卫气并脉循分肉，内伤外感正邪攻，外邪客脉为脉胀，邪留分肉肤胀生。
【注】经曰∶卫气之在身也，常然并脉循分肉行，阴阳相随，何病之有？若其人内伤
七情，外感六气，饮食失节，劳役过度，则邪正相攻，荣卫失和。卫气与风寒之邪客于
脉中，则为脉胀。卫气与风寒之邪留于分肉，则为肤胀也。
脉胀筋起络色变，久成单腹末脱清，肤胀 初不硬，缠绵气鼓胀膨膨。
【注】脉胀之证，腹筋起，络色变，久而
不已，则成单腹胀，四末脱瘦清冷也。肤胀之证， 然初不坚硬，缠绵不愈，则成气
鼓胀满，膨膨急硬也。
外邪干卫客肠外，肠覃月事以时行，外邪干营客胞内，石瘕经闭状妊盈。
【注】风寒之邪，不客于脉中分肉，而干卫气、深入客于肠外，僻而内着，日以益大，
状如怀子，月事仍以时行，名曰肠覃。或干营气，深入客于胞中，恶血留止，日以益大，
状如怀子，月事不以时下，名曰石瘕。此皆生于女子，在男子则为疝病也。
皮浓色苍多是气，皮薄色泽水湿成，气速安卧从上下，水渐难眠咳喘征，石水少腹
肿不喘，风水面肿胫足同，石水阴邪寒水结，风水阳邪热湿凝。
【注】凡肿胀之病，皮浓色苍者，皆属气也。皮薄色泽者，皆属水也，气，阳也，阳
性急，故为胀速，每从上肿而渐下，得以安卧，邪在外也。水，阴也，阴性迟，故为胀
渐，每从下肿而渐上，更有咳喘不得卧之征也。石水之证，少腹肿满，水在下，故不喘
也。上肿曰风，下肿曰水。故风水之证，面与胫足同肿也。然石水属阴邪，故曰寒结也。
风水属阳邪，故曰热湿凝也。
Wei Qi (Defensive Qi) circulates along the vessels within the muscle spaces. Internal injury and external pathogenic invasion cause a conflict between righteous Qi (Zheng Qi, healthy energy) and pathogenic factors. When external pathogens lodge in the vessels, it results in Mai Zhang (Vessel Distension); when pathogens remain in the muscle spaces, Fu Zhang (Skin Distension) arises.
[Note] The Classic states: Wei Qi (Defensive Qi) in the body constantly follows the vessels and circulates within the muscle spaces, with Yin and Yang following each other; how could disease occur? If a person suffers internal injury from the Seven Emotions (Joy, Anger, Worry, Pensiveness, Sorrow, Fear, Fright), or external contraction of the Six Climates (Wind, Cold, Summer-heat, Dampness, Dryness, Fire), irregular diet, or excessive labor, then pathogens and righteous Qi attack each other, causing Ying Qi (Nutritive Qi) and Wei Qi (Defensive Qi) to lose harmony. When Wei Qi (Defensive Qi) and Wind-Cold pathogens lodge in the vessels, it forms Mai Zhang (Vessel Distension). When Wei Qi (Defensive Qi) and Wind-Cold pathogens remain in the muscle spaces, it forms Fu Zhang (Skin Distension).
Mai Zhang (Vessel Distension) presents with raised abdominal veins and altered collateral colors. If prolonged without resolution, it develops into Dan Fu Zhang (Single Abdominal Distension), characterized by emaciation and coldness of the four extremities. Fu Zhang (Skin Distension) is initially soft, but if lingering and unresolved, it evolves into Qi Gu (Qi Drumming), presenting as a distended and swollen abdomen.
[Note] In the syndrome of Mai Zhang (Vessel Distension), abdominal veins are prominent, and collateral colors change. If left untreated for a long time, it becomes Dan Fu Zhang (Single Abdominal Distension), with the four extremities becoming emaciated and cold. In the syndrome of Fu Zhang (Skin Distension), the abdomen is not hard initially. If lingering and unresolved, it becomes Qi Gu (Qi Drumming), with abdominal fullness, distension, and tight hardness.
External pathogens interfere with Wei Qi (Defensive Qi) and lodge outside the intestines, resulting in Chang Tan (Intestinal Polyp/Tumor) where menstruation occurs on time. External pathogens interfere with Ying Qi (Nutritive Qi) and lodge inside the uterus, resulting in Shi Xia (Stone Fibroid) causing amenorrhea, with the abdomen enlarging as if pregnant.
[Note] Wind-Cold pathogens do not lodge in the vessels or muscle spaces, but instead interfere with Wei Qi (Defensive Qi) and deeply lodge outside the intestines. They attach obliquely internally, growing larger day by day, resembling pregnancy, yet menstruation continues regularly; this is named Chang Tan (Intestinal Polyp/Tumor). Or, they interfere with Ying Qi (Nutritive Qi) and deeply lodge in the uterus, where evil blood stagnates and grows larger day by day, resembling pregnancy, yet menstruation is delayed; this is named Shi Xia (Stone Fibroid). These conditions occur in women; in men, they manifest as Hernia diseases (Shan Bing).
Thick skin and dark complexion usually indicate Qi stagnation; thin skin and bright luster indicate Water-Dampness accumulation. Qi distension develops rapidly, allows for comfortable lying down, and typically spreads from top to bottom. Water distension develops gradually, causes difficulty sleeping, and manifests with coughing and wheezing. Shi Shui (Stone Water) presents with lower abdominal swelling without wheezing. Feng Shui (Wind Water) presents with simultaneous swelling of the face and lower legs/feet. Shi Shui (Stone Water) is a Yin pathogen formed by the congealing of cold water. Feng Shui (Wind Water) is a Yang pathogen formed by the coagulation of heat and dampness.
[Note] In all swelling diseases, thick skin and dark complexion belong to Qi disorders. Thin skin and bright luster belong to Water disorders. Qi belongs to Yang; Yang nature is urgent, so Qi distension occurs quickly, usually starting from the upper body and spreading downward, allowing the patient to lie comfortably, as the pathogen is exterior. Water belongs to Yin; Yin nature is slow, so Water distension occurs gradually, usually starting from the lower body and spreading upward, accompanied by signs such as coughing, wheezing, and inability to lie flat. In Shi Shui (Stone Water), there is lower abdominal swelling and fullness; because the water is located below, there is no wheezing. Swelling above is called Wind; swelling below is called Water. Therefore, in Feng Shui (Wind Water), both the face and the shins/feet swell simultaneously. However, Shi Shui (Stone Water) belongs to Yin pathogens, hence it is described as Cold Congealment. Feng Shui (Wind Water) belongs to Yang pathogens, hence it is described as Heat-Dampness Coagulation.