Worth noting - it is immediately after that laughter that he gives over his father's rock. And given that this chapter comments on how Dumbledore has access to wacky divination, that rock starts to make a heck of a lot more sense. (I mean, we always knew it's be an Important Quest Item, but this does shed a bit of light on why)
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 110.
There is 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.)
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: