Three days ago, Eliezer Yudkowsky posted the first update in a long time to Harry Potter and the Methods of Rationality, his excellent Harry Potter fanfic. A note at the beginning of the chapter has suggestions for which chapters to re-read in case you’re having trouble remembering what’s happened already. I just wasted an evening re-reading those chapters, searching for clues as to what happens next, because the next update is supposed to be tomorrow and I wanted to test my ability at prediction making. Most of you can ignore this post, but for those who are fans of the fic, my predictions are below the fold, and I’d be happy to hear yours as well.
First of all, I predict that Sirius Black will soon be making an appearance in the fic. This is because, among the chapters Eliezer suggested re-reading were chapters where Harry received messages from a mysterious benefactor. In canon, Sirius was a mysterious benefactor to Harry, and in the fic the mysterious benefactor’s messages strongly implied he knew Harry’s father very well, and came with some evidence of this. So the mysterious benefactor has to be Sirius.
Unless it’s Peter Pettigrew. But the intentions of the mysterious benefactor seem to genuine for that, unless Pettigrew really is a good guy in this universe. And while we know Pettigrew didn’t never hid out as the Weasley family rat, and Eliezer has Harry come down really hard on the alleged ridiculousness of Sirius Black having been framed, my guess is that Eliezer decided to leave that part of the Harry Potter mythos unchanged. In the author’s notes for chapters 33-34, Eliezer gives a list of possible reasons for changes to the story relative to canon, and none of them seem to cover making Peter Pettigrew good. They do say, however:
Writing a children’s book is much harder than writing a story for grownups. I can’t do it. Therefore this is a story for grownups… and that means it is impossible that an evil Peter Pettigrew is hiding out as Scabbers, the pet rat of an enemy wizarding family. In a children’s book, this can be taken in passing. In a story for grownups, it would mean Pettigrew was holding the Idiot Ball. It is a general law of MoR that no one is ever holding the Idiot Ball.
This suggests that the betrayal of Harry’s parents, and the Sirius/Pettigrew confrontation, both happened as in canon, but Pettigrew just did something smarter afterwards.
Second prediction: I predict that Mr. Hat and Cloak will be revealed to be an agent of Lucius Malfoy. Lucius is utterly horrified at the thought of his son becoming friends with Hermione, and no one else has the motivation to go to such ridiculous lengths to hurt Hermione. Lucius also has reason to want to turn Quirrell against Dumbledore (see chapter 35): he probably doesn’t know all that much about Quirrell, but probably knows enough to figure turning Quirrell against Dumbledore would hurt Dumbledore, and Lucius hates Dumbledore.
Given what I’ve said so far, it just feels right for Peter Pettigrew to turn up soon too, especially if he did something relatively smart after faking his death. Maybe he’s Mr. Hat and Cloak? That actually kinda makes sense, if he went to Lucius to say, “please hide me!” after faking his death and Lucius decided to use him for dirty work.