The common SanHe approach in utilizing the 3 rings namely: -
1. Earth Ring – utilized to establish facing
2. Human Ring – utilized to evaluate embrace
3. Heaven Ring – utilized to evaluate water
Are rather incomplete or to a certain degree, inaccurate as in accordance to the 3 classics of YangGong.
The common understanding is to use the Earth Ring to establish sitting based on the concept of Pure Yin Pure Yang. This concept is commonly understood as “a Yang incoming dragon must match Yang water establishing a Yang Facing”. How to measure the Yang incoming dragon?
Landform wise, the classics say, “The Dragon has come a thousand miles, but look only at the EIGHT FEET arriving at the Head”. The term “feet” in Chinese is also means “ruler”. Here is where the common interpretations go so wrong, as in 8 feet means “distance of 8 feet”.
Assuming that the “distance of 8 feet” is correct, the 24 Earth Ring is used to determine its YinYang. The next obvious question is where does these YinYang originated? Beforehand, one must understand that there is such thing as the followings: -
1. The mutual relation between the opposite Trigram within the Early Heaven sequence. So for example, Qian and Kun mutually unobstructed Qi. Because Qian is Yang, therefore Kun is also Yang.
2. While Qian is Yang, Qian receives Jia, Kun receives Yi, so both Jia and Yi are also Yang. This is called the rule of NaJia (another mind boggling concept reserved for other discussion).
As a result, the Earth Ring has inconsistent YinYang Mountains, not because they are mistakenly assumed to be based on Pure Yin Pure Yang, but they are assigned based on the concepts of Early Heaven Gua and NaJia.
In application, a Qian incoming Dragon is Yang warranted to be matched with a Yang Facing.
Subsequently, if one look at the Earth ring which is also called 24 Mountains Correct Needle because it follows the magnetic “North”, only the sitting Branch mountains match its facing Branch mountains in accordance to Pure Yin Pure Yang principle while the other stems and trigrams are mismatched. Contradictions arise when for apparently no concrete reasons, it is forbidden to actually use the sitting Branch mountains for fear that: -
1. Qi is overly strong.
2. Branch Facing would risk being afflicted by annual TaiSui, PoSui and SanSha.
With such, how do we achieve the concept of Pure Yin Pure Yang by means of “a Yang incoming dragon must match Yang water establishing a Yang Facing”? Furthermore, this very novel idea contradicts one of the most fundamental indisputable doctrine, how can pure Yang or pure Yin ever grow ShengQi? As for the validity of SanHe method based on pure Yin pure Yang, your guess is better then mine…