Among the things I find fascinating about Chinese medicine are 1) the sheer vastness of it, and 2) the degree to which a passing mention of something in the canon can be a springboard into a whole area of theoretical and clinical development. Perhaps the most celebrated example of thing 2 is the Shānghán Lùn, which is based off a brief passage in Huángdì Nèijīng Sùwèn but was expanded upon to become an entire school of practice which thrives even today. I recently happened upon another example of this type of historical development which had escaped my attention for thirty-odd years.
I was researching wind medicinals [fēngyào 風藥] for the treatment of pain. Wind medicinals in this case means warm acrid exterior-resolving, a.k.a wind-cold and wind-damp herbs. In mining the Chinese literature for the topic, I came across several references to xuánfǔ theory [玄府理論 xuánfǔ lǐlùn]. As I was unfamiliar with this topic, I delved deeper… and deeper…
The Mysterious House
The Practical Dictionary of Chinese Medicine (Wiseman & Feng, 1998) defines the term this way:
玄府 xuánfǔ
Mysterious house. Also [translated] original mansion. A sweat pore; so called because it is not visible to [the] naked eye. Plain Questions (素问su4 wen4, jing1 lun4), first part of huang2 di4 nei4 jing1黄帝内经 states, “When the upper burner is inhibited, then the skin becomes tight, the interstices close, the mysterious houses become blocked, and defense qi4 fails to be discharged; hence there is external heat.'' [上焦不通利，則皮膚緻密，腠理閉塞，玄府不通，衛氣不得泄越，故外熱。]
The other reference from Sùwèn that gets cited often in the literature is from Discussion of points for water and heat [Shuǐ rè xué lùn, 水熱穴論]:
勇而勞甚則腎汗出，腎汗出逢於風，內不得入於臟腑，外不得越於皮膚，客於玄府，行於皮里，傳為胕腫，本之於腎，名曰風水。所謂玄府者，汗空也。
“If one is valiant and labors to extremes, the kidney sweat will come out, when the kidney sweat comes out it meets the wind, but it will not reach the viscera and bowels inside, and will not pass through the skin outside, instead it lodges at the xuánfǔ , moving within the skin and spreading to cause swelling, its root is in the kidney, it is named wind water. What is called xuánfǔ is the sweat orifices.” [Mulch translation]
Seems pretty straightforward. But, as it turns out, xuánfǔ took on an extended meaning in the writings of Líu Wánsù [劉完素], and through that developed later into a theoretical school. Interestingly, Líu’s most notable mention of xuánfǔ came in a discussion of ophthalmology. The passage comes from Etiology Based on Plain Questions [素問玄機原病式 Sùwèn xuánjī yuán bìng shì], in the chapter concerning dim and blurry vision [目眜不明]. Here is the mulch version:
然皮膚之汗孔者，謂泄氣液之孔竅也，一名氣門，謂泄氣之門也。一名腠理者，謂氣液出行之腠道紋理也；一名鬼神門者，謂幽冥之門也；一名玄府者，謂玄微府也。
The sweat pores of the skin refer to the empty orifices of qì and fluid discharge, also called qìmén, which means the gate of qì discharge. Another name is còulǐ [striations], meaning the lines, pathways and veins where the qì and fluid exit; they are also called guǐshén mén [ghost spirit gate], meaning the gate of the nether world; they are also called xuánfǔ [mysterious house], also known as xuánwēifǔ [mysterious tiny houses, or dark micro-palaces].
然玄府者，無物不有，人之臟腑、皮毛、肌肉、筋膜、骨髓、爪牙，至於世之萬物，盡皆有之，乃氣出入升降之道路門戶也。夫氣者，形之主，神之母，三才之本，萬物之元，道之變也。
As for xuánfǔ, there is nothing that does not have them: the humans’ zàngfǔ, skin and hair, muscles and flesh, sinews and membranes, bones and marrow, nails and teeth, extending to everything in creation without exception, they are the pathways and gateways where the qì exits and enters, ascends and descends. This qì is the master of form, the mother of spirit, the root of the three talents [i.e. heaven, humans and earth], the source of all things, and the way [dào] of transformation.
