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In the Zi-Wu years, Shaoyin (Lesser Yin) governs the Heaven Qi; in the Chou-Wei years, Taiyin (Greater Yin) governs the Heaven Qi.
In the Yin-Shen years, Shaoyang (Lesser Yang) governs; in the Mao-You years, Yangming (Greater Yang) governs.
Chen-Xu years are paired with Taiyang (Greater Yang); Si-Hai years are inhabited by Jueyin (Terminal Yin).
The main Heaven Qi (fixed atmospheric influence) begins at the Yi position (the first Qi), and one proceeds sequentially to determine the others based on this order.
When advancing three steps, one reaches the position of the Heaven Qi; when advancing four steps, one reaches the beginning of the Guest Qi (changing atmospheric influence).
If it is a Zi-Wu year, Shaoyin (Lesser Yin) becomes the Heaven Qi.
Excluding the Heaven Qi's own position and counting to the third, Yangming (Greater Yang) becomes the Earth Qi (opposite position).
The fourth position, Taiyang (Greater Yang), is the initial Guest Qi, followed by Jueyin (Terminal Yin).
Subsequently, Shaoyin (Lesser Yin) begins from the Major Cold solar term, primarily governing the first half of the year.
Next is Taiyin (Greater Yin), then Shaoyang (Lesser Yang), ending with Yangming (Greater Yang). From after the Great Heat solar term, it governs the second half of the year. Each Qi lasts sixty days and eighty-seven and a half ke (ancient time units), distributed above the generating Qi, with the rest following the diagram of Main and Guest Qi.

Three Yin and Three Yang constitute the manifestations (Biao) of the Six Qi of Heaven; Metal, Wood, Water, Fire, and Earth constitute the roots (Ben) of the Five Elements of Earth (corresponding to Growth, Transformation, Harvest, Storage, and Birth). Taiyin Damp Earth and Shaoyang Ministerial Fire have identical Root and Manifestation attributes. As for Shaoyin Sovereign Fire and Taiyang Cold Water, their Yin-Yang and Cold-Heat attributes differ mutually. Why? Because Sovereign Fire governs the Zi-Wu years. Wu represents the position where One Yin begins to generate. Fire is inherently hot, but its Qi occurs at the beginning of Yin generation; thus, Sovereign Fire belongs to Shaoyin (Lesser Yin). Water resides in the Northern Zi position. Zi represents the position where One Yang begins to generate. Water is inherently cold, but its Qi occurs at the beginning of Yang generation; thus, Cold Water belongs to Taiyang (Greater Yang). This is why the Roots and Manifestations of Water and Fire differ. Earth occupies the Wei position in the South-West dimension, corresponding to the months of Late Summer. Wei follows Wu and is Yin; therefore, Earth is called Taiyin (Greater Yin). Ministerial Fire governs the Yin year. Yin follows Chou and is Yang; therefore, Ministerial Fire is called Shaoyang (Lesser Yang). Wood is located in the East Zhen trigram and governs the Liver in humans. Although Yang in nature, it resides below the diaphragm, in a Yin position; thus, it belongs to Jueyin (Terminal Yin). Metal is in the West Dui trigram and governs the Lungs in humans. Although an Yin organ, it resides above the diaphragm, in a Yang position; thus, it belongs to Yangming (Greater Yang). The Classics state: "Shaoyang and Taiyin are treated according to the Root; Shaoyin and Taiyang are treated according to the Manifestation; Yangming and Jueyin do not follow the Root or Manifestation but are treated according to the Middle Qi." The Middle Qi of Yangming is Taiyin (Taiyin and Yangming are exterior-interior pairs and harmonize). The Middle Qi of Jueyin is Shaoyang (Jueyin and Shaoyang are exterior-interior pairs and harmonize).