"Scifi Writers Have No Sense Of Scale" is an observation that the scales given in speculative fiction are often nonsensical (Source).
Let's assume that these incongruities are not simply a mistake on the author's part but are accurate depictions of the fictional world itself. What could explain these departures from our own reality?
The scales given in the series A Song of Ice and Fire seem absurdly exaggerated (Source). These figures and the official map are used to estimate the size of the setting, the "Known World," which comes to roughly 89-104% the size of Earth (Source).
I strongly question the accuracy of the official map, which seems completely unreliable (Source). It's clearly a wildly inaccurate map created by medieval cartographers using substandard data and tools. Nonetheless, it is treated by Martin and fans alike as an accurate depiction of the story world: official and unofficial estimates of distances and travel times are based on that map.
If Westeros is analyzed from a demographic perspective, it makes no sense for it to be anywhere near the size of South America (Source). The demographics of Westeros are more homogeneous than any feudal empire in Earth's history. However, because of the previous calculations any attempt to reduce the size of Westeros to a realistic figure also reduces the planet's diameter by over half, making it denser than the densest known mega-Earth K2-56b.
There are other instances where the Known World displays impossible physical properties:
- The moon cannot be a satellite because it sits in a fixed position relative to the planet (Source). Assuming it sits at a Lagrange point then it should exert far weaker gravity, yet the tides operate at full strength.
- The years long winters work similar to miniature ice ages and are accompanied by standard seasons (Source). The Citadel estimates the length of these ice ages based on the length of the day (Source). The two statements cannot both be true unless there are two spells: one to create the ice ages and another to create the normal seasons.