Micheal wrote:
DE, the 'map', see above, is a social obsevation/statement, not a true map.
It is a purposeful distortion, a technique frequently used in marketing and social commentary, used to make a point.
Your earlier statements indicated that you did not know the picture or understand the purpose of it. Khross was commenting on that and that you had appeared to comment without knowing the subject matter. While the Professor can be a bit annoying at times, the comment was more along the lines of familiarize yourself with the material referenced than go back to school.
Chill dude, you are taking offense where none was intended.
Which is why I mentioned it
as an aside. Things like that aren't maps. They're pictures; they may resemble maps, but they are not maps. The "New Yorker" cover he references illustrates this; it is a picture of how a stereotypical New Yorker sees the world but it is not a map at all; it cannot be used to go from any point to any other with any remotely useful degree of accuracy.
An
actual map is a drawing that allows you to reach one point from another. In the simplest form, such as a "strip map", it's simply a route, usually not to scale, with text references telling the follower distances and landmarks. It can only be used to get to one end point or the other or to a point in between. "X marks the spot" for example; you must start at the boulder at the southern point of the island to find "X".
As maps get more complex we have localized maps which are (usually) scale drawings of features on the ground, and can be used to get to any point within the confines of the map. At this level, scale is useful but not strictly necessary; for example if you go to Cedar Point you can get around with the not-to-scale map in the brochure because there are always prominent landmarks available.
Once a map gets much bigger than a small town, however, scale starts to become important, and moreover, the curvature of the Earth starts to affect things. In order to make such maps, a model of the surface of the Earth, known as a sphereoid, is needed. This is then used to create a datum, or coordinate system. The most common modern system is WGS 84.
The problem, however, is that no one has ever created a totally accurate sphereoid of the Earth, mainly because it isn't a totally uniform, symmetrical sphereoid. This was more of a problem before the space age because a lot more guesswork was nvolved in any given sphereoid. This resulted in datums such as the Berlin Datum or Tokyo Datum and others from the late 19th and early 20th century which were very good close to their "0" point; ofen better than worldwide datums, but deteriorated more rapidly around the world. In fact, if you were to go to, say, the coordinates of the State House of Texas, in downtown Austin, by using a Tokyo datum map from pre-WWII, you would find yourself roughly a kilometer from the actual State house.
Satellites have allowed us to model the surface of the Earth far more precisely, although still not perfectly. Nevertheless this accuracy allows us to narrow accuracy down to within 1 meter using GPS under optimal condition.
This is why maps made in different locations will look a bit different. They're using different datums; in fact you'l even see differences between local maps such as those made based on the North American Datum 1927 and those based on NAD 1983. The earlier one was based on the Clarke Ellipsoid of 1866, the latter on the GRS 80 ellipsoid. The former was created based on a manual survery of the entire continent, the latter incorporated far more satellite information. If you were to compare a map based on the 1927 datum to a Japanese map from the same general period based on the Tokyo datum you would find differences, and you would find each system to be most accurate closest to its 0 point; in these examples Meade's Ranch in Kansas, and of course, Tokyo.
So yes, there will be different maps in different places, but not because of the way people think; because unless they're using a common datum, mathematical differences are inevitable. The professor is evidently not aware of this; what he's descrbing as "maps" in his analogy are not maps at all, but pictures just as the "New Yorker" cover is a picture.
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