Living in the Middle Kingdom—by Kwong Hing Yen (江慶人)
Maps have been valuable tools for millennia, despite most of them,
especially world maps, being quite badly distorted. The fundamental
challenge of plotting the surface of a sphere onto a flat sheet of paper
forces maps to make compromises when depicting angles, sizes, and
distances—if the earth were flat, things would be much easier. For
example, the historically popular Mercator projection provides true
angles for seafarers, meaning you can read an angle off the map and use
the same angle on the ship’s compass (compensating for the discrepancy
between geographic and magnetic north). The price to pay for this
convenient property, which avoids distorting angles, is area distortion:
the further away countries are from the equator, the larger they
appear on the map. That’s why Africa looks
disproportionately small on such maps,1 a trade-off that might be acceptable when navigating
by boat: misestimating the distance is likely a lesser problem than
heading into the wrong direction.
Plotting the surface of a sphere also presents the challenge of deciding
where the “middle” is. Most world maps conveniently position Europe in
the center, supported by 0 degree longitude (the prime meridian) going through Greenwich, England. This depiction results in Asia being ...
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