However, this does raise an interesting and completely tangential question about the Map. How does it know everybody’s name? What ‘database’ does it—or rather the enchantment that it is an interface for—make reference to?
An obvious answer would be birth certificates. It is not (too) unreasonable to suppose that wizards have them too, and that the Map is clever enough to map people to their birth certificates. I have no idea how it would do this, but in any case I don’t think this can be how the Map works.
First, what if my birth certificate is destroyed? Of course I can get a replacement, but there will be a period in which there is nothing the Map can refer to in order to determine my name. It could ‘cache’ my information, I suppose. But what if a baby is born in Hogwarts? What does the Map say before the baby is named?
This leads into the second, larger, problem. The enchantment that the Map is an interface for is supposed to be part of the Hogwarts security system. I’ve gotten the impression that Hogwarts was raised all at once by the Founders; the enchantment in question would have been cast then. ‘Then’ is the 9th or 10th century, according to canon. “Civil registration” of births didn’t begin in the United Kingdom until 1837. Prior to that I think births were often registered with churches, but surely there were many whose names had no official status; they had ‘common-law’ designations (this still must occur often).
This discussion reminds me of the “Bag of zahav” experiment of Chapter 6.
And therefore the answer is “Magic, Mr. Potter” and “It just uses your name.” This doesn’t predict much, but it allows us to eliminate obviously nonmagical hypotheses like a database that reads in names announced during Sorting. That’s just not how the Hogwarts founders would have thought about the problem.
I guess that a baby that hasn’t yet received a name would be known as “Mr. Potter” or “The Potter baby” or something equally vague.
That’s just not how the Hogwarts founders would have thought about the problem.
That doesn’t mean the Founders could do the impossible. Saying that “it just uses your name” might be true, but it doesn’t tell us how it can use your name. There must be a way that it works (although it may very well be that there is no consistent way-that-it-works that can be extracted from the text). Compare this to another example in which the creator of an artifact “thought about the problem” differently:
Broomsticks had been invented during what a Muggle would have called the Dark Ages, supposedly by a legendary witch named Celestria Relevo, allegedly the great-great-granddaughter of Merlin.
Celestria Relevo, or whichever person or group had really invented those enchantments, hadn’t known a darned thing about Newtonian mechanics.
Broomsticks, therefore, worked by Aristotelian physics.
They went where you pointed them (ch 59).
Broomsticks don’t work the way we would expect them to work, because that’s not how Celestria Relevo thought about the problem, but that doesn’t meant there isn’t a way that they work.
Saying that “it just uses your name” might be true, but it doesn’t tell us how it can use your name. There must be a way that it works.
To clarify, what I believe is that magic works in a top-down way, not a reductionist way. If you were writing a computer program, you would have to specify where the name comes from and what to do in marginal cases. But the Founders believed that each individual came with an XML-tag name attached to them, and the map just tries to figure out that name.
I realize this is an incomplete theory because it doesn’t explain what the map does in weird borderline cases (although I can make guesses). I am using this theory (which we can derive by comparing the map to Harry’s pouch, and to broomsticks, and to Transfiguration) to reject hypotheses that involve a reductionist, computer-program approach to magic.
The reason Voldemort brainwashed Bellatrix was in order to marry her in absolute secrecy, unconventionally taking her last name for his own (this is also the reason she is not married to Lestrange in MoR). As a result, his name will show up as “Tom Black” on the map, and Dumbledore’s “Find Tom Riddle” instruction will do nothing.
My guess is that, in the world of HP:MoR, the Simulation Argument is true. Muggle science works within the boundaries of the simulation; magic operates directly on the underlying data structures, bypassing most of the Muggle-oriented interfaces by using debugging APIs. That’s why it has rules that make some sort of sense, but that don’t correspond to most laws of nature as Muggles understand them. Of course, the virtual machine that powers the “reality” of HP:MoR is fairly robust, which is why magic is relatively safe (i.e., you can’t crash the whole of reality with a miscast Lumos), and also why magic is not all-powerful (those debugging APIs are still fairly limited).
This discussion reminds me of the “Bag of zahav” experiment of Chapter 6.
My original guess at why names are needed for magic was that the Source of Magic uses the names as pointers to the information in other people’s heads.
