The new thread, discussion 13, is here.
This is a new thread to discuss Eliezer Yudkowsky's Harry Potter and the Methods of Rationality and anything related to it. With three chapters recently the previous thread has very quickly reached 1000 comments. The latest chapter as of 25th March 2012 is Ch 80.
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: one, two, three, four, five, six, seven, eight, nine, ten, eleven.
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Eliezer Yudkowsky which is not supposed to be publicly available (which includes public statements by Eliezer that have been retracted).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.
Short detour back to chapter 79, to look closely at the night's events:
At midnight, Draco and Hermine meet for the duel. (Let's assume they did have a duel, because implanting very believable (but still false) memories into both of their brains would take about twice the time of the duel and would thus be unnecessary work.) Let's assume that the duell takes about 15 to 20 minutes, so it's now 12:20am. Enter Mister X. Mister X stuns Draco, implants false memories (< 1 min) into Hermione's brain of her doing the Blood-Cooling Charm, and finally performs the Blood-Cooling Charm on Draco in a way to make sure he survives for >6 hours. Mister X is back in his room at 12:30am and needs to wait 6 hours (plus epsilon) until all traces leading to him have vanished.
And guess what:
Some Bayesian updating on P(Quirrell did it | Quirrell found Draco at 6:33am) tells us that this increases the probability of "Quirrell did it" by a quite noticeable amount.
OTOH, I'm not sure whether it would be okay to just do the math, without taking into account the possibility that Eliezer chose that time deliberately to steer us in a certain direction. Any thoughts on that?
This is contingent on whether the duel would last for 15-20 minutes. To my (admittedly leaky) memory, we haven't seen a proper duel in MoR yet, and I don't believe that any duel in canon lasted for that long either.