弦则端直而长，举之应指，按之不移。凡滑大坚搏之属，皆属弦类。不似紧脉之紧急有力，状
如转索弹手，革脉之弦大而数也。（语出张璐。又濒湖体状诗曰∶弦脉迢迢端直长，肝经木旺土应伤；怒气满
胸常欲叫，翳蒙瞳子泪淋浪，相类诗曰∶弦脉端直如丝弦，紧则如绳左右弹；紧言其力弦言象，牢脉
弦长沉伏间。蔡西山曰∶阳搏阴为弦，阴搏阳为紧，阴阳相搏为动，虚寒相搏为革，阴阳分体为散，阴阳不续
为代。）弦为血气不和，气逆邪胜、积聚胀满，寒热胁痛，疟痢疝痹等症（景岳）。然总由于木盛土衰水亏而
成。但以弦多弦少以证胃气之强弱，弦实弦虚以证邪气之虚实，浮弦沉弦以证表里之阴阳，寸弦尺弦以证病气之
升沉。无论所患何症，兼
见何脉，但以和缓有神，不乏胃气，虽弦无碍（张璐）。若弦而劲细强直，是无胃气，岂能治乎。（戴同父曰∶
弦而软，其病轻；弦而硬，其病重。李时珍曰∶浮弦支饮外溢，沉弦悬饮内痛，疟脉自弦，弦数多热，弦迟多
寒，弦大主虚，弦细拘急，阳弦头痛，阴弦腹痛，单弦饮癖，双弦寒痼。若不食者，木来克土，必难治矣。）
弱则沉细软弱，举之如无，按之乃得，小弱分明。凡微濡细小，皆属弱类。不似微脉按之欲绝，
濡脉按之若无，细脉之浮沉皆细也。（语出张璐。又濒湖体状诗曰。弱来无力按之柔，柔细而沉不见浮；阳陷
入阴精血弱，白头尤可少年愁。）弱为阳气衰微。凡见是脉，必须用温补以固其阳，以补胃气。然必兼滑而和，
可卜胃气之未艾。若弱更兼之以涩，并少壮暴病忽见是脉，则为气血交败，多致难治。（素问曰∶脉弱以滑，
是有胃气；脉弱以涩，是谓久病。病后老弱见之顺，平人少年见之逆。仲景曰∶阳陷入阴故恶寒发热。又云∶
弱主筋，沉主骨。阳浮阴弱，血虚筋急，柳氏曰∶气虚则脉弱，寸弱阳虚，尺弱阴虚，关弱胃虚。）
弦脉的特征是端直且长，轻取（举）时指下感觉明显，重按（按）时脉搏位置不移动。凡是滑大、坚搏等脉象，都属于弦脉的类别。这与紧脉的紧急有力不同，紧脉状如转动的绳索弹击手指；也与革脉的弦大而数不同。（这段话出自张璐。另外李时珍在《濒湖脉学》的体状诗中说：弦脉迢迢端直而长，肝经木气过旺会损伤脾土；怒气充满胸中常想大叫，眼睛翳蒙瞳孔流泪汪汪。相类诗中说：弦脉端直像丝弦一样，紧脉则像绳子左右弹手；紧脉描述的是力度，弦脉描述的是形态，牢脉则是弦长且沉伏于间。蔡西山说：阳邪搏击阴分为弦脉，阴邪搏击阳分为紧脉，阴阳相搏为动脉，虚寒相搏为革脉，阴阳分离为散脉，阴阳接续中断为代脉。）弦脉主血气不和、气逆邪胜、积聚胀满、寒热胁痛、疟疾痢疾疝气痹证等症状（出自张景岳）。但根本原因总归是由于木盛土衰水亏而成。可以通过弦脉的多少来证明胃气的强弱，通过弦脉的实虚来证明邪气的虚实，通过浮弦沉弦来证明表里的阴阳，通过寸口弦尺部弦来证明病气的升降。无论患什么病症，兼见什么脉象，只要脉象和缓有神，不失胃气，虽然是弦脉也无妨碍（张璐语）。如果脉象劲细强直，这是没有胃气的表现，怎么能治疗呢？（戴同父说：弦而软的，病情轻；弦而硬的，病情重。李时珍说：浮弦主支饮外溢，沉弦主悬饮内痛，疟疾的脉象自呈弦象，弦数脉多热，弦迟脉多寒，弦大脉主虚，弦细脉主拘急，阳弦头痛，阴弦腹痛，单弦脉主饮癖，双弦脉主寒痼。如果不能进食，是木来克土，必定难治。）
弱脉的特征是沉细软弱，轻取（举）时好像没有，重按（按）才能感觉到，细小虚弱分明。凡是微、濡、细小等脉象，都属于弱脉的类别。这与微脉按之欲绝不同，与濡脉按之若无不同，也与细脉浮沉皆细不同。（这段话出自张璐。另外李时珍在《濒湖脉学》的体状诗中说：弱脉无力，按之柔和，柔细而沉不见浮；阳气陷入阴分导致精血虚弱，老年人尚可理解，年轻人出现此脉则令人忧愁。）弱脉主阳气衰微。凡是见到这种脉象，必须用温补的方法来固护阳气，以补益胃气。然而脉象必须兼有滑象且和缓，才可以推测胃气尚未断绝。如果弱脉再兼见涩象，并且在青壮年突发疾病时突然见到这种脉象，就是气血交败的表现，大多难以治疗。（《素问》说：脉弱而有滑象，是有胃气；脉弱而有涩象，称为久病。病后老弱之人见到此脉为顺证，健康年轻人见到此脉为逆证。张仲景说：阳气陷入阴分所以恶寒发热。又说：弱脉主筋病，沉脉主骨病。阳浮阴弱，血虚导致筋脉拘急。柳氏说：气虚则脉弱，寸口弱为阳虚，尺部弱为阴虚，关部弱为胃虚。）
The Xian pulse (String-like Pulse) is straight, long, and taut. It is felt distinctly upon light palpation (lifting) and remains stable without shifting upon heavy pressure (pressing). Any pulses that are slippery, large, firm, or forceful belong to the category of Xian pulses. This differs from the Jin pulse (Tight Pulse), which is urgent and forceful, feeling like a twisted rope snapping against the fingers; and it also differs from the Ge pulse (Leather Pulse), which is string-like, large, and rapid. (This passage is attributed to Zhang Lu. Additionally, Li Shizhen's "Poem on Pulse Characteristics" in *Binhu Maixue* states: The Xian pulse stretches far, straight and long; when Liver Wood qi is excessive, Spleen Earth is injured; anger fills the chest causing frequent shouting, while eye cataracts and tearing