“It can understand nouns, but not noun phrases that mean the same thing? The person who made this probably didn’t speak Japanese and I don’t speak any Hebrew, so it’s not using their knowledge, and it’s not using my knowledge—”
It’s using everyone else’s knowledge. This would explain why wizards can transfigure things which have been discovered but not created, like CNTs, but can’t transfigure Alzheimer’s cures. Sadly, this possibility would be undermined by ‘Tom Riddle’ appearing on the map, since almost everyone knows him as Voldemort.
Maybe it works by a registry of current and former students and faculty at Hogwarts, and people who are neither show up as “Intruder (number)” or something. In modern Wizarding Britain this would include basically everyone.
I mean, if the Founders created the Map as part of the Hogwarts security system, they wouldn’t have been all that concerned with putting a name on everyone who could possibly step foot on the grounds, they’d just want to be able to locate students and differentiate them from anyone else.
I can’t remember, did the Beauxbatons and Durmstrang delegations show up on the Map in GoF? Not that it really matters, the canon!Map and MoR!Map are different enough that it wouldn’t be much evidence.
This theory, unlike the birth certificate one, can easily explain how the Map matches people with names. During the Sorting, McGonagall reads aloud a name, and the next person who puts on the Sorting Hat is assigned that name. (Assuming the Hat is hooked up to the security system, or vice versa.)
Actually, that’s even better- we have a known mechanism by which (something that could be hooked up to) the Hogwarts wards can read minds to determine names. So it actually doesn’t require some extraneous piece of paper or database or whatever, but on the other hand would only work on people who’ve been Sorted.
It’s not clear. When Crouch is confessing everything under Veritaserum, he says that he saw his father entering the grounds on the Map, and so headed into the grounds to intercept him. He says something along the lines of “Then Potter came, and Krum”, and it’s ambiguous as to whether he sees them appear on the Map or if he sees them him person.
From a Muggle point of view, maybe. From a Wizard point of view, that’s probably the least obvious answer.
Your name is your name, and no piece of paper can grant it or take it away.
If I were to venture a guess, I’d say that a person’s name would be something like “$givenName $familyName”, such as “Harry Potter” or “Albus Dumbledore”. The givenName is the name your parents gave you when you were a baby. The family name is the name of your Noble House (“Malfoy”, “Potter”, etc.), or simply the last name which your parents share (“Granger”). This is the naming convention that (as per my guess) wizards and witches have been using since the time of Merlin, so it’s reasonable to assume that the creators of the Map imbued it with the same rules.
As to the question, “yes, but how does the Map compute the values of givenName and familyName for any specific person”, the answer is, “Magic”.
When he was alone in the room, the old wizard looked down at the map, which had now written upon itself a fine line drawing of the Gryffindor dorms in which they stood, the small handwritten Albus P.W.B. Dumbledore the only name left therein.
Ah, yes, good catch. Though we could probably count middle initials as part of the given name, since they are granted to the baby by its parents at the same time as the givenName… aren’t they ? I’m actually not entirely sure how middle initials work in Britain.
Your name is your name, and no piece of paper can grant it or take it away.
If the world of HPMOR is some sort of simulation, as you claim, then this is true and significant; your name exists as a fixed value that can be referenced by a program like the Map. But if the world of HPMOR is more like our own, then to say “your name is your name” is pretty empty; like most everything else, there is an explanation of why your name is your name. In our world, what makes it true that we bear the names we do is not that we all have own values for the variable $name. Rather, what makes it true is some other fact; one possibility (one that I don’t believe myself) is that what makes it true that my name is Alex is the fact that my birth certificate reads ‘Alex’.
So I think our disagreement arises from what we think the world of HPMOR is like.
If the world of HPMOR is some sort of simulation, as you claim, then this is true and significant; your name exists as a fixed value that can be referenced by a program like the Map.
I think these are two separate issues.
One issue is concerned with the wizards’ concept of names. The wizards who created the Map would seek to imbue it with whatever naming convention felt right to them.
The other issue is concerned with how the HP:MoR universe works, and which resources the Map can tap in order to implement its functionality.
These issues are somewhat related, but they aren’t identical. We could very easily envision a world where names are stored on birth certificates, and yet the wizards still believe that, even if Mr. Harry Potter goes through life calling himself “Mr. Spoo”, his name is still Harry Potter, because that’s what his parents, Mr. and Mrs. Potter, called him. On the other hand, we could envision a world where names are stored in some underlying data structure in the simulation, and yet the wizards believe that what a person calls himself is more important than whatever name parents gave him. Or we could envision some combination of the two.
