[coffeecat]

Everyone loves to mock the flat Earthers, but I believe the theory deserves more respect.

For the typical person, who roams around on some small patch of the Earth's surface, but who isn't launching rockets or traveling between continents, the flat earth theory is more useful than the spheroid earth theory. When you walk a short distance, your path's deviation from planar geometry due to the earth's global curvature is orders of magnitude smaller than the deviation due to local surface roughness, and hence the global curvature is irrelevant in practice. Let's say you walk 5km (about 3 miles); the difference between your path as predicted by the planar-earth theory versus the spherical earth theory is about one tenth of a millimeter. For 99% of what we do, invoking the spheroid Earth theory would be like using general relativity to model a baseball's trajectory in the presence of air resistance.

And if you happen to be far from the earth, on a length scale greater than about 10**9 km, then the point-earth theory is probably going to be the most useful model to you.

In short, it's all a matter of perspective. "Objective truth" isn't a thing; all that matters is how effective your model is at describing the properties that are relevant to you.

[krapp]

"When people thought the Earth was flat, they were wrong. When people thought the Earth was spherical, they were wrong. But if you think that thinking the Earth is spherical is just as wrong as thinking the Earth is flat, then your view is wronger than both of them put together." - Isaac Asimov