Back in the early 90's (in the US) I had a friend who was a college student from China. In the common area of her dorm there was a huge wall-size Rand-McNally map of the world. We were looking it over.
"There's China" I said. "And there's Taiwan."
"You know Taiwan is really not that big." she said.
"What do you mean?"
"Map makers show it larger than it really is in order to exaggerate its importance."
I was a little weirded out by that idea. This girl was pretty intelligent, she seemed to know some math and logical thinking. She was in the process of becoming a CPA.
For better or worse I responded with practical analysis: "How would that even work? You and I could go buy maps right now for navigating ships and airplanes, those would have to be accurate in order to function. We could compare them to this one and if they are noticeably different we could complain and the company that made the map would lose face. Why would Rand-McNally give a shit about the political importance of Taiwan anyway, enough to risk their own credibility?"
"They just do. All map makers do this." She would not be convinced.
those would have to be accurate in order to function
The most common form of map, Mercator projection, greatly distorts the area of land around the equator, and makes northernly (& southerly) lands appear much larger. It makes Canada, Greenland, Alaska, et al. appear quite large compared to Africa & South America. But those areas are much larger.
The Mercator projection isn't a good example of a map in which visual distortion and a lack of navigational utility go hand in hand.
Indeed, the hole point of the projection was to make navigation easier by allowing rhumb lines (the shortest distances between two points on a curved surface) to be charted as perfectly straight lines on a two-dimensional map. From these lines of constant bearing, mariners could work out the precise - and constant - angle they should maintain in relation to the pole star in order to get from one point to another.
Without a reliable method for establishing longitude at sea, 17th Century navigators could never be exactly sure how far along their courses they were, but at least they could know that they were heading in the right direction. Given the level of uncertainty involved in these enterprises, this one piece of (relatively) hard and verifiable data was extraordinarily important, making the accuracy of the projection, and the mathematically - if not visually - correct placement of shorelines within it especially important.
Unfortunately, the iconic value of the Mercator projection has vastly outlived its utility - or at least, the common awareness of the once formidable navigational problems it addressed. Far from seeing it as a brilliant technical solution, it is often seen through a purely political filter that views its strengths as weaknesses, while completely missing the map's actual intent.
Let's not get mixed up about what the projection did and didn't do. As you point out, the importance of rhumb lines comes not from the fact that the thing they keep constant -- the bearing (with respect to north/south) -- was something that could actually be measured.
Rhumb lines are not, however, the shortest distance between two points on a sphere. Those would be great circles. In particular, note that along a rhumb line one can never reach the north or south pole. Indeed, rhumb lines are dependent on your choice of poles, which the actual shortest course clearly cannot be!
Argh. Misnegation from earlier version. "As you point out, the importance of rhumb lines comes from the fact that..." -- there shouldnt' be a not there.
You are (it seems intentionally) ignoring the point that Mercator's area distortion doesn't dangerously mislead in navigation, quite the contrary. Or, if that isn't true, please name some cases where navigators were messed up because they thought Greenland looked bigger than it was in area.
Unless you use a globe, every projection onto a flat rectangular surface distorts.
Now how does that make more plausible the claim that world map makers are inflating the area of Taiwan on purpose?
Really? Seemed like he was simply pointing out an error on my part. Don't see where Taiwan enters that at all.
More to the point, there's a big difference between distorting scale in a way that's mathematically consistent throughout the projection (i.e. one in which you preserve shape or position at scale's expense), and simply fudging the scale in a particular spot.
Really? I think you meant rhumb lines. :) They're both important, just for different reasons; and it's rhumb lines that are easily visible on a Mercator projection and that were so useful for navigation.
Mercator distortion has nothing to do with the anecdote in the parent post. There the allegation was of deliberate inaccuracy, which renders a map non-functional for most purposes.
All 2D map projections produce either distortion or discontinuity. Neither of these affects a map's functionality in the way that outright inaccuracy does.
Oh yes, I agree that this is an example of purely the geometry, not a political attempt. But I know people who , upon seeing the distortion, were surprised at how many maps were "wrong". This shows that you can't rely on the market to weed out inaccurate maps. After all, a map that had the south at the top (rather than the bottom) would be viewed as "wrong" and would be penalized with poor sales.
The idea that the market will always produce the best map is not true.
As an aside, I have often wondered at the way North=up became, and remains, completely universal. An upside-down globe "looks" as wrong to me as an upside-down portrait. Obviously there's no reason this must be so; it's nothing more than familiarity with the shapes of the continents from a particular perspective.
Some day, I'd like to have a globe or a big mercator-type map with South at the top (i.e. with the written labels upside-down from normal), and see how long it would take to become accustomed to it.
