《征四失论》曰∶诊不知阴阳逆从之理，此治之一失也。受师不卒，妄作杂术，谬
言为道，更名自功，妄用砭石，后遗身咎，此治之二失也。不适贫富贵贱之居，坐之
薄浓，形之寒温，不适饮食之宜，不别人之勇怯，不知比类，足以自乱，不足以自
明，此治之三失也。诊病不问其始，忧患饮食之失节，起居之过度，或伤于毒，不
先言此，卒持寸口，何病能中，妄言作名，为粗所穷，此治之四失也。（第一失者，不知阴阳
逆顺之理也。阴阳逆顺之理，非止一端，左手人迎为阳，春夏洪大为顺，沉细为逆，右手气口为阴，秋冬沉细为
顺，洪大为逆，男子左手脉大为顺，阴脉为逆，阴病见阳脉为顺，阴脉为逆，内伤阳病见阳脉为顺，阴脉为逆，
阴病见阴脉为顺，阳脉为逆。又色见上下左右各在其要，上为逆，下为从；女子右为逆，左为从；男子左为逆，右
为从。第二失者，不受师术之正，妄效杂术之邪，以非为是，苟用砭石也。第三失者，不适病患之情，不明此
类之义也。第四失者，不究始时致病之由，妄持寸口之脉，不中病情伪指病名也。）
《阴阳类论篇》曰∶三阳为经，二阳为维，一阳为游部，此知五脏终始。三阳为
表，二阳为里，一阴至绝作朔晦，却具合以正其理。（此言六经为人身之表里，以太阳、太阴为
贵也。三阳者，足太阳膀胱经也。从目内 上头分为四道，下项并正别脉，上下六道，以行于背为人身之大经，
二阳者，足阳明胃经也，从鼻起下咽，分为四道，并正别脉。六道上下，行腹为人身之维系。一阳者，足少阳
胆经也。起自外 络头，分为四道，下缺盆并正别脉，六道上下，为人身之游行诸部者也。曰经，曰维，曰游部，
此可以知五脏终始赖此三经以为之表也。三阳为之表，则二阴为之里，二阴者，足少阴肾经也。二阳为之表，则
三阴为之里，三阴者，足太阴脾经也。一阳为之表，则一阴为之里，一阴者，足厥阴肝经也。太阴为正阴，而
次少为少阴，又次为厥阴，太阳为正阳，而次少为少阳，又次为阳明，以其气有多少异用，故各有三者之分耳。然
少太之义易知，而阳明厥阴之义难释，足之十二经合于十二月，故寅者正月之生阳也，主左足之少阳，六月建
未则为右足之少阳，皆两足第四指脉气所行也。二月建卯，主左足之太阳，五月建午则为右足之太阳，皆足小
指外侧已上脉气所行也。三月建辰，主左足之阳明，四月建巳则为右足之阳明，皆两足次指已上脉气所行也。
然正二五六月为少阳太阳，而三四为辰巳月，居于其中，则彼两阳合明于其前，故曰阳明也。七月建申，主阴之
生主右足之少阴，而十二月建丑则为左足之少阴，皆两足心以上脉气所行也。八月建酉，主右足之太阴，而十
二月建子，则为左足之太阴，皆两足大指内侧以上脉气所行也。九月建戌，主右足之厥阴，而十月建亥则为左
足之厥阴，皆两足大指外侧以上脉气所行也。然七、八、十一、十二月为少阴、太阴，而九、十为戌亥月，则为
两足之阴已尽，故曰厥阴也。厥者，尽也。而应之者戌亥，则一阴几于绝矣。岂知一阴至绝而有复作之理，朔
晦相生之妙，却具于其中，盖阴尽为晦，阴生为朔，气尽为晦，气生为朔，既见其晦，又见其朔，厥阴之绝，而
复作合，当以彼晦朔之妙，而正此厥阴之理也。正者，证也。）三阳为父，二阳为卫，一阳为纪。三阴
为母，二阴为雌，一阴为独使。（三阳者，即太阳也。太阳为表之经，覆庇群生，尊犹父也。二阳者，即
阳明也。阳明为表之维，捍卫诸部，所以为卫也。一阳者，即少阳也。少阳为表之游部，布络诸经，所以为纪
也。三阴者，即太阴也。太阴为里之经，长养诸经，尊犹母也。二阴者，即少阴也。少阴为里之维，生由此始，
所以为维也。一阴者，即厥阴也。厥阴为里之游部，将
军谋虑，所以为独使也。）
《征四失论》说：诊病时不懂得阴阳逆顺的道理，这是治疗上的第一种失误。师承学业没有完成，就胡乱采用各种杂术，把错误的言论当作正道，改名换姓以夸耀自己的功劳，妄自使用砭石疗法，从而给身体留下祸患，这是治疗上的第二种失误。不能适应患者贫富贵贱的生活环境，坐卧的厚薄软硬，体质的寒热温凉，不能适应饮食的适宜与否，不能分辨人的勇敢与怯懦，不知道运用类比推理的方法，足以使自己混乱，不足以让自己明白，这是治疗上的第三种失误。诊病时不问明发病的起因，如忧患、饮食失节、起居过度，或者是否受到毒物伤害，如果不先说明这些情况，突然只切按寸口脉，怎么能准确判断疾病？胡乱编造病名，被粗疏的医术所困窘，这是治疗上的第四种失误。（第一种失误，是不懂阴阳逆顺的道理。阴阳逆顺的道理，不止一个方面：左手人迎脉属阳，春夏季节洪大脉为顺证，沉细脉为逆证；右手气口脉属阴，秋冬季节沉细脉为顺证，洪大脉为逆证。男子左手脉大为顺证，阴脉为逆证；阴病见到阳脉为顺证，阴脉为逆证；内伤导致阳病见到阳脉为顺证，阴脉为逆证；阴病见到阴脉为顺证，阳脉为逆证。另外，面色显现的部位上下左右各有其关键所在，上为逆证，下为顺证；女子右侧为逆证，左侧为顺证；男子左侧为逆证，右侧为顺证。第二种失误，是不接受老师正统的医术，胡乱效仿杂术的邪道，以非为是，苟且使用砭石。第三种失误，是不能适应病患的具体情况，不明白这类医理的含义。第四种失误，是不探究最初致病的原因，妄自切按寸口脉，不能符合病情，胡乱指认病名。）
