Qi Men Dun Jia

Qi Men Dun Jia (奇門遁甲, "Mysterious Gates Hiding Jia") is one of the Three Supreme Arts (San Shi) of Chinese metaphysics alongside Liu Ren and Tai Yi.

Military history. Historically, the system was used for military strategy: tradition credits its application to the generals Zhuge Liang (third century) and Liu Bowen (fourteenth century).

Origin. Its presumed origin lies in the Warring States period (475–221 BCE), though mythological dating traces the system back to the Yellow Emperor, Huangdi.

Structure — Layers Superimposed on the Lo Shu Square

The system is built on the Lo Shu square (a 3×3 magic square with numbers 1–9) and comprises several superimposed layers:

• 9 palaces (宮)
• 8 gates (門) — each bearing a characteristic: Open, Rest, Life, Death, Fear, Injury, Scenery, Obstruction
• 9 stars (星)
• 8 deity-spirits (神)
• 10 heavenly stems (天干)
• 12 earthly branches (地支)

The Hidden Jia

The central element. "The hidden Jia": the first heavenly stem is concealed under one of six "harmonies", providing the key to decoding the diagram.

Applications

Practical applications span:

• Date selection (choosing auspicious times and directions)
• Strategic planning
• Business decisions
• Feng shui and divination

An enormous number of combinations. The system generates 1,080 base combinations (or 4,320 in the extended version), making it one of the most technically dense symbolic systems in the world.

Place in Errarium

The highest tier of the Chinese tradition. In Errarium, Qi Men Dun Jia (#57) represents the highest tier of the Chinese metaphysical tradition.

Analog — Feng Shui. Its closest relative by toolkit is Feng Shui (#51), which also employs the Lo Shu square and the concept of qi but works primarily with space.

A unique dual focus. Qi Men works with time and direction simultaneously, making it a uniquely navigational instrument among all methods on the platform.