In the real world? The second, unconditionally.
In fantasy fiction that runs on narrativium? Especially fiction that is known to be full of hints, foreshadowing, and clues that the author put there? The first.
The whole point of this story (or one of them) is that it is not intended to run on narrativium, that people make decisions and things happen for rational, believable, predictable reasons. It is a puzzle meant to be solved, using the information given rather than appeals to tropes and meta-thinking.
Also, even if you were right, this is just a really terrible scenario. While there is foreshadowing of Harry ending the world thanks to the latest prophecy, there have been no other clues whatsoever pointing at centaurs, or a special role for Lily in causing the apocalypse, or any other point whatsoever that the theory relies on.
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 chapters 91 & 92 . The previous thread has 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: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17,18,19,20.
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: