hobbes11y
Some of us are going to need a link explaining this system.

That, if anything, makes the system less clear.

Okay, some explanation: I took drethelin's "showdown/makeouts" line to be an oblique reference to Homestuck, a long and rambling webcomic saga which prominently features a number of character relationships that might be described in such terms. If this assumption is false, the comment doesn't make much sense. So I responded in terms of the "quadrants" used by Homestuck's troll characters to describe their romantic lives. There really isn't any simple explanation of these, but this is as good as any.

Yes there is a simple explanation.

Some relationships (♥ and ♠) involve intense, romantic, sexual passion, whereas others (♦ and ♣) are quieter, more reasonable, and closer to friendships and other platonic relationships. Also, some relationships (♥ and ♦) are based on positive feelings, whereas others (♠ and ♣) are based on negative ones.

♥ (violent positive) is passionate romantic love. ♦ (quiet positive) is deep platonic attachment. ♠ (violent negative) is a love/hate relationship. ♣ (quiet negative) is smoothing things over between a feuding pair.

Point of order: the caliginous quadrant is not love/hate; it's all hate, but in a sexualized way. You have to genuinely dislike someone to be ♠ for them.
You mean that the one time I try to rely on how vague English is about feelings and just use "love" for "fascination, sexual tension, importance in one's life" it's not proper usage? That's it, I'm suing the Ingaevones.
I've read that, and I'm no more enlightened. However, I approve of in-jokes, so I've taken away my downvote. Also, now I know that I should never, ever read Homestuck, so that's something.
That's a shame. If there's one thing that Homestuck does right, it's time travel (and actually thinking through and writing what a world with casual time travel and timeline enforcement would look like.)
Er, okay? That's not my objection.
This is a reference to the webcomic/multimedia series Homestuck by Andrew Hussie, which features a species of timetravelling aliens known as the Trolls due to fact that the first ones that the protagonists meet were actual internet trolls. The Trolls have their own wierd system of romance built around four quadrants: the flushed quadrant (denoted with a ♥) which loosly aproximates what humans think of as romantic love; the pale quadrant (♦) which is sort of an intense platonic friendship wherein one partner serves as a stablizing force on the other, more unstable partner; the ashen quadrent (♣) whereby one partner attempts to mediate between to otherwise violently opposed partners; and the caliginous quadrant (♠), which can be described as "romantic hate", and involve such things as "hatesnogging" and "murderfondling". A more detailed description can be found here. It should also be noted that this thread already contains at least on reference to a Hussie creation (cousin_it's "HP: Punch AM in snout to establish superiority"), so it's likely that fubarobfusco was primed to interpret things in that light.

Given Moody's CONSTANT VIGILANCE I wouldn't be surprised at him randomly dropping false information into conversations, especially with suspiciously skilled young wizards...

Moody drops all sorts of information, true and false, in his conversations and, when meeting that person again, will see if they recall it.

This is one of the ways he tests for Polyjuice users, animagi, and evil twins.

I hope he also tests for information that is true that he hasn't actually given and wouldn't expect them to have.
This is also a great technique for mapping out social networks, conspiracies, etc.
In the Morverse, twins share a telepathic bond and are sort of the same person. Either both twins are good or both are evil.
Almost certain they aren't telepathic, they're just the same person. You don't have to be perfect rationalists to always agree, if you're irrational in exactly the same way, and have exactly the same information and priors.
/not sure if DanArmak and pedanterrific are serious or just joking
You don't get the Aumann references in all the Twins' POV sections? I'll go dig up some examples, then. Edit: Here we are:
I got the Aumann references, I was questioning the claim that they are telepathic or the same person (both of which possibilities are damaged by that quote), or whether it was just a joke on the Aumanning. (On a side note, that reminds me that we still haven't found out how the Skeeter prank was done. After pondering it and imagining myself to be Bruce Schneier, I figure it was an attack on the printer as the weakest link, possibly polyjuicing or otherwise impersonating the editor.)
Oh well yes, the "same person" bit was a joking reference to that. I thought I made that clear with the second sentence. Oops. And I always assumed, in the absence of evidence otherwise, that it was some mind manipulation of Rita and/or her editor- False Memory Charms, Confundus or Imperius- perpetrated by either Quirrell or Dumbledore.

