It's not as fuzzy/rich as human languages, so it's harder to do it, but it's always possible to only say half of the truth which opens all doors to careful manipulation
Richness isn't the only limiting factor. When Harry did his 2+2=3 experiment he automatically said 4. That seems the language automatically makes things that reveal the intention to come out.
It's a good thing that he tried to say 3 and not 5. Otherwise we'd be debating whether snake-language might not be rich enough to include 5. (Compare rabbit language in Watership Down, which has a single word for all numbers above 4, variously translated in the text as 5 or 1000.)
Two new short chapters! Since the next one is coming tomorrow and we know it'll be short, let's use one thread for both.
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 105 (and chapter 106, once it comes out tomorrow). EDIT: based on Alsadius' comment about thread creation for MOR chapters, let's also use this thread for chapter 107 (and future chapters until this nears 500 comments) unless someone objects to doing so. Given that this is the final arc we're talking about, thread titles should be updated to indicate chapters covered.
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: