How did the Greeks use building illusion?

Answer 1

It had to do with the apparent convergence of paralell lines- which can even be photographed taken at long focus down a railroad track- check for traffic first! The illusion is that the lines converge in the distance, the reality is they are at precise track gauge of 4 Foot 8 I/2 inches. this illusion, like many, can be photographed, there is something similar with columns on building sites, it is discussed in some detail in ione of the books on Atlantis by a man named, oddly Stacy-Judd , no relation to the Russian princess! Stacy_Judd had an architectural background, maybe in art school and explains how it worked- it was called entasis. read the book, that can explain it better than I, who twice went to summer school for math.

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Bit of tangle, that lot! The apparent effect of narrowing with distance is called "Perspective".

Entasis was used by the Ancient Greeks in their buildings, by thickening vertical columns very slightly in the middle. If a column is parallel it looks as if waisted-in. The entasis has to be calculated very carefully to avoid the reverse effect, which can end up looking very silly!.