# Gall peters projection — politically correct or incorrect? [closed]

Question: Why is the Gall Peters projection considered politically correct?

I've thought about this for some time, and to me, it seems to be more politically incorrect than correct. This is because the map distorts the landmasses in the Southern Hemisphere rather badly, even though it accurately depicts the size/area of the landmasses to its northern counterparts.

I need help with this. I've asked my friends, and they're confused too.

• This isn't really a world-building question at all. – jdunlop Aug 29 '17 at 6:13
• The Gall-Peters projection is an equal-area projection; it preserves areas undistorted, but distorts both angles and distances. The Mercator projection is a conformal projection; it preserves angles and small shapes undistorted, but distorts both distances and areas. A gnomonic projection preserves distances from a specific point undistorted but distorts all other distances in addition to angles and areas. Etc. etc. Each map projection has its uses; I don't know what political correctness is but it is certainly not an attribute of map projections. – AlexP Aug 29 '17 at 10:55
• xkcd.com/977 – user25818 Aug 29 '17 at 16:36

For most people who are not navigators, and for most purposes, area matters more than angles. Land area matters more than sea area, and largely uninhabited area does not matter much.

There is no "mathematically correct" projection.

Go to the equator. Move about 10000 km in a straight line along the equator. Turn 90 degrees and move about 10000 km in a straight line to the pole. Turn about 90 degrees and move about 10000 km in a straight line to your starting point. Turn 90 degrees to get to your original facing. A triangle with a sum of angles of 270 degrees. On a flat map either the lines or the angles must be distorted, or both, because a flat triangle has a sum of angles of 180 degrees.

So which distortion do you use?

Depends on your purpose. You get a choice of where and how the surface of the sphere gets distorted.

• It is common to accept a distortion at the North and South Poles. That is really dangerous when one thinks about Cold War military strategy, and about why Russia might feel encircled right now.
• One could say that it is no problem if Canada, Greenland, and Iceland get inflated on the map. Snow, ice, more snow, few people.
• It could be a problem if Central Europe appears inflated. They've already got the Prime Meridian, and now that, too. That could lead to excessive notions of their importance, and ignoring the sheer size of the rest of the world, especially equatorial regions.
• Distorting the southern hemisphere is seen as less of a problem. Few people live in Antarctica. South America and South Africa are relatively small landmasses projecting into the ocean. For Australia, the Greenland argument holds -- miles and miles of miles and miles.

Look at this map, Alaska appears bigger than India ...

• Maybe central Europe has a secret prime meridian... The public prime meridian passes through the western part of western Europe. – AlexP Aug 29 '17 at 10:47
• @AlexP, a slight simplification. The traditional projections are Europe-centric. And quite a lot of observatories, royal or otherwise, used to have their own meridians before the Brits won. Rome, Stockholm, ... – o.m. Aug 29 '17 at 17:52
• Putting Europe and Africa near the middle of a rectangular-ish world map has the advantage that the left and right edges of the map go mostly through the ocean; centering the Americas would make the left and right edges cut through continents, so it's not done (usually). The other good option is to center on China; the left and right edges would then pass through the Atlantic, the Pacific would be shown in its true shape and the Americas would be on the right side of the map. – AlexP Aug 29 '17 at 20:19
• @AlexP, that happens in my last link. – o.m. Aug 30 '17 at 5:08