In Methods of Rationality, the Weasley twins refer to the Map as being part of the Hogwarts security system. So it probably gets the information from the wards.
Yes, but how do the wards get people's names? It's not like the name "Ron Weasley" is tattooed on every molecule of the boy's body.
True Names are a feature of some systems of magic — Earthsea comes to mind — but not of the canon Potterverse, nor of MoR as far as I can recall. In canon, the name "Voldemort" has unusual power because of specific spells keyed on it, and it's an adopted name.
Real-time Legilimency? If so, we would expect the map to display whatever name matched a person's self-image; and a sufficiently potent Occlumens could be expected to fool it by sufficiently good Method acting.
On the other hand, there's a subsystem of Hogwarts Castle that does get told the name of every student on their first day, and has a close-up chance to read it from them by what resembles Legilimency: the Sorting Hat. Possibly a similar system is in place for professors and others ... which involves the Headmaster drawing a circle ...
This was recently discussed here. I came up with this specific idea here.
The 'drawing a circle' thing: Dumbledore expects Riddle to show up on the Map as Riddle forty-five years after he graduated. Apparently student records are preserved; professors wouldn't need to be named to the wards unless they weren't alumni.
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 84. The previous thread has passed 500 comments. Comment in the 14th thread until you read chapter 84.
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.
As a reminder, it’s often useful to start your comment by indicating which chapter you are commenting on.
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