《阴阳类论篇》说：三阳经作为经脉主干，二阳经作为维系网络，一阳经作为游行各部，由此可以了解五脏的终始规律。三阳经位于体表，二阳经位于体内，一阴经发展到极致就像月末晦日一样（阴尽），反过来结合朔日初生之理来校正其道理。（这里论述六经是人身的表里关系，以太阳经和太阴经为尊贵。所谓三阳，是指足太阳膀胱经。从目内眦上行至头部，分为四条道路，下行至颈部，合并正脉和别脉，共六道经脉，在背部运行，是人身的重大经脉。所谓二阳，是指足阳明胃经，从鼻部起始下行至咽喉，分为四条道路，合并正脉和别脉，六道经脉上下运行，在腹部行走，是人身的维系纽带。所谓一阳，是指足少阳胆经。起自外眼角，联络头部，分为四条道路，下行至缺盆，合并正脉和别脉，六道经脉上下运行，是人身游行各部的经脉。称为“经”、“维”、“游部”，由此可知五脏的终始依赖这三条经脉作为表象。三阳经作为表，则二阴经作为里；二阴经，即足少阴肾经。二阳经作为表，则三阴经作为里；三阴经，即足太阴脾经。一阳经作为表，则一阴经作为里；一阴经，即足厥阴肝经。太阴为正阴，其次为少阴，再次为厥阴；太阳为正阳，其次为少阳，再次为阳明，因为它们的阳气多少不同、功用各异，所以各自分为三类。然而少阴、太阴的意义容易理解，而阳明、厥阴的意义难以解释。足部的十二经脉对应十二个月份，所以寅月是正月，代表生发的阳气，主左足的少阳经；六月建未，则代表右足的少阳经，这两处都是足部第四趾以上脉气运行的部位。二月建卯，主左足的太阳经；五月建午，则代表右足的太阳经，这两处都是足小指外侧以上脉气运行的部位。三月建辰，主左足的阳明经；四月建巳，则代表右足的阳明经，这两处都是足部第二趾以上脉气运行的部位。然而正、二、五、六月分别为少阳、太阳，而三、四月为辰、巳月，居于其中，那么前两个阳经合明于此，所以称为阳明经。七月建申，主阴气的生发，主右足的少阴经；十二月建丑，则代表左足的少阴经，这两处都是足心以上脉气运行的部位。八月建酉，主右足的太阴经；十一月建子，则代表左足的太阴经，这两处都是足大指内侧以上脉气运行的部位。九月建戌，主右足的厥阴经；十月建亥，则代表左足的厥阴经，这两处都是足大指外侧以上脉气运行的部位。然而七、八、十一、十二月分别为少阴、太阴，而九、十月为戌、亥月，此时两足的阴气已经穷尽，所以称为厥阴。厥，就是尽的意思。与之相应的戌、亥月，一阴之气几乎断绝了。哪里知道一阴经发展到极致却有着复生的道理，这正是朔日与晦日相生的奥妙，这种道理蕴含在其中。大概阴气穷尽称为晦，阴气生发称为朔，气机穷尽称为晦，气机生发称为朔，既然看到了晦暗，又看到了朔生，厥阴经的断绝与复生相合，应当用晦朔相生的奥妙，来校正厥阴经的道理。正，就是证验的意思。）三阳经如同父亲，二阳经如同卫护，一阳经如同纲纪。三阴经如同母亲，二阴经如同雌性，一阴经如同独行的使者。（三阳经，就是太阳经。太阳经是体表的经脉，覆盖庇护众生，尊贵犹如父亲。二阳经，就是阳明经。阳明经是体表的维系，捍卫各个部位，所以称为卫。一阳经，就是少阳经。少阳经是体表的游行部分，布散络脉于各条经脉，所以称为纲纪。三阴经，就是太阴经。太阴经是体内的经脉，长养各条经脉，尊贵犹如母亲。二阴经，就是少阴经。少阴经是体内的维系，生命由此开始，所以称为维系。一阴经，就是厥阴经。厥阴经是体内的游行部分，如同将军谋划思虑，所以称为独行的使者。）
The "Treatise on the Four Failures in Diagnosis" states: Failing to understand the principles of Yin and Yang, as well as their normal (Shun) and inverted (Ni) states during diagnosis, constitutes the first failure in treatment. If one has not completed their apprenticeship under a teacher but recklessly employs miscellaneous techniques, falsely presenting errors as the Way, changing names to claim personal merit, and improperly using Bian stones (stone scalpels), thereby leaving harm to the body, this constitutes the second failure in treatment. If one fails to adapt to the living conditions associated with poverty, wealth, or nobility; the thickness or thinness of seating surfaces; the cold or warmth of the patient's constitution; nor adapts to dietary suitability, nor distinguishes between courage and timidity in individuals, and lacks the ability to use analogical reasoning—sufficient to cause self-confusion and insufficient for self-clarity—this constitutes the third failure in