夫流注者。为刺法之深源。作针术之大要。是故流者。行也。注者、住也。盖流者要知
经脉
之行流也。注者、谓十二经脉各至本时。皆有虚实邪正之气注于所括之穴也。夫得时谓之开
失时谓之阖。夫开者。针之必除其病。阖者。刺之难愈其疾。可不明此二者乎。况经气内干
五脏。外应支节。针刺之道。经脉为始。若识经脉。则诸行气部分。脉之短长。血气多少。
行之逆顺。祛逐有过补虚泻实。则万举万痊。若夫经脉之源而不知。邪气所在而不辨。往往
病在阳明。反攻少阴。疾在厥阴。却和太阳。遂致贼邪未除。本气受弊。以此推之。经脉之
理不可不通也。昔圣人深虑此者。恐后人劳而少功也。广因闲暇之际。爰取前经以按旧典。
缘柯摘叶。采摭精华以明流注之幽微。庶免讨寻之倦怠。不揣荒拙。列图于后。凡我同声之
者。见其违阙。改而正之。庶行之久远而无弊焉。不亦宜乎。
经脉一周于身。内长一十六丈二尺。人一呼脉行三寸。一吸脉行三寸。呼吸定息。脉行
六寸
计二百七十定息。气可环周。然尽五十荣卫以一万三千五百息。则气脉都行八百一十丈。
如是则应天常度。脉气无不及太过。气象平调。故曰。平人也。
凡刺之理。经脉为始。经脉者。所以能决死生。处百病。调虚实。不可不通也。夫经气
者。
内干五脏。而外络支节。其浮气不循经者。为卫气。精专行于经隧者。为荣气。阴阳相随。
外内相贯。如环之无端。常以平旦为纪。其脉始从中焦手太阴出。注于手阳明。上行注足阳
明。下行至 上。注大指间。与足太阴合。上行抵脾。从脾注心。中循手少阴。出腋下臂。
注小指。合手太阳。上行乘腋出 。内注目内 。上巅下项。合足太阳。循脊下尻。下行注
小趾之端。循足心注足少阴。上行注肾注心。外散于胸中。循手心主脉。出腋下臂。入两筋
之间。入掌中。出中指之端。环注小指次指之端。合手少阳。上行注膻中。散于三焦。从三
焦注胆。出胁注足少阳。下行至 上。复从 注大指间。合足厥阴。上行至肝。从肝上注肺
中。复出于手太阴。此荣气之行也。逆顺之常。荣气之行。常循其经。周身之度。一十六丈
二尺。一日一夜行八百一十丈。计五十度。周于身。卫气则不循其经焉。昼则行阳。夜行于
阴。行于阳者行诸经。行于阴者行诸脏。凡刺之道。须卫气所在。然后迎随。以明补泻。此
之谓也。黄帝内经曰。凡人两手足各有三阴三阳脉。以合为十二经脉也。手之三阴。从脏走
至手。手之三阳。从手走至头。足之三阳。从头下走至足。足之三阴。从足上走入腹。络脉
传注。周流不息。故经脉者。行血气。通阴阳。以荣于身者也。其始从中焦注手太阴阳明。
手阳明注足阳明太阴。足太阴注手少阴太阳。手太阳注足太阳少阴。足少阴注手厥阴少阳。
手少阳注足少阳厥阴。厥阴复还注手太阴。其气常以平旦为纪。以漏水下百刻。昼夜行流。
与天同度。终而复始也。
流注，是针刺疗法的深远源头，也是施针技术的核心要领。因此，“流”指的是运行，“注”指的是停留。所谓“流”，关键在于了解经脉之气的运行流转；所谓“注”，是指十二经脉各自到达其对应的时辰时，虚实、邪正之气会注入该经所属的穴位中。顺应时辰称为“开”，违背时辰称为“阖”。在“开”的时候针刺，必然能祛除疾病；在“阖”的时候针刺，则难以治愈疾患。难道可以不明了这两者吗？况且经气在内联系五脏，在外对应四肢关节。针刺的道理，以经脉为起始。如果认识了经脉，那么关于气血运行的部位、脉道的长短、血气的多少、运行的逆顺，以及祛除有过之邪、补虚泻实的方法，就能做到万举万全、无不痊愈。如果不了解经脉的源头，不辨别邪气所在，往往病在阳明经，却反向针刺少阴经；疾在厥阴经，却去调和太阳经。这样导致贼邪未能清除，本气反而受损。由此推论，经脉的道理不可不通晓。
从前圣人深切忧虑这一点，是担心后人劳而无功。于是趁着闲暇之时，选取前代经典以核对旧有典籍，如同沿树取枝摘叶，采集精华以阐明流注理论的幽微之处，以免寻找探索时的倦怠。不自量力地列出图表在后面。希望志同道合的人，看到其中的缺失，加以改正和纠正，使得这一理论能够长久施行而没有弊端，不也是合适的吗？
经脉在全身循环一周，长度为一十六丈二尺。人每呼气一次，脉气运行三寸；每吸气一次，脉气运行三寸。呼吸定息（一呼一吸之间），脉气运行六寸。共计二百七十次定息，气即可环绕周身。然而，当完成五十周营卫循环，共一万三千五百次呼吸时，气脉总共运行八百一十丈。这样便符合天的常规度数，脉气既不过分不足也不过分有余，气象平和协调，所以称之为“平人”（健康之人）。
大凡针刺的原理，以经脉为起始。经脉，之所以能决断生死，处理各种疾病，调节虚实，是不可不通晓的。经气在内联系五脏，在外联络四肢关节。其中浮散而不循行于经脉的，称为卫气；精纯专一而行于经隧中的，称为荣气（即营气）。阴阳相互跟随，内外贯通，如圆环般没有端点。通常以清晨平旦时刻作为纪始，脉气开始从中焦的手太阴肺经发出，注入手阳明大肠经，上行注入足阳明胃经，下行至足部，注入大脚趾间，与足太阴脾经相合，上行抵达脾脏，从脾脏注入心脏，中间循行手少阴心经，出于腋下臂部，注入小指，与手太阳小肠经相合，上行经过腋窝，出于颈部内侧，注目内眦，上达头顶，下项背，与足太阳膀胱经相合，循脊柱下行至尾骨，下行注入小趾末端，循足心注入足少阴肾经，上行注入肾脏，再注入心脏，外散于胸中，循行手厥阴心包经，出于腋下臂部，进入两筋之间，进入掌中，出于中指末端，环绕注入无名指次指末端，与手少阳三焦经相合，上行注入膻中，散布于三焦，从三焦注入胆经，出于胁肋注入足少阳胆经，下行至足部，再从足部注入大脚趾间，与足厥阴肝经相合，上行至肝脏，从肝脏上注于肺中，又复出到手太阴肺经。这就是荣气的运行规律。逆顺是常态，荣气的运行常遵循经脉，周身长度为十六丈二尺，一日一夜运行八百一十丈，共计五十周，循环于全身。卫气则不循行于经脉之中。白天行于阳经，夜晚行于阴脏。行于阳经时，运行于各条经脉；行于阴脏时，运行于各个脏腑。大凡针刺之道，必须等待卫气所在之处，然后才能运用迎随手法来明确补泻。这就是所说的道理。《黄帝内经》说：凡是人的双手双脚各有三条阴经和三条阳经，配合起来就是十二经脉。手的三条阴经，从内脏走向手部；手的三条阳经，从手部走向头部；足的三条阳经，从头部向下走向足部；足的三条阴经，从足部向上走入腹部。络脉传注，周流不息。所以经脉，是运行血气，沟通阴阳，以滋养身体的。其起始从中焦注入手太阴、手阳明，手阳明注入足阳明、足太阴，足太阴注入手少阴、手太阳，手太阳注入足太阳、足少阴，足少阴注入手厥阴、手少阳，手少阳注入足少阳、足厥阴，足厥阴又返还注入手太阴。其气通常以平旦为纪始，以漏水滴下一百刻计时，昼夜运行流动，与天道相同，终结后又重新开始。
