太冲三焦。内经之论备矣。后世知冲督任分三脉。而不知后曰太冲之义。知中焦起营卫。而不知其为匡济于阳明。
必欲求其为腑之形。以为三焦无状。空有名。是以其说纷纷。皆拘文牵义之徒也。经曰。冲脉者。五脏六腑之海也。五
脏六腑皆禀焉。夫为五脏六腑之海。而脏腑皆禀焉者。岂为一线之冲。而与督脉无关哉。至论三焦。则经曰上焦出于胃
口。并咽之上。贯膈而布胸中。中焦亦并胃中出上焦之后。下焦别回肠注于膀胱。而于阳明胃之经络。则曰循喉咙入缺
盆。下膈属胃。其直者。缺盆下乳内廉。其支者。起胃口下循腹里。下至气街。此与三焦同行在前。故知三焦者。特胃
部上下之匡廓。三焦之地。皆阳明胃之地。三焦之所主。即阳明胃之所施。其气为腐熟水谷之用。与胃居太阴脾之前。
实相火所居所游之地也。故焦者以熟物为义。上焦如雾者。状阳明化物之升气也。中焦如沤者。状化时沃溢之象也。下
焦如渎者。状济泌分别流水之象也。是以名为三焦者。特为两阳合明之胃。与相火之所职言之耳。其为后天谷神。出化
之本。以出营卫。以奉生身。使肾之气上升于肺。下输膀胱。后天之能事毕矣。然人受生以来。其真元一由先天而起。
则少阴为之根柢。厥阴为之冲发。其气皆挟津液以上。历五脏而上之。其气在中后之间。渗灌脊肠。名为太冲。实居阳
明三焦之后。故云后为太冲。太冲之太者。其盛为十二经之海。五脏六腑亦皆禀之。与阳明胃。并是脏腑之根柢也内经
又谓为血海。与少阴之大络。起于肾下。出于气街。又与阳明会于宗筋。于是其后输出大杼。其前会气街。大杼在督。
气街在任。是冲脉之盛。灌三阳。渗三阴。包阳明三焦。凡督任阴阳之会脉。皆冲为之也唯冲为之。故太冲之精气。常
得与三焦营卫之行。合行隧道。而绕周身。充微皮毛。而灌脏腑。人知营卫之出于三焦。而不知先天脉气有与之偕行者。
日夜五六十周。盖先后之天齐至也。人疑卫为水谷之悍气。决出上焦。而经独云卫出下焦。遂疑为误文。不知前言者。
特言饮食之能出卫。而实则卫为真阳。能卫外为固。非可以一时之饮食当之。必先天根柢之盛气。与此为合而当之也。
则卫之出下焦何疑。盖知冲之为义。益知卫之为出矣。
Tai Chong and San Jiao. The discussions in the *Nei Jing* (Inner Canon) are comprehensive. Later generations knew to divide the Chong Mai (Penetrating Vessel), Du Mai (Governing Vessel), and Ren Mai (Conception Vessel) into three meridians, but did not understand the meaning of "the posterior is called Tai Chong." They knew that the Middle Jiao generates Ying Wei (Nutritive and Defensive Qi), but did not know that it assists and supports the Yangming Stomach Meridian.
If one insists on seeking the physical form of the Zang-Fu organs for San Jiao, believing that San Jiao has no shape and only an empty name, then its theories become controversial. These are all scholars who stick rigidly to texts and force interpretations. The Classic states: "The Chong Mai is the sea of the five Zang and six Fu organs; the five Zang and six Fu organs all receive from it." Since it is the sea of the five Zang and six Fu organs, and the organs all rely on it, how could it be merely a thin line of the Chong Mai, unrelated to the Du Mai?
