Founder’s Note : This is the second of a series of articles we’ll be releasing here about the theory and herbs of the Tang ye jing. The enthusiasm and scholarly integrity of the author – regular contributor Joshua Park, DSOM, LAc – will make this a thought provoking and engaging read that we hope you’ll share with friends and colleagues. Joshua is eager to hear your feedback, either here on the site or on our Facebook page.
Let’s proceed beyond the introduction by jumping into an exploration of the 25 herbs referenced in the Tang Ye Jing (TYJ).
Because we conceived of this series in the late autumn, we decided to start with the metal class herbs. The text tells us…
All sour belongs to metal, for it is governed by Wuweizi, and Zhishi is wood, Chi is fire, Shaoyao is earth, and Shuyu [better known to modern practitioners as Shanyao] is water.
Let’s start with the wood herb, since that’s the phase of initiation. Zhishi is the unripe fruit of the bitter orange (Fructus aurantii immaturus). It’s placement here as the Wood of Metal might seem a bit puzzling at first. After all, being that it’s bitter orange, it’s most well known for its bitter flavor. This probably leads you to wonder why a a bitter herb classified as belonging to the Metal Phase, when the TYJ has just told us that sour belongs to Metal.
Sometimes classical herbalists see a Chinese herb differently from more modern practitioners.
And this is especially important to keep in mind when studying Zhang Zhongjing’s formulas. In this case however, the ancient sources tend to agree in emphasizing Zhishi’s bitter properties. Consider its entry in the Shen Nong Ben Cao Jing (神農本草經):
Zhishi: Its flavor is bitter and cold. It governs treating great wind within the skin causing severe itching as if caused by hemp seeds, removes cold and heat hot knotting and stops diarrhea. It promotes growth of flesh and muscle, benefits the five zang, increases qi and lightens the body. It grows in rivers and marshes.
If Zhishi is bitter, why is it classed as a Sour herb in the TYJ?
Contemplating this question will help us better understand the clinical uses of Zhishi, as well how the TYJ classifies herbs.
Let’s consider the action of bitter: we know from the first entry in this series that according to the Neijing, bitter hardens or consolidates (堅). But bitter also drains downward. This downward movement also belongs to Metal, which descends as well as gathers. One of the main functions of the Lung, as the Metal zang, is the descent of qi and fluids. The descending action of Lung qi is also responsible for pushing out waste through its paired fu organ, the Large Intestine. In terms of the activity of the Six Conformations, Dry Metal belongs to Yangming, whose activity of closing (合) can also be understood as a kind of descent, and this conforms with the physiological function and direction of the “Stomach Family” (胃家) in taking in food and pushing it through the body via peristalsis.
From this perspective, Zhishi belongs to Metal because it descends.
What does it mean to say that it belongs also to Wood, that it is the “Wood of Metal”? One way of understanding this is that it mediates the relationship of Metal to Wood. In terms of the Five Phases, the Lung’s descent balances the ascent of the Wood zang, the Liver, which is in charge of ascending qi. We know that Metal Controls Wood via the Controlling Cycle. When Wood is excessive, it is checked by the descending mandate of Metal. Through its activity of descending, Zhishi can check the excessively upbearing activity of Wood by promoting the activity of Metal. When the Shen Nong Ben Cao Jing says that it treats knotting (結), we can understand this to be referring to the knotting of qi that occurs from constraint when Liver Wood is in excess.
Zhishi can cut through this by descending, in effect we might say this is helping Metal to control Wood.
If this seems abstract, let’s consider some famous formulas that employ Zhishi. Commonly, Zhishi is employed in formulas when there is considerable qi stagnation in the chest and abdomen, and more specifically, within those cavities of the chest and abdomen that belong to Yangming, and thus to Metal.
We can see this when it is paired with Baishao (the Earth of Metal) to form Zhishi Shaoyao San (枳實芍藥散). In the Jin Gui Yao Lue, this two herb formula was indicated for abdominal fullness and vexing pain in postpartum women (產後腹痛煩滿) and it is often used as a relatively gentle way to treat to constipation. Zhishi breaks through abdominal knotting and promotes the descending of the Yangming, promoting bowel movements, while Baishao soothes, softens and moistens.
From a Five Phase perspective, we can understand this as involving a disharmony between Wood and Metal, which is in turn affecting the Earth Phase.
In addition to Zhishi and Bai Shao, Si Ni San contains Zhi Gan Cao (thereby incorporating Shao Yao Gan Cao Tang, a formula we will explore when we look at Bai Shao Yao) as well as Chai Hu. Zhishi performs the same functions of descending through the Yangming spaces to move through stagnation, while Bai Shao soothes and nourishes Jueyin Wood, but Zhishi’s activity also synergizes with Chai Hu as well as Bai Shao. Chai Hu has an overall lifting action, which balances Zhishi’s descending action.
If we wanted to consider this in terms of the zang fu, we can understand Chai Hu as acting more on the Liver, while Zhishi acts on the Gallbladder.
Chaihu promotes the upbearing activity of the Liver, while Zhishi promotes the downbearing activity of the Gallbladder. Balancing the upbearing and downbearing activity of the Wood zang and fu in turn helps to balance the upbearing and downbearing of the central pivot of the Spleen and Stomach. Regulating ascending and descending in this fashion is one characteristic of the harmonizing method (和法) in Chinese herbalism.
Other formulas that demonstrate the descending activity of Zhishi are the Cheng Qi Tang (承氣湯) family of formulas, which emphasize Zhishi’s action on the Yangming organs well as Wen Dan Tang (溫膽湯), which emphasizes its ability to descend the Gallbladder.
Hopefully by now it’s clear why Zhishi is grouped with Metal, and also what it means to say that it is the Wood of Metal.
This analysis should hopefully also emphasize something about the classical perspective: there’s a kind of fluidity to certain categories. Things like the flavor of an herb, or even what organs that herb effects, are not entirely fixed or consistent. This can seem quite maddening if you are used to the more rigid categorizations of TCM, or if you’re just a Metal individual that likes things to be orderly and tidy. What’s important to pay attention to, however, is the qi dynamic. Zhishi belongs to Metal because it descends, and therefore, its action accords with the basic direction of Metal. By descending, it is able to carry the relationship of Metal to Wood.
This basic and essential dynamic helps us to understand literally all of Zhishi’s abilities, and its role in the dozens of classical formulas it occurs in.
We can conceptualize Zhishi as affecting the Gallbladder, or the various organs and tissues belonging to Yangming. We can remember that it treats various bindings and knottings of qi, and we can also consider its effect on substances like phlegm. All these ways of conceptualizing its action are useful in various contexts, but they are all derived from understanding the basic direction and dynamic of Zhishi. That directional dynamic is completely described by the statement that Zhishi is the Wood of Metal.
Grasping this principle and applying it in a fluid way enables us to use Zhishi clinically, and it also demonstrates the elegance and power of a classical approach to herbalism.
Look for my next article in a week, exploring the next herb of the metal class – Dandouchi, fermented soybean! Yum!