TL; DR: if the sky were ground
(ʇɥǝ Mᴉupoʍ p.50)
For 75 years, the Mondrian painting “New York City I” (a grid of red, yellow, blue, and black linear adhesive tapes) was hung upside down. Research eventually proved that it should be shown the other way around. However, due to possible damage, the painting would continue …