The Map was an extraordinarily powerful artifact, capable of tracking every sentient being on the school grounds, in real time, by name. Almost certainly, it had been created during the original raising of Hogwarts. It was not good that errors were starting to pop up. Chances were that no one except Dumbledore could fix it if it was broken.
And the Weasley twins weren’t about to turn the Map over to Dumbledore. It would have been an unforgivable insult to the Marauders—the four unknowns who’d managed to steal part of the Hogwarts security system, something probably forged by Salazar Slytherin himself, and twist it into a tool for student pranking.
Yes. There are a couple routes he might have learned of it, though:
Slytherin’s monster, as a high-level creature keyed into the deepest wards, might be expected to know of it or be able to learn of it.
If my speculation about the Map’s anomaly is right, Voldemort’s spirit could have learned of it by directly observing the twins.
The Map has been passed down through the ages and sometimes even been in official possession, so it could be mentioned in some obscure book. Possibly it might be a headmaster secret, explaining how Dumbledore learned of it without requiring him to invade their minds.
The twins could have been suspiciously—to Quirrel—adept at avoiding professors and obstacles, prompting him to spy on them as one would expect Quirrel to do.
The Map could be revealed at a future date; Quirrel’s suspiciously good priors have long been speculated as being related to time travel.
None of them seem especially likely, but in aggregate with other strategies I have failed to think of...
Ah. In that case the Ministry probably doesn’t have one. Though I still doubt there’s not a way Quirrell could get around it.
I think quirrel couldn’t get around it because he might not know it even exists.
Yes. There are a couple routes he might have learned of it, though:
Slytherin’s monster, as a high-level creature keyed into the deepest wards, might be expected to know of it or be able to learn of it.
If my speculation about the Map’s anomaly is right, Voldemort’s spirit could have learned of it by directly observing the twins.
The Map has been passed down through the ages and sometimes even been in official possession, so it could be mentioned in some obscure book. Possibly it might be a headmaster secret, explaining how Dumbledore learned of it without requiring him to invade their minds.
The twins could have been suspiciously—to Quirrel—adept at avoiding professors and obstacles, prompting him to spy on them as one would expect Quirrel to do.
The Map could be revealed at a future date; Quirrel’s suspiciously good priors have long been speculated as being related to time travel.
None of them seem especially likely, but in aggregate with other strategies I have failed to think of...