Regarding the discussion of San Jiao, the Classic says: The Upper Jiao originates from the stomach opening, runs along the upper part of the pharynx, penetrates the diaphragm, and spreads in the chest. The Middle Jiao is also within the stomach, emerging after the Upper Jiao. The Lower Jiao separates from the ileum and pours into the bladder. Regarding the meridian pathway of the Yangming Stomach, it states: "It follows the throat, enters the supraclavicular fossa (Quepen), passes through the diaphragm, and belongs to the stomach. The straight branch descends from the supraclavicular fossa along the medial aspect of the breast. The branch originates below the stomach opening, runs along the interior of the abdomen, and descends to the Qich acupoint." These paths run parallel to San Jiao in the front. Therefore, it is known that San Jiao is specifically the framework above and below the stomach region. The area of San Jiao is the area of the Yangming Stomach. What San Jiao governs is what the Yangming Stomach exerts. Its qi functions in the digestion and ripening of food and water. Located anterior to the Taiyin Spleen, it is actually the residence and wandering place of Xiang Huo (Ministerial Fire). Thus, "Jiao" implies cooking or ripening substances. "Upper Jiao like mist" describes the ascending qi of transforming substances by the Yangming Stomach. "Middle Jiao like fermentation vat" describes the imagery of soaking and fermenting during digestion. "Lower Jiao like ditch" describes the imagery of filtering and separating flowing water. Therefore, naming it San Jiao refers specifically to the Yangming Stomach (where two Yangs combine to illuminate) and the duties of Ministerial Fire. It is the root of postnatal grain spirit, the basis of transformation, producing Ying Wei Qi to nourish the body, enabling kidney qi to ascend to the lungs and descend to the bladder, thus completing the functions of the postnatal stage.
However, since human conception, the true Yuan Qi arises entirely from congenital sources. Shaoyin Kidney serves as the foundation, and Jueyin Liver acts as the initiator. This qi carries fluids upward, passing through the five Zang organs. This qi operates between the middle and lower regions, infiltrating the spine and intestines, named Tai Chong. It is actually located posterior to the Yangming San Jiao. Hence, it is said that "the posterior is Tai Chong." The "Tai" in Tai Chong means grand or abundant; it is the sea of the twelve meridians, and the five Zang and six Fu organs all receive from it. Along with the Yangming Stomach, it is the foundation of the Zang-Fu organs. The *Nei Jing* also calls it the Sea of Blood. It connects with the large collateral of Shaoyin, originating below the kidney, emerging at the Qich acupoint, and meeting the Yangming Stomach at the Zongjin (genitals/tendons). Thus, it outputs posteriorly to the Dazhu acupoint and meets anteriorly at the Qich acupoint. Dazhu is on the Du Mai, and Qich is on the Ren Mai. This shows that the abundance of the Chong Mai irrigates the Three Yang meridians and infiltrates the Three Yin meridians, enveloping the Yangming San Jiao. All meridians where Du and Ren, Yin and Yang meet, are governed by the Chong Mai. Only because the Chong Mai does this can the essence and qi of Tai Chong often travel together with the Ying Wei Qi of San Jiao through the tunnels, circling the whole body, filling the skin and hair, and irrigating the Zang-Fu organs. People know that Ying Wei Qi comes from San Jiao, but do not know that congenital meridian qi accompanies it. It circulates fifty to sixty times day and night, indicating that congenital and postnatal natures advance together.
Some suspect that Wei Qi is the fierce qi derived from food and water, exiting from the Upper Jiao, yet the Classic alone states "Wei Qi exits from the Lower Jiao," leading them to doubt it as a textual error. They do not realize that the previous statement specifically refers to diet being able to produce Wei Qi, but in reality, Wei Qi is True Yang Qi, capable of defending the exterior and maintaining solidity. It cannot be substituted merely by temporary dietary intake. It must rely on the abundant qi of the congenital foundation combining with this to fulfill the role. Then, what is there to doubt about Wei Qi exiting from the Lower Jiao? By understanding the meaning of Chong Mai, one further understands the origin of Wei Qi.