That said, IMO no wizard would conceive of actually perusing the birth certificate database for anything; nor would he deliberately enchant a map to do anything of the sort. For all we know, wizards and witches don’t even have any birth certificates. It’s pretty likely that, even if they do have birth certificates, they don’t have any centralized databases that store them; we never seen any wizard use one, IIRC, neither in canon nor in MoR.
So, “how does the Map work ?” Well, it works the same way Harry’s Mokeskin Pouch works: by magic.
Other than the “external database” option, the only other sources of name information I can think of are:
The mind of the person being mapped
The mind of the person reading the map
A sort of consensus of how everyone in Hogwarts knows someone
I feel that picking someone’s name from their own mind seems the most elegant and consistent. It doesn’t handle babies (Before the parents choose a name, can a baby even be said to have one? Babies would have to be special-cased regardless), but it does allow arbitrary people to be mapped (multiple strangers being indistinguishable from each other seems like a serious flaw in a security system) and requires no external registry. On the one hand, it seems like interrogating the mind of every human is vastly more complicated than just looking up the name in a database, but to the kind of epistemology which would seem obvious to a 9th-century witch or wizard I can see it being “obvious”.
(And to respond to your question about Pettigrew in the great-grandparent, I would assume that the map skips over animals entirely, which would probably include animagi. This would tend to lend a slight amount of weight to my “the map displays your name as you know it” theory, as if the names came from how everyone else around you knew you there would be no reason not to include pets.)
If my theory is true, it raises an additional interesting question: Is it possible to obliviate yourself selectively so that you lose all knowledge of your own name? (Possibly storing the memories in a pensieve first so you can recover them later) And if so, is the map the only piece of the Hogwarts security system which might be impeded by this?
A further idea: Professor Quirrel is shown to take a very loose approach to identity and names (“Identity does not mean, to such as us, what it means to other people.”) Possibly Quirrelmort is the constant error, not because his name is wrong, but because he doesn’t have a name attached to his marker at all.
And to respond to your question about Pettigrew in the great-grandparent, I would assume that the map skips over animals entirely, which would probably include animagi.
A large part of the plot of Prisoner of Azkaban hinges on the fact that Lupin noticed Pettigrew on the Map while he was in rat form.
Is it possible to obliviate yourself selectively so that you lose all knowledge of your own name?
In Quirrell’s case, he may be a powerful enough Occulumens to prevent the Map from reading his mind and so learning his name (if your theory is correct).
A further idea: Professor Quirrel is shown to take a very loose approach to identity and names (“Identity does not mean, to such as us, what it means to other people.”) Possibly Quirrelmort is the constant error, not because his name is wrong, but because he doesn’t have a name attached to his marker at all.
I’m not saying this is true. But I hope it is because it would be awesome.
Quite right, I completely overlooked that.
However, this does raise an interesting and completely tangential question about the Map. How does it know everybody’s name? What ‘database’ does it—or rather the enchantment that it is an interface for—make reference to?
An obvious answer would be birth certificates. It is not (too) unreasonable to suppose that wizards have them too, and that the Map is clever enough to map people to their birth certificates. I have no idea how it would do this, but in any case I don’t think this can be how the Map works.
First, what if my birth certificate is destroyed? Of course I can get a replacement, but there will be a period in which there is nothing the Map can refer to in order to determine my name. It could ‘cache’ my information, I suppose. But what if a baby is born in Hogwarts? What does the Map say before the baby is named?
This leads into the second, larger, problem. The enchantment that the Map is an interface for is supposed to be part of the Hogwarts security system. I’ve gotten the impression that Hogwarts was raised all at once by the Founders; the enchantment in question would have been cast then. ‘Then’ is the 9th or 10th century, according to canon. “Civil registration” of births didn’t begin in the United Kingdom until 1837. Prior to that I think births were often registered with churches, but surely there were many whose names had no official status; they had ‘common-law’ designations (this still must occur often).
So how does the Map work?
This discussion reminds me of the “Bag of zahav” experiment of Chapter 6.
And therefore the answer is “Magic, Mr. Potter” and “It just uses your name.” This doesn’t predict much, but it allows us to eliminate obviously nonmagical hypotheses like a database that reads in names announced during Sorting. That’s just not how the Hogwarts founders would have thought about the problem.
