Ancient Chinese numerology, particularly the cosmic boxes or magic squares, which date back over 2000 years B.C. have been used to explain all manner of phenomenon. Abdominal acupuncture theory also uses the ancient magic number boxes of the He Tou and the Lou Shu which are said to predate Yin-Yang, 5 elements (or 5 phases), and many other traditional Chinese medicine (TCM) theories (Yang-Li, 1998, p.6).
Both the He Tu and the Lou Shu cosmic boxes were ruminated upon by many of the great masters over time. From their analysis came various new theories, including the Ba Gua, which were discussed at length in such masterpieces as the Ling Shu and the I Ching (Yi Ching).
From these magic number boxes the early and later heaven Ba Gua formations arose. The later heaven Ba Gua is used to formulate the abdominal Ba Gua hologram.