经络者，人之元气，伏于气血之中，周身流行，昼夜无间，所谓脉也。其脉之直行大隧者为经，其脉之分派交经者
为络，其脉络之支别者，如树之有枝，又以其自直行之脉络，而旁行之者也。人肖天地以有生，其经络亦肖天地之时运
以流行，如每日寅时肺脏生，卯时流入大肠经，辰胃巳脾午心火，未时又到小肠经，申属膀胱酉属肾，戊居包络亥三焦，
子胆丑肝又属肺，十二经脉任流行。十二经之脉，一有壅滞则病，太过、不及则病，外邪入经络亦病。有始在一经，久
而传变，为症多端，其症各有经络。如一头疼也，而有左右之分，前后不同；一眼病也，而有大 、小 、黑珠、白珠、
上下胞之异，当分经络而治。经络不分，倘病在肺经也而用心经药，则肺病不除，徒损其心；病在血分也而用气药，则
气受其伤，而血病益甚。至外邪入经络，而为传变之症，尤不可不分经络。东垣曰∶伤寒邪在太阳经，误用葛根汤，则
引邪入阳明，是葛根汤乃阳明经药，非太阳经药也。由此推之，患病之夭于药者，不知其几许人矣。方书云∶“不明十二
经络，开口动手便错。”诚确论也。世之庸医，辄曰吾大方脉也，非针灸科，何必识穴。曾不思先知经络，后能定穴，穴
可不识，经络亦可不知乎？此其所以为庸也。今所汇之书，经络最晰。穴不混淆，使学人因穴以寻络，因络以寻经，经
络了然，直寻病源，庶用药无惑。仁人君子有实心济世者，当注意于此矣。
经络，是人的元气，潜伏在气血之中，在全身循环流动，昼夜不停，这就是所谓的“脉”。其中，经脉中直行的大通道称为“经”，经脉分支交错的部分称为“络”，而络脉再分出的支脉，就像树木有树枝一样，是从直行的脉络旁侧生长出来的。人效法天地而生，其经络的运行也效法天地的时序变化而循环流转，例如每天寅时肺脏气机生发，卯时流入大肠经，辰时属胃，巳时属脾，午时属心火，未时又流至小肠经，申时属膀胱，酉时属肾，戌时居于心包络，亥时属三焦，子时属胆，丑时属肝，再次回到肺，十二经脉就这样任其流行。十二经脉的脉气，一旦有壅滞就会生病，太过或不及也会生病，外邪侵入经络同样会生病。有的病起初只在一经，时间久了发生传变，症状多种多样，每种症状都对应特定的经络。比如头痛，有左右之分，前后部位也不同；眼病，有大眦、小眦、黑珠（角膜/虹膜）、白珠（巩膜）、上下眼睑的区别，应当区分经络进行治疗。如果不区分经络，假如病在肺经却用心经的药物，那么肺病不能消除，反而徒然损伤心脏；病在血分却用治气的药物，那么气会受到伤害，而血病会更加严重。至于外邪侵入经络导致的传变病症，更不可不区分经络。李东垣说：伤寒邪气在太阳经，误用葛根汤，就会引邪进入阳明经，这说明葛根汤是治疗阳明经疾病的药，而不是治疗太阳经疾病的药。由此推断，因用药不当而早逝的人，不知有多少了。医书说：“如果不明白十二经络，开口动手就会出错。”这确实是确切的言论。世间的庸医，常说我是内科医生，不是针灸科，何必认识穴位。他们不曾想，先懂经络，才能确定穴位，穴位可以不识，但经络也可以不知道吗？这就是他们成为庸医的原因。现在汇编的这本书，经络阐述得最清晰。穴位不混淆，使学习者通过穴位寻找络脉，通过络脉寻找经脉，经络了然于胸，直接寻找病源，这样用药就不会有疑惑。仁德君子如果有真心济世救人的意愿，应当注意这一点。
Jingluo (Meridians and Collaterals) are the Yuan Qi (Primal Qi) of humans, hidden within Blood and Qi, circulating throughout the body without interruption day and night; this is what is referred to as Mai (Vessels). The main straight channels within these vessels are called Jing (Meridians), while the branching and intersecting parts are called Luo (Collaterals); the further branches of the collaterals are like twigs on a tree, extending laterally from the main straight channels. Humans are born by emulating Heaven and Earth, and their Jingluo circulation also follows the temporal rhythms of Heaven and Earth. For instance, at Yin hour (03:00–05:00), Lung Qi generates; at Mao hour (05:00–07:00), it flows into the Large Intestine Meridian; Chen hour (07:00–09:00) belongs to Stomach, Si hour (09:00–11:00) to Spleen, Wu hour (11:00–13:00) to Heart Fire, Wei hour (13:00–15:00) again to Small Intestine Meridian, Shen hour (15:00–17:00) to Bladder, You hour (17:00–19:00) to Kidney, Xu hour (19:00–21:00) resides in Pericardium, Hai hour (21:00–23:00) to Sanjiao (Triple Burner), Zi hour (23:00–01:00) to Gallbladder, Chou hour (01:00–03:00) to Liver, and then back to Lung; thus, the Twelve Primary Meridians circulate freely. If the Qi of any of the Twelve Meridians becomes stagnant, disease occurs; if there is excess or deficiency, disease occurs; and if external pathogens invade the meridians, disease also occurs. Some diseases begin in one meridian and, over time, transmit and transform, resulting in various symptoms, each corresponding to specific meridians. For example, headache may differ by left or right side and anterior or posterior location; eye diseases may vary by inner canthus, outer canthus, black pupil (cornea/iris), white sclera, and upper or lower eyelids. Treatment must distinguish based on meridians. If meridians are not distinguished, treating a Lung Meridian disease with Heart Meridian herbs will fail to resolve the lung condition and merely damage the heart; treating a Blood-level disease with Qi-regulating herbs will injure the Qi and exacerbate the blood disorder. Especially for diseases transmitted due to external pathogens invading the meridians, distinguishing meridians is essential. Li Dongyuan stated: "When Shaoyang pathogen is in the Taiyang Meridian, misusing Gegen Tang (Pueraria Decoction) draws the pathogen into the Yangming Meridian; thus, Gegen Tang is a herb for Yangming Meridian diseases, not Taiyang Meridian diseases." From this, we can infer how many people have died prematurely due to incorrect medication. Medical texts state: "If one does not understand the Twelve Meridians, every opening of the mouth and movement of the hand will be erroneous." This is indeed an accurate statement. Quacks often say, "I am a physician for internal medicine, not acupuncture; why should I know acupoints?" They fail to realize that one must first understand meridians to locate acupoints; can one treat without knowing meridians? This is why they are quacks. The book compiled here clarifies meridians most distinctly, avoiding confusion of acupoints, enabling students to find collaterals via acupoints, meridians via collaterals, and thereby clearly identify the source of disease, ensuring no confusion in medication. Benevolent gentlemen with sincere intentions to save the world should pay attention to this.