故元陽子解《清靜經》曰：大道無形，非氣不足以長養萬物，由是氣化則物生，氣變則物易，氣甚即物壯，氣弱即物衰，氣正即物和，氣亂即物病，氣絕即物死。《經》曰：「出入廢，則神機化滅。升降息，則氣立孤危。故非出入則無以生、長、化、收、藏。是以升降出入，無器不有。」
Hence Yuán Yángzǐ explained in Qīngjìng Jīng [Classic of Pure Equanimity]: The great way is without form, this does not mean the qì is insufficient to grow and nourish all things, because the transformation of qì causes the the engenderment of things, qì transformation is how things change; if qì is strong then things will strengthen, if qì is feeble then things will decline, if qì is upright then things are harmonious, if qì is in disorder then things fall ill, if qì is cut off then things die. The classic says: “If the exit and entry are abolished, then the spirit mechanism’s transformation will perish. If the ascending and descending cease, then the qì stands alone in peril. Thus if there is no exit and entry there will be no engenderment, growth, transformation, gathering and storing. So through ascending and descending, exit and entry, there is no lack of capacity [i.e. there is nothing it cannot do].”
人之眼、耳、鼻、舌、身、意、神識，能為用者，皆由升降出入之通利也，有所閉塞者，不能為用也。若目無所見，耳無所聞，鼻不聞臭，舌不知味，筋痿骨痹，齒腐，毛髮墮落，皮膚不仁，腸不能滲泄者，悉由熱氣怫鬱，玄府閉密而致，氣液、血脈、榮衛、精神。不能升降出入故也。各隨鬱結微甚，而察病之輕重也。
The human’s eyes, ears, nose, tongue, body, thought, and consciousness, and the use of one’s skill is all due to freeing and facilitating the ascending and descending, exit and entry; if there is blockage these things cannot be used. If the eyes cannot see, ears cannot hear, nose cannot smell, tongue cannot recognize tastes, sinew wilts and bone obstructs, teeth rot, hair withers and falls, skin grows numb, the intestines cannot percolate and drain, it is entirely due to heat from qì depression, which causes the xuánfǔ to become closed tightly; this then extends to the qì and fluids, blood vessels, provisioning and defensive [qi], and essence spirit. The reason for this is [the qi] cannot ascend and descend, exit or enter. One can observe the lightness or heaviness of the disease as it varies with the severity of the depressive knotting of the tiny [xuánfǔ].
故知熱鬱於目，無所見也。故目微昏者，至近則轉難辨物，由目之玄府閉小也，隔縑視物之象也。或視如蠅翼者，玄府有所閉合者也。
Thus we know that when there is depressive heat in the eyes, one cannot see. So if the eyesight is slightly dim, it will progress so that it is difficult to distinguish things, because the xuánfǔ of the eyes closes small, such that it appears as if one is looking at things through a silk partition. Or if it looks like fly’s wings, this is from the xuánfǔ closed shut.
So, far from being limited to the sweat pores, xuánfǔ according to Líu are all-pervading microstructures which form the routes through which the qì and fluids move up and down, in and out, and with them move all other things, including the spirit.
Later Developments
Xuánfǔ theory gets taken up again in the 20th century by the ophthalmologist Chén Dáfū [陈达夫] from Sìchuān, who combined six-channel theory with xuánfǔ theory (Yè, 2024). His disciple, Wáng Míngjié [王明杰], continued this research and has written extensively about xuánfǔ theory. They postulate that xuánfǔ are everywhere in the human body, microscopic edifices whose nature is to remain open and unblocked. When the xuánfǔ are blocked, then disease results, and the available research shows that the diseases with which this pathomechanism is associated go far beyond ophthalmology: some of the papers I have read focus on hypertension, menopausal symptoms, migraines, facial paralysis, kidney diseases, and so forth.
Relationship with Network Vessels
This sounds similar to developments in network vessel theory; and indeed some of the papers do combine the two, citing “xuánfǔ-luòmài lǐlùn” [玄府－络脉理论] (Liú & Wáng, 2024). The difference as I understand it is that the network vessels are structurally part of the system of channels and vessels where the xuánfǔ are found in all tissues, from the surface to the bones. Liú & Wáng (2024) do cite some authors who relate the xuánfǔ to the sūnluò [孫絡] or grandchild networks, and say that the two form a sort of complex super-network in which the xuánfǔ are a gateway to the network vessel system. Another characteristic of the xuánfǔ is that they are portals, as distinct from the conduit structure of the network vessels, and thus they open and close. And, as we will see, the treatments for each of these structures differ.
