一岁阴阳升降。会于立春。一日阴阳晓昏。会于艮时。一身荣卫还周。会于手太阴。同天度一万三千五百息。荣卫
始于从中焦。（按于从二字。当衍其一。）注手太阴阳明。阳明注足阳明太阴。太阴注手少阴太阳。太阳注足太阳少阴。
少阴注手心主少阳。少阳注足少阳厥阴。厥阴复还注手太阴。天度二十四气。昼夜二十四时。人身经二十四条。（按原本
此下复有人身经二十四条七字。系衍文。今删。）流注与天同度。所以计一万三千五百息。
\r漏水下百刻图\pt40a1.bmp\r
水下四刻移一经复还于手太阴其得百刻荣卫各计二十五度。
二难曰。脉有尺寸。何谓也。然。尺寸者、脉之大要会也。
吕曰。诸十二经脉。三部九候。有病者皆见于尺寸。故言脉之大要会也。丁曰。旧经注此说为五脏六腑之法者非也。
大要会者、谓尺寸阴阳往复。各有要会也。
从关至尺是尺。内阴之所治也。从关至鱼际是寸。内阳之所治也。
吕曰。至尺者、言从尺至关。其脉见一寸。而言尺者、是其根本。寸口长一寸。而脉见九分。阳数奇。阴数偶也。
故分寸为尺。分尺为寸。
丁曰。分寸为尺者、人从关至尺泽穴当一尺也。于其尺内。分一寸以代一尺之法。是故分寸为尺分尺为寸也。
故阴得尺内一寸。
丁曰。阴数偶也。
阳得寸内九分。
丁曰。阳数奇也。
尺寸终始一寸九分。故曰尺寸也。
丁曰。尺寸之法。旧经有注。言诸家所传撰不同。执引三寸。（按以下注考之。此寸字当作部。）辄相去一寸。以备
三寸。并不见一寸九分之理。其一寸九分之法者。盖为尺寸之位。各有阴阳始终也。阳气者、生于尺而动于寸。阴气者、
生于寸而动于尺。是以法阳气。始生于立春。上至芒种之节。其数九。三阳王于前法寸内九分而浮。夏至之节。其气下
行。至立冬而终。其数十。即三阴王于后法尺内一寸而沉。故知尺寸各有始终也。此是越人引其阳中阴阳始终也。所谓
阴中阴阳始终者。阴气复从立秋而生。下至冬至之节。其数十。冬至之后。随少阳上行。至立夏之节。其数九。此者天
地阴阳始终。故法尺寸阴阳各有始终也。天地要会之门。在于四立。谓之天门、地户、人门、鬼门。人之气口人迎左右
神门。亦法也。杨曰。寸关尺三位。诸家所撰。多不能同。故备而论之。以显其正。按皇甫士安脉诀。以掌后三指为三
部。一指之下为六分。三部凡一寸八分。华佗脉诀云。寸尺位各八分。关位三分。合一寸九分。王叔和脉诀云。三部之
位。辄相去一寸。合为三寸。诸经如此差异。则后之学人。疑惑弥深。然脉法始于黄帝。难经起自扁鹊。此之二部俱祖
宗。诸家诸论盖并枝叶尔。正可务本遗末。不容逐末忘本。今的举指归。用明大要。宜根据黄帝正经。以掌后三寸为三部。
则寸与关尺。各得一寸。备三才之义也。此法永定。不可移改。其王叔和、可谓得之矣。凡诊脉者、先明三部九候之本
位。五脏六腑之所出。然后可以察其善恶。以别浮沉。如其本位尚迷。则病源莫辨。欲其愈疾。亦难矣哉。三部者。寸
关尺也。九候者、天地人也。一部之中。则有天地人。三部之中。合为九候。以候五脏之气也。其五脏六腑所出者。左
手寸口者。心与小肠脉之所出也。关上者。肝与胆脉之所出也。尺中者。肾与膀胱脉之所出也。关前一分者。人迎之位
也。关后一分。神门之位也。右手寸口者。肺与大肠脉之所出也。关上者。脾与胃脉之所出也。尺中者。命门三焦脉之
所出也。关前一分者。气口之位也。关后一分者。神门之位也。凡五脏之脉并为阴。阴脉皆沉。六腑之脉并为阳。阳脉
皆浮。假令左手寸口脉浮者。小肠脉也。沉者。心之脉也。余皆仿此。斯乃脉位之纲维。诊候之法式也。虞曰。杨氏诸
论数家寸尺长短部分。互有不同。令后人难为根据。庶今明之。以示后学。华佗之说。乃如脉经言。果不谬矣。王叔和
以三寸为式。义有隐微。此乃黄帝正经之说。岂有误也。况上古以一肤指为四寸。王叔和必取其肤指之三寸。与今之一
寸九分。短长相近也。何休注公羊传云。侧手为肤。按指为寸。即其义也。况越人生于周。采灵枢素问作此难经。今之
寸尺度量。乃周之制也。故越人取一寸九分为定式。乃天九地十之义也。
