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A collection of notes on the topics of classical Chinese, medicine, and traditional culture.

Random Thoughts on "Water is Yīn, Fire is Yáng"


Water is yīn; fire is yáng. Yáng is qì; yīn is flavor. 

A commentary on this quote from Sù Wèn 5 from the Lèi Jīng:

“Thus in Heaven, the sun and moon are water and fire; in the Yì Jīng, [the trigrams] kǎn and lí are water and fire; in medicine, the heart and the kidney are water and fire; and in alchemy, essence and qì are water and fire. Now the kidney is water, and the generation of qì inside water is precisely true fire; the heart is fire, and the generation of fluids inside fire is precisely true water. The mutual storage of water and fire within each other, this is where the utmost Dào is located, and this is what any physician should first examine attentively.”

The commentary on this line from Zhāng Jièbīn’s Lèi Jīng, which was published in 1624, is interesting to me for a number of reasons. Of course we should never consider an interpretation that is more than a thousand years removed from the original compilation of the Nèi Jīng as authoritative or the only possible reading. Nevertheless, we can learn a lot about historical Chinese medicine from these sorts of comments, especially if we contextualize them with similar literature from the same time period.

First, what this passage shows us is not unfortunately how the original authors, compilers, and readers of the Nèi Jīng understood this seemingly simple line, and read the entire Nèi Jīng as a whole. Nevertheless, we can get a glimpse of how physicians and medical authors in the late Míng period approached and contemplated such seemingly simple passages as “Water is yīn; fire is yáng.” As such, fire and water (and thus by implication yáng and yīn) are here read in the following contexts: in astronomy as sun and moon; in cosmology, couched in the language of the Yì Jīng 易經, as the two basic trigrams kǎn and lí (water as a solid yáng line enclosed by two broken yīn lines, and fire as a broken yīn line enclosed by two solid yáng lines); in medicine as the two zàng organs heart and kidney; and in alchemy as the precious substances qì and jīng essence, respectively.

The art of the physician, like the arts of the philosopher, cosmologist, astronomer, diviner, and alchemist, can thus be said to be encapsulated in this ability to transcend realms, or microcosmic perspectives, and to grasp the multiple dimensions of any situation, to thereby plumb its meaning more fully and ultimately from a macrocosmic perspective. Sages or “seers” are able to access the associations and experiences they might have in any one of these contexts and relate them to all the other contexts. Thereby they can shed light for themselves and others on this interaction of the two most basic forces of life, yīn and yáng, water and fire, and then apply this insight to any context and microcosm, from politics to agriculture to medicine and to internal and external alchemy. Understanding the life-giving dance between these two foundational elements in the cosmos is the cornerstone of the sage’s ability to decipher the sky and make calendric predictions in astronomy, to assess a given situation by means of the 64 hexagrams of the Yì Jīng and predict future potentials and risks in divination, to diagnose and treat illness in medicine, and to cultivate oneself and ultimately achieve transcendence of the restraints of the human body, or in other words immortality, in alchemy.


Ultimately, what all these skills have in common is the ability to understand the direction of change from that which has already manifested to that which has not manifested yet. Seeing the seed of invisible future developments by accurately assessing the visible present in light of the direction and dynamic of past changes allows the sage to position him- or herself in alignment with the Dào, to act in a manner that is shùn (following along with the currents) instead of (going against the current). Two modern equivalents of this skill may be to ride the waves of change like a skilled surfer or to plant in harmony with short- and long-term celestial cycles as an experienced biodynamic farmer.

As a physician, an expression of this skill might be in the choice of therapeutic interventions with which to support a woman trying to conceive at any given moment, from fine-tuning her menstrual cycle to possibly providing acupuncture during an IVF procedure, but also taking her age, past reproductive experiences, work environment, personal and social life, family history, astrological chart, diet and lifestyle, signs of momentary alignment or misalignment with her external environment, and other factors into consideration. In a case like this, how can the simple statement “water is yīn; fire is yáng” enrich a physician’s understanding of the interaction of the heart and kidney in the innermost wheel of physiology that makes human life possible? And how might it increase the physician’s understanding in a clinical encounter to meditate on the trigrams kǎn and lí , whose inherent stability comes perhaps from the fact that they both contain their opposite in the yīn-yáng complementarity of their lines. As the commentary points out, “Now the kidney is water, and the generation of qì inside water is precisely true fire; the heart is fire, and the generation of fluids inside fire is precisely true water.” Similarly, the Sù Wèn then goes on to discuss flavor and qì in medicinal substances as yīn and yáng respectively, but then emphasizes the need to differentiate further between yīn and yáng aspects of each of them. Thus we have a yīn aspect of yáng, and a yáng aspect of yīn, or in other words water within fire and fire within water. What might an understanding of solar and lunar cycles, and the effect of these cycles on life on earth, contribute to the way in which we look at physiological functions and pathological actions of the heart and kidney?

On the surface, the significance of the interaction between essence and qì in alchemical practices on the physician’s understanding of the heart-kidney axis might be more obvious to the contemporary practitioner of Chinese medicine. Nevertheless, in an agricultural society without modern refrigeration and transportation, the effects of the moon and sun on crops and livestock through the circulation of fluids and effect of heat on the natural environment were just as helpful for grasping the polysemic significance of yīn and yáng. The frequent references in Sù Wèn 5 to climate, natural processes, and agricultural knowledge are a dimension of this text, and thus a source of insight, that we modern humans may not be able to fully grasp given how far our technology-dependent lifestyle has removed us from a life embedded in nature.

One last aspect of the above quote from the Lèi Jīng is worth pointing out: In contrast to a current trend in Chinese medicine of integrating theories and practices from traditional Chinese alchemy, or religion, into medicine, Zhāng Jièbīn differentiates clearly between the world of dān , in the narrowest sense meaning “cinnabar” but by extension also “elixir” and hence here “alchemy” or the practitioner thereof, and (medicine). It might surprise modern readers that the pair jīng and is thus specifically positioned outside the purview of medicine. But the Lèi Jīng is not the only text to separate alchemical and medical knowledge in this way while at the same time emphasizing the need for specialists in both fields to know the territory of the other. To cite just one prominent example, Chip Chace and Miki Shima have shown that Lǐ Shízhēn 李時珍, the late sixteenth century author of the Běncǎo Gāng Mù 本草綱目, also differentiated carefully between these two spheres in his Qí Jīng Bā Mài Kǎo 奇經八脈考 (“Investigation of the Eight Extraordinary Channels”). Thus he explicitly states the significance of the extraordinary vessels not only for the physician but also for what Shima and Chace call the “Daoist adept.” For example, Lǐ emphasizes the need for both sides to be well-informed of the other's perspective in his preface: “If physicians are not aware [of such theories of the extraordinary channels], they will remain in the dark as to the cause of disease. If [aspiring] transcendents are not aware [of the more comprehensive theories of the extraordinary channels], it will be difficult for them to tame the furnace and the cauldron (Charles Chace and Miki Shima, An Exposition on the Eight Extraordinary Vessels, p. 96). It may behoove us as modern readers to learn something from this attitude of open-minded interest paired with mutual respect for and recognition of the technical expertise and long arduous training necessary to become proficient at one or the other of these two specialties, instead of picking and choosing random aspects from one field to incorporate into one’s practice of the other. Just some thoughts on a rainy afternoon...    


Sabine WilmsComment