"you can't rely on the market to weed out inaccurate maps" is a misleading statement, particularly in the context where people are contending that the size of Taiwan has intentionally been inflated worldwide for political reasons.
THAT kind of inaccuracy bears almost no resemblance to gripes which emerge about the tradeoffs in 2d map projections regarding inevitable (as opposed to highly arbitrary, political) shape and area distortions.
Maps which have south at the top ARE sold and do just fine in the Southern Hemisphere.
The point actually remains that the market has not rewarded any maps which have the kind of distortions which would be required to specifically and artificially inflate the size of Taiwan relative to China, without much affecting anything else.
There are a bunch of parallel conversations spawned from this 2 year old blog post. For reference, here's the area the author talked about in current google maps:
The locations are all still off and they're consistently off by an offset throughout Shanghai. There might be some deliberate dishonesty by map makers in China, but I don't think this is evidence of it - I think this is just an inaccurate projection. If you want to make bad maps to confuse people - first, that's probably pretty impossible with current information systems, even in China, and second, this would be a really bad attempt at it.
Yes I was familiar with that at the time, but I don't recall if it was mentioned in our particular discussion. In any case, Taiwan is relatively far South in its region so the projection effect would tend to be reduced. It would actually have the effect of making mainland China look larger.
Are you suggesting that in this case the blogger is similarly misinformed or deluded?
I don't think it's unreasonable to think that China is manipulating its map data, particularly when other people here in the mapping industry have already said this is well known in their field.
I think the gp is telling an anecdote that is an interesting example of the difficulty that exists in China for certain things, and in no way states that the blogger is misinformed or deluded.
An interesting anecdote from my side, though not necessarily map-related. But in the same theme as gp. This summer, I was volunteering teaching English to rural kids in China. One of the kids kept writing this big message on blackboards and stuff that Osama bin Laden was still alive. One of the local volunteers read what he was writing and was upset at him for fooling around so much. Later, I asked her what's up, and she told me what he was writing.
WTF.
So in the team meeting later that night, I talk with my fellow volunteers about this, and wonder if I have some kind of crazy kid on my hands. Then the Chinese volunteers told me not to worry about it, he's just writing stuff. I'm like, "What do you mean, how do you know?" Then they started talking about how people distrust the government these days, are unhappy, etc. I'm like, "What the heck does that have to do with anything?"
Turns out that all over the Chinese web, this was a really popular meme where Chinese youth displayed their sarcasm at anything the government said. Even things that they knew to be true could not be true because the government said it. It was only a meme, much like the Hitler videos we see on Youtube.
Scared me for a day.
But suffice it to say, people in China aren't so trusting of what their nation says as before. Living here, I hear it from my colleagues and friends every day. That being said, there's very little right now that they can do to voice their opinion because it's still a touchy atmosphere.
Seems more likely that Chinese maps make Taiwan smaller, and when people in China point to the differences between locally made maps and foreign maps, they are told that foreign map makers are playing some sort of anti-China political game.
Or, people have it ingrained in them that Taiwan is small, and they all know that Chinese map-makers are politically motivated, so they assume that all map-makers are equally politically motivated.
My take on it at the time was that she had been convinced at some point that all Western maps were made that way for political reasons. I didn't get the sense that she was reacting to the size on the map we were perceiving.
You knew her disposition. (You were her friend). What was the goal of that comment, to incent a fruitless political discussion?
Edit: Whoa there. Why the downvotes? I am genuinely curious why the parent decided it was a good idea to stoke that discussion. I have friends whose political views are far from mine, and there are just DMZ topics that I don't dare bring up. For example, a discussion about the Federal Reserve and Operation Twist would be fruitless with my Libertarian friends, who just have a different opinion on that, which I believe is irreconcilable. I would say that's the same situation with Taiwan-strait politics.
You say that, but you've clearly never gone up against an adversary with a complete lack of boundaries around what they'll do to achieve their political goals. Politics often manipulates facts.
There are a lot of topics I'd love to say aren't open to political debate, because I personally consider them axioms of basic sanity, but the existence of people who disagree unfortunately leaves the debate open.
Comments
Back in the early 90's (in the US) I had a friend who was a college student from China. In the common area of her dorm there was a huge wall-size Rand-McNally map of the world. We were looking it over.
"There's China" I said. "And there's Taiwan."
"You know Taiwan is really not that big." she said.
"What do you mean?"
"Map makers show it larger than it really is in order to exaggerate its importance."
I was a little weirded out by that idea. This girl was pretty intelligent, she seemed to know some math and logical thinking. She was in the process of becoming a CPA.
For better or worse I responded with practical analysis: "How would that even work? You and I could go buy maps right now for navigating ships and airplanes, those would have to be accurate in order to function. We could compare them to this one and if they are noticeably different we could complain and the company that made the map would lose face. Why would Rand-McNally give a shit about the political importance of Taiwan anyway, enough to risk their own credibility?"
