The underlying principle of the major wandering GUA, lies on the notion of the term wandering. From the original GUA, changing of the Yao took place at the based Yao. This changes is also known as flipping from Yin to Yang and vice versa. The chart below shows what that has been known on the 4 good stars and 4 bad stars.
Why 4 good and 4 bad? What is the basis of determining that the 9 stars must have Tang, Ju, Wu and Fu to be the goodies and Lien, Po, Wen, Lu to be the baddies?
Auspiciousness is measured by the relationship of mutual production “xiangsheng” whereas inauspiciousness is measured by mutual control or “xiangke”. Compound the rest we had 64 permutations with halves are good and halves are bad. This shows that the Ming Gua must matched the compatible House Gua. This also denotes that the LH Gua correlates with the Loshu numbers providing the Qi to a person’s Life Gua.
The most guarded principles that auspiciousness always revealed itself as 5 with its own multiplicity. The 2 slices comes from 5. The 5 is the central of the Hetu, the basis of the EH 8 Tri grams. 8, 3, 2, 7 forms the Eastern arm whereas 9,6,1,4 forms the Western arm of the Hetu. The degree of auspiciousness depend on the proximity of the number in relation to this arm of the Hetu, meaning nearer better, as in 3-8, 2-7, 6-9, 1-4 and so on.
These are the essense...
Ar. David Yek Tak Wai