Know Your Yin & Yang

Yin & Yang

Yin and Yang in Chinese philosophy represent opposites but complementary qualities. Each phenomenon could be described as Yin or as Yang, in relation to another phenomenon.

The Chinese characters for “Yin” and “Yang” are related to the dark and sunny side of the hill. By extension, they therefor also indicate “darkness” and “light” or “shady” and “bright”.

Two phases of a cyclical movement

The alternation between Yin and yang is essentially an expression of every phenomenon in the universe alternating through a cyclical movement. Day changes into night, summer into winter, growth into decay and vice versa. Every phenomenon contains within itself both Yin & Yang in different degrees of manifestation.

Yang	Yin
Light	Darkness
Sun	Moon
Brightness	Shade
Activity	Rest

Two stages of transformation

Yang symbolizes the more immaterial, rarefied states of matter, whereas Yin symbolizes the more material, dense states of matter, i.e Water in its liquid state pertains to Yin, and the vapor resulting from heat pertains to Yang. In its purest and most rarefied form, Yang is totally immaterial and corresponds to pure energy, and Yin, in its coarsest and densest form, is totally material and corresponds to matter. From this viewpoint, energy and matter are but two states of a continuum, with an infinite possible number of states of aggregation.

As Yang corresponds to creation and activity, it naturally also corresponds to expansion and it rises. As Yin corresponds to condensation and materialization, it naturally also corresponds to contraction and it descends.

The relationship and interdependence of Yin and Yang are represented in the famous symbol “Tai Ji” (Supreme Ultimate):

1. Although opposites, Yin & Yang form a unity and are complementary.
2. Yang contains the seed of Yin and vice versa. Therefor nothing is totally Yin nor totally Yang
3. Yang changes into Yin and vice versa

Yang	Yin
Immaterial	Material
Energy	Form
Generates	Grows
Non-substantial	Substantial
Expansion	Contraction
Rising	Descending
Above	Below

Four aspects of Yin & Yang relationship

1. The opposition of Yin and Yang – Yin and Yang are opposite stages of a cycle or of states of aggregation. Nothing in the natural world escapes this relative opposition. Everything only pertains to Yin or Yang in relation to something else.
2. The interdependence of Yin & Yang – although Yin & Yang are opposite, they are also interdependent: one cannot exist without the other.
3. Mutual consumption of Yin & Yang – Yin & Yang are in a constant state of dynamic balance:
   1. When yin is predominant, it induces a decrease of Yang
   2. When Yang is predominant, it induces a decrease of Yin
   3. When Yin is weak, Yang is in apparent excess
   4. When Yang is weak, Yin is in apparent excess
4. The inter-transformation of Yin & Yang – Yin & Yang are not static, but actually transform into each other. This change does not happen at random, but only at a certain stage of development of something. Summer changes into winter, day into night, life into death and vice versa. Change only takes place when the internal conditions are ripe and when the time is ripe. Day cannot turn into night at any time, but only when it has reached its point of exhaustion.

Since Yang in nature represents activity, light, warmth it logically represents energy/warming faculty in the human body. Since Yin in nature represents stillness it translates into the material aspect of the human body. In other words Yin represents matter, blood, body fluids, while Yang is the force that makes them come to life.

There is good health when Yin and Yang are in balance (i.e. energy and matter are in balance). When there is deficiency of Yang, Yin instantly becomes excessive and vice versa – when there is deficiency of Yin, Yang becomes excessive. Yang deficiency means that the energy/warming principle of the organ is deficient leading to “excess matter”, i.e. sluggishness, lethargy, overflow. Vice versa – Yin deficiency means that the matter of the organ is deficient leading to excess energy. If this excess energy remains for a longer period of time it will transform into heat. Thus Yin deficiency leads to heat accumulation.

Application of Yin & Yang to medicine

The whole of Chinese medicine, its physiology, pathology, diagnosis and treatment, can all be reduced to the basic and fundamental theory of Yin & Yang. Every physiological process and every symptom or sign can be analyzed in the light of the Yin & Yang theory. Ultimately, every treatment modality is aimed at one of these four strategies:

1. To tonify Yang
2. To tonify Yin
3. To eliminate excess Yang
4. To eliminate excess Yin

Yin & Yang in body structure:

Yang	Yin
Superior	Inferior
Exterior	Interior
Posterior-lateral surface	Anterior-medial surface
Back	Front
Function	Structure
Head	Body
Above waist	Below waist

Yin & Yang organs

Some organs pertain to Yin and some to Yang. The Yang organs are constantly filling and emptying, transforming, separating and excreting the products of food in order to produce Qi. They are in contact with the exterior through the mouth, anus or urethra. The Yin organs store the pure essences (Qi, Blood, Body Fluids and Essence) extracted from food by the Yang organs.