"They just do. All map makers do this." She would not be convinced.
those would have to be accurate in order to function
The most common form of map, Mercator projection, greatly distorts the area of land around the equator, and makes northernly (& southerly) lands appear much larger. It makes Canada, Greenland, Alaska, et al. appear quite large compared to Africa & South America. But those areas are much larger.
http://en.wikipedia.org/wiki/Mercator_projection#Uses
The Mercator projection isn't a good example of a map in which visual distortion and a lack of navigational utility go hand in hand.
Indeed, the hole point of the projection was to make navigation easier by allowing rhumb lines (the shortest distances between two points on a curved surface) to be charted as perfectly straight lines on a two-dimensional map. From these lines of constant bearing, mariners could work out the precise - and constant - angle they should maintain in relation to the pole star in order to get from one point to another.
Without a reliable method for establishing longitude at sea, 17th Century navigators could never be exactly sure how far along their courses they were, but at least they could know that they were heading in the right direction. Given the level of uncertainty involved in these enterprises, this one piece of (relatively) hard and verifiable data was extraordinarily important, making the accuracy of the projection, and the mathematically - if not visually - correct placement of shorelines within it especially important.
Unfortunately, the iconic value of the Mercator projection has vastly outlived its utility - or at least, the common awareness of the once formidable navigational problems it addressed. Far from seeing it as a brilliant technical solution, it is often seen through a purely political filter that views its strengths as weaknesses, while completely missing the map's actual intent.
Let's not get mixed up about what the projection did and didn't do. As you point out, the importance of rhumb lines comes not from the fact that the thing they keep constant -- the bearing (with respect to north/south) -- was something that could actually be measured.
Rhumb lines are not, however, the shortest distance between two points on a sphere. Those would be great circles. In particular, note that along a rhumb line one can never reach the north or south pole. Indeed, rhumb lines are dependent on your choice of poles, which the actual shortest course clearly cannot be!
Argh. Misnegation from earlier version. "As you point out, the importance of rhumb lines comes from the fact that..." -- there shouldnt' be a not there.
You are (it seems intentionally) ignoring the point that Mercator's area distortion doesn't dangerously mislead in navigation, quite the contrary. Or, if that isn't true, please name some cases where navigators were messed up because they thought Greenland looked bigger than it was in area.
Unless you use a globe, every projection onto a flat rectangular surface distorts.
Now how does that make more plausible the claim that world map makers are inflating the area of Taiwan on purpose?
Really? Seemed like he was simply pointing out an error on my part. Don't see where Taiwan enters that at all.
More to the point, there's a big difference between distorting scale in a way that's mathematically consistent throughout the projection (i.e. one in which you preserve shape or position at scale's expense), and simply fudging the scale in a particular spot.
Indeed, Sniffnoy - thanks for sorting out my terminology. Great circles is exactly what I meant.
Really? I think you meant rhumb lines. :) They're both important, just for different reasons; and it's rhumb lines that are easily visible on a Mercator projection and that were so useful for navigation.
Mercator distortion has nothing to do with the anecdote in the parent post. There the allegation was of deliberate inaccuracy, which renders a map non-functional for most purposes.
All 2D map projections produce either distortion or discontinuity. Neither of these affects a map's functionality in the way that outright inaccuracy does.
Oh yes, I agree that this is an example of purely the geometry, not a political attempt. But I know people who , upon seeing the distortion, were surprised at how many maps were "wrong". This shows that you can't rely on the market to weed out inaccurate maps. After all, a map that had the south at the top (rather than the bottom) would be viewed as "wrong" and would be penalized with poor sales.
The idea that the market will always produce the best map is not true.
I see what you're saying. I agree.
As an aside, I have often wondered at the way North=up became, and remains, completely universal. An upside-down globe "looks" as wrong to me as an upside-down portrait. Obviously there's no reason this must be so; it's nothing more than familiarity with the shapes of the continents from a particular perspective.
Some day, I'd like to have a globe or a big mercator-type map with South at the top (i.e. with the written labels upside-down from normal), and see how long it would take to become accustomed to it.
In early times, east was up and north to the right. Apparently an Australian group made a south is up map
Isn't that backwards? If east were up, north would be to the left. Unless you're making a celestial map.
Yes, you're right, my mistake. I was thinking of an old map I saw that had west up and north right.
"you can't rely on the market to weed out inaccurate maps" is a misleading statement, particularly in the context where people are contending that the size of Taiwan has intentionally been inflated worldwide for political reasons.
THAT kind of inaccuracy bears almost no resemblance to gripes which emerge about the tradeoffs in 2d map projections regarding inevitable (as opposed to highly arbitrary, political) shape and area distortions.