On the other hand, given his preference for not losing the war against Voldemort he might perhaps avoid dropping too much random false information on a suspiciously skilled young wizard who is credibly alleged to be vital for winning that war.

On the other hand, wouldn't most people already know something like that? It seems like a pretty baldfaced lie, crying out for contradiction.
Perhaps Dumbledore simply ensouled the statues.
With the souls of his enemies, muhahaha.

The ritual involves getting right up next to your enemy and making a loud sucking sound.

Pansy now believes she won't be affected by Adava Kedavra, and wants to join the Death Eaters.

This would be an awesome prank to play on Pansy using a green light spell.

That's ... kind of disturbing, actually.
Yeah, my mental model of Harry was going "AAAAAAAAH!"
The comment about Avada being unblockable strikes me as Eliezer either not doing his homework or tweaking canon. If it were blockable in-universe Dumbledore would know this in addition to Moody (IIRC Dumbledore does one of the canon blocks) and would have pointed this out during the conversation (unless Dumbledore and Moody conspired beforehand to keep Harry ignorant of this for some reason, which, y'know, penalty for complexity).
Doesn't everyone make a big deal about the Unblockable Curse being blocked by Harry in canon, too? Or is that just in HPMOR?

Hmm. So Harry Potter Wikia seems to suggest that Avada is described as unblockable in canon, but what that seems to mean is that it isn't blockable by a shield spell or anything like that. Harry didn't exactly block it in canon; it hit him and he survived anyway because of the Power of Love. I'm updating mildly in the direction of Eliezer tweaking canon because he decided that the instances of Avada being blocked in canon were Rowling cheating.

Oog, now I'm semantically satiated on "block."

I've gotta say, that one threw me; it seems like the kind of thing that would have changed attitudes and usage of AK.

Hypothesis (not sure if it has been discussed before): Assuming QuirrelMort wants (only) immortality, at least from now on (since Harry proved his ability to kill dementors) QuirrelMort will go to great lengths to keep Harry alive. Dementors are the only threat to Quirrel's safety which he is unable to deal with himself (being unable to cast any form of the patronus), and which everyone else is only temporarily able to hold back.

So, my rambled thoughts go something like this: QuirrelMort's terminal value is immortality for himself only, he is unable to lov... (read more)

Quirrell says that dementors are the second most dangerous things, after adult wizards.
Yes, but he is speaking generally, to students who will (most of them) never be as deadly as he is. He has an excellent means, fully under his own control, of dealing with adult wizards: He is able to take apart a fully-trained Auror without breaking a sweat. He has no equally good means of dealing with a Dementor.
Just Apparate away!
In "Humanism" it is stated that, if you don't realise you are under attack, you can lose the ability to Apparate. (It's a happy thought, presumably.) Quirrell is particularly vulnerable to the Dementor's attack, same as Harry, so this might be particularly dangerous to him.
Would that destroy a Horcrux?
Presumably it wouldn't even affect the Horcruxes if they're hidden where we think they are. It would serve to make them kind of pointless, though. Eternity alone in a hellish wasteland, yay!
Well, he doesn't seem to mind the thought of "eternity alone". Although on reflection a canon Horcrux could be damaged by a fang and a sword, so they would probably just be atomized if exposed directly to a nuclear blast. Although if one of them is floating in magma...
Yeah, one's floating in magma- and none of the others are in places they would be exposed to a direct nuclear blast in the event of nuclear holocaust, either. And even if they were... the reason the fang and sword (and Fiendfyre) worked is because the criterion for destroying a Horcrux is "damaged beyond magical repair". Basilisk venom and cursed fire both have a distinctly magical quality of "no takebacks". Who knows of being reduced to constituent atoms by mundane means counts? (Probably it does, but it isn't certain.) But I assume it bothers him because if he wanted humanity eradicated, he could have accomplished it by now. And he didn't seem to take any pleasure in his belief that
It still doesn't make it certain to work for such a case in particular, but Snape's "From the rumors I have heard, Headmaster, Muggle weapons are only slightly worse than the more... recondite aspects of wizardry" seems to be evidence towards counting.
I had taken that to refer to the scale of mass destruction possible, but good point.
Oh, I know they aren't exxactly exosed in any case; but floating in magma implies some pretty hefty protective charms. The thing about that quote that bothers me is that he seems the be referring to himself as "one of us", genuinely worried that his world is in danger - not just cooly amused at their folly, or even irritated by their incompetence. Maybe I'm just reading too much into it. ... or maybe he's worried that without followers, there's no-one to bring him back? Spending time as "less than the meanest ghost" is implied to be unpleasant in canon IIRC.