Liu-zhu (Flow and Injection) is the profound source of acupuncture techniques and the major essence of needle manipulation. Therefore, "Liu" (Flow) refers to movement, and "Zhu" (Injection) refers to staying or accumulating. Regarding "Liu," one must understand the flow of Qi through the meridians. Regarding "Zhu," it means that when each of the Twelve Meridians reaches its corresponding time period, there is an injection of Deficient/Excess (Xu-Shi) and Pathogenic/Upright (Xie-Zheng) Qi into the acupoints belonging to that meridian. Adhering to the correct time is called "Kai" (Opening), while missing the time is called "He" (Closing). When needling during "Kai," the disease will surely be removed; when needling during "He," it is difficult to cure the illness. Can one fail to clarify these two aspects? Moreover, Meridian Qi internally connects with the Five Zang Organs and externally corresponds to the limbs and joints. The way of acupuncture and moxibustion begins with the meridians. If one understands the meridians, then regarding the parts where Qi flows, the length of the vessels, the quantity of Blood and Qi, the direction of flow (reverse or smooth), and methods to expel excess and tonify deficiency while draining excess, one can achieve success in every attempt and complete recovery in every case. However, if one does not know the source of the meridians and cannot distinguish the location of pathogenic factors, often when the disease is in the Yangming Meridian, one may wrongly attack the Shaoyin Meridian; when the illness is in the Jueyin Meridian, one may incorrectly harmonize the Taiyang Meridian. This results in the pathogenic evil remaining unremoved while the original Qi suffers damage. From this, we can deduce that the principles of meridians must be thoroughly understood.
In ancient times, the Sages deeply considered this matter, fearing that later generations would labor without merit. Taking advantage of leisure time, they selected previous classics to verify old records, picking branches and leaves from the tree, collecting essences to illuminate the subtle mysteries of Liu-zhu, thereby avoiding the fatigue of searching. Presumptuously presenting diagrams afterwards, I hope those of like mind who see deficiencies will correct them, so that this knowledge may be practiced for a long time without detriment. Is this not appropriate?