I guess that a baby that hasn’t yet received a name would be known as “Mr. Potter” or “The Potter baby” or something equally vague.
That doesn’t mean the Founders could do the impossible. Saying that “it just uses your name” might be true, but it doesn’t tell us how it can use your name. There must be a way that it works (although it may very well be that there is no consistent way-that-it-works that can be extracted from the text). Compare this to another example in which the creator of an artifact “thought about the problem” differently:
Broomsticks don’t work the way we would expect them to work, because that’s not how Celestria Relevo thought about the problem, but that doesn’t meant there isn’t a way that they work.
To clarify, what I believe is that magic works in a top-down way, not a reductionist way. If you were writing a computer program, you would have to specify where the name comes from and what to do in marginal cases. But the Founders believed that each individual came with an XML-tag name attached to them, and the map just tries to figure out that name.
I realize this is an incomplete theory because it doesn’t explain what the map does in weird borderline cases (although I can make guesses). I am using this theory (which we can derive by comparing the map to Harry’s pouch, and to broomsticks, and to Transfiguration) to reject hypotheses that involve a reductionist, computer-program approach to magic.
The Founders may have been Truenamers, in which case each person who walked in would have a singular name attached to them.
So the Map can’t find married women?
The reason Voldemort brainwashed Bellatrix was in order to marry her in absolute secrecy, unconventionally taking her last name for his own (this is also the reason she is not married to Lestrange in MoR). As a result, his name will show up as “Tom Black” on the map, and Dumbledore’s “Find Tom Riddle” instruction will do nothing.
My guess is that, in the world of HP:MoR, the Simulation Argument is true. Muggle science works within the boundaries of the simulation; magic operates directly on the underlying data structures, bypassing most of the Muggle-oriented interfaces by using debugging APIs. That’s why it has rules that make some sort of sense, but that don’t correspond to most laws of nature as Muggles understand them. Of course, the virtual machine that powers the “reality” of HP:MoR is fairly robust, which is why magic is relatively safe (i.e., you can’t crash the whole of reality with a miscast Lumos), and also why magic is not all-powerful (those debugging APIs are still fairly limited).
My original guess at why names are needed for magic was that the Source of Magic uses the names as pointers to the information in other people’s heads.
It’s using everyone else’s knowledge. This would explain why wizards can transfigure things which have been discovered but not created, like CNTs, but can’t transfigure Alzheimer’s cures. Sadly, this possibility would be undermined by ‘Tom Riddle’ appearing on the map, since almost everyone knows him as Voldemort.
Maybe it works by a registry of current and former students and faculty at Hogwarts, and people who are neither show up as “Intruder (number)” or something. In modern Wizarding Britain this would include basically everyone.
I mean, if the Founders created the Map as part of the Hogwarts security system, they wouldn’t have been all that concerned with putting a name on everyone who could possibly step foot on the grounds, they’d just want to be able to locate students and differentiate them from anyone else.
I can’t remember, did the Beauxbatons and Durmstrang delegations show up on the Map in GoF? Not that it really matters, the canon!Map and MoR!Map are different enough that it wouldn’t be much evidence.
This theory, unlike the birth certificate one, can easily explain how the Map matches people with names. During the Sorting, McGonagall reads aloud a name, and the next person who puts on the Sorting Hat is assigned that name. (Assuming the Hat is hooked up to the security system, or vice versa.)
Actually, that’s even better- we have a known mechanism by which (something that could be hooked up to) the Hogwarts wards can read minds to determine names. So it actually doesn’t require some extraneous piece of paper or database or whatever, but on the other hand would only work on people who’ve been Sorted.
So no foreign professors!
I couldn’t swear to it, but I thought the map showed Krum in GoF.
It’s not clear. When Crouch is confessing everything under Veritaserum, he says that he saw his father entering the grounds on the Map, and so headed into the grounds to intercept him. He says something along the lines of “Then Potter came, and Krum”, and it’s ambiguous as to whether he sees them appear on the Map or if he sees them him person.
From a Muggle point of view, maybe. From a Wizard point of view, that’s probably the least obvious answer.
Your name is your name, and no piece of paper can grant it or take it away.