On further consideration of the Moody fight - as soon as Harry walked into the office, shouldn't he have seen all his invisible copies as well? Ch. 56 -

Bellatrix was still transparent within the Cloak, but to Harry she was no longer hidden, he knew that she was there, as obvious to him as a Thestral. For Harry had only loaned his Cloak, not given it; and he had comprehended and mastered the Deathly Hallow that had been passed down through the Potter line.

For Harry had only loaned his Cloak, not given it

That seems like it answer your question: his invisible copies aren't borrowing the cloak from him because they are him.

OK. I'm thinking of this in terms of Harry being able to see Bellatrix because it's his cloak. Harry should then be able to see the other Harrys because they're also wearing his cloak, unless the Cloak distinguishes between "master" and "time-travelled master", or the "loan" part is significant enough that Harry wouldn't be able to see someone under the cloak if they just pick it up without him expressly loaning it to them. If that counts as "stealing" and transfers ownership then you could "loan" the Cloak to everyone and they'd never be able to take it from you. There's something unsettling about a cloak that hides you from everyone, except its Master, unless the Master is also you.
It seems reasonable that Cloak belongs to Harry. Then successive timetravels instatiate Cloak1 with owner Harry1, Cloak2 with owner Harry2, etc... What's unsettling is that Mad Eye can see through the true cloak of invisibility!
I think EY phrased it as "more narrowly-focused artifacts can defeat other artifacts in the area of their specialty", or something like that (does anyone have the reference?). Of course, that still seems odd, because the Cloak's specialty is "being invisible" and the Eye's is "seeing in every direction at once, seeing through solid objects, and seeing magic including hiding or invisibility spells". I must be missing something. Maybe the Cloak's specialty actually has to do with Death, and the mundane invisibility is a side effect?
Maybe it's something to do with order of construction. Either the Eye is more ancient and thus more powerful in general, or the Eye was made after the Cloak and therefore its creator knew about and wanted to defeat the cloak.

Oh yeah, obviously it would be more powerful since it was made before or after the cloak.

All of those Eye functions can be summed up as "seeing bloody everything" (presumably within some range of the user), which at least seems more narrowly focused than your description, so perhaps its creator thought so too, which seems to count for something here, what with the broom physics and all. That's a plausible thought on the Cloak, though.
Yeah, thinking about it a bit more, it might be that the Eye is actually specialized to "detect all hidden things" or something- you can't hide by being behind a wall, you can't hide by being behind the user, you can't hide by being invisible.
4Eliezer Yudkowsky11y
Hah, I wondered if someone would ask that. I reply that seeing through the Cloak is a 'requires concentration' ability. Harry deliberately doesn't concentrate before going back in time, because he doesn't want to fix anything via knowledge so as to leave himself freedom of action.
I would say a small edit is probably in order, because "as obvious to him as a Thestral" definitely doesn't come across as an ability that requires any concentration. But I think Karl's explanation is a much better one and should be canonical.
1Eliezer Yudkowsky11y
Fair point.
He doesn't feel or know of any of his other copies in any previous chapter, why would he know of those copies?

Ch 87:

It seems like Harry is falling prey to the typical mind fallacy in his conviction that it's impossible for anyone who hasn't entered puberty yet to experience romantic attraction.

He can't be an expert on everything, so I wouldn't be particularly surprised by his making what probably feels like a safe assumption, if prepubescent romantic attraction weren't common enough to have a well known colloquial name.

This is a case where human minds vary a lot more than a naive hormone-determinative view might suggest. Simply questioning my own social circle ha... (read more)

You got me there.