The Jing-Mai (Meridians) circulate once around the body, with a total length of sixteen zhang and two chi. With each exhalation, the pulse moves three cun; with each inhalation, the pulse moves three cun. At the moment respiration settles (one breath cycle), the pulse moves six cun. Counting two hundred and seventy settled breaths, Qi can circle the entire body. However, completing fifty cycles of Ying-Qi (Nutritive Qi) and Wei-Qi (Defensive Qi) involves thirteen thousand five hundred breaths, during which Qi and pulses travel a total of eight hundred and ten zhang. In this way, it corresponds to the constant measure of Heaven, ensuring that Pulse Qi is neither insufficient nor excessive, and the physiological state is balanced and harmonious. Thus, it is said: "Ping Ren" (Healthy Person).
The principle of all acupuncture begins with the meridians. The meridians are capable of determining life and death, managing hundreds of diseases, and adjusting deficiency and excess; therefore, they must not be left ununderstood. Meridian Qi internally connects with the Five Zang Organs and externally links to the limbs and joints. The floating Qi that does not follow the meridians is called Wei-Qi (Defensive Qi); the pure and concentrated Qi that travels within the meridian tunnels is called Ying-Qi (Nutritive Qi). Yin and Yang follow each other, penetrating inside and outside, forming a circle without beginning or end. Usually, the cycle starts at dawn (Ping Dan). The pulse originates from the Middle Jiao, emerges from the Hand-Taiyin Lung Meridian, injects into the Hand-Yangming Large Intestine Meridian, ascends to inject into the Foot-Yangming Stomach Meridian, descends to the foot, injects between the big toes, and merges with the Foot-Taiyin Spleen Meridian. It ascends to reach the Spleen, injects from the Spleen into the Heart, follows the Hand-Shaoyin Heart Meridian, emerges from the axilla and arm, injects into the little finger, and merges with the Hand-Taiyang Small Intestine Meridian. It ascends through the armpit, emerges from the neck, enters the inner canthus, ascends to the vertex, descends the nape, and merges with the Foot-Taiyang Bladder Meridian. It follows the spine down to the sacrum, descends to inject into the tip of the little toe, follows the sole of the foot to inject into the Foot-Shaoyin Kidney Meridian, ascends to inject into the Kidney, then into the Heart, scatters externally in the chest, follows the Hand-Jueyin Pericardium Meridian, emerges from the axilla and arm, enters between the two tendons, enters the palm, emerges at the tip of the middle finger, circles to inject into the tip of the ring finger, and merges with the Hand-Shaoyang Sanjiao Meridian. It ascends to inject into the Shanzhong (Chest Center), scatters in the Sanjiao (Triple Burner), injects from the Sanjiao into the Gallbladder Meridian, emerges from the hypochondrium to inject into the Foot-Shaoyang Gallbladder Meridian, descends to the foot, returns from the foot to inject between the big toes, merges with the Foot-Jueyin Liver Meridian, ascends to the Liver, injects from the Liver up into the Lungs, and re-emerges into the Hand-Taiyin Lung Meridian. This is the circulation of Ying-Qi (Nutritive Qi). The normal course is reverse and smooth; Ying-Qi always follows the meridians. The measure of the whole body is sixteen zhang and two chi. In one day and night, it travels eight hundred and ten zhang, counting fifty cycles around the body. Wei-Qi (Defensive Qi), however, does not follow the meridians. During the day, it travels in Yang; at night, it travels in Yin. Traveling in Yang, it moves through the meridians; traveling in Yin, it moves through the Zang Organs. The way of acupuncture requires knowing the location of Wei-Qi before applying following or opposing techniques to clarify tonification and sedation. This is what is meant. The Huangdi Neijing states: Every person has three Yin and three Yang meridians in both hands and feet, combining to form the Twelve Meridians. The three Yin meridians of the hand go from the Zang Organs to the hand; the three Yang meridians of the hand go from the hand to the head; the three Yang meridians of the foot go from the head down to the foot; the three Yin meridians of the foot go from the foot up into the abdomen. Collateral vessels transmit and inject, circulating ceaselessly. Thus, the meridians transport Blood and Qi, connect Yin and Yang, and nourish the body. They start from the Middle Jiao, injecting into the Hand-Taiyin and Hand-Yangming; Hand-Yangming injects into Foot-Yangming and Foot-Taiyin; Foot-Taiyin injects into Hand-Shaoyin and Hand-Taiyang; Hand-Taiyang injects into Foot-Taiyang and Foot-Shaoyin; Foot-Shaoyin injects into Hand-Jueyin and Hand-Shaoyang; Hand-Shaoyang injects into Foot-Shaoyang and Foot-Jueyin; Foot-Jueyin returns to inject into Hand-Taiyin. Its Qi usually takes dawn as the starting point, measured by the clepsydra dripping one hundred ke, flowing day and night, identical to the Heavenly Dao, ending and beginning again.