Qi – Blood

Qi is Yang in relation to Blood. Blood is also a form of Qi: it is a denser and more material form of Qi, and therefore more Yin.

Qi has the function of warming, protecting, transforming and rising, all typically Yang functions. Blood has the function of nourishing and moistening, all typically Yin functions.

Defensive Qi – Nutritive Qi

Defensive Qi is Yang in relation to nutritive Qi. Defensive Qi circulates in the skin and muscles (a Yang area) and has the function of protecting and warming the body (a Yang function). Nutritive Qi circulates in the internal organs (a Yin area) and has the function of nourishing the body (a Yin function).

Oppositions of Yin & Yang

Yang	Yin
Fire	Water
Hot	Cold
Restless	Quiet
Dry	Wet
Hard	Soft
Excitement	Inhibition
Rapidity	Slowness
Transformation, change	Conservation, storage, sustainment

Main clinical manifestations of Yin & Yang:

Yang	Yin
Acute disease	Chronic disease
Rapid onset	Gradual onset
Rapid pathological changes	Lingering disease
Heat	Cold
Restlessness, insomnia	Sleepiness, listlessness
Throws off bedclothes	Likes to be covered
Likes to lie stretched	Likes to curl up
Hot limbs and body	Cold limbs and body
Red face	Pale face
Likes cold drinks	Likes hot drinks
Loud voice, talks a lot	Weak voice, dislikes talking
Thirst	No thirst
Scanty dark urination	Profuse pale urination
Red tongue with yellow coating	Pale tongue
Superficial pulse	Deep pulse

Differential Diagnosis of Heat and Cold

Understanding the basic terminology and principles of Yin & Yang diagnosis allows us to unravel complicated patterns and identify the basic contradictions within them, reducing the various disease manifestations to the bare relevant essentials. The purpose of applying the principles of diagnosis is not only to categorize the disharmony, but to understand its genesis and nature, enabling to decide on a treatment for a particular disharmony.

Yin & Yang are the fundamental terms of Chinese medicine for expressing imbalance of heat and cold. Excess of either Yin or Yang will present itself differently, depending if the excess is full or empty:

Full heat means Yin is intact, and Yang is excess.

Empty heat means Yang is intact, and Yin is deficient.

Full cold means Yang is intact, and Yin is excess.

Empty cold means Yin is intact, and Yang is deficient.

Full Heat

The main general manifestations possible for interior full heat are fever, thirst, red face, red eyes, constipation, offending smell of the feces, urine or sweat, scanty-dark urine, a rapid full pulse, a red tongue with yellow coating. Other signs may be red skin eruptions which feel hot, any type of burning sensation (such as in cystitis or gastritis). Any loss of blood with large quantities of bright-red blood indicates heat in the blood. As far as the mind is concerned, any condition of extreme restlessness or manic behavior indicates heat in the heart.

Common causes for full heat may be the aggravation of a hot constitution, the consumption of hot energy foods or long standing emotional problems, when the stagnation of Qi generates heat. Full heat can also develop from the invasion of an exterior pathogenic factor which turns into heat once in the body.

Empty Heat

Empty Heat arises from deficiency of Yin, when Yin is consumed the Yang is relatively in excess. The main general manifestations possible for Empty Heat are afternoon fever or feeling of heat afternoon, a dry mouth, a dry throat at night, night sweating, a feeling of heat in the chest and palms and soles, dry stools, scanty-dark urine, a floating-empty and rapid pulse and a red peeled tongue. Empty Heat can easily be recognized from a typical feeling of mental restlessness, fidgeting and vague anxiety.

Empty Heat frequently arises from deficiency of Kidney-Yin, because Kidney-Yin is the foundation for all the Yin energies of the body and can affect the Yin of the Liver, Heart and Lungs.

Full Cold

The main general manifestations possible for Full Cold are chilliness, cold limbs, no thirst, pale face, abdominal pain aggravated with pressure; desire to drink warm liquids, loose stools, clear-abundant urination, deep-full-tight pulse and a pale tongue with thick white coating. Cold contracts and obstructs and often causes pain, especially abdominal pain. Interior Full Cold can arise from direct invasion of exterior cold into the interior; in particular, exterior cold can invade the Stomach causing vomiting and epigastric pain, the intestines causing diarrhea and abdominal pain and the uterus causing dysmenorrhea. All these conditions have an acute onset.

Empty Cold

Empty Cold arises from the deficiency of Yang. Empty Cold develops when Yang Qi is weak and fails to warm the body. It is mostly related to Kidney-Yang and Spleen Yang deficiency, and also possibly to Heart Yang or Lung Qi deficiency. The main general manifestations possible for Empty Cold are chilliness, cold limbs, a dull pale face, no thirst, listlessness, sweating, loose stools, clear abundant urination, a deep-slow or weak pulse and a pale tongue with thin white coating.