Maps which have south at the top ARE sold and do just fine in the Southern Hemisphere.
The point actually remains that the market has not rewarded any maps which have the kind of distortions which would be required to specifically and artificially inflate the size of Taiwan relative to China, without much affecting anything else.
There are a bunch of parallel conversations spawned from this 2 year old blog post. For reference, here's the area the author talked about in current google maps:
http://maps.google.com/maps?q=Huashan+Road,+Shanghai,+China&...
The locations are all still off and they're consistently off by an offset throughout Shanghai. There might be some deliberate dishonesty by map makers in China, but I don't think this is evidence of it - I think this is just an inaccurate projection. If you want to make bad maps to confuse people - first, that's probably pretty impossible with current information systems, even in China, and second, this would be a really bad attempt at it.
Yes I was familiar with that at the time, but I don't recall if it was mentioned in our particular discussion. In any case, Taiwan is relatively far South in its region so the projection effect would tend to be reduced. It would actually have the effect of making mainland China look larger.
Yes, the mercator projection is not at play here, but I'm pointing out how you can sell a 'wrong' map and not be commercially penalized.
Apparently Britain is also 'bigger' than it should be (it's really far smaller than France) on many maps, purely because the maps were made by the UK:
http://noisydecentgraphics.typepad.com/design/2008/07/this-i...
Are you suggesting that in this case the blogger is similarly misinformed or deluded?
I don't think it's unreasonable to think that China is manipulating its map data, particularly when other people here in the mapping industry have already said this is well known in their field.
I think the gp is telling an anecdote that is an interesting example of the difficulty that exists in China for certain things, and in no way states that the blogger is misinformed or deluded.
An interesting anecdote from my side, though not necessarily map-related. But in the same theme as gp. This summer, I was volunteering teaching English to rural kids in China. One of the kids kept writing this big message on blackboards and stuff that Osama bin Laden was still alive. One of the local volunteers read what he was writing and was upset at him for fooling around so much. Later, I asked her what's up, and she told me what he was writing.
WTF.
So in the team meeting later that night, I talk with my fellow volunteers about this, and wonder if I have some kind of crazy kid on my hands. Then the Chinese volunteers told me not to worry about it, he's just writing stuff. I'm like, "What do you mean, how do you know?" Then they started talking about how people distrust the government these days, are unhappy, etc. I'm like, "What the heck does that have to do with anything?"
Turns out that all over the Chinese web, this was a really popular meme where Chinese youth displayed their sarcasm at anything the government said. Even things that they knew to be true could not be true because the government said it. It was only a meme, much like the Hitler videos we see on Youtube.
Scared me for a day.
But suffice it to say, people in China aren't so trusting of what their nation says as before. Living here, I hear it from my colleagues and friends every day. That being said, there's very little right now that they can do to voice their opinion because it's still a touchy atmosphere.
This lady is very informative. http://www.ted.com/talks/lang/eng/yang_lan.html
Seems more likely that Chinese maps make Taiwan smaller, and when people in China point to the differences between locally made maps and foreign maps, they are told that foreign map makers are playing some sort of anti-China political game.
Or, people have it ingrained in them that Taiwan is small, and they all know that Chinese map-makers are politically motivated, so they assume that all map-makers are equally politically motivated.
My take on it at the time was that she had been convinced at some point that all Western maps were made that way for political reasons. I didn't get the sense that she was reacting to the size on the map we were perceiving.
Are you suggesting that in this case the blogger is similarly misinformed or deluded?
No.
> "There's China" I said. "And there's Taiwan."
You knew her disposition. (You were her friend). What was the goal of that comment, to incent a fruitless political discussion?
Edit: Whoa there. Why the downvotes? I am genuinely curious why the parent decided it was a good idea to stoke that discussion. I have friends whose political views are far from mine, and there are just DMZ topics that I don't dare bring up. For example, a discussion about the Federal Reserve and Operation Twist would be fruitless with my Libertarian friends, who just have a different opinion on that, which I believe is irreconcilable. I would say that's the same situation with Taiwan-strait politics.
My sense was she thought she was giving me a fact about geography I didn't know, as simple as that.
Later, she, another friend from China, and I had a more in-depth discussion about Taiwan. It was really interesting to get that perspective.
P.S. I have no idea why you're being downvoted either.
Facts as concrete as physical dimensions are not really open to political debate.
You say that, but you've clearly never gone up against an adversary with a complete lack of boundaries around what they'll do to achieve their political goals. Politics often manipulates facts.
There are a lot of topics I'd love to say aren't open to political debate, because I personally consider them axioms of basic sanity, but the existence of people who disagree unfortunately leaves the debate open.