What do you mean, the walls are covered with dirt?

Ancient astrologers believed that the twelve days in astronomy symbolized twelve situations of personnel establishment, separation, fullness, equality, determination, persistence, breaking, danger, success, closing, opening and closing respectively. "Huainanzi Astronomical Training": "Yin is the construction, Mao is the division, Chen is the fullness, Si is the harmony, and the Lord is the longevity; Noon is fixed, not used for holding, the main trap; Shen is breaking, the main balance; Unitary is dangerous, the main ladle; In order to succeed, the Lord is less virtuous; Hai is the harvest, the main virtue; The son opens, and the Lord is too old; Ugly and closed, the Lord is too cloudy.