Picking up on the discussion of seasons and how they relate to Traditional Chinese Medicine (TCM), I’ll talk a little today about how Spring is considered to be aligned with the element/phase (行/Xíng) of W
ood, and how both of these connect to the Liver organ system.
Wood is Alive
TCM conceives of the element of Wood as a living thing, like a tree, and more specifically the tendency of trees to grow ‘up and out’ as branches stretch up into the sky, reaching towards that supreme source of Yang, the Sun. It may even be useful to conceive of “Wood” meaning something more like “Growth” or “Reaching”, which is in keeping with the translation of 行/Xíng as more akin to “phase” or “movement” than “element”. So it’s fairly easy to see how the movement of growth, as a reaching upward, is illustrated by trees and other plants, and how this action is associated with Spring, the time that growth begins again as trees grow new buds and leaves, and seeds sprout to grow entirely new plants. But what does this have to do with the Liver?
Liver is Gentle Yang
When we consider the 5-Elements, we often describe them as having a Yin or Yang like quality. Previous posts have described Extreme Yang/Lesser Yang as being likened to the nature of Fire (Extreme) and Wood (Lesser, or Gentle) Yang elements. This helps us to understand why the Liver is associated with the Gentle Yang principle.
Yang tends to move ‘up and out’ (as opposed to ‘down and in’, which would be Yin), so the most ‘up and out’ organ is called Extreme Yang, and the Heart fits this description the best in the body according to TCM principles: it is in the upper part of the body, it is in constant motion, it pumps blood ‘up and out’ (yes, and down, but only after the aorta curves downward!); all very Yang activities. The Liver is considered the next most Yang organ in nature, and I’d like to suggest two main reasons for this.
1. The Liver and Blood
Although the liver doesn’t actively pump blood vigorously like the heart, it does filter the blood and moves it more gently ‘up and out’ as all blood is eventually routed through the portal vein system. Also called more specifically the “hepatic portal vein” (hepatic = of the liver), this is a system of blood vessels where all blood from the gastrointestinal system is carried to the liver, where it is filtered, and then passed on to the systemic circulation of the rest of the body, or ‘up and out’. Ancient physicians examining the liver may have seen a similar structure between the heart and the liver as regards large vascular systems going to and from these organs, and theorized a connection between the heart and liver function for this reason as well.
This modern explanation of liver function demonstrates a major role of the Liver according to TCM, which is to “store Blood”, as well as to control the distribution of Blood to the right places at the right times.
2. The Liver in the Lower Burner
Without getting into too much detail, because the subject is worth several blog posts (at least) to adequately explain it, TCM divides the torso into three main levels: upper, middle, and lower, and calls these three regions the Triple Burner/三焦/Sān Jiāo.
The liver is located right below the diaphragm, which might make you think that it fits in the middle burner, however, the Spleen and Stomach are considered to be in the middle burner, and so in TCM we actually talk about the Liver (and the Kidneys) as being the principle organs in the lower burner… which, again, worthy of at least several blog posts to explain the nuances of this… but for now, just trust me it all makes sense!
So the Liver has this rather Yang function of filtering and controlling the flow of blood ‘up and out’ but it is located in the lower part of the body. Its physical location in the lower half/lower third of the body therefore makes it less Yang than the Heart, which is located in the upper half/upper third.
Gentle Yang, Spring Time, and Growing Wood
So, to sum up: for various reasons, the Liver is considered by TCM to be the Gentle Yang organ in function, and so it is associated with the Gentle Yang element which is Wood. The gently ‘upward and outward’ reaching of Wood as it grows is associated with the activity of plants in Spring time, both older plants growing new buds, leaves, and branches, and newly sprouted seeds beginning to awaken and reach for sunlight.
Questions? Feel free to email me at firstname.lastname@example.org, I’m happy to talk about all these things pretty much any time. Feel free to suggest a topic for a blog post as well, and I promise to get to it faster than I would if left to my own slow devices 😉