If I were to venture a guess, I’d say that a person’s name would be something like “$givenName $familyName”, such as “Harry Potter” or “Albus Dumbledore”. The givenName is the name your parents gave you when you were a baby. The family name is the name of your Noble House (“Malfoy”, “Potter”, etc.), or simply the last name which your parents share (“Granger”). This is the naming convention that (as per my guess) wizards and witches have been using since the time of Merlin, so it’s reasonable to assume that the creators of the Map imbued it with the same rules.
As to the question, “yes, but how does the Map compute the values of givenName and familyName for any specific person”, the answer is, “Magic”.
Also middle initials, apparently:
Ah, yes, good catch. Though we could probably count middle initials as part of the given name, since they are granted to the baby by its parents at the same time as the givenName… aren’t they ? I’m actually not entirely sure how middle initials work in Britain.
If the world of HPMOR is some sort of simulation, as you claim, then this is true and significant; your name exists as a fixed value that can be referenced by a program like the Map. But if the world of HPMOR is more like our own, then to say “your name is your name” is pretty empty; like most everything else, there is an explanation of why your name is your name. In our world, what makes it true that we bear the names we do is not that we all have own values for the variable $name. Rather, what makes it true is some other fact; one possibility (one that I don’t believe myself) is that what makes it true that my name is Alex is the fact that my birth certificate reads ‘Alex’.
So I think our disagreement arises from what we think the world of HPMOR is like.
I think these are two separate issues.
One issue is concerned with the wizards’ concept of names. The wizards who created the Map would seek to imbue it with whatever naming convention felt right to them.
The other issue is concerned with how the HP:MoR universe works, and which resources the Map can tap in order to implement its functionality.
These issues are somewhat related, but they aren’t identical. We could very easily envision a world where names are stored on birth certificates, and yet the wizards still believe that, even if Mr. Harry Potter goes through life calling himself “Mr. Spoo”, his name is still Harry Potter, because that’s what his parents, Mr. and Mrs. Potter, called him. On the other hand, we could envision a world where names are stored in some underlying data structure in the simulation, and yet the wizards believe that what a person calls himself is more important than whatever name parents gave him. Or we could envision some combination of the two.
That said, IMO no wizard would conceive of actually perusing the birth certificate database for anything; nor would he deliberately enchant a map to do anything of the sort. For all we know, wizards and witches don’t even have any birth certificates. It’s pretty likely that, even if they do have birth certificates, they don’t have any centralized databases that store them; we never seen any wizard use one, IIRC, neither in canon nor in MoR.
So, “how does the Map work ?” Well, it works the same way Harry’s Mokeskin Pouch works: by magic.
Other than the “external database” option, the only other sources of name information I can think of are:
The mind of the person being mapped
The mind of the person reading the map
A sort of consensus of how everyone in Hogwarts knows someone
I feel that picking someone’s name from their own mind seems the most elegant and consistent. It doesn’t handle babies (Before the parents choose a name, can a baby even be said to have one? Babies would have to be special-cased regardless), but it does allow arbitrary people to be mapped (multiple strangers being indistinguishable from each other seems like a serious flaw in a security system) and requires no external registry. On the one hand, it seems like interrogating the mind of every human is vastly more complicated than just looking up the name in a database, but to the kind of epistemology which would seem obvious to a 9th-century witch or wizard I can see it being “obvious”.
(And to respond to your question about Pettigrew in the great-grandparent, I would assume that the map skips over animals entirely, which would probably include animagi. This would tend to lend a slight amount of weight to my “the map displays your name as you know it” theory, as if the names came from how everyone else around you knew you there would be no reason not to include pets.)
If my theory is true, it raises an additional interesting question: Is it possible to obliviate yourself selectively so that you lose all knowledge of your own name? (Possibly storing the memories in a pensieve first so you can recover them later) And if so, is the map the only piece of the Hogwarts security system which might be impeded by this?
A further idea: Professor Quirrel is shown to take a very loose approach to identity and names (“Identity does not mean, to such as us, what it means to other people.”) Possibly Quirrelmort is the constant error, not because his name is wrong, but because he doesn’t have a name attached to his marker at all.
A large part of the plot of Prisoner of Azkaban hinges on the fact that Lupin noticed Pettigrew on the Map while he was in rat form.
In Quirrell’s case, he may be a powerful enough Occulumens to prevent the Map from reading his mind and so learning his name (if your theory is correct).
I’m not saying this is true. But I hope it is because it would be awesome.