However, due to historical reasons, Chinese medicine gradually lost the complete explanation of the essence of meridians in Huangdi Neijing before the Song Dynasty. For example, from the Han Dynasty to the Song Dynasty, the nine volumes of Lingshu, which specifically discussed the laws of qi and blood movement in human meridians and the principles of acupuncture, have been handed down only as remnants. By the end of the Northern Song Dynasty in 7950, North Korea presented the Yellow Emperor's Needle Sutra, and the lost part of the spiritual pivot was recovered. However, due to the change of context and grammar, the later generations can't fully understand the explanation of meridians in Huangdi Neijing Lingshu. Therefore, the explanation of the essence of meridians is still buried.
Li Shizhen, a famous doctor in Ming Dynasty, pointed out in Eight Veins of Strange Classics that Yin Meridian and Yang Meridian are interlinked, like a circle, with no beginning and no end. Its overflowing qi enters the strange meridians, irrigates each other, warms the internal organs and moistens the external acupoints. Strange classics unify the eight classics and are not limited to the twelve classics, so they are called strange classics.
Mr. Li Shizhen answered what is "the eight strange meridians", and also answered "the insider sees clearly". But it doesn't tell us the meridians.
The origin of meridians does not tell us what the essence of meridians is.
Influenced by scattered anecdotes and lost classics of traditional Chinese medicine, the meridian theory is gradually mixed with some misinterpretations and misunderstandings. In order to clarify these misunderstandings and interpret the essence of meridians, it is necessary to make a careful analysis of the classics in combination with the knowledge of ancient astronomy and meteorology in China related to meridians.