Written by Jeonghwa Lee, Choonjae Lee, Published by Korea Institute of Oriental Medicine
Essence, qi, spirit, blood, and fluid and humor are the basic constituents of life in TKM. Essence is the fundamental substance that builds up the physical structure and maintains bodily function. Spirit is the life-purifying mind. Qi is the life energy that flows within the human body as well as to its functional activities. Blood is the extended concept of biological substances which includes blood, a red fluid which circulates through the blood vessels, that nourishes and moistens the
whole body. Fluid and humor is a general term for all kinds of normal fluid in the body, except the blood.
1. Essence
TKM regards essence as the basic building block of the human body and the driving force of life activities. Innate essence refers to that inherited from parents at birth, whereas acquired essence means the essential nutrients that are digested and absorbed from food. Therefore, essence is fundamental for a human being to lead a human life.
1) Functions of Essence
a. Essence governs reproduction and growth.
When a human being is conceived, essence given by the parents is formed in the human being. Based on this essence and nutrients supplied from the mother’s body, the human being begins the formation of the brain, bone, muscle, skin, flesh, and hair. In other words, essence is the essential substance that exists before the human body differentiates into brain, bone, muscle, skin, flesh, and hair. The following is an excerpt from Hwangjenaegyeongsomun (Chinese Medical Text Called Inner Canon of Yellow Emperor). It indicates how essence governs the growth and development of the human body.
The stages of a woman’s life (age increases by a factor of 7)
- At age 7(7*1), milk teeth are replaced and hair grows as the kidney qi flourishes;
- At age 14(7*2), starts menstruation as the conception vessel begins to flow;
- At age 21(7*3), growth reaches its peak;
- At age 28(7*4), bones and sinews turn solid, the hair growth peaks, and body matures; Women aged between 21 and 28 are in the healthiest state and at a marriageable age;
- At age 35(7*5), complexion loses some of its radiance and hair begins to shed;
- At age 42(7*6), complexion loses all of its radiance and hair turns gray;
- At age 49(7*1), stops menstruating and becomes sterile as the conception vessel becomes deficient. The stages of a man’s life (age increases by a factor of 8)
- At age 8(8*1), milk teeth are replaced and hair grows as the kidney qi flourishes;
- At age 16(8*2), begins to have wet dreams and consequently the essential qi goes out. As the balance of yin and yang is achieved, the man becomes potent;
- At age 24(8*3), muscles and sinews become solid and growth reaches its peak; At age 32(8*4), muscles and sinews become the strongest, and the growth of the flesh peaks;
Therefore, men aged between 21 and 32 are at a marriageable age.
- At age 40(8*5), starts to shed hair and the teeth grow weaker as the kidney qi weakens;
- At age 48(8*6), complexion loses some of its radiance and hair turns gray as the yang qi weakens;
- At age 56(8*7), muscles and the body become weaker as essence runs dry;
- At age 64(8*8), begins to lose teeth or hair. Essence, as is seen, plays a critical role in the growth and development of human beings.
b. Essence enlivens the brain.
This means that essence is physical fundamental to the mental activities of human beings.
c. Essence is associated with the preventive capacity against diseases.
Essence expresses abundant vitality or represents vital materials. It serves as the prevention against the pathogenic qi which causes diseases. In other words, the abundance of energy strengthens vitality and adaptability, which make it hard for pathogenic qi to infiltrate into the body. The lack of energy, however, weakens vitality and adaptability, opening the way for pathogenic qi to infiltrate into the body and resulting in frequent incidence of diseases.
2. Qi
1) Classification of Qi in TKM
a. Ancestral qi: Ancestral qi is stored in the chest and serves as the dynamic force of blood circulation, respiration, voice, and bodily movements. It is also referred to as pectoral qi.
b. Defense qi: Defensive qi moves outside the vessels, protecting the body surface and warding off external pathogens.
c. Nutrient qi: Nutritive qi moves within the vessels and nourishes all the organs and tissues.
d. Visceral and bowel qi: Visceral and bowel qi enables the viscera and bowels to perform their activities. To be more specific, it can be classified into liver qi, heart qi, spleen qi, lung qi, stomach qi, gallbladder qi, etc., according to the five visceral and six bowels.
e. Middle qi: Middle qi refers to the qi of the middle energizer.
f. Meridian qi: Meridian qi flows through the meridians and is also called collateral qi.
g. Pathogenic qi: Pathogenic qi leads to diseases of the human body. It is classified into cold qi, damp qi, hot qi, fire qi, dry qi, etc.
h. Healthy qi: Healthy qi is a combination of the innate qi and the acquired qi and serves as the physical substrata and dynamic force of all vital functions
2) Functions of Qi
a. Promoting: Qi promotion refers to the function that provides the active, vital essence necessary for the growth and development of the human body and performs the physiological functions of the organs, meridians and tissues. In addition, qi promotes the formation and circulation of blood and supports the metabolism of body fluid. If there is a deficiency of qi, its promoting functions are weakened.
b. Defending: Qi resists the entry of pathogenic qi into the body, defends against its attack and maintains healthy physiological functions.
c. Containing: Qi consolidates and retains the body’s substances and organs by holding everything in its proper place. This function controls blood and stops it from overflowing out of the blood vessel. It also controls urine, sweat, and seminal fluid and manages their moderate discharge out of the body.
d. Warming: Qi contains heat energy for the body. It warms the body and keeps it at a constant temperature so normal physiological functions can take place.
e. Transforming: Qi has a transformation function, which is important for the metabolism of fundamental substances. This function transforms substances in the body into essence or vital energy. For example, certain actions of qi allow food to be changed into food essence, which is in turn transformed into different types of qi and blood. Indigestible food and waste are also transformed by qi into urine and stools for excretion.
Depending upon its origin, location, and function, qi is named differently. Whatever name it may be given, each is closely related, combined and complemented to one another.
3. Spirit
In a narrow sense, spirit refers to mental activities, referring to mentality, consciousness, thinking and feeling such as ethereal soul, mind, ideation, corporeal soul and will. In a broad sense, spirit refers to vital activities, including the regulation of the appearances of the physiological conditions present in the body. Spirit is very important for visual examination, and is one of the major criteria for diagnosis. Abundant spirit represents active and favorable functions of the five viscera, while dispersed spirit shows the lack of energy inside the viscera and unfavorable condition.