I'm bothered by Harry's "recovered memory" of Voldemort killing his mother. Firstly we are told, at the time of its first narration, that Harry almost-notices that something is wrong with it. Secondly, the recover-memories-from-before-you-were-verbal thing seems, I don't know, kind of off. It's the sort of thing that would be possible if popular conceptions of how memory is stored were true. And thirdly, while I can see James trying to hold off Voldemort - and incidentally, he can't even dodge the very first AK that Voldemort casts? Isn't he an e... (read more)

Apparation can be blocked. That's what makes Dark Wizards more dangerous than any other monster you might fight - you can't just Apparate away.
It can be blocked, yes, but this appears to be a fairly major jinx, the equivalent of a lot of capital equipment. Hogwarts is known to be anti-Apparation jinxed, as is Azkaban, but I don't recall any other places where it's mentioned. (Ministry of Magic, perhaps; implied by the workers there commuting in a fairly standard fashion instead of just Apparating from their homes.) It's not clear that it can be installed on an average wizard's home. Anyway, you'd think it would prevent inward, but not outward, Apparation by default; you don't want to be suddenly attacked but you might want to make a quick escape. Dumbledore captures (in that fanfic by Rowling, that is, not the canon) some Death Eaters by preventing their Apparation, but he has to duel them first, so he might as well have cast AK. All that aside, she's an experienced combat wizard with a few seconds to spare. If she can't Apparate, she still has the option og grabbing Harry, blowing a hole in the wall, and running. "Accio Broomstick", anyone? Or whatever flight spell Voldemort uses to go up the stairs without footsteps. Come to think of it, why were they hiding in an apparently average home without special defenses, and relying on mere secrecy? Put them in Hogwarts, with its layers upon layers of magical fortifications. Draco states that Hogwarts is an impregnable fortress, and presumably Voldemort thinks so too since he doesn't attack Dumbledore there and end the war at a stroke.

This has come up before in the tvtropes discussion thread, but personally I operate on the assumption that apparating in a combat situation is simply beyond the skills of most wizards. It requires deliberation, which is probably hard to muster when someone is firing death beams at you, and if you tried it you'd probably get splinched. It's probably doable for really exceptional wizards, like Voldemort or Dumbledore, but not for your average auror, let alone the average joe wizard.

Highly tactically useful feats that are extremely difficult to perform would be one major reason why some wizards can be so much more dangerous in a fight than others when wizards far from the top of the scale are capable of firing death beams.

