Eight is a considered the luckiest number is China because of its resemblance to 发 fa, meaning ‚prosperity‘. The octagonal shape goes back to the ancient 易经 Yi Jing, the ‚book of changes‘, often referred to as ‚I Ching‘. There, the 八卦 bagua (‚eight trigrams‘) form an octagon, used for divination. The bagua lu 八卦炉 (‚bagua furnace‘) was used by alchemist to create pills of immortality.
四面八方 si mian ba fang is a common saying meaning all directions of the earth, so everywhere.
An octagon is an important shape in Fengshui to ward off negative energy. This is why a lot of buildings in Asia have an octagonal foundation. There is even the rumor that the Singapore One-Dollar-coin is in the shape of a bagua so that there is protection in every household.
Get yourself some ‚Teapot Shapes II‘ postcards!
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