Hetuluoshu

Rivers paint, Luo writes, and saints write. "This saint is Fuxi, the ancestor of human culture. Legend has it that in Fu, a dragon horse appeared from the Yellow River, carrying a "river map"; A turtle appeared from Luoshui, carrying "Luoshu". Fuxi drew eight diagrams according to this kind of "picture" and "book". Later, Zhou Wenwang studied the written king eight diagrams and sixty-four hexagrams according to Fuxi's eight diagrams, and wrote them into eight diagrams respectively.

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Luoyang, Henan