自王叔和脉经而后。宋之崔嘉彦。明之李时珍。其脉诀皆盛行于世。然皆繁琐莫得其要
领。
仲景脉法。有最要一字诀曰缓。仲景云。阳脉浮大而濡。阴脉浮大而濡。阴脉与阳脉同等者
。
此名曰缓。缓则不疾不徐。以周行于营卫之间。无太过。亦无不及。因推及太过之脉。则若
卫
气盛名曰高。营气盛名曰章。高章相搏名曰纲。不及之脉。则若卫气弱名曰 。营气弱名曰
卑。 卑相搏名曰损。此于缓脉外别着此二条。以明有余不足之脉态。然迟与缓亦微有别。
缓则卫气和。迟则营气和。脉缓而迟。刚柔相得。此名曰强。若缓迟相搏。即名曰沉。凡诊
本脉及病脉。总以相得者为平脉。相搏处认病脉。此是仲景当日言下宗旨。至于表里腑脏。
固从浮沉迟数上看。然合之高章卑 。互相体认。则阴阳之间。虚实判焉。故以大浮数动滑
列为阳脉。沉涩弱弦微列为阴脉。由是引伸触类。则若芤若革若牢之属。种种不一其名。俱
从相搏处分别脉状。以审病因。更以呼吸按之。则若代若结若促之类。亦即从此推出。后世
脉诀。皆宗此分门别类。然此中参伍错综之妙。具有彻上彻下彻表彻里工夫。使非从仲景经
文。反复讨论一番。恶能通其精微哉。
五脏六腑死生吉凶之法。独取决于寸口。内经脉法。以左寸属心。右寸属肺。而难经云
。寸口者
脉之大会。手太阴之脉动也。手太阴肺之经也。其独责在肺者何也。盖以左寸属心。心为一
身营
气之主。右寸属肺。肺为一身卫气之主。此位之分寄者也。然营卫之气。全赖谷气以为输布
。谷气入胃以传于肺。五脏六腑。皆以受气。其清者为营。浊者为卫。营行脉中。卫行脉外
。营卫行阳二十五度。行阴二十五度为一周。五十度复会于手太阴。人一呼一吸。皆出于肺
。
以此为呼吸之门。而营卫之主。实两而一者也。仲景于寸口脉。先示以十六字金针。曰浮为
在表。沉为在里。数为在腑。迟为在脏。夫以人身为论。则背为阳。腹为阴。外为阳。内为
阴。腑为阳。脏为阴。以脉象而论。则寸为阳。尺为阴。浮为阳。沉为阴。数为阳。迟为阴
。寸本属阳。而何以并得为藏阴之诊。故仲景复申言之曰。假令脉迟。故知在脏也。由此观
之
。不特阳经之病。宜取决于寸口。即病之由阳入阴。或直入阴经者。寸口之诊。皆不容忽
矣。有此十六字以为大纲。此外之相搏而成病脉者。即从此引伸触类。以审病因之所在。此
在平日熟玩工夫。
自从王叔和的《脉经》问世之后，宋代的崔嘉彦、明代的李时珍，他们的脉诀都在世间广泛流行。然而这些内容都繁琐杂乱，抓不住要领。
仲景（张仲景）的脉法中，有一个最重要的字诀，就是“缓”字。仲景说：阳脉浮大而濡软，阴脉也是浮大而濡软，阴脉与阳脉程度相等，这就叫做“缓”。缓脉就是不快不慢，在营气（营养气血）和卫气（防御气血）之间均匀运行，既不过分亢盛，也不虚弱不足。由此推及到太过盛的脉象，如果卫气盛，就叫做“高”；营气盛，就叫做“章”；高和章相互搏结，就叫做“纲”。至于不及（虚弱）的脉象，如果卫气弱，就叫做“卑”；营气弱，也叫做“卑”；这两个“卑”相互搏结，就叫做“损”。这是在缓脉之外另外列出这两条，来阐明有余和不足两种脉象的状态。然而迟脉和缓脉也有细微的区别：缓脉代表卫气和调，迟脉代表营气和调。脉象既缓又迟，刚柔相济，这就叫做“强”。如果缓脉和迟脉相互搏结，就叫做“沉”。凡是诊察本脉（正常脉）和病脉，总以两者相得（和谐共存）为平脉（正常脉），在两者相搏结的地方辨认出病脉。这是仲景当时言语中的宗旨所在。至于表里、腑脏的判断，固然可以从浮、沉、迟、数脉来看，但如果结合高、章、卑、损等脉象互相体认，那么阴阳之间的虚实就能分辨清楚了。所以将大、浮、数、动、滑列为阳脉，将沉、涩、弱、弦、微列为阴脉。由此引申触类旁通，像芤脉、革脉、牢脉等等，名称各不相同，都是从相搏结的地方分别脉状，从而审察病因。再加上通过呼吸次数来按压诊察，像代脉、结脉、促脉之类，也就从此推导出来。后世的脉诀，都遵循这种分门别类的方法。然而这其中参差错综的奥妙，具有贯通上下、表里的功夫，如果不是从仲景的经文出发，反复讨论一番，怎么能通晓其中的精微之处呢？
五脏六腑的死生吉凶之法，唯独取决于寸口脉。内经脉法认为，左寸归属于心，右寸归属于肺。而《难经》说：“寸口是脉的大会合，是手太阴肺经的搏动处。”手太阴就是肺经。为什么唯独重视肺呢？大概因为左寸属心，心是一身营气的主人；右寸属肺，肺是一身卫气的主人。这是部位的分寄关系。然而营卫之气，完全依赖谷气（水谷精微）来进行输布。谷气进入胃后传送给肺，五脏六腑都从中接受气机。其中清轻的部分成为营气，重浊的部分成为卫气。营气行于脉管之中，卫气行于脉管之外。营卫之气在阳分运行二十五周次，在阴分运行二十五周次，合为一周。五十周次后重新会合于手太阴肺经。人每一次呼气吸气，气都出于肺。肺以此为呼吸的门户，同时也是营卫的主宰，实际上是两个功能统一为一个整体。仲景对于寸口脉，先示人以十六字的金针口诀，说：浮脉主在表，沉脉主在里，数脉主在腑，迟脉主在脏。拿人身来说，背部为阳，腹部为阴；外部为阳，内部为阴；腑为阳，脏为阴。从脉象来说，寸部为阳，尺部为阴；浮脉为阳，沉脉为阴；数脉为阳，迟脉为阴。寸部本来属阳，为什么又能作为诊断脏（阴）病的依据呢？所以仲景再次申述说：假如脉象迟缓，就知道病在脏。由此可见，不仅阳经的病宜由寸口脉来判断，即使是病邪由阳入阴，或者直中阴经的情况，寸口的诊察也都不可忽略。有了这十六字作为大纲，除此之外因相搏结而形成的病脉，就可以从此引申触类旁通，来审察病因所在。这需要平日熟读玩味的功夫。
Since the publication of Wang Shuhe's *Mai Jing* (Pulse Classic), Cui Jiayan of the Song Dynasty and Li Shizhen of the Ming Dynasty had their pulse rhymes widely circulated in the world. However, these works were all cumbersome and failed to grasp the essential points.
Zhongjing’s pulse methodology features a most crucial one-character key: "Huan" (Slow/Relaxed). Zhongjing stated: "The Yang pulse is Floating, Large, and Ru (Soft); the Yin pulse is also Floating, Large, and Ru. When the Yin pulse and Yang pulse are equal in degree, this is called 'Huan'." The Huan pulse is neither too fast nor too slow, circulating evenly between Ying Qi (Nutritive Qi) and Wei Qi (Defensive Qi), having neither excess nor deficiency. Extending from this to pulses of excess: if Wei Qi is excessive, it is called "Gao" (High); if Ying Qi is excessive, it is called "Zhang" (Chapter/Abundant); when Gao and Zhang contend with each other, it is called "Gang" (Cord-like/Taut). Regarding pulses of deficiency: if Wei Qi is weak, it is called "Bei" (Low/Inferior); if Ying Qi is weak, it is also called "Bei"; when these two Bei states contend, it is called "Sun" (Damaged/Depleted). These two categories are listed separately outside the Huan pulse to clarify the states of excess and deficiency. However, Chi (Slow) and Huan have subtle differences: Huan indicates harmonious Wei Qi, while Chi indicates harmonious Ying Qi. A pulse that is both Huan and Chi represents a balance of rigidity and softness, called "Qiang" (Strong). If Huan and Chi contend, it is called "Chen" (Deep). In diagnosing original pulses and pathological pulses, harmony between them constitutes the Ping Pulse (Normal Pulse); pathology is identified where they contend. This was the core principle articulated by Zhongjing. Regarding the differentiation of Exterior/Interior and Fu/Organ, although one generally looks at Floating, Deep, Slow, and Rapid pulses, combining these with Gao, Zhang, Bei, and Sun allows for the discrimination of Deficiency and Excess within Yin and Yang. Therefore, Da (Large), Floating, Rapid, Active, and Slippery are classified as Yang pulses; Chen (Deep), Choppy, Weak, String-taut, and Fine are classified as Yin pulses. By extending this logic, pulses such as Kou (Scallion-stalk), Ge (Leather), and Lao (Firm) vary in name but are distinguished by their contention to ascertain the cause of disease. Furthermore, by counting respiration during palpation, Dai (Intermittent), Jie (Knotted), and Cu (Rapid-intermittent) pulses can be deduced. Later pulse manuals followed this classification system. Yet, the profound intricacy here requires comprehensive understanding from top to bottom and exterior to interior. Without repeatedly discussing Zhongjing’s classic texts, how could one penetrate its subtleties?
The laws governing life, death, auspiciousness, and misfortune of the Five Zang and Six Fu organs depend solely on the Cun Kou (Radial Artery) pulse. Internal pulse theory assigns the Left Cun to the Heart and the Right Cun to the Lung. The *Nan Jing* (Classic of Difficult Issues) states: "The Cun Kou is the great assembly of pulses, the site of movement of the Hand-Taiyin Meridian." The Hand-Taiyin is the Lung Meridian. Why is emphasis placed solely on the Lung? It is because the Left Cun belongs to the Heart, which is the master of the body's Ying Qi; the Right Cun belongs to the Lung, which is the master of the body's Wei Qi. This represents a functional allocation of location. However, Ying and Wei Qi rely entirely on Gu Qi (Grain Essence) for distribution. Gu Qi enters the Stomach and transmits to the Lung, allowing the Five Zang and Six Fu organs to receive Qi. The clear portion becomes Ying Qi, and the turbid portion becomes Wei Qi. Ying Qi circulates within the vessels, while Wei Qi circulates outside the vessels. Ying and Wei Qi travel through the Yang aspects twenty-five times and through the Yin aspects twenty-five times to complete one cycle. After fifty cycles, they reconvene at the Hand-Taiyin. Every exhalation and inhalation originates from the Lung. Thus, the Lung serves as the gate of respiration and the master of Ying and Wei, effectively unifying two functions into one entity.
Regarding the Cun Kou pulse, Zhongjing first provided a sixteen-character golden needle mantra: "Floating indicates Exterior; Deep indicates Interior; Rapid indicates Fu organs; Slow indicates Zang organs." In terms of the human body, the back is Yang, the abdomen is Yin; the exterior is Yang, the interior is Yin; Fu organs are Yang, Zang organs are Yin. In terms of pulse appearance, the Cun position is Yang, the Chi position is Yin; Floating is Yang, Deep is Yin; Rapid is Yang, Slow is Yin. Since the Cun position inherently belongs to Yang, why can it also serve as the diagnostic site for Zang (Yin) diseases? Therefore, Zhongjing reiterated: "If the pulse is Slow, one knows the disease is in the Zang." From this, it is evident that not only should diseases of the Yang meridians be determined by the Cun Kou pulse, but even when pathogens move from Yang to Yin or directly invade the Yin meridians, the diagnosis via Cun Kou must not be neglected. With these sixteen characters as the outline, all other pathological pulses formed by contention can be extended and categorized to ascertain the location of the disease. This requires diligent study and familiarization in daily practice.