That is, eight diviners with different orientations: Gan, Kun, Gen, Right, Kan, Li, Zhen and Xun. Geomantic omen calculates people's gossip attribute with the cycle of ternary Jiazi 180 years, and the gossip born every year is different according to the cycle from year to year. Among them, Gan, Kun, Gen and Dui are the four fortunes of the West, and Kan, Li, Zhen and Xun are the four fortunes of the East. The fourth ancestor of the West only lived in the fourth room of Gan, Kun, Gen and Dui, and the fourth ancestor of the East only lived in the fourth room of the East. Whenever there is confusion, there is a fierce disaster. "Twenty Books of Fuyuan in Yangzhai" said: "At the beginning of Gaijue, Tai Chi gave birth to two instruments, two instruments gave birth to four elephants, and four elephants gave birth to gossip. Therefore, dividing strangers into things is a two-meter theory, dividing strangers into things is a four-image theory, and dividing strangers into cadres, obstacles, roots, truth, training, reasoning, Kun and gossip is the natural principle of the avenue of heaven and earth. If Fuyuan (that is, the gossip attribute of birth year) is wrong, the four things in the East will repair the West, and the four things in the West will repair the East, and good luck will become fierce. Accordingly, people who live in different houses in different life palaces must pay attention to their own orientation, the orientation of doors, roads, wells, kitchen stoves, grinding, corral and water removal. If mixed together, it is unlucky. Zhao Jiufeng's "Three Essentials of Yang Zhai" said: "Gan, Kun, Gen and Dui are all four houses, and divination can't be met. If you put him in the house by mistake, the disaster of population injury will be serious. Kan, Li, Zhen and Xun are the only ones, but there are no other four in the West. He got married in one breath, and his descendants prospered. "