一岁的阴阳升降，交汇于立春时节。一天的阴阳晨昏变化，交汇于艮时（凌晨1-3点）。人体营卫之气循环周身，交汇于手太阴肺经。其周期与天度相应，共计一万三千五百息。营卫之气起始于中焦。（按语：原文“于从”二字，应当衍出一个字。）注入手太阴、手阳明经；手阳明经注入足阳明、足太阴经；足太阴经注入手少阴、手太阳经；手太阳经注入足太阳、足少阴经；足少阴经注入手厥阴心包经、手少阳经；手少阳经注入足少阳、足厥阴经；足厥阴经又复还注入手太阴肺经。天度有二十四节气，昼夜有二十四个时辰，人身有二十四条经脉。（按语：原本在此处重复出现“人身经二十四条”七字，系衍文，现已删除。）气血流注与天度相同，所以计算为一万三千五百息。
[图片：漏水下百刻图]
水下四刻，气血移换一条经脉，最终复还于手太阴肺经。这样一百刻的时间，营气和卫气各运行二十五周。
第二难问：脉象有寸和尺，这是什么意思呢？回答说：寸和尺，是脉诊的大要汇聚之处。
吕氏说：十二经脉的三部九候，有病者都会在寸口脉上显现出来，所以说它是脉之大要会。
丁氏说：旧经注释将此解释为五脏六腑之法是不对的。所谓大要会，是指寸和尺的阴阳往复，各有其关键的汇聚点。
从关部到尺部，称为尺，这是阴气所治理的部位。从关部到鱼际，称为寸，这是阳气所治理的部位。
吕氏说：说到尺，是指从尺部至关部的距离，其脉可见一寸长。之所以称为尺，是因为它是根本。寸口脉长一寸，但脉动可见九分。阳数为奇数，阴数为偶数。因此将寸分为尺，将尺分为寸。
丁氏说：所谓将寸分为尺，是指人从关部到尺泽穴的距离大约是一尺。在尺的内部，取一寸来代替一尺的方法。所以是将寸分为尺，将尺分为寸。
因此，阴气占据尺内的一寸。
丁氏说：阴数是偶数。
阳气占据寸内的九分。
丁氏说：阳数是奇数。
寸和尺从头到尾共长一寸九分，所以称为尺寸。
丁氏说：尺寸的方法，旧经中有注释，说各家所传撰的不同，有的主张三寸。（根据以下注文考证，这里的“寸”字应当作“部”。）彼此相差一寸，用来凑成三寸，却都不见一寸九分的道理。那一寸九分的方法，大概是认为寸和尺的位置，各有阴阳的始终。阳气，生于尺部而作用于寸部；阴气，生于寸部而作用于尺部。因此效法阳气，开始生于立春，上至芒种节气，其数为九。三阳王于前，效法寸内九分而浮起；夏至节气，其气下行，至立冬结束，其数为十。即三阴王于后，效法尺内一寸而沉伏。所以知道寸和尺各有始终。这是越人引用其中的阳中之阴阳始终的道理。所谓阴中之阴阳始终，阴气又从立秋而生，下至冬至节气，其数为十。冬至之后，随少阳之气上行，至立夏节气，其数为九。这是天地阴阳的始终，所以效法尺寸阴阳各有始终。天地交汇的关键门户，在于四立（立春、立夏、立秋、立冬），称为天门、地户、人门、鬼门。人的气口和人迎，左右的神门，也是效法于此。
杨氏说：寸、关、尺三个部位，各家所撰写的，大多不能相同，所以全面论述它们，以显示正确的观点。按皇甫士安的《脉诀》，以手掌后的三指为三部，一指之下为六分，三部总共一寸八分。华佗的《脉诀》说：寸位和尺位各八分，关位三分，合起来一寸九分。王叔和的《脉诀》说：三部的位置，彼此相差一寸，合为三寸。诸经如此差异，那么后世的学人，疑惑更加深重。然而脉法始于黄帝，《难经》起自扁鹊，这两部都是祖宗经典，诸家的各种论述不过是枝叶罢了。正应该务求根本而舍弃末节，不容许追逐末节而忘记根本。现在明确列举指归，用以阐明大要，应当依据黄帝的正经，以手掌后三寸为三部，那么寸、关、尺各得一寸，具备天、地、人三才的意义。此法永远固定，不可更改。至于王叔和，可以说是得之了。凡是诊脉的人，先要明确三部九候的本位，以及五脏六腑之所出，然后才可以察知病情的善恶，辨别浮沉。如果对本位尚且迷惑，那么病源就无法分辨，想要治愈疾病，也很难啊。三部，就是寸、关、尺。九候，就是天、地、人。一部之中，包含天、地、人。三部之中，合为九候，用以候察五脏之气。那些五脏六腑所出的部位：左手寸口，是心和小肠脉所出的部位；关上，是肝和胆脉所出的部位；尺中，是肾和膀胱脉所出的部位。关前一分，是人迎的位置；关后一分，是神门的位置。右手寸口，是肺和大肠脉所出的部位；关上，是脾和胃脉所出的部位；尺中，是命门和三焦脉所出的部位。关前一分，是气口的位置；关后一分，是神门的位置。凡是五脏的脉都属阴，阴脉皆沉；六腑的脉都属阳，阳脉皆浮。假如左手寸口脉浮，是小肠脉；沉，是心的脉。其余都仿照这个例子。这是脉位的纲维，诊候的法式。
