Onmyōdō (陰陽道) is a concept in Japan which used the ideoogy of Ying and Yang which originated in China.
Emperor Richū (400-406AD) is said to have died from a lack of harmony in the ‘elements of water and earth’ within him showing that the concept of Ying and Yang had arrived in Japan by the time of his reign.
Later, during the reign of Emperor Kōtoku (645–654AD) the Office of Ying and Yang Divination (Onmyōdō) was established and overseen by the Abe Clan and Kamo Clan.1 This sect held the concept of ‘shakuzetsu,‘ which was treated as the most auspicious day of the week, and occurred every six days, the Kanji used for this concept were the same used later for the Yokai called the Akashita.2
1. Martin, P. (1997) ”The Chrysanthemum Throne”. Gloucestershire: Sutton Publishing Limited.
2. Yoda, H. and Alt, M. (2016) “Japandemonium: Illustrated: The Yokai Encyclopaedia of Toriyama Sekien.”. New York: Dover Publications, Inc.
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