treatment. When diagnosing illness without asking about its onset, such as emotional distress, dietary irregularities, excessive lifestyle habits, or exposure to toxins, and if these factors are not addressed beforehand, but instead one abruptly palpates only the Cun Kou pulse (radial artery at the wrist), how can the disease be accurately identified? Making reckless claims and fabricating disease names, becoming trapped by crude medical practices, constitutes the fourth failure in treatment. (The first failure is ignorance of the principles of Yin-Yang inversion and compliance. These principles are manifold: The Ren Ying pulse (carotid artery) on the left hand belongs to Yang; a洪大 (Hóng Dà, large and forceful) pulse in Spring and Summer indicates compliance (Shun), while a 沉细 (Chén Xì, deep and fine) pulse indicates inversion (Ni). The Qi Kou pulse (radial artery) on the right hand belongs to Yin; a 沉细 (deep and fine) pulse in Autumn and Winter indicates compliance, while a 洪大 (large and forceful) pulse indicates inversion. For men, a large pulse on the left hand is compliant, while a Yin pulse is inverted; seeing a Yang pulse in a Yin disease is compliant, while a Yin pulse is inverted; for internal injuries manifesting as Yang diseases, seeing a Yang pulse is compliant, while a Yin pulse is inverted; seeing a Yin pulse in a Yin disease is compliant, while a Yang pulse is inverted. Furthermore, the appearance of facial colors in upper/lower or left/right positions has specific significance: appearing above indicates inversion, below indicates compliance; for women, the right side indicates inversion, the left indicates compliance; for men, the left side indicates inversion, the right indicates compliance. The second failure is rejecting orthodox teachings from one's master and blindly imitating heterodox miscellaneous arts, treating falsehood as truth, and arbitrarily using Bian stones. The third failure is failing to adapt to the patient's specific condition and misunderstanding the meaning of such classifications. The fourth failure is neglecting to investigate the initial causes of the disease, recklessly palpating the Cun Kou pulse, failing to match the clinical presentation, and falsely naming the disease.)
