Talking about Ti and Yong, we must not forget that Xian Tian (Ba Gua) is Ti while Hou Tian (Ba Gua) is Yong 先天為體，後天為用.
There is also a saying that mountain governs people while water governs wealth 山管人丁， 水管財祿. Now, since for Heaven qi, we get the direction of Zheng Shen by locating the golden dragon #5 in the Heaven Chart, while Ling Shen is the direction opposite that of Zheng Shen, then each of the nine periods has a specified direction for Zheng Shen and Ling Shen. Period 5 is divided into 10 years following Period 4 and the second 10 years following Period 6.
On the other hand, for Earth qi, we have a broader sense of the terms Zheng Shen and Ling Shen. There is no need to fly the star. The Xian Tian Ba Gua with Luo Shu numbers explain it well.
The terms Zheng Shen and Ling Shen are actually used in different ways by different schools.
What Tan Yang Wu teaches is:
For the Upper Cycle, 1234 represent Ling Shen while 6789 represent Zheng Shen.
For the Lower Cycle, 6789 represent Ling Shen while 1234 represent Zheng Shen.
For Xuan Kong Da Gua, the terms are defined just in the opposite way.
For the Upper Cycle, 1234 represent Zhen Shen while 6789 represent Ling Shen.
For the Lower Cycle, 6789 represent Zhen Shen while 1234 represent Ling Shen.
In the next episode, I will explain how each is to be used.
The funniest thing is that some people teach that during the Lower Cycle today, water should be in the N, SW, E and SE while mountain must be in the NW, W, NE and S. If water is misplaced in the directions where there should be mountain, then it will bring misfortune. This is the result of not having a good understanding of Body and Application, Xian Tian and Hou Tian.