Taiyang Disease
Taiyang (Greater Yang) and Shaoyin (Lesser Yin) represent the exterior and interior, respectively, and are differentiated by Yin and Yang. If the pulse is floating, with fever and aversion to cold, it indicates a disease occurring in Taiyang, known as Yang syndrome. Conversely, if the pulse is deep, without fever but with aversion to cold, it indicates a disease occurring in Shaoyin, known as Yin syndrome.
1. Taiyang Disease: Exterior and Interior Syndromes
(1) Taiyang Disease Exterior Syndrome: Among the six meridians, only Taiyang disease can represent the exterior syndrome, which is closely related to the physiological characteristics of Taiyang. The Taiyang meridian connects to the Fengfu (Wind Mansion) and governs all Yang Qi, thus it oversees the six meridians and regulates the Ying and Wei (Nutrient and Defensive Qi), serving as the body’s external barrier. Therefore, Taiyang governs the exterior. Additionally, each of the six meridians has its own organ and bowel distinctions; when a meridian is affected by pathogenic factors, it can manifest as an exterior syndrome due to its external location.
The “Shang Han Lun” states: “If both the cun and guan pulses are floating, it indicates a disease in Taiyang, which should manifest within one or two days. This is because the pulse connects to the Fengfu, leading to headache and stiffness in the lumbar spine.” The symptoms described in the first section of the “Shang Han Lun”—floating pulse, headache, stiffness in the neck, and aversion to cold—illustrate the characteristics of pathogenic factors harming the Taiyang meridian and the resulting disease.
(2) Taiyang Disease Interior Syndrome: The organ associated with Taiyang is the Bladder, located in the lower jiao (lower abdomen). If the pathogenic factor in the Taiyang meridian does not resolve, it can enter the organ, leading to conditions such as water retention and blood stasis. This is referred to as the interior (organ) syndrome of Taiyang disease.
Taiyang Water Retention Syndrome: Characterized by a floating pulse, slight fever, thirst with a desire to drink, and difficulty urinating, it may even lead to vomiting after drinking, known as “water reversal.”
Taiyang Blood Stasis Syndrome: In Taiyang disease, a weak and deep pulse reflects the invasion of exterior pathogenic factors into the interior. Symptoms may include hardness and fullness in the lower abdomen, mental agitation; or urgent abdominal distension with a frenzied state, yet urination remains normal, indicating heat and blood stasis, unrelated to water.
2. Taiyang Disease: Cold and Heat Syndromes
(1) Taiyang Disease Cold Syndrome: Taiyang governs the exterior, yet there is a distinction between cold and heat in exterior diseases that must be noted. For instance, the third section of the “Shang Han Lun” states: “In Taiyang disease, whether there is fever or not, there must be aversion to cold, body aches, vomiting, and a tight pulse, which is termed as Shang Han (Cold Damage).” This reflects the characteristics of exterior cold as a disease, thus it can be termed as Taiyang Disease Exterior Cold Syndrome.
(2) Taiyang Disease Heat Syndrome: Where there is cold, there must be heat; this is a relative phenomenon. The exterior heat syndrome of Taiyang disease manifests in two forms: one is the invasion of warm pathogenic factors, as described in the sixth section of the “Shang Han Lun”: “In Taiyang disease, if there is fever and thirst, without aversion to cold, it is termed as a warm disease.” Since the warm pathogenic factor remains in Taiyang and has not fully entered the interior, it is called Taiyang Disease Exterior Heat Syndrome. The other form occurs when wind-cold constrains the exterior for an extended period, leading to cold stagnation transforming into heat, where the pulse changes from tight to relaxed, body pain shifts to heaviness, and there is no sweating with mental agitation, which can also be termed as Taiyang Disease Exterior Heat Syndrome. Additionally, the 27th section states: “In Taiyang disease, if there is fever with aversion to cold, more heat than cold… it is appropriate to use Gui Zhi (Cinnamon Twig) Decoction with Er Chen Tang (Two Aged Decoction),” which also belongs to the category of Taiyang Disease Exterior Heat Syndrome.
3. Taiyang Disease: Deficiency and Excess
(1) Taiyang Disease Exterior Deficiency Syndrome: In Taiyang disease, if there is sweating from the exterior syndrome, it is termed as exterior deficiency syndrome. For example, the twelfth section of the “Shang Han Lun” states: “In Taiyang wind, if Yang is floating and Yin is weak, Yang floating indicates heat is self-generated; Yin weakness indicates sweating occurs. If there is aversion to cold, aversion to wind, fever, nasal congestion, and dry vomiting, Gui Zhi Decoction is the main treatment.” This describes the deficiency syndrome of the exterior pathogenic factor in Taiyang disease.
(2) Taiyang Disease Exterior Excess Syndrome: In Taiyang disease, if there is no sweating but wheezing, it is termed as exterior excess syndrome. For instance, the thirty-fifth section of the “Shang Han Lun” states: “In Taiyang disease, if there is headache, fever, body aches, lumbar pain, joint pain, aversion to wind, and no sweating but wheezing, Ma Huang Decoction is the main treatment.” This describes the excess syndrome of the exterior pathogenic factor in Taiyang.
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Hu Xishu: The Exterior, Interior, and Half-Exterior Half-Interior in the “Shang Han Lun”