TCM Theory: The Concept of Qi



    * The concept of Qi
    * Formation of Qi
    * Functions of Qi
    * Basic patterns of Qi's movements
    * Classification of Qi

Qi, Blood and Body Fluids are the most basic substances that constitute the human body and maintain its functional activities. They are, on the one hand, the products of the functional activities of the Zang and Fu Organs of the body, and on the other hand, the material basis of these functional activities. As TCM holds that the life process is, in fact, a process of the metabolism of these substances, this is regarded as the true meaning of the Zang and Fu Organs. In other words, the viscera are produced and maintained by the activities of these substances. Therefore, disorders of the viscera can be generalized as those of these substances.

Generally speaking, Qi is an essential substance that is full of vigor and flows fast. Blood is the red liquid circulating in the vessels and nourishing the whole body, and Body Fluids are a general term for all the water necessary for life. Qi is attributed to Yang, because it is mobile and functions to move and warm; while the Blood and Body Fluids are attributed to Yin because they are motionless and function to nourish and moisten the human body. In this sense, Qi is also named Yang Qi and the Blood and Body Fluids, Yin Fluids of the body.

1. The Concept of Qi
Concept of Qi Qi was originally a philosophic concept. The ancients believed that the world changes and things in the world can transform from one to another, so when they tried to explain the world with a common substance, they determined that the substance must have two properties: invisibility and motion. As it is invisible or has no certain shape, it can create various kinds of things; and as it is moving, things in the world are always changing and may transform from one to another. Air, the original meaning of Qi, is just such a substance which cannot be seen but the movement of which, as wind, can be felt. This was extended to mean that the most basic substance of the world, and its movement and change can explain the generation, development and change of all things in the world.

The ancient Chinese philosophy holds that Qi is this most basic substance constituting the world. Accordingly, TCM also believes that Qi is the most fundamental substance in the construction of the human body and in the maintenance of its life activities. As a whole, Qi in the cosmos takes two patterns of existence, diffused Qi and coagulated Qi. The former is more vigorous, cannot be detected directly and exists everywhere. The latter is manifested as various kinds of things that can be seen or that have certain shapes. In order to survive, coagulated Qi must communicate with diffused Qi and its generation as well as its ending results from movement of the diffused Qi. That means, when the diffused Qi coagulates, it creates substantial matter, while if it separates, the matter disappears. Therefore, any substantial matter can be regarded as a special process of the movement of Qi, and life, in essence, is the course of Qi's ascending, descending, exiting and entering movements in given conditions.

Man depends on nature for his production and growth and must observe the common laws of the world. As everything in the world comes from the interaction of Heaven Qi and Earth Qi, man must breathe to absorb Heaven Qi and eat to absorb Earth Qi. The food Essence transformed and transported by the Spleen must be sent up to the Lung to combine with fresh air to produce the nutrients necessary for man's life activities.

Qi of the human body also has two patterns of existence. The coagulated Qi is manifested as various visible or structural components of the body, such as viscera, body figure, sense organs, Blood, Body Fluids and Essence; the diffused Qi is manifested as the Qi that flows in the body, but takes no certain form, such as Nutritive Qi, Defensive Qi, Primordial Qi and Pectoral Qi.

2. Formation of Qi
Qi of the human body comes from the combination of three kinds of Qi, Primordial Qi inherited from parents, the fresh air inhaled by the Lung and the refined food Essence transformed by the Spleen. Primordial Qi is derived from the Congenital Essence of the parents and is the primary substance to produce an embryo. So it forms the basis of the human body and its life activities. Without Congenital Essence, there can be no human body. After birth, the congenital Essence is stored in the Kidney to promote development and to control the reproductive activity of the human body. The refined food Essence is generated by the food which is taken in after birth and is distributed all over the body to produce nutrients and Qi and Blood under the action of the Spleen and Stomach. Fresh air is inhaled by the Lung after birth and is the main source of Qi of the human body.

From the process of formation of Qi, we can see that Qi of the human body is closely related to the functional activities of the Kidney, the Spleen and Stomach, and the Lung, in addition to the congenital constitution, food and nutrients, and the environment. Only when these organs function properly can the Qi of the body flourish. Conversely, dysfunction of any of these organs will influence the formation of Qi and the physiological function of Qi. For example, dysfunction of the Lung will weaken respiration, leading to failure of fresh air to be inhaled and the turbid Qi of the body to be exhaled, with the resultant inadequate formation of Qi.

The transformation and transportation of the Spleen and Stomach play a particular role in the formation of Qi, for man relies on the nutrients transformed and transported by the Spleen and Stomach for his life after birth. On the one hand, the Spleen sends up nutrients to the Lung to be dispersed, on the other, it sends down nutrients to the Kidney to supplement Kidney Essence. So, hypofunctioning of the Spleen and Stomach influences all three elementary substances that produce Qi.

3. Functions of Qi
Generally speaking, Qi of the human body has five functions: pushing, warming, defending, controlling and steaming.

3-1. Pushing
Qi is a vigorous substance that flows fast in the human body. So it promotes the growth and development of the body, the movement, distribution and discharge of Blood and Body Fluids, and the functional activities of Zangfu Organs.

After birth, the Genuine Qi generated from Kidney Essence determines the growth and development of the human body. After middle age, Genuine Qi gradually declines, so a person grows old. If his Genuine Qi is deficient, a person's development will be poor.

The physiological functions of Zangfu Organs and Channels and Collaterals of the human body all depend on the pushing of Qi as well as the nourishing of Blood. The vigor and the ascending, descending, entry and exit movements of Qi play a very important role in promoting the functional activities of Zangfu Organs and Channels and Collaterals. Any organ is a place where the activities of Qi take place, so the physiological effect is in fact, the manifestation of Qi's movements. For example, the respiration of the Lung is actually carried out by the dispersing and descending effects of Lung Qi. Therefore, when Qi is deficient, hypofunctioning of Zangfu Organs will ensue. For instance, deficient Lung Qi often leads to feeble breathing, a lower voice, lassitude, weak pulse, etc.

Qi also promotes the generation, distribution and discharge of the Blood and Body Fluids. As Yin substances, Blood and Body Fluids depend on Qi's activities to be generated. In other words, generation of these substances relies on the activities of Qi of the Spleen and the Stomach, the Lung and the Kidney. Besides, Qi is a vigorous substance, so it can activate the flow of Blood and Body Fluids, as well as transform them into various secretions and excretions. For this reason, Qi Deficiency often leads to an impeded flow of Blood or stagnation of Blood, or retention of Body Fluids in the body, which, in turn, causes Phlegm or edema.

3-2. Warming
Qi, as a Yang substance, is rich in heat, which can warm Zangfu Organs, Channels, skin, and muscles and tendons, to maintain normal body temperature and the normal functional activities of these organs and tissues. Motion produces heat, so the heat carried by Qi is in fact, a result of the constant movement of Qi, and the body temperature is maintained by the constant movement of Qi. In addition, Qi's warming function contributes to the movement of Blood and Body Fluids. The ancients observed that water in a river would flow in warm weather and freeze in cold weather, so they drew the conclusion that the warming effect of Qi must be an imperative condition for the free flow of Blood and Body Fluids within the body.

Pathologically, disorders of Qi in its warming function are mainly manifested as two kinds: one is a cold manifestation due to Deficiency of Qi, which results mostly from the deficient Qi failing to produce adequate Heat to warm the body, marked by aversion to cold and a desire for warmth, cold limbs, lower body temperature and sluggish flow of Blood and Body Fluids. The other is the manifestation of Heat due to stagnation of Qi, which is usually caused by sluggish flow of Qi in a local area.

3-3. Defending
The defensive ability of the body results from the combined action of a number of physiological functions, of which the function of Qi plays a particularly important role. The defensive effect of Qi mainly indicates that Qi can prevent the invasion of external pathogenic factors into the body. Generally speaking, external pathogens invade the body through either the skin or the nose and mouth. Defensive Qi functions to protect the body surface, and control the opening and closing of the pores, so it can prevent the invasion of external pathogens. If the defensive function of Qi is deficient, the resistance of the body against the invasion of these factors will be weakened, and as a result, susceptibility to such diseases as the common cold are likely to occur.

3-4. Controlling
Qi has the function of controlling the flow of Blood and Body Fluids to prevent extravasation or unnecessary loss of Body Fluids. Qi can keep the Blood flowing within the vessels to avoid extravasation, control the amount and time limit of such secretions as sweat, urine, gastric juice, and saliva to prevent their excessive loss, and control emission to avoid its excessive discharge. When Qi is deficient, Yin Fluids will be profusely lost. For example, failure of Qi to control Blood will cause various kinds of bleeding; inability of Qi to control Body Fluids will cause spontaneous sweating or profuse sweating, incontinence of urine or profuse urine; and failure of Qi to control emission will cause nocturnal emission, premature ejaculation, or seminal emission.

The controlling effect of Qi and the pushing effect of Qi are opposite and supplement each other. On the one hand, Qi promotes the distribution and discharge of Blood and Body Fluids; on the other, Qi controls the flow of these Yin substances to prevent their unnecessary loss. Only when these two opposite aspects are harmonized can the normal flow and discharge of the Yin substances and the metabolism of Blood and water be maintained.

3-5. Transforming
This refers to various conversions occurring along with the movement of Qi. It includes the changes of Qi during its movement and the generation and metabolism of Essence, Blood and Body Fluids and their transformation. That is to say, any changes of substances can be considered the result of the transforming effect of Qi, such as transformation of Food into nutrients and wastes, that of wastes into feces, that of nutrients into Qi and Blood, that of Body Fluids into sweat and urine, and the discharge of urine and feces. As the transforming effect of Qi in the human body is a process in which the metabolism of the substances take place, it forms the essence of life.

Although the above mentioned five functions of Qi differ from each other, they are all based on the basic property of Qi, or the vigorous and nutritive nature of Qi.



4. Basic patterns of Qi's movement
Qi flows throughout the whole body because of its strength and vigor. The movement of Qi is called Mechanism of Qi, which can be generalized as four aspects: ascending, descending, entering and exiting movements, which are based on directions. Ascending refers to the upward movement of Qi from a lower area; descending means the downward flow of Qi from an upper area. Exiting means the outward movement of Qi, and entry indicates the inward movement of Qi. Although the activities of the human body are multiple, they can all be summarized as these four aspects. For example, the dispersing effect of the Lung is a manifestation of the exit and ascent of Qi, while its descending effect is a manifestation of the descending and entering movements of Qi.

The physiological function of Zangfu Organs is often reflected on their Qi's ascent, descent., entry and exit movements. Take the Spleen and Stomach for example. The food that enters the Stomach is separated as nutrients and wastes after digestion. The nutrients are then absorbed and transported to each part of the human body through the activities of Spleen Qi, which is mainly marked by ascent and exit. On the other hand, Stomach Qi functions downward to send down the wastes as well as urine and stools, indicating that it goes downward in physiological conditions. Take the Kidney for another example; the Kidney is located in the Lower Jiao, but Genuine Qi manufactured by Kidney Essence has to go upward so that It can be distributed all over the body. This is a manifestation of ascent. On the other hand, the Kidney can assist the Lung by its receiving function, so it also has the manifestation of descent.

The ascent, descent, exit and entry movements of Qi are of prime importance in human life. The Kidney Essence, the food Essence transported and transformed by the Spleen and Stomach and the fresh air inhaled by the Lung, will not be distributed over the body to perform their physiological functions if they do not make ascent, descent, entry and exit movements.

Entry, exit, ascending and descending movements of Qi must be kept in harmony. In other words, the two opposite aspects should be balanced. A free flow of Qi as well as balancing the ascent, descent, and exit and entry movements of Qi are known as the harmony of activities of Qi. Once this harmony is destroyed, disharmony of the activities of Qi will ensue, which mainly consists of five states: adverse upward flow of Qi, collapse of Qi, escape of Qi and obstruction of Qi in its outward passage. The adverse upward flow of Qi refers to excessive ascent or insufficient descent of Qi, which affects the Liver, the Lung and the Stomach in most cases. As Liver Qi tends to go up, any induction factors may cause uprising of Liver Qi; Lung Qi and Stomach Qi, in a normal case, tend to go downward, so when the pathway for descent is obstructed, their Qi will go upward instead. The former case is a result of excessive ascent of Qi, while the latter is a result of inadequate descent of Qi. Collapse of Qi results mostly from excessive descent or inadequate ascent of Qi, which occurs mainly in the Spleen. As Spleen Qi functions upward to send up nutrients, it may sink if it is deficient. Escape of Qi indicates inability of Qi to be kept within the body which leads to excessive loss of Qi, which often follows profuse sweating or severe hemorrhage. Obstruction of Qi in going outward is usually caused by an attack of noxious gases which obstruct the pathways for Qi in the Interior of the body to go out. Such a case is marked by sudden occurrence of coma or syncope. The last type is stagnation of Qi, meaning impeded flow of Qi in the whole body or in a local area.

5. Classification of Qi
As the most basic substance that constitutes the world, Qi can be used to name everything in the world, so it is hard to classify it. However, Qi mentioned here is something concrete, or Qi that is different from Blood and Body Fluids. That means, it is not a gen eral term for all the components of the body, but substance that has a certain distribution and function. Clinically, the following four kinds of Qi are most the commonly mentioned.

5-1. Primordial Qi
Primordial Qi is also named Genuine Qi. It is manufactured by Kidney Essence and functions as the primary motive force for the growth and development of the human body, as well as the functional activities of Zangfu Organs. After being manufactured, it goes through the whole body by the way of the San Jiao to promote the life activities.

The main function of Primordial Qi is to initiate and promote the vital activities. The growth and development of the human body, and the functional activities of Zangfu Organs all depend on Primordial Qi. Therefore, when Primordial Qi is sufficient, the functional activities of Zangfu Organs will be strong and the constitution will be good. However, if Primordial Qi is deficient due to a congenital defect or improper feeding after birth, the functional activities of the whole body will become weakened.

It must be pointed out that the mutability of Primordial Qi is not only determined by the congenital Essence, but also determined by the acquired Essence or the Food Essence sent down to the Kidney. So congenital Deficiency of Primordial Qi can be corrected to some extent by supplementing the acquired Essence, or by strengthening the function of the Spleen and Stomach to promote the production of Food Essence. Long-standing diseases, which often consume the Essence of the human body, may lead to Deficiency of Primordial Qi.

5-2. Pectoral Qi
Pectoral Qi is also termed Great Qi. It accumulates in the thorax where Qi of the whole body converges. So the thorax is also known as "the sea of Qi".

Pectoral Qi is generated by the combination of the food Essence the Spleen transports and transforms and the fresh air in haled by the Lung. Therefore, the functional states of the Spleen and the Lung directly influence the formation of Pectoral Qi.

Pectoral Qi is distributed in the thorax after its formation, then to the Blood vessels and the respiratory tract. Its main functions are twofold: first, it can assist the Lung in breathing. As Lung Qi serves as the force for breathing and voice, speaking, voice and respiration are all closely related to the quality of Pectoral Qi. Usually, clear speech, a strong voice and moderate and rhythmic respiration indicate strong Pectoral Qi, while unclear speech, a feeble voice and shallow breathing or shortness of breath are signs of Deficiency of Pectoral Qi. Second, Pectoral Qi can assist the Heart in activating the flow of Blood. So, circulation of Qi and Blood and the pulsation of vessels can reflect its condition. Generally speaking, when Pectoral Qi is sufficient, the pulse will be moderate and forceful, and the Heart will beat rhythmically and evenly. If Pectoral Qi is deficient, the pulse will be swift, irregular, feeble or scattered.

Pectoral Qi is usually considered a link connecting the functional activities of the Heart and those of the Lung. In the clinic, Deficiency of Pectoral Qi in most cases indicates Deficiency of Lung Qi leading to Deficiency of Heart Qi and ensuing Blood Stasis. For example, when a patient suffering from chronic bronchitis develops pulmonary Heart disease, which is marked by shortness of breath, a low voice, palpitation, a purplish face, running or intermittent pulse, etc. , he or she can be diagnosed as having deficient Pectoral Qi.

5-3. Nutritive Qi
Nutritive Qi is the Qi flowing in the Blood vessels. It is so named because it is rich in nutrients. As it exists together with the Blood in the vessels, they are often collectively named Ying Blood (Ying means Nutritive Qi here).

Nutritive Qi is formed by the combination of the nutritious part of the food Essence transported by the Spleen and fresh air inhaled by the Lung. After its formation, Nutritive Qi is sent to the Channels to flow in the order of the Twelve Regular Channels.

The main functions of Nutritive Qi are to generate Blood and to nourish the whole body. In TCM, Blood consists mainly of two parts: Nutritive Qi and Body Fluids. The Nutritive Qi can absorb Body Fluids from refined food and carry it to the vessels to form Blood. So Nutritive Qi has the function of generating Blood. Moreover, all Zangfu Organs, Channels and tissues depend on the nourishment of Nutritive Qi for their existence and functional activities. As Nutritive Qi, compared with Defensive Qi, belongs to Yin it functions chiefly to nourish the physique of the body.

5-4. Defensive Qi
Defensive Qi is Qi that functions to defend the human body. It is also named Defensive Yang, because it belongs to Yang compared with Nutritive Qi.

Defensive Qi comes from refined food that is vigorous and flows fast, and fresh air inhaled from Heaven. Being vigorous, Defensive Qi cannot tolerate the control of the vessels, so it flows out of the vessels. The distribution of Defensive Qi has two features: the flow following Nutritive Qi and free flow. The former indicates that Defensive Qi also goes along the Twelve Regular Channels, while the latter indicates that Qi is distributed all over the body.

The main functions of Defensive Qi include three aspects: First, protecting the body surface from the invasion of external pathogens. Defensive Qi permeates the muscular striae and the skin to control opening-closing of the muscular striae, so it acts as a defense against the invasion of external pathogens. If Defensive Qi is deficient, diseases due to the attack of external pathogens are likely to occur. Second, warming and nourishing Zangfu Organs, skin and hair, muscles, etc. , to maintain the normal body temperature and ensure the normal activities of the organs and tissues. When Defensive Qi fails to warm due to its Deficiency, cold symptoms may be exhibited. On the other hand, stagnation of Defensive Qi will produce Heat and give rise to Heat manifestations. For example, when a Cold pathogen attacks the superficial areas of the body, fever and chills often occur. The fever is related to the stagnation of Defensive Qi, while the chills are due to failure of Defensive Qi to produce its warming effects. Three, controlling the opening and closing of the sweat pores. Sweat is derived from Body Fluids and Blood, but its discharge depends on the function of Defensive Qi. When the striae of muscles are tightly closed due to an attack of external pathogens, Defensive Qi will be unable to go outward, so there is fever and absence of sweating. When Defensive Qi is deficient, spontaneous sweating will occur.

Both Nutritive and Defensive Qi are mainly derived from refined food transported by the Spleen and Stomach. Nutritive Qi flows in the vessels while Defensive Qi flows out of the vessels. Coordination of the two maintains a normal sweat discharge and a normal body temperature. If this coordination is destroyed, abnormal sweating or fever with chills will ensue.



Please browse the following contents for further study:


  1. Introduction

  2. Mechnism of Yin Yang Operation

  3. Pathogenic Factors

  4. Concept of Qi

  5. Concept of Blood, Body Fluid and Qi

  6. Mechnism of Chinese Massage

  7. Visceral Symptom

  8. Inner Canon of Yellow Emperor

  9. Acupuncture Treatment Principle

  10. Five Element Theory

  11. Channels and Meridians

  12. Acupuncture Doctors and Works

  13. Origin of Acupuncture