Relationship with Organs
One of the developments that has occurred over time is the idea that each of the organs has its own xuánfǔ. In their paper on using xuánfǔ theory to treat hypertension, Huáng & Huáng (2024) list the functions of the xuánfǔ of five organs, which are summarized here.
Liver xuánfǔ: The liver’s xuánfǔ is the route for the freecoursing of qì . If the liver is harmonious, the freecoursing of qì will be constant, easy and unimpeded, and the liver's xuánfǔ will open and close accordingly. Lín Pèiqín (Lín, 1839) says "The liver and gallbladder are innately the viscera of wind and wood, and the fire phase resides within them [良由肝膽乃風木之臟，相火內寄]," so when the coursing and discharging of the wood phase is depressed, the fire within will become hyperactive and, as Líu Wánsù said, cause the xuánfǔ to close tightly. Opening the liver's xuánfǔ, then, is seen as a crucial part of relieving depressed wood and clearing depressed fire.
Heart xuánfǔ: The heart's xuánfǔ is the route for the circulation of blood. As mentioned earlier, the network vessels and xuánfǔ are linked, and if the heart's xuánfǔ are blocked, it will result in blockage of the network vessels and vice versa.
Spleen xuánfǔ: The spleen's xuánfǔ is the route for the distribution of the essences of food and fluids. Upon separating the clear essences of food and drink, the spleen distributes them to the four limbs through its xuánfǔ. If the spleen is unable to properly transform, turbidity builds up and obstructs the spleen's xuánfǔ, making it impossible to distribute the clear essence or to raise it to the upper burner, resulting in systemic damp turbidity and phlegm.
Lung xuánfǔ: The lung's xuánfǔ is the route for the entry and exit of the provisioning [yíng] and defensive [wèi] qì . If the lung xuánfǔ does not properly open and close, the circulation of defensive qì will be impaired and the body will be beset with exterior evils. The original sense of the xuánfǔ as described above is the sweat orifices, and the function of sweating is closely related to the lung's xuánfǔ. If the lung's diffusing function is impeded by a blockage of the xuánfǔ, the downbearing function will be disrupted as well, affecting its functions of governing qì and maintaining regular flow through the waterways.
Brain xuánfǔ: The brain's xuánfǔ is the route for the activities of the spirit mechanism. The spirit mechanism regulates spirit, emotion, consciousness, and cognition. Long term blockage of the brain's xuánfǔ restricts blood circulation to the brain, and thus the spirit will lose its abode. Cognitive, sensory, and behavioral deficits may result.
This is but a brief overview of what I have learned of xuánfǔ theory. The next question is: how does one go about treating this pathomechanism? In the next couple of posts I will write about some of the ways to treat xuánfǔ with herbal medicine and acupuncture. Thanks for reading.
Note: this publication is for information purposes only and is not intended as medical advice. Please seek the opinion of a health care professional for any specific medical issues you may have.'
References
Huáng, Y., & Huáng, F. (2024). The application of flower medicine in treating hypertension based on the xuanfu theory. Clinical Journal of Chinese Medicine, 16(29), 105-109. doi:10.3969/j.issn.1674-7860.2024.29.020
Huángdì Nèijīng Sùwèn. (n.d.). Retrieved March 12, 2024, from https://jicheng.tw/tcm/book/%E9%BB%83%E5%B8%9D%E5%85%A7%E7%B6%93%E7%B4%A0%E5%95%8F/index.html
Lìn, P. (1839). Lèi zhèng zhì cái. Retrieved January 14, 2024, from https://jicheng.tw/tcm/book/%E9%A1%9E%E8%AD%89%E6%B2%BB%E8%A3%81/index.html.
Liú, J. , & Wáng, B. (2024). Study on differentiation and treatment of hypertension based on the "sweat pore-collateral vessel" theory. Henan Traditional Chinese Medicine, 44(12), 1841-1844. DOI:10.16367/j.issn.1003－5028.2024.12.0332
Líu, W. (1188). Sù wèn xuánjī yuánbìng shì. Retrieved January 2, 2025, from https://jicheng.tw/tcm/book/%E7%B4%A0%E5%95%8F%E7%8E%84%E6%A9%9F%E5%8E%9F%E7%97%85%E5%BC%8F/index.html
Wiseman, N., & Feng, Y. (1998). A practical dictionary of Chinese medicine. Paradigm Publications.
Yè, Q. (2024). Research on xuánfǔ theory. Journal of Chengdu University of Traditional Chinese Medicine, 47(6), 1-3.