Library

In general, among all methods of diagnosing diseases, none is more exquisite than pulse diagnosis (Mai Zhen). However, there are cases where the pulse and symptoms correspond, and cases where they contradict each other; this involves profound principles. Therefore, whenever one encounters ambiguous or difficult-to-distinguish situations, it is essential to employ the Four Diagnostic Methods (Wang, Wen, Wen, Qie - Inspection, Auscultation/Olfaction, Inquiry, Palpation) to inquire in detail about the cause of the disease, while simultaneously observing the voice and complexion. By correcting with reason within the context of the root and branch, and the sequence of events, one can ascertain the truth. If these aspects are not examined, and one merely relies on a single pulse check, treating arbitrarily, how can one know that pulses and symptoms often have true and false manifestations? If one's understanding is not accurate, how can errors be avoided? Moreover, for those who diagnose frequently, understanding is relatively easy; for those diagnosing for the first time, making a judgment is very difficult. This is why the Four Diagnostic Methods cannot be neglected. Thus, the *Nan Jing* (Classic of Difficult Issues) places palpation (Qie) at the end of the four diagnostic methods, implying a deep meaning. Tao Jie'an also stated: "Inquiry reveals the exterior, while pulse observation reveals the interior." It all lies in the two characters "flexible adaptation," which are the key secrets of pulse diagnosis in clinical practice. This theory was explained most extensively by Wang Shishan and is attached to the subsequent volume.

The principles of pulse diagnosis found in various schools include the orderly sequence of the Six Channels (Liu Jing), the defined positions of Zang-Fu Manifestations (Zang Xiang), and the rules of the Three Positions and Nine Probes (San Bu Jiu Hou). These are clear and evident, seemingly detailed and complete. However, when applied in clinical practice, one feels like gazing at the ocean, unable to determine what is the critical point and what is the shore. In my early years, I was often confused by this many times. Now, upon careful examination of the cause, I realize that the problem of losing one's way at a fork in the road lies in failing to grasp the concept of "Uniqueness" (Du). Let us speak briefly of positions: everyone says that the Heart, Liver, and Kidney occupy the three positions (Cun, Guan, Chi) on the left hand, while the Lung, Spleen, and Mingmen (Gate of Life) occupy the three positions on the right hand. Thus, by position, one seeks the Zang-Fu organs; by Zang-Fu organs, one seeks the disease. Everyone believes that no disease can hide. So, examining the Cun position seems to indicate disease in the Heart and Lungs; examining the Guan position seems to indicate disease in the Liver and Spleen; examining the Chi position seems to indicate disease in the two Kidneys. Since there is no position without a pulse, nor a pulse without disease, where exactly is the disease? Who is right and who is wrong? This is hard to say. Further observing the symptoms: for example, headache is just one symptom. The disease originates above, so the response should be in the two Cun positions. But speaking from the perspective of meridians and Zang-Fu, shouldn't Shaoyang and Yangming headaches correspond to the Guan position? Shouldn't Taiyang headaches correspond to the left Chi position? With no distinction between upper and lower, this is hard to clarify. Similarly, strangury and enuresis are just one symptom. The disease originates below, governed by the Chi position. But if Qi fails to secure, the disease is in the right Cun; if Shen (Spirit) fails to consolidate, the disease is in the left Cun. Without distinguishing source and flow, this is hard to clarify. Such examples abound in all diseases. If one insists on explaining by position, the interconnection between upper and lower makes rigid adherence impossible. If one insists on explaining by meridians and Zang-Fu, the shifting of controlling and controlled relationships makes dogmatism impossible. Words cannot fully express meaning, and paintings cannot fully capture spirit; this is universally true. Thus, it can be seen that what various schools list is merely tracing shadows, saying one thing but losing another, capturing only one-tenth of the truth. One only feels that the more there is, the more complex it becomes; the more complex, the more erroneous it becomes; and the deeper the confusion. Therefore, a skilled pulse reader values observing Shen (Spirit/Vitality) over observing Xing (Form/Shape). Observing form yields thousands of shapes, yet misses the essence; observing Shen is singular and refined, uniquely revealing the truth.

The meaning of "Du" (Uniqueness/Particularity) includes Du of Position, Du of Zang-Qi, and Du of Pulse Body. Du of Position means that while other positions are normal, this specific one deviates slightly; the deviation hides the pathology, which constitutes the "Du." Du of Zang-Qi is not constrained by position. For instance, wherever a Hong (Surging) pulse appears, it is the Heart pulse; wherever a Xian (Wiry) pulse appears, it is the Liver pulse; the Lung pulse floats, the Spleen pulse is slow, the Kidney pulse is stone-like. Within the five Zang organs, each has five pulse types. When these five pulses appear mutually, the one that deviates indicates disease. If the deviation is strong, it indicates excess in the respective Zang organ; if weak, it indicates deficiency. This is Du of Zang-Qi. Du of Pulse Body refers to what the classics state: exclusively small is disease, exclusively large is disease, exclusively rapid is disease, exclusively slow is disease, exclusively hot is disease, exclusively cold is disease, exclusively sunken is disease. This is Du of Pulse Body. Summarizing these three, the meaning of "Du" is revealed. Why is it called "Du" if there are three types? It is because these three types of "Du" ultimately return to categories like exclusively small, exclusively large, exclusively rapid, and exclusively slow. Grasping any one of them allows one to see the root of the disease. Hence, the classics say: "Grasp the essence, and you can know life and death." And again: "He who knows the essentials concludes in one word; he who does not know the essentials scatters infinitely." This is precisely what is meant.

Although so, "Du" is not easy to discuss, nor is it difficult. As a virtue, "Du" is the master of all doubts and the source of all phenomena. Its substance is perfectly round, its function is highly flexible. To attain it is like standing atop Mount Tai and looking out: obvious things become obvious, hidden things become hidden, seeming easy yet containing difficulty. It is like recognizing a needle in the vast sea: left becomes left, right becomes right, seeming difficult yet containing ease. However, without eyes that see clearly and a heart that is undivided, one certainly cannot use the "Du" of others to achieve one's own "Du." Thus, it is said that "Du" is not hard to know, but rather that finding someone who truly understands "Du" is hard. One must possess true "Du," lest hypocritical debaters borrow it to justify their biases. True "Du" achieves universal benefit through personal integrity; false "Du" harms oneself through isolation. "Du" and "Du" (poison/harm) sound alike, but their benefits and harms are worlds apart. I mention both to help recognize and prevent this.