Since this newsletter is primarily concerned with the Kidneys, and as the Kidneys are primarily concerned with Yin-Yang physiology, it is necessary to at least briefly discuss what Yin and Yang mean. I plan to discuss these more extensively in a future article.
Yin and Yang are simply the named recognition of dualistic reality. We can only experience life, and reality, through dualism. There is no day without night, no up without down, no hot without cold. All opposites exist in complementary relation to one another, and it is only through our perception that we experience them as separate. On and off, 0 and 1. There, now you have the entire concept of binary language and the foundation of computers.
I have purposely tried to use words and terms which reflect this concept throughout this newsletter. Salt and sugar, adrenal cortex and adrenal medulla, sodium and chloride, positively charged ions and negatively charged ions. To continue further with regards to physiology, Yin is the fluids aspect of the Kidneys and Yang is the metabolic aspect. Yin is water, Yang is fire. Yin is the interior of the body, Yang is the exterior. Yin is structure, Yang is function. Yin is estrogen, Yang is progesterone. It is most important to understand that Yin and Yang are never absolutes. You cannot go to the store and purchase a Yin. They are relational to one another. The front of the body is Yin relative to the back of the body, but the chest is Yang relative to the abdomen, which is relatively more Yin. Even the concept of absolute and relative is a Yin-Yang dichotomy. In fact, by definition, any concept is a Yin-Yang dichotomy. Anything which we can speak of or experience must be so because we experience it in relation to something else. Yin-Yang is the fundamental Chinese expression of manifestation in the world.
One critical concept to understand is that the interpenetration of Yin and Yang is what defines and drives life. In life, they remain mixed. In disease and ultimately death, they separate.