先天卦配洛書之數 Pre-Trigrams x LUO-SHU

啓蒙附論曰洛書九數虚中五以配八卦陽上隂下故九為乾一為坤因自九而逆數之震八坎七艮六乾生三陽也又自一而順數之巽二離三兌四坤生三隂也以八數與八卦相配而先天之位合矣

按術家以乾配九坤配一離配三坎配七其數奇故為陽兌配四震配八巽配二艮配六其數偶故為隂

The Qimeng Fulu (Supplementary Commentary on Enlightenment) _ctext states:

In LUO-SHU

• There are nine numbers with 5 at the center, used to correspond to the 8 Trigrams:
• ⚊_YANG is above, and ⚋_YIN is below, thus 9 corresponds to ☰_HEAVEN and 1 corresponds to ☷_EARTH.
• Counting backward from 9: 8 corresponds to ☳_THUNDER, 7 corresponds to ☵_WATER, 6 corresponds to ☶_MOUNTAIN, ☰_HEAVEN generates three ⚊_YANG Trigrams
• Counting forward from 1: 2 corresponds to ☴_WIND, 3 corresponds to ☲_FIRE, 4 corresponds to ☱_LAKE, ☷_EARTH generates three ⚋_YIN Trigrams
• Through these eight numbers matching the eight Trigrams, the Pre-Natal positions are thus harmonized.