Ok, that's a good point. So what about blowing a hole in the wall and fleeing into the night?
I assume that he'd catch her if she tried. He can fly.
As opposed to what happens when she sits about in a panic? "Accio Broomstick" is another helpful tactical option, here. Anyway, if he can fly, why can't she?
In canon, Voldemort's unassisted-flight spell was unique to him (until he taught it to Snape). He invented it, and it was considered rather impressive, and unprecedented.
Port keys? Those seem an obvious precaution in a wizarding war.
I can't think of any particular reason that wouldn't work, unless Voldemort or the Death Eaters in general have some way of stopping them prior to the attack. Maybe the anti-disapparition jinx (which is an area of effect spell rather than a targeted one according to the Potter wiki) also affects portkeys? Or perhaps there's another spell. The Death Eaters might simply jinx their targets' houses before attacking. If there weren't some way of preventing people from using them, I'd think having a portkey in the house in a readily accessible place, to teleport out of harm's way, would be standard response for anyone at particular risk in the war. Given that this apparently didn't stop the Death Eaters, I assume that it's preventable.
Given how poorly the war was going for the OotF I wouldn't be surprised if by that point they were suffering from a shortage of safe houses.
There's also the Floo.
I think canon suggests you're either part of the Floo network or you're not, meaning that if you were part of it, the Death Eaters could use it to get in, just as you could use it to get out.
The offices of Dumbledore and Snape and presumably the other Professors have Floo links.
Before the war, certainly. And even during, while Dumbledore was alive, Hogwarts was well enough protected that it probably wouldn't have been a good idea for the Death Eaters to try and get in by Floo, even assuming that they could. The Potter Wiki says that the Floo Network is governed by the Floo Network Authority at the Ministry of Magic, which probably keeps tabs on who's connected where, so being connected to the Floo Network may be incompatible with trying to keep your location strictly secret.
I was basically quoting Quirrell from his first DDA lesson. He says that he's teaching defense against wizards because they can keep you from being able to run. From this I drew the conclusion that wizards can keep you from being able to run, and this is a problem you might have to worry about in practice, even when facing wizards less powerful than Voldemort.
Mmm. He says This does not immediately imply that the anti-Apparation jinx is something that can be cast quickly, or under combat conditions. Most spells seem to require line of sight; if Voldemort has to be able to see you to jinx you, he might as well cast AK. The only times we actually see anti-Apparation in action, it is applied to places - Hogwarts, Ministry of Magic, Azkaban - not individuals.
I'm confused- you suggest Anti-Apparation spells are difficult to use because they probably require line-of-sight, then in the very next sentence acknowledge that we only ever see them as area-effect spells laid on locations. You don't think it's likely that all Anti-Apparation spells are area-effect, including the combat-time version that one might find oneself under the influence of while being attacked by Dark Wizards? It seems more reasonable to treat it as a tactical consideration if the jinx denies Apparation in a hundred-yard-radius sphere for five minutes, or something like that.
It seems to me that Potterverse magic comes in two distinct kinds. There are dueling charms that require line-of-sight, and this is what we actually see being cast. And then there are big area-effect magics like the ones affecting Hogwarts, and we don't really know anything about those - we never see them being cast. But we do see that such things are rare, and mostly old. This suggests to me that there's no area-effect combat spells, to be laid on in five minutes before you enter the enemy's house. Rather there are point-and-shoots, and Epic Ritual Magic, possibly lost to modern wizardkind. Touching Dumbledore's magic against the Death Eaters, note that he doesn't use it until they are defeated and presumably unconscious. This seems to indicate that it's an ordinary point-and-shoot, perhaps even a slow, easily-dodged one that's useless on an active target. A point-and-shoot anti-Apparation jinx is useless to Voldemort; if he can jinx you that way he might as well use the AK.
The original canon didn't really have the Lost Golden Age elements of MoR. We don't see a lot of area-affecting spells actually being cast, but we do have stuff like Fred and George turning part of Hogwarts castle into a swamp, in a manner such that Professor Umbridge couldn't turn it back. In the original canon, it seems more like spells of this sort simply require some know how and competence that might be beyond the average coasted-through-school-and-forgot-everything-they-didn't-need wizard, but isn't beyond clever and mischievous upper year students. I think the reason this kind of magic appears so little on screen is that Rowling simply couldn't be arsed to come up with rules for how her magic worked beyond the "point and say words" type, so she mostly kept anything with more complicated mechanics offstage.
Such as canon!Harry Potter.
If we're talking about canon, I want to point out that they cast an Anti-Disapparation jinx over Hogsmeade in Deathly Hallows, when it was perfectly possible to apparate before. So at the very least we know the ability to cast it on an area isn't lost to wizardkind. And to address the more general idea, you may well want to cast a Muffliato or Repello Muggletum over someone's house before you break in, to avoid attracting attention. Or it may also indicate it takes ten seconds to cast.
IIRC, in book 5 of canon, after the battle in the ministry, Dumbledore tells Fudge that the captured Death Eaters are in the Department of Mysteries, and that he has "bound them with an Anti-Disapparition jinx". This implies that this jinx is at the very least one that is capable of being cast easily and quickly enough to be a viable way to stop captured prisoners from escaping. (Although not necessarily under combat conditions.)
"that fanfic by Rowling"? Heh.
Rowling-canon strongly implies that Dumbledore was the reason Voldemort didn't attack Hogwarts; that is, Dumbledore's presence at Hogwarts protected the castle, and not the other way around. Hogwarts fell very soon after Dumbledore's death. However, while Dumbledore may have prevented Voldemort from outright capturing Hogwarts, in the same way he stopped Voldemort from outright capturing the Ministry, he proved unable to prevent Voldemort and friends from repeatedly sneaking into the castle, and he doesn't have the time to personally guard the Potters 24/7.
The last paragraph makes a good point. In a world without the Fidelius, why wouldn't they be at Hogwarts? Hmm.
It may not be a world without the Fidelius Charm; Lupin implies that the betrayal of a secret keeper was still what did them in. It may simply be that the charm may Never Be Mentioned Again, because if it's allowed to function as more than a one-time plot device, it breaks the story, so we're just going to have to shove it in the corner and pretend it's not there anymore.
Cross-posted from the TVTropes forum. (There's more to the post there, but I didn't think it all needed to be repeated.) Why would this important? Well, obviously, this memory represents a huge turning point for Harry. This is when he started to turn against Dumbledore. It suggested to him an interpretation of his parents' death in which Du