虞氏说：杨氏等人的论述中，各家对寸、尺长短部分的划分，互有不同，令后人难以依据，希望今天能阐明它，以展示给后学。华佗的说法，正如《脉经》所言，果然没有错误。王叔和以三寸为法式，义理中有隐微之处，这乃是黄帝正经的说法，难道会有误吗？况且上古时期以一个手指宽度（一夫）为四寸，王叔和必定取其手指宽度的三寸，与现在的一寸九分，长短相近。何休注解《公羊传》说：侧着手掌为肤，按着手指为寸，就是这个意思。况且越人（扁鹊）生于周代，采集《灵枢》、《素问》的内容作成这部《难经》，现在的寸尺度量，乃是周代的制度。所以越人取一寸九分作为定式，乃是天九地十的意义。
The rising and falling of Yin and Yang over a year converge at the Beginning of Spring (Lichun). The morning and dusk changes of Yin and Yang within a day converge at the Gen hour (1:00-3:00 AM). The circulation of Ying (Nutrient Qi) and Wei (Defensive Qi) throughout the body converges at the Hand-Taiyin Lung Meridian. This cycle corresponds to the celestial degrees, totaling 13,500 breaths (Xi). Ying and Wei Qi originate from the Middle Jiao (Middle Burner). [Note: The characters "Yu Cong" in the original text likely contain a duplication error.] They flow into the Hand-Taiyin and Hand-Yangming meridians; Hand-Yangming flows into Foot-Yangming and Foot-Taiyin; Foot-Taiyin flows into Hand-Shaoyin and Hand-Taiyang; Hand-Taiyang flows into Foot-Taiyang and Foot-Shaoyin; Foot-Shaoyin flows into Hand-Jueyin Pericardium and Hand-Shaoyang; Hand-Shaoyang flows into Foot-Shaoyang and Foot-Jueyin; Foot-Jueyin then returns to flow into the Hand-Taiyin Lung Meridian. There are twenty-four solar terms in the celestial cycle, twenty-four hours in a day and night, and twenty-four meridians in the human body. [Note: The phrase "Human body has twenty-four meridians" appearing again here is considered a textual duplication and has been deleted.] The flow of Qi and Blood follows the same pattern as the celestial cycle, hence calculated as 13,500 breaths.
