三难曰∶脉有太过，有不及，有阴阳相乘，有覆有溢，有关有格，何谓也？
此言太过不及，皆病脉也。阴乘阳，则阴太过而犯阳，为阳不及；阳乘阴，则阳太过而犯阴，
为阴不及。若相乘之甚者，则为覆溢之脉，而成关格之证也。
然∶关之前者，阳之动也，脉当见九分而浮，过者法曰太过，减者法曰不及。
关前为阳，寸脉所动之位。脉见九分而浮，九，阳数，寸之位浮，阳脉是其常也。过，谓过
于本位，过于常脉；不及，谓不及本位，不及常脉，是皆病脉也。
遂上鱼为溢，为外关内格，此阴乘之脉也。
遂者，径行而直前也。鱼，即鱼际。溢，如水之溢满，而出于外也。阳气太盛，则阴气不得
相营，故曰关。阴气太盛，则阳气不得相营，故曰格。此阴乘阳位，其脉遂溢于鱼际之分，而
成外关内格之证也。
关以后者，阴之动也。脉当见一寸而沉，过者法曰太过，减者法曰不及。
关后为阴，尺脉所动之位。脉见一寸而沉，一寸阴数，尺之位沉，阴脉是其常也。过谓过于
本位，过于常脉；不及谓不及本位，不及常脉，皆病脉也。
遂入尺为覆，为内关外格，此阳乘之脉也。
覆者，如墙之倾覆也。经云∶阳气太盛，则阴气不得相营也。以阴不得营于阳，阳遂下陷而
覆于尺之分，此阳乘阴位之脉，而成内关外格之证也。
故曰覆溢，是其真脏之脉，人不病而死也。
覆溢之脉，乃阴阳离决之征。若覆溢之微，虽关格重证，犹或未至危殆。若覆溢之甚，为真
脏之脉。真脏者，谓脏气已绝。其真形独现于外，不必有疾病，而可决其必死也。
按∶脉乃血中之气，谓之营气，西医言谷食入胃，其精液乃至颈，过肺奉心，化赤为血，应
呼吸，行脉道。即《灵枢·营气篇》云∶营气之道，内谷为宝，谷入于胃。乃传之肺，流溢于
中，布散于外，精专者行于经隧，常营无已，终而复始者是也。盖脏气者，不能自致于手太阴，
必因于胃气，乃至于手太阴，是左右寸口，虽属于肺，而皆有阳明胃气鼓舞其间，故胃为脉之
根，肺为脉之干也。《素问·脉要精微论》云∶阴阳不相应，病名曰关格。六节脏象论以人迎一
盛至四盛以上为格阳，寸口一盛至四盛以上为关阴。而《灵枢》终始、禁服诸篇，亦以人迎四盛，
且大且数，名曰溢阳，溢阳为外格。脉口四盛，且大且数，名曰溢阴，溢阴为内关不通，死不
治。人迎与太阴脉口俱盛四倍以上，命曰关格。关格者，与之短期，此人迎寸口，指结喉两旁
人迎，太渊、经渠间之寸口而言也。越人既独取寸口，不诊十二经动脉，无取乎结喉之人迎。
推溢阳为外格，溢阴为内关之意，知人迎为寸口肺脉之根，寸口为人迎胃脉之干，人迎脉大至
一倍、二倍、三倍、四倍，未有不变见于气口者，以根大而干亦大也。如人迎四倍以上为外格
证，则寸口之脉，亦溢于鱼上为溢阳脉，以应人迎之气。为其根干相通，是寸口以上可察人迎
之气，而结喉两旁之人迎亦不必诊也。此越人独取寸口，以尺寸分覆溢、关格脉证之意也。后之
注《难经》者，不能达越人之意，多主此一脉四名之说，或谓人迎当诊于结喉两旁，死于句下，
泥执经文，皆属误会。不知此节大旨，诊尺寸以详阴阳相乘之候，而察关格之病也。故其设问，
谓古之论脉者。曰太过，曰不及，曰阴阳相乘，曰覆溢，曰关格，若是说来，各有所异否？答
辞始举关之前后，申明阴阳之位，而以过之与减，解太过不及为脉之情势，以上鱼入尺，解覆
溢为脉之现体，而后结其义曰∶是为关格病之所成也。仲景平脉篇云∶寸口脉浮而大，浮为虚，
大为实，在尺为关，在寸为格，关则不得小便，格则呕逆。是据此节而申明其证者也，何注家
不察之甚耶？
第三难说：脉象有太过，有不及，有阴阳相互乘袭，有覆脉、溢脉，有关脉、格脉，这是什么意思呢？
这里所说的太过和不及，都是病态的脉象。阴气乘袭阳气，就是阴气太过而侵犯阳气，导致阳气不及；阳气乘袭阴气，就是阳气太过而侵犯阴气，导致阴气不及。如果这种相乘的情况非常严重，就会形成覆脉和溢脉，进而发展为关格证（一种阴阳离决、上下不通的危重病症）。
然而，关部之前的部位，是阳气运行的地方，脉象应当显现为九分长且浮取可得。超过这个标准的称为“太过”，不足这个标准的称为“不及”。
关前属于阳位，是寸脉搏动的位置。脉象显现为九分长且浮，九是阳数，寸部位置脉象浮起，这是阳脉的正常表现。“过”，是指超过了本来的位置，超过了正常的脉象；“不及”，是指达不到本来的位置，达不到正常的脉象，这些都属于病脉。
脉气直上到达手掌大鱼际部位，称为“溢”，表现为外边闭塞、里边格拒，这是阴气乘袭阳位的脉象。
“遂”的意思是径直向前运行。“鱼”即指大鱼际。“溢”就像水满溢出一样，流出于外部。阳气太盛，阴气就不能与之相互营卫调和，所以称为“关”；阴气太盛，阳气就不能与之相互营卫调和，所以称为“格”。这是阴气乘袭阳位，脉气于是溢出到大鱼际的部位，从而形成外关内格的证候。
关部之后的部位，是阴气运行的地方。脉象应当显现为一寸长且沉取可得。超过这个标准的称为“太过”，不足这个标准的称为“不及”。
关后属于阴位，是尺脉搏动的位置。脉象显现为一寸长且沉，一寸属阴数，尺部位置脉象下沉，这是阴脉的正常表现。“过”是指超过了本来的位置，超过了正常的脉象；“不及”是指达不到本来的位置，达不到正常的脉象，这些都属病脉。
脉气深入尺部以下，称为“覆”，表现为里边闭塞、外边格拒，这是阳气乘袭阴位的脉象。
“覆”的意思，就像墙壁倾倒覆盖一样。医经中说：阳气太盛，阴气就不能与之相互营卫调和。因为阴气不能营卫于阳气，阳气于是下陷并覆盖在尺部的区域，这是阳气乘袭阴位的脉象，从而形成内关外格的证候。
所以说，覆脉和溢脉，是真脏脉（脏腑真气败露的脉象），即使人没有明显的疾病表现，也会死亡。
覆脉和溢脉，是阴阳分离决裂的征象。如果覆脉和溢脉的程度轻微，虽然属于关格的重症，或许还未到危险的地步。如果覆脉和溢脉非常严重，就是真脏脉。所谓真脏，是指脏气已经断绝。其真实的脏气形态独自显露于外，不一定非要有疾病症状，就可以断定其必然死亡。
按语：脉是血中的气，称为营气。西医认为食物进入胃中，其精微物质上升到颈部，经过肺脏奉输于心，化为红色的血液，随着呼吸的节奏，在脉道中运行。这正如《灵枢·营气篇》所说：“营气的运行之道，以内含谷物精华为宝，谷物进入胃中，然后传送给肺，流溢于体内，布散于体外，其中精纯专一的部分运行于经脉隧道之中，常年营运不止，循环往复。”大概脏气本身不能自行到达手太阴肺经的寸口部位，必须依赖胃气的推动，才能到达手太阴肺经。因此，左右寸口虽然归属于肺，但都有阳明胃气在其中鼓舞推动，所以说胃是脉的根本，肺是脉的主干。《素问·脉要精微论》说：阴阳不相呼应，病名叫做关格。《素问·六节脏象论》以人迎脉（颈动脉）比寸口脉大一倍至四倍以上为格阳，寸口脉比人迎脉大一倍至四倍以上为关阴。而《灵枢》的终始、禁服等篇章，也以人迎脉大四倍，而且盛大且数，命名为溢阳，溢阳即为外格。脉口（寸口脉）大四倍，而且盛大且数，命名为溢阴，溢阴即为内关不通，死不治。人迎脉和太阴脉口（寸口脉）都盛大四倍以上，命名为关格。关格者，给予短促的寿命期限。这里的人迎和寸口，指的是结喉两旁的人迎穴处脉搏，以及太渊、经渠之间的寸口脉搏。扁鹊（越人）既然单独选取寸口诊脉，不诊察十二经的动脉，就不需要诊察结喉旁的人迎脉了。推究将溢阳解释为外格、溢阴解释为内关的本意，可知人迎是寸口肺脉的根本，寸口是人迎胃脉的主干。人迎脉大到一倍、两倍、三倍、四倍，没有不在气口（寸口）上显现出来的，因为根本大了，主干自然也大。如果人迎脉大四倍以上成为外格证，那么寸口的脉象，也会溢出到大鱼际以上成为溢阳脉，以对应人迎脉的气机。因为根与主干相通，所以在寸口以上就可以察知人迎脉的气机，而不必诊察结喉两旁的人迎脉了。这就是扁鹊单独取寸口，用尺寸分部来分辨覆脉、溢脉及关格脉证的原因。后世注解《难经》的人，不能通达扁鹊的本意，大多主张这一脉具有四种名称的说法，或者认为人迎应当在结喉两旁诊察，死于拘泥句读之下，执着于经文，都属于误解。不知道这一节的宗旨，是通过诊察尺寸脉来详细观察阴阳相乘的征候，从而察知关格的疾病。所以他设问，说是古代论述脉象的人，提到太过、不及、阴阳相乘、覆溢、关格，像这样说来，它们各自是否有区别呢？回答的话才开始列举关前和关后，申明阴阳的位置，并用“过”与“减”来解释太过和不及是脉的形势，用“上鱼”和“入尺”来解释覆和溢是脉的表现形态，最后总结其含义说：这就是关格病形成的原因。张仲景《平脉篇》说：寸口脉浮而大，浮表示虚，大表示实，在尺部出现叫关，在寸部出现叫格，关则小便不通，格则呕吐逆气。这是根据本节内容来申述其证候的，为什么注家们考察得如此不仔细呢？
Chapter 3 states: There are pulse conditions of excess (Tai Guo), deficiency (Bu Ji), mutual overcoming between Yin and Yang, Fu (inverted) pulses, Yi (overflowing) pulses, Guan (closed) and Ge (blocking) patterns. What does this mean?
The excess and deficiency mentioned here refer to pathological pulses. When Yin overcomes Yang, it means Yin is in excess and invades Yang, resulting in Yang deficiency; when Yang overcomes Yin, it means Yang is in excess and invades Yin, resulting in Yin deficiency. If the mutual overcoming is severe, it forms Fu and Yi pulses, leading to the Guan-Ge syndrome (a critical condition characterized by the separation of Yin and Yang and obstruction of upper and lower communication).
However, the area anterior to the Guan (barrier) position is where Yang moves; the pulse should appear at a length of nine fen and be superficial (Fu). Exceeding this standard is termed "excess" (Tai Guo), while falling short is termed "deficiency" (Bu Ji).
Anterior to the Guan belongs to Yang, which is the location of the Cun (inch) pulse. A pulse appearing at nine fen and superficial is normal for a Yang pulse, as nine is a Yang number and the Cun position naturally presents with a superficial quality. "Excess" refers to exceeding the original position or normal pulse characteristics; "deficiency" refers to failing to reach the original position or normal pulse characteristics. Both are pathological pulses.
If the pulse extends straight up to the thenar eminence (Yu Ji), it is called "Yi" (Overflowing). This manifests as external closure and internal blocking, representing a pulse of Yin overcoming Yang.
"Sui" means moving directly forward. "Yu" refers to the thenar eminence. "Yi" implies overflowing like water spilling out. When Yang Qi is excessively strong, Yin Qi cannot interact harmoniously with it, hence termed "Guan" (Closed); when Yin Qi is excessively strong, Yang Qi cannot interact harmoniously with it, hence termed "Ge" (Blocking). This occurs when Yin overcomes the Yang position, causing the pulse to overflow into the thenar region, forming the external Guan and internal Ge pattern.
The area posterior to the Guan is where Yin moves; the pulse should appear at a length of one cun and be deep (Chen). Exceeding this standard is termed "excess" (Tai Guo), while falling short is termed "deficiency" (Bu Ji).
Posterior to the Guan belongs to Yin, which is the location of the Chi (cubit) pulse. A pulse appearing at one cun and deep is normal for a Yin pulse, as one cun corresponds to Yin numbers and the Chi position naturally presents with a deep quality. "Excess" refers to exceeding the original position or normal pulse characteristics; "deficiency" refers to failing to reach the original position or normal pulse characteristics. Both are pathological pulses.
If the pulse sinks deeply into the Chi region, it is called "Fu" (Inverted/Overturned). This manifests as internal closure and external blocking, representing a pulse of Yang overcoming Yin.
"Fu" implies overturning like a collapsing wall. The classics state: When Yang Qi is excessively strong, Yin Qi cannot interact harmoniously with it. Because Yin cannot nourish Yang, Yang sinks and covers the Chi region. This is a pulse of Yang overcoming Yin, forming the internal Guan and external Ge pattern.
Therefore, it is said that Fu and Yi pulses are Zang-Zang pulses (pulses revealing the true state of organ qi). Even if the patient shows no obvious disease symptoms, death will occur.
Fu and Yi pulses are signs of the separation and rupture of Yin and Yang. If the Fu and Yi manifestations are mild, although they represent severe Guan-Ge syndromes, they may not yet be critical. However, if Fu and Yi manifestations are severe, they constitute Zang-Zang pulses. "Zang-Zang" means the organ qi has been exhausted. The true form of the organ qi appears independently on the surface; regardless of whether there are specific disease symptoms, certain death can be predicted.
Commentary: The pulse is the Qi within the blood, also known as Ying Qi (Nutritive Qi). Western medicine posits that after food enters the stomach, its essence rises to the neck, passes through the lungs to the heart, transforms into red blood, and circulates in the vessels according to respiration. This aligns with the *Ling Shu · Ying Qi Chapter*: "The path of Ying Qi treasures the grain entering the stomach. It transmits to the lungs, flows internally, spreads externally, and its purest part travels through the meridians, circulating endlessly." Generally, organ qi cannot reach the Hand-Taiyin Lung meridian's Cun Kou point on its own; it must rely on the driving force of Wei Qi (Stomach Qi) to arrive there. Thus, although the left and right Cun Kou points belong to the Lung, they are energized by the Yangming Stomach Qi. Therefore, the Stomach is the root of the pulse, and the Lung is the trunk. The *Su Wen · Mai Yao Jing Wei Lun* states: "When Yin and Yang do not correspond, the disease is named Guan-Ge." The *Su Wen · Liu Jie Zang Xiang Lun* describes Ge-Yang (Blocking-Yang) when the Ren Ying pulse (carotid) is one to four times larger than the Cun Kou pulse, and Guan-Yin (Closing-Yin) when the Cun Kou pulse is one to four times larger than the Ren Ying pulse. Similarly, chapters in the *Ling Shu* such as *Zhong Shi* and *Jin Fu* name a Ren Ying pulse four times larger, vigorous and rapid, as "Yi-Yang" (Overflowing-Yang), which constitutes external Ge. A Pulse Kou (Cun Kou) pulse four times larger, vigorous and rapid, is named "Yi-Yin" (Overflowing-Yin), constituting internal Guan blockage, which is untreatable and fatal. When both Ren Ying and Taiyin Pulse Kou (Cun Kou) are more than four times larger, it is named Guan-Ge. Guan-Ge indicates a short life expectancy. Here, "Ren Ying" refers to the pulse beside the larynx, and "Cun Kou" refers to the pulse between Tai Yuan and Jing Qu. Since Yue Ren (Bian Que) exclusively took the Cun Kou pulse and did not examine the twelve meridian arteries, there was no need to examine the Ren Ying at the larynx. Inferring the meaning of naming Yi-Yang as external Ge and Yi-Yin as internal Guan, we understand that Ren Ying is the root of the Cun Kou Lung pulse, and Cun Kou is the trunk of the Ren Ying Stomach pulse. If the Ren Ying pulse is one, two, three, or four times larger, it invariably manifests at the Qi Kou (Cun Kou), because if the root is large, the trunk is also large. If the Ren Ying pulse exceeds four times, indicating an external Ge syndrome, the Cun Kou pulse will also overflow above the thenar eminence as an Yi-Yang pulse, corresponding to the Qi of the Ren Ying. Since the root and trunk are connected, the Qi of the Ren Ying can be observed from the Cun Kou upwards, making examination of the Ren Ying beside the larynx unnecessary. This explains why Yue Ren exclusively used the Cun Kou to differentiate Fu/Yi and Guan/Ge pulse patterns using the Cun and Chi positions. Later commentators on the *Nan Jing* failed to grasp Yue Ren's intent, often adhering to the theory that one pulse has four names, or insisting that Ren Ying must be examined at the larynx, dying due to rigid adherence to textual phrasing. These are misunderstandings. They fail to realize that the main purport of this section is to diagnose the patterns of Yin-Yang mutual overcoming by examining the Cun and Chi pulses to identify Guan-Ge diseases. His question asks: Ancient pulse theorists spoke of excess, deficiency, Yin-Yang mutual overcoming, Fu/Yi, and Guan/Ge; do these terms differ? The answer begins by listing anterior and posterior to the Guan to clarify Yin-Yang positions, explaining excess and deficiency as pulse dynamics via "overstepping" and "falling short," and explaining Fu and Yi as pulse morphology via "ascending to the thenar" and "descending into the Chi." It concludes that these constitute the formation of Guan-Ge disease. Zhang Zhongjing’s *Ping Mai Pian* states: "A Cun Kou pulse that is floating and large: floating indicates deficiency, large indicates excess. At the Chi position, it is Guan; at the Cun position, it is Ge. Guan results in inability to urinate; Ge results in vomiting and reflux." This elaborates on the syndromes based on this section. Why were commentators so negligent in observing this?