The "Treatise on Yin-Yang Categories" states: The Three Yang meridians serve as the main channels (Jing), the Two Yang meridians serve as the supporting network (Wei), and the One Yang meridian serves as the wandering department (You Bu); through this, one can understand the beginning and end of the Five Zang organs. The Three Yang meridians are exterior, the Two Yang meridians are interior, and when the One Yin meridian reaches its extremity, it resembles the last day of the lunar month (Hui/Darkness); conversely, combining this with the principle of the new moon (Shuo/New Moon) allows one to rectify its logic. (This passage discusses the exterior-interior relationship of the Six Meridians, emphasizing the importance of the Taiyang and Taiyin meridians. "Three Yang" refers to the Foot-Taiyang Bladder Meridian. It rises from the inner canthus to the head, dividing into four paths, descends to the neck, merging with the main and collateral branches, forming six pathways that run along the back, serving as the major channel of the body. "Two Yang" refers to the Foot-Yangming Stomach Meridian, starting from the nose, descending to the throat, dividing into four paths, merging with main and collateral branches, running up and down in six pathways along the abdomen, serving as the sustaining link of the body. "One Yang" refers to the Foot-Shaoyang Gallbladder Meridian, originating from the outer canthus, connecting to the head, dividing into four paths, descending to the supraclavicular fossa, merging with main and collateral branches, running up and down in six pathways, serving as the wandering department throughout the body. Being called Jing, Wei, and You Bu allows one to know that the beginning and end of the Five Zang organs rely on these three meridians as their exterior manifestation. With Three Yang as the exterior, Two Yin become the interior; Two Yin refers to the Foot-Shaoyin Kidney Meridian. With Two Yang as the exterior, Three Yin become the interior; Three Yin refers to the Foot-Taiyin Spleen Meridian. With One Yang as the exterior, One Yin becomes the interior; One Yin refers to the Foot-Jueyin Liver Meridian. Taiyin is the Principal Yin, followed by Shaoyin, then Jueyin; Taiyang is the Principal Yang, followed by Shaoyang, then Yangming. Because their Qi quantities and functions differ, they are divided into these three categories. However, the meanings of Shaoyin and Taiyin are easy to understand, whereas those of Yangming and Jueyin are difficult to explain. The twelve foot meridians correspond to the twelve months. Yin (the first month) represents the generating Yang Qi, governing the Left-Foot Shaoyang; Wei (the sixth month) governs the Right-Foot Shaoyang; both are sites where Qi flows above the fourth toe. Mao (the second month) governs the Left-Foot Taiyang; Wu (the fifth month) governs the Right-Foot Taiyang; both are sites where Qi flows above the lateral aspect of the little toe. Chen (the third month) governs the Left-Foot Yangming; Si (the fourth month) governs the Right-Foot Yangming; both are sites where Qi flows above the second toe. Since Zheng, Er, Wu, and Liu months correspond to Shaoyang and Taiyang, while San and Si months lie within them, the preceding two Yang meridians combine to illuminate this region, hence it is called Yangming. Shen (the seventh month) marks the generation of Yin, governing the Right-Foot Shaoyin; Chou (the twelfth month) governs the Left-Foot Shaoyin; both are sites where Qi flows above the soles of the feet. You (the eighth month) governs the Right-Foot Taiyin; Zi (the eleventh month) governs the Left-Foot Taiyin; both are sites where Qi flows above the medial aspect of the big toe. Xu (the ninth month) governs the Right-Foot Jueyin; Hai (the tenth month) governs the Left-Foot Jueyin; both are sites where Qi flows above the lateral aspect of the big toe. Since the seventh, eighth, eleventh, and twelfth months correspond to Shaoyin and Taiyin, while the ninth and tenth months (Xu and Hai) represent the exhaustion of Yin in both feet, it is called Jueyin. Jue means exhaustion. Corresponding to Xu and Hai, the Qi of One Yin is nearly extinct. Yet, one must realize that when One Yin reaches its extremity, there is a principle of regeneration, embodying the wonder of Shuo and Hui相生 (mutual generation). Essentially, Yin exhaustion is Hui (Darkness), Yin generation is Shuo (New Moon); Qi exhaustion is Hui, Qi generation is Shuo. Having seen the Darkness and then the New Moon, the extinction and regeneration of Jueyin align; one should use the wonder of Hui and Shuo to rectify the principle of Jueyin. "Zheng" here means verification/evidence.) The Three Yang meridians are like fathers, the Two Yang meridians are like guards, and the One Yang meridian is like the discipline/standard. The Three Yin meridians are like mothers, the Two Yin meridians are like females, and the One Yin meridian is like the solitary messenger. (Three Yang refers to Taiyang. Taiyang is the exterior channel, covering and protecting all living beings, respected like a father. Two Yang refers to Yangming. Yangming is the exterior support, defending various parts, thus serving as the guard. One Yang refers to Shaoyang. Shaoyang is the exterior wandering department, distributing collaterals to various meridians, thus serving as the standard/discipline. Three Yin refers to Taiyin. Taiyin is the interior channel, nourishing various meridians, respected like a mother. Two Yin refers to Shaoyin. Shaoyin is the interior support, from which life begins, thus serving as the sustainer. One Yin refers to Jueyin. Jueyin is the interior wandering department, akin to a general planning strategies, thus serving as the solitary messenger.)