Free will as opposing "determinism" is a confused concept according to Eliezer's opinion, and also according to mine -- see Thou Art Physics
Basic points is that we're part of the physical world-- if free will means anything, it must mean the ability of our current physical state to determine our decisions. "Libertarian free-will" in the sense of people making decision that can't be predicted from the current state; that's inevitably just randomness, not anything that has to do with people's character traits or moralities or cognitive-processes -- nothing that is traditionally labelled "free will".
But the Potterverse is dualist. Even if horcruxes get some massive retcon, animagi preserve that in MOR.
So maybe souls are immune to the normal patterns of time and causality, and a decision from the soul has special properties for prophecy. Only when all involved souls have chosen does the timestream become fixed enough for prophecies. I'm not sure what that means for time turners. Maybe people who have gone back are out of contact with their souls.
This would cost the story applicability, but it is a story, not a treatise.
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.
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: