The Core of TCM Pulse Diagnosis – You Can Also Derive 27 Types of Pulses
[What is the Core Behind the Pulse?]
There are too many types of pulses in Traditional Chinese Medicine (TCM), and there is a saying that they are numerous yet useless. Therefore, many experienced TCM practitioners summarize them into six words: either floating, sinking, slow, rapid, deficient, or excess. The underlying principle is quite simple because these 27 types of pulses (based on Binhuh Pulse Theory) can be derived using these categories. For example, the Hong Mai (Flooding Pulse) is a floating and large pulse, while the Xi Mai (Thin Pulse) is a sinking, string-like, and weak pulse.
However, even after categorizing the pulses, there remains an unresolved issue regarding the underlying pathogenesis. For instance, the Fu Mai (Hidden Pulse) can indicate stagnation of Qi and blood or deep-seated pathogenic heat; the Chi Mai (Slow Pulse) can indicate cold but may also suggest phlegm, food, or water retention obstructing the blood vessels…
After learning all this, when practitioners feel the pulse in clinical practice, they often find themselves at a loss because their minds are filled with too much knowledge. This is the reason behind the difficulty in understanding the pulse, even if they comprehend the indications of the 27 types of pulses. In clinical practice, the pulse is a composite pulse, so when feeling the pulse, they may be bewildered. How can we avoid such situations?
The author believes that the so-called 27 types of pulses do not encompass all pulse categories. Generally, they can be divided into three levels. The first level is the so-called “pulse categories,” which primarily serve to constitute the basic elements of the pulse—Qi and blood, Yin and Yang, deficiency and excess, cold and heat—and on this basis, elucidate the core essence of the pulse.
The second level includes pulses outside the “pulse categories,” which mainly interpret the different states of the “pulse categories” dynamically under various conditions and serve as a bridge connecting the causes and pathogenesis of diseases.
The third level involves combining these 27 types of pulses to accurately indicate specific pathogenesis, allowing for the formulation of specific treatment principles and methods. Many later scholars do not discuss the first and second levels but rush to write about the third level, which is to forsake the root and pursue the branches. Therefore, this article focuses on analyzing the 27 types of pulses from the first and second levels, primarily emphasizing the pulse categories, aiming to elucidate the core of pulse diagnosis so that those who observe the pulse can understand the principles of pulse diagnosis. Understanding the principles of pulse diagnosis allows one to avoid being confined by the complexities of pulse manifestations.
What is the mechanism behind the pulse? In short, it is the process of change in Qi and blood. The reason blood can circulate in the vessels is due to the propulsion of Qi. Qi can move in the vessels in a regulated manner, neither floating nor sinking, and not chaotic, which is derived from the transport of blood. Therefore, when we observe the pulse, we must first understand the rise and fall of Qi and blood in the human body, the states of deficiency and excess, cold and heat, and their quantities.
As the saying goes, “Observe color and feel the pulse, first distinguish Yin and Yang.” Everything in the world, including the pulse, must be divided into Yin and Yang. Therefore, pulses are also classified as exterior and interior, deficient and excess, cold and heat.
[Deficiency and Excess Categories]
First, let’s discuss deficiency and excess. The method of distinguishing deficiency and excess in the pulse is to press the pulse to the sinking position and observe whether the pulse is strong. If it is strong, it is excess; if it is weak, it is deficiency. This is because TCM believes that sinking indicates the organs, reflecting the essence of the five organs. If the sinking pulse is strong, it indicates sufficient Qi and blood. If a patient’s sinking pulse is strong, it indicates that the pathogenic Qi is strong, and the righteous Qi is not deficient. If it is weak, it indicates that the righteous Qi is deficient. This is the general guideline for judging deficiency and excess in the pulse.
It is important to note that the true Qi of the human body leaking out is similar to a reflection of light, and there is a special pulse that may also be strong while sinking, but this pulse lacks stomach Qi. The “strong” in “sinking and strong” should also be judged based on the person’s age, height, and body type, but the fundamental standard is that if the pulse can still be felt at the bottom of the vessel, it is considered sinking and strong.
[Exterior and Interior Categories]
Next, let’s discuss exterior and interior. Here, it is important to point out that this does not refer to exterior and interior syndromes. Many modern people are less active, stay up late, and use air conditioning. After experiencing an exterior pathogenic factor, many have a sinking pulse, so we cannot simply rely on the pulse to judge exterior or interior syndromes. What we refer to here as exterior and interior pertains to the exterior and interior of Qi and blood.
The mechanism of floating and sinking is simple; it is evident to all. The pulse can float because Yang Qi has sufficient strength to push the pulse upward, indicating a state of Qi and blood moving outward and upward.
Floating can also be divided into deficiency and excess. One type occurs when Qi and blood are deficient; if blood is deficient, Qi has no support, and naturally, it floats. This type of floating is weak when pressed. The other type occurs when the righteous Qi is strong, either due to pathogenic Qi in the exterior resisting the pathogenic factors or internal heat forcing Qi and blood outward. This type of floating is strong when pressed.
Here, the author uses the term “pathogenic Qi” and will use this term many times later. Why use this term? Because the author has found that many people, when learning about the pulse, particularly like to delve into specific pathogenesis, insisting on dissecting this “pathogenic Qi.”
For example, when they see a floating pulse due to an exterior pathogenic factor, they wonder whether it is due to wind or cold. When they see a floating pulse due to internal injury, they question whether it is due to emotional distress causing fire or phlegm and food causing fire, or blood stasis causing fire. In the end, they end up with a plethora of terms: floating and rapid for wind-heat, floating and slow for wind-damp, floating and tight for wind-cold, floating and slippery for phlegm and food forcing Qi and blood outward, floating and string-like for emotional distress causing Qi to rebel and lead to Qi and blood moving outward…
All of these belong to the third level of understanding. When we construct the framework of pulse diagnosis, we must discard all these details and firmly grasp the core, which is Yin and Yang.
The essence of floating pulse is the outward movement of Qi and blood, where deficiency indicates that Qi and blood are deficient, leading to Qi dispersing outward, while excess indicates that pathogenic Qi causes Qi and blood to move outward. This is sufficient; grasping the essence allows us to simplify the complex.
The standard for judging a floating pulse is “strong when lifted, insufficient when pressed.” A normal floating pulse is present in all three positions, and the most vigorous point of the pulse is at the floating position, hence it is called a floating pulse.
Another type of floating pulse is “lightly felt,” referring to a pulse that is floating. Formally, this pulse should only be called “floating pulse” and not “floating pulse.” A floating pulse primarily describes a “fine pulse,” which the ancients described as “like a thin layer of oil on soup,” where pressing it disperses it, and lifting it gathers it, with almost no pulse sensation. The blood in the vessels is just a thin layer, and for such a pulse where both Qi and blood are deficient and cannot be lifted or pressed, the ancients described it as “lightly felt.” Since its essence is also the decline of Qi and blood, it is classified under the floating category.
Later generations misunderstood and gradually misinterpreted that a pulse that can be felt with a light touch is a floating pulse. The author has seen many TCM teachers in clinical practice also tell students that a pulse that can be felt with a light touch is a floating pulse. Zhang Zhongjing said, “Fat people are responsible for floating, thin people are responsible for sinking,” criticizing practitioners for not understanding the differences in body types. Judging floating and sinking solely based on pulse position can lead to significant errors, hence the criticism. Unfortunately, later generations did not heed this warning and misled their students.
Next, let’s discuss the sinking pulse. Similarly, the essence of the sinking pulse is that Yang Qi cannot propel Qi and blood outward. It can also be divided into deficiency and excess. Deficiency indicates that Yang Qi is weak, and this pulse is weak when pressed; excess indicates that pathogenic Qi obstructs, similar to a pressure cooker, where although Yang Qi is sufficient, it still cannot propel Qi and blood outward. This sinking pulse is strong when pressed.
The core of the sinking pulse is that Qi and blood cannot move outward. Deficiency indicates that Yang Qi is weak and cannot propel Qi and blood outward, while excess indicates that there is pathogenic Qi obstructing.
The sinking pulse has a “twin brother,” known as the Fu Mai (Hidden Pulse). In TCM, a pulse that is extremely hidden and requires heavy pressure to the bone to be felt is called a hidden pulse. Its deficiency indicates that Yang Qi has fallen, while its excess indicates that pathogenic factors lead to Qi and blood stagnation. Therefore, the essence of the hidden pulse is the same as that of the sinking pulse, and in terms of classification, it can be grouped with the sinking pulse.
[Cold and Heat Categories]
Next, let’s discuss cold and heat. Generally speaking, a rapid pulse indicates heat, while a slow pulse indicates cold. However, in clinical practice, it is often difficult to find such standard cold and heat pulses. The reason is that modern people’s physical constitution has changed, with long-term inactivity leading to compensatory hypertrophy of the heart, resulting in many rapid pulses. Additionally, long-term consumption of sweet beverages and desserts leads to the accumulation of phlegm-dampness and water retention, resulting in slow pulses. Therefore, we cannot say that a slow or rapid pulse is indicative of cold or heat.
The author believes that there are three golden standards for distinguishing cold and heat from the pulse. First, a rapid pulse that is strong indicates heat without a doubt. Second, a slow pulse that is weak indicates Yang deficiency. Third, a tight pulse indicates cold evil without a doubt, although these are golden standards, they still require comprehensive diagnosis.
A rapid pulse typically has a rate of 90 beats/minute or more, or six beats per breath. This is from a physical perspective. From a spiritual perspective, the pulse rate can also be normal; as long as the pulse feels anxious, it is considered rapid. This is very scientific; just as some people have normal body temperature during menopause but feel hot and cannot tolerate the heat, it is the same principle.
The essence of a rapid pulse is that the speed of Qi and blood circulation has increased, just like water boiling. When the water inside is constantly bubbling, as long as it is hot, it can lead to accelerated Qi and blood circulation. Additionally, it is important to note that Yin deficiency, which functions to moisten and cool, is also a factor. If the Yin in the body is sufficient, even if there is pathogenic heat, a rapid pulse will not appear. Therefore, a rapid pulse that is strong indicates heat evil without a doubt, but we must also consider the aspect of Yin deficiency.
Another situation is the rapid pulse due to deficiency. After running two kilometers, everyone can feel a rapid pulse. The essence of this is that the body’s energy consumption has increased, leading to compensatory acceleration of the heart rate. Similarly, when the righteous Qi is deficient, the heart will increase its strength to circulate blood, resulting in a rapid pulse. This rapid pulse is weak when pressed. Additionally, from a spiritual perspective, if the pulse rate is normal but feels like gasping for breath, it is also a rapid pulse due to deficiency.
The essence of a rapid pulse is that Qi and blood circulation has accelerated; in excess, it indicates heat, while in deficiency, it indicates compensation.
In contrast, the essence of a slow pulse is that Qi and blood circulation is sluggish. Its pulse rate is usually below 60 beats/minute. When the weather is cold, people walk slowly; when the weather is hot, people walk quickly. Cold-blooded animals like turtles and snakes prefer to stay still, while warm-blooded animals like lions and tigers prefer to run. This is the natural order. Therefore, when a person has insufficient Yang Qi and cannot warm the body, their Qi and blood will naturally slow down, hence a slow pulse that is weak when pressed indicates Yang deficiency.
Another situation is when Qi and blood are obstructed by pathogenic factors. This pathogenic factor can be cold or heat. This is similar to thousands of people trying to exit through a small door at the same time; as long as the pathogenic factors obstruct, causing the pulse vessels to narrow, it will lead to a slowdown in Qi and blood circulation. However, at this time, the righteous Qi is not deficient, hence the pulse appears slow but strong when pressed.
[Length and Shortness Categories]
By distinguishing whether the pulse is strong or weak, we can determine deficiency and excess. A floating pulse represents overall Qi and blood moving outward, while a sinking pulse represents overall Qi and blood not moving outward. A rapid pulse that is strong indicates heat, while a slow pulse that is weak indicates cold. This essentially categorizes exterior and interior, deficiency and excess, cold and heat accurately. If floating and sinking are used to judge pulse strength, and rapid and slow are used to judge pulse direction, we can also assist in judging the fullness of Qi and blood from the shape of the pulse, namely the length and shortness of the pulse.
A long pulse physiologically indicates that Qi and blood are abundant, hence “long indicates Qi governance.” Conversely, a pathological long pulse represents an abnormal increase in Qi and blood. In terms of Qi, it is like violently inflating a balloon of normal size; in terms of blood, it is similar to injecting water into beef. Therefore, the essence of a long pulse is the pathological fullness of Qi and blood. For the human body, this indicates Qi rebellion and blood excess. The liver, which regulates Qi dynamics, may be dysfunctional, or pathogenic factors may obstruct, leading to Qi rebellion. Blood excess is mainly due to internal heat causing Qi and blood agitation, similar to boiling water overflowing.
Thus, the essence of a long pulse is the pathological fullness of Qi and blood. The above discussion pertains to excess. Is there deficiency in a long pulse? Certainly. Conversely, a short pulse, which indicates the pathological deficiency of Qi and blood, is the deficiency pulse of a long pulse. Therefore, the essence of a short pulse is that Qi and blood are deficient and cannot propel the blood vessels. Of course, aside from Qi and blood deficiency, pathogenic factors can also lead to a short pulse; the distinction lies in whether it is strong when pressed.
If one can correctly grasp deficiency and excess, floating and sinking, rapid and slow, along with length and shortness, then the core of TCM’s eight principles—Yin and Yang, exterior and interior, deficiency and excess—will be fundamentally understood. The remaining pulses essentially evolve from these eight principles.
[Evolution of Floating Pulse]
First, let’s discuss the evolution of the floating pulse. We already know that the floating pulse represents the outward movement of Qi and blood, where excess indicates that pathogenic Qi is forcing it outward, while deficiency indicates that blood deficiency cannot restrain Yang Qi, leading to outward floating. In clinical practice, there are almost no purely floating pulses because the floating pulse is merely a category pulse; it represents the state of Qi and blood and guides the changes in specific pulse manifestations.
Thus, the excess floating pulse is actually the Hong Mai (Flooding Pulse), while the deficient floating pulse is actually the San Mai (Scattered Pulse). Of course, the Hong Mai and San Mai can also be further divided into Yin and Yang, but this will not be elaborated here.
The Hong Mai can undergo many changes. In the early stages, when the righteous Qi is abundant, Qi and blood are all moving outward, the body may exhibit symptoms of great heat and profuse sweating. Due to excessive sweating, there is a loss of body fluids, leading to a floating, large, and hollow Ke Mai (Hollow Pulse). The hollow aspect indicates the consumption of body fluids, while the floating and large aspect indicates that Qi has no support. The excessive floating in the vessel wall represents that there is an excess of Qi, which is fire, and conversely forces blood to move erratically, leading to further deficiency of blood, which gradually cannot nourish the tendons and vessels, resulting in a pulse that is tense and floating, and pressing it reveals a hollow sensation, known as the Ge Mai (Leather Pulse).
Similarly, the San Mai represents a significant outward floating of Qi and blood. Compared to the Ke Mai, at this time, Qi is even more insufficient, hence it is weak when pressed, forming a floating and soft Ru Mai (Soft Pulse). If Qi and blood continue to be consumed, leading to Qi and blood decline, it will form a pulse that is described as “like a thin layer of oil on soup.”
From the above analysis, it can be seen that the so-called Hong, Ke, Ge, San, and Ru pulses are essentially describing the dynamic changes of the floating pulse through the lens of Yin and Yang. Its essence always revolves around the outward movement of Qi and blood. This is the benefit of grasping the essence; regardless of how the pulse manifestations change, we always remain at the level of Qi and blood Yin and Yang, responding to changes with constancy.
[Evolution of Sinking Pulse]
Next, let’s discuss the evolution of the sinking pulse. Its essence is that Qi and blood cannot move outward, and deficiency and excess are divided into those caused by pathogenic Qi obstruction or those due to Qi and blood deficiency. Therefore, the excess sinking pulse is actually the Lao Mai (Firm Pulse), which is strong and firm when pressed; the deficient sinking pulse is actually the Ruo Mai (Weak Pulse), which is weak and soft when pressed. The sinking pulse also has a similar pulse known as the Fu Mai (Hidden Pulse), where excess indicates that pathogenic Qi obstructs Qi and blood, while deficiency indicates that Qi and blood are extremely deficient and cannot move outward.
Thus, whether it is the Lao Mai or the Ruo Mai, they are merely distinctions of deficiency and excess based on the core foundation of Qi and blood not moving outward.
[Evolution of Rapid Pulse]
Next, let’s discuss the rapid pulse. The essence of the rapid pulse is that Qi and blood circulation has accelerated. At the same time, the rapid excess pulse is also a golden standard for judging heat and Yin deficiency. If the pulse is rapid and strong, it indicates heat excess, where the result may be that Qi and blood cannot harmonize, leading to Yang excess and Yin deficiency, resulting in heat, or heat evil scorching body fluids, leading to phlegm and turbid conditions, resulting in a slippery pulse.
Conversely, a rapid deficient pulse indicates that due to deficiency of righteous Qi, Qi and blood are compensatorily accelerated. If the rapid pulse is weak and cannot replenish Qi and blood, the pulse will not only exhibit rapidity but may also intermittently stop, similar to an elderly person gasping for breath, needing to pause while running, which is a manifestation of deficiency on top of deficiency, known as the Cu Mai (Interrupted Pulse).
[Evolution of Slow Pulse]
Next, let’s discuss the slow pulse. The essence of the slow pulse is that Qi and blood circulation is sluggish, with excess indicating that there is pathogenic Qi obstruction, while the deficient pulse is a golden standard for judging Yang deficiency. In the early stages of pathogenic Qi obstruction, the pulse may not be too slow, leading to a pathological slow pulse. As it progresses, it may become slower, even affecting Qi and blood circulation, resulting in a slow pulse that intermittently stops, known as the Jie Mai (Bound Pulse). If pathogenic Qi disperses widely in the blood vessels, leading to severe obstruction, it will form a Se Mai (Choppy Pulse). However, regardless of the situation, its essence is always that Qi and blood circulation is sluggish.
Additionally, the Jie Mai and Cu Mai, as well as the Hua Mai (Slippery Pulse) and Se Mai, do not have essential differences regarding pathogenic Qi obstruction. As long as there is pathogenic Qi obstruction, these pulse manifestations can occur. To specifically judge the nature of these pathogenic Qi, it is necessary to utilize the third level of pulse understanding, such as a slippery and rapid pulse indicating phlegm-heat, while a fine and choppy pulse indicates blood deficiency and stasis. However, these are not the focus of this article.
[Evolution of Long Pulse]
Finally, let’s discuss the long pulse. According to the Neijing (Inner Canon), the long pulse is described as being like a long rod. The Xian Mai (String-like Pulse) can be seen as a string of a musical instrument, while the Xi Mai (Fine Pulse) can be seen as a strand of hair. Essentially, there is no difference among the three. On one hand, due to Qi rebellion or obstruction by pathogenic Qi, a pathological long pulse may appear. On the other hand, due to the decline of spleen Yang and blood deficiency, the blood vessels gradually constrict, leading to the formation of string-like and fine shapes. Due to the liver’s role in regulating Qi dynamics and storing blood, the long, string-like, and fine pulses also indicate liver and gallbladder diseases.
[Dai Pulse]
Additionally, beyond the eight principles, there is a pulse known as the Dai Mai (Intermittent Pulse), characterized by alternating between being sparse and rapid, moving and stopping, strong and weak, indicating alternating changes in pulse strength, rate, and pauses. Aside from purely appearing as a regular two-beat or three-beat rhythm, the Dai Mai indicates signs of acute illness, pregnancy, or depletion of vital energy.
[Conclusion]
In this era of information explosion, various pulse methods have emerged, including psychological pulse methods for diagnosing psychological diseases, Tai Su pulse methods for assessing wealth, and systematic differentiation pulse methods that can comprehensively and meticulously examine the human body like a CT scan. However, the author firmly believes that although they all involve pulse diagnosis, these methods do not entirely belong to TCM, just as acupuncture guided by foreign neuroanatomy theories does not belong to the TCM theoretical system. The essence of TCM lies in “only understanding Yin and Yang, without collaborating with others.” What we need to do is to understand the abundance and deficiency of Qi and blood in the human body through the four examinations, as well as the rise and fall of righteous Qi and pathogenic Qi. This is the core essence that pulse diagnosis needs to grasp.
Within the vast realm of TCM pulse theory, there are still the three-part nine-indicator pulse methods, full-body pulse methods, seasonal pulse methods, organ pulse methods, and difficult pulse methods, among others. The author has only briefly analyzed the 27 types of pulses from the perspective of Qi and blood in the Binhuh Pulse Theory, which is merely a glimpse into a small part of the whole. The intention is to illustrate that in everything, one must grasp the essence and adhere to a singular principle. The title “Core of Pulse Diagnosis” is merely a gimmick; I do not dare to overestimate myself.