[Image: Diagram of Water Dropping One Hundred Marks]
When the water clock drops four marks, the Qi shifts through one meridian and finally returns to the Hand-Taiyin Lung Meridian. In this period of one hundred marks, Ying and Wei Qi each circulate twenty-five cycles.
Difficulty 2 asks: What is meant by the Cun (Inch) and Chi (Cubit) positions in pulse diagnosis? The answer is: Cun and Chi are the major convergence points of pulse diagnosis.
Mr. Lv states: The Three Positions and Nine Palpations of the twelve primary meridians manifest their pathologies at the Cun Kou (Radial Artery). Therefore, it is called the major convergence of pulses.
Mr. Ding states: The old commentary interpreting this as the method for the Five Zang and Six Fu organs is incorrect. The term "major convergence" refers to the reciprocal movement of Yin and Yang in Cun and Chi, each having its key convergence point.
From the Guan (Bar) position to the Chi position is called Chi, which governs Yin. From the Guan position to the Yu Ji (LU10) acupoint is called Cun, which governs Yang.
Mr. Lv states: When referring to Chi, it denotes the distance from the Chi position to the Guan position, where the pulse is visible for one Cun length. It is called Chi because it is the root. The Cun Kou pulse is one Cun long, but the palpable pulse movement is nine Fen. Yang numbers are odd, and Yin numbers are even. Thus, Cun is divided into Chi, and Chi is divided into Cun.
Mr. Ding states: Dividing Cun into Chi refers to the fact that the distance from the Guan position to the Chi Ze (LI11) acupoint is approximately one Chi. Within the Chi region, one takes one Cun to represent the method of one Chi. Hence, Cun is divided into Chi, and Chi is divided into Cun.
Therefore, Yin occupies one Cun inside the Chi position.
Mr. Ding states: Yin numbers are even.
Yang occupies nine Fen inside the Cun position.
Mr. Ding states: Yang numbers are odd.
The total length of Cun and Chi from start to finish is one Cun and nine Fen, hence the name Cun-Chi.
Mr. Ding states: Regarding the method of Cun-Chi, old commentaries note that various schools differ. Some advocate three Cun. [Based on subsequent notes, the character "Cun" here should likely be "Bu" (Position/Section).] They differ by one Cun to make up three Cun, yet none explain the rationale for one Cun and nine Fen. The method of one Cun and nine Fen assumes that the positions of Cun and Chi each have their own Yin and Yang beginnings and endings. Yang Qi originates in Chi and acts in Cun; Yin Qi originates in Cun and acts in Chi. Therefore, modeling after Yang Qi: it begins to generate at the Beginning of Spring and reaches the Grain in Ear (Mangzhong) solar term, with a number of nine. The Three Yangs dominate anteriorly, modeled after the nine Fen in Cun floating superficially. At the Summer Solstice, the Qi moves downward, ending at the Beginning of Winter, with a number of ten. The Three Yins dominate posteriorly, modeled after one Cun in Chi sinking deeply. Thus, we know Cun and Chi each have their beginnings and endings. This is the Yue Ren (Bian Que) citing the beginning and ending of Yin within Yang. As for the beginning and ending of Yang within Yin: Yin Qi generates again at the Beginning of Autumn and goes down to the Winter Solstice, with a number of ten. After the Winter Solstice, following the Shaoyang Qi, it moves upward to the Beginning of Summer, with a number of nine. These are the beginnings and endings of Heaven and Earth's Yin and Yang, thus modeling the Yin and Yang beginnings and endings of Cun and Chi. The gate of convergence between Heaven and Earth lies in the Four Beginnings (Li Chun, Li Xia, Li Qiu, Li Dong), called the Gate of Heaven, Door of Earth, Gate of Man, and Gate of Ghost. The Ren Ying and Qi Kou of humans, and the Shen Men on left and right, also follow this model.
Mr. Yang states: The positions of Cun, Guan, and Chi vary among different authors. Therefore, I discuss them comprehensively to reveal the correct view. According to Huangfu Mi's Pulse Classic, the three fingers behind the palm constitute three positions, with six Fen under each finger, totaling one Cun and eight Fen. Hua Tuo's Pulse Classic states: Cun and Chi positions are each eight Fen, Guan position is three Fen, totaling one Cun and nine Fen. Wang Shuhe's Pulse Classic states: The three positions differ by one Cun each, totaling three Cun. Such discrepancies in the classics cause deep confusion for later students. However, pulse methods originated from the Yellow Emperor, and the Nan Jing originated from Bian Que. These two works are the ancestors; all other theories are merely branches. One should focus on the root and discard the branches, not chase the branches while forgetting the root. Now, clearly stating the guidelines to illuminate the essentials, one should follow the Yellow Emperor's orthodox texts, taking three Cun behind the palm as the three positions, so that Cun, Guan, and Chi each obtain one Cun, embodying the meaning of Heaven, Earth, and Man. This method is fixed and unchangeable. Wang Shuhe can be said to have grasped it correctly. In all pulse diagnoses, one must first understand the fundamental positions of the Three Positions and Nine Palpations, and the origins of the Five Zang and Six Fu organs, before one can discern good and evil conditions and distinguish floating and sinking qualities. If the fundamental positions are unclear, the source of disease cannot be identified, and curing the illness will be difficult. The Three Positions are Cun, Guan, and Chi. The Nine Palpations are Heaven, Earth, and Man. Within one position, there are Heaven, Earth, and Man. Across three positions, they combine into Nine Palpations to observe the Qi of the Five Zang organs. Regarding the origins of the Five Zang and Six Fu organs: The Cun Kou of the left hand is the origin of the Heart and Small Intestine pulses; the Guan is the origin of the Liver and Gallbladder pulses; the Chi is the origin of the Kidney and Bladder pulses. One Fen anterior to the Guan is the position of Ren Ying; one Fen posterior to the Guan is the position of Shen Men. The Cun Kou of the right hand is the origin of the Lung and Large Intestine pulses; the Guan is the origin of the Spleen and Stomach pulses; the Chi is the origin of the Mingmen (Gate of Life) and Sanjiao (Triple Burner) pulses. One Fen anterior to the Guan is the position of Qi Kou; one Fen posterior to the Guan is the position of Shen Men. All pulses of the Five Zang are Yin, and Yin pulses are all sinking. All pulses of the Six Fu are Yang, and Yang pulses are all floating. For example, if the Cun Kou pulse of the left hand is floating, it indicates the Small Intestine pulse; if sinking, it indicates the Heart pulse. The rest follow this pattern. This is the framework of pulse positions and the standard for diagnosis.
Mr. Yu states: Mr. Yang and others have discussed varying lengths and divisions for Cun and Chi, making it difficult for later generations to rely upon. I clarify this now to show future learners. Hua Tuo's theory, as stated in the Mai Jing (Pulse Classic), is indeed correct. Wang Shuhe's use of three Cun as the standard has subtle implications; this is the teaching of the Yellow Emperor's orthodox texts, how could it be wrong? Moreover, in ancient times, one skin-width (Fu) was four Cun. Wang Shuhe likely took three finger-widths, which is close in length to the current one Cun and nine Fen. He Xiu's commentary on the Gongyang Zhuan states: Measuring sideways with the hand gives Fu; pressing with the finger gives Cun. This explains the meaning. Furthermore, Yue Ren (Bian Que) lived in the Zhou Dynasty and compiled the Nan Jing using materials from the Ling Shu and Su Wen. The Cun and Chi measurements of his time were based on Zhou dynasty standards. Therefore, Yue Ren adopted one Cun and nine Fen as the fixed standard, reflecting the principle of Heaven being nine and Earth being ten.