It certainly looks like Harry is a horcrux in this universe, and Harry already thought of that possibility in different terms, yet the Sorting Hat says...
The exact phrasing of the Sorting Hat's statement was as follows:
...there is definitely nothing like a ghost - mind, intelligence, memory, personality, or feelings - in your scar. Otherwise it would be participating in this conversation, being under my brim.
Now, anyone that's read the sort of fairytale where riddles are important should immediately be able to come up with a half-dozen loopholes in that, but I think we can dismiss most of them out of hand given that the Sorting Hat has no particular incentive to be misleading. The most promising option that remains, by my reading, is that there's nothing separate about the Horcrux contents for the Hat to key off of -- they effectively are Harry, or part of him. He's probably tapping that part of himself when he has his Dark Side episodes, at the very least, but I don't think that's the full extent of the Horcrux's influence: at various points he asks himself or people around him why he doesn't think like other children, and narrative parsimony points rather strongly to the one unique trait we know he has.
The weakest point of this theory, as best I can tell, is the lack of any (obvious) memories from Voldemort; I think we can safely assume the Hat would have found them if they were locked away somewhere within him, but on the other hand it'd be a rather poor resurrection that resulted in an amnesiac personality-clone. Riddle's diary from Chamber of Secrets also argues along these lines. Unfortunately, we haven't seen any other Horcruces in MoR, so we have nothing in-universe to compare against, and canon may not be reliable. Perhaps the relevant memories got wiped out by infantile amnesia or something.
It seems to me that the horcrux doesn't need memories. The stored fragment of the soul serves not as a means of resurrection, but to sort of "anchor" the soul to the living world. So the main part of the soul, the part that stays within the living body until death, is left to linger. There is evidence for this: in canon, the first time Voldemort dies, his soul still lives, gathers strength, and then gets a servant to help him, without any contact with the horcruxes.
And I expect that Voldemort actually planned on making Harry a horcrux; what better protection against a prophetic rival than to make him have to suicide to kill you?
The next discussion thread is 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 85. The previous thread has long passed 500 comments. Comment in the 15th thread until you read chapter 85.
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: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15.
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