Yin–Yang: Tied to Sun and Moon

The Yellow Emperor said: I have heard that Heaven is yang, Earth is yin, the Sun is yang, and the Moon is yin. What is the relationship between these and the human body? Qi Bo replied: The area above the waist corresponds to Heaven, and the area below the waist corresponds to Earth. Thus, Heaven is yang and Earth is yin. Therefore, the twelve channels of the foot correspond to the twelve months; the moon is born from water, so what is below belongs to yin. The ten fingers of the hand correspond to the ten days; the sun governs fire, so what is above belongs to yang.

The Yellow Emperor said: How do they correspond with the channels? Qi Bo replied: Yin is the first month, when yang qi first arises, and governs the shaoyang channel of the left foot. Wei is the sixth month and governs the shaoyang channel of the right foot. Mao is the second month and governs the taiyang channel of the left foot. Wu is the fifth month and governs the taiyang channel of the right foot. Chen is the third month and governs the yangming channel of the left foot. Si is the fourth month and governs the yangming channel of the right foot. These are the two yangs meeting in the front, hence the name yangming. Shen is the seventh month, when yin qi first arises, and governs the shaoyin channel of the right foot. Chou is the twelfth month and governs the shaoyin channel of the left foot. You is the eighth month and governs the taiyin channel of the right foot. Zi is the eleventh month and governs the taiyin channel of the left foot. Xu is the ninth month and governs the jueyin channel of the right foot. Hai is the tenth month and governs the jueyin channel of the left foot. These are the two yins meeting and exhausting, hence the name jueyin.

Jia governs the shaoyang channel of the left hand; Ji governs the shaoyang channel of the right hand. Yi governs the taiyang channel of the left hand; Wu governs the taiyang channel of the right hand. Bing governs the yangming channel of the left hand; Ding governs the yangming channel of the right hand. These are the two fires combined, hence the name yangming. Geng governs the shaoyin channel of the right hand; Gui governs the shaoyin channel of the left hand. Xin governs the taiyin channel of the right hand; Ren governs the taiyin channel of the left hand.

Thus, the yang channels of the foot are the lesser yang within yin; the yin channels of the foot are the greater yin within yin. The yang channels of the hand are the greater yang within yang; the yin channels of the hand are the lesser yin within yang. The area above the waist belongs to yang, and the area below the waist belongs to yin. Regarding the five viscera: the heart is the greater yang within yang, the lung is the lesser yin within yin, the liver is the lesser yang within yin, the spleen is the utmost yin within yin, and the kidney is the greater yin within yin.

The Yellow Emperor said: How should treatment be applied based on these principles? Qi Bo replied: In the first, second, and third months, the human body's yang qi is on the left side; do not needle the yang channels of the left foot. In the fourth, fifth, and sixth months, the human body's yang qi is on the right side; do not needle the yang channels of the right foot. In the seventh, eighth, and ninth months, the human body's yin qi is on the right side; do not needle the yin channels of the right foot. In the tenth, eleventh, and twelfth months, the human body's yin qi is on the left side; do not needle the yin channels of the left foot.

The Yellow Emperor said: Among the five phases, the east corresponds to jia and yi wood and governs the spring season. Spring is associated with the color green, governs the liver, and the liver is the foot jueyin channel. Yet now jia is paired with the shaoyang channel of the left hand—this does not accord with the sequence of the five phases. What is the reason? Qi Bo replied: This is the yin-yang transformation of heaven and earth, and not the sequential movement of the four seasons and five phases. Moreover, the concept of yin and yang has names but no concrete form. Thus, it can be counted up to ten, separated to reach a hundred, dispersed to reach a thousand, and extended to reach ten thousand. This is exactly what is meant.