occur. The "Poem on Similar Pulses" states: The Xian pulse is straight like a silk string; the Jin pulse feels like a rope snapping left and right. "Jin" describes its force, "Xian" describes its form, while the Lao pulse is Xian, long, deep, and hidden. Cai Xishan said: Yang fighting Yin produces the Xian pulse; Yin fighting Yang produces the Jin pulse; Yin and Yang fighting each other produce the Dong pulse (Surging/Agitated Pulse); deficiency and cold fighting each other produce the Ge pulse; Yin and Yang separating produce the San pulse (Scattered Pulse); and Yin and Yang failing to continue produce the Dai pulse (Intermittent Pulse).) The Xian pulse indicates disharmony of blood and qi, rebellious qi with victorious pathogenic factors, accumulation and distension, alternating chills and fever, hypochondriac pain, malaria, dysentery, hernia, and bi-syndrome (attributed to Zhang Jingyue). However, the root cause always lies in excessive Wood, deficient Earth, and deficient Water. One can judge the strength of Stomach qi by the degree of the Xian pulse, the excess or deficiency of pathogenic factors by the fullness or emptiness of the pulse, the exterior-internal yin-yang status by superficial or deep Xian pulses, and the rising or sinking of disease qi by radial or ulnar Xian pulses. Regardless of the specific disease or accompanying pulses, as long as the pulse is harmonious and spirited, retaining Stomach qi, a Xian pulse is not detrimental (Zhang Lu). If the pulse is vigorous, thin, strong, and rigid, it indicates the absence of Stomach qi; how can such a condition be treated? (Dai Tongfu said: A soft Xian pulse indicates mild disease; a hard Xian pulse indicates severe disease. Li Shizhen said: Superficial Xian indicates overflowing fluid retention; deep Xian indicates internal pain from suspended fluid retention; malaria pulses are naturally Xian; Xian-rapid pulses indicate much heat; Xian-slow pulses indicate much cold; Xian-large pulses indicate deficiency; Xian-thin pulses indicate stiffness and spasm; Yang-side Xian causes headache; Yin-side Xian causes abdominal pain; single Xian indicates fluid retention and masses; double Xian indicates chronic cold conditions. If the patient cannot eat, it signifies Wood overcoming Earth, which is difficult to treat.)
The Ruo pulse (Weak Pulse) is deep, fine, and weak. It seems absent upon light palpation but is felt only upon heavy pressure, appearing clearly small and weak. Pulses such as Wei (Minute), Ru (Soggy), and Xi (Fine) all belong to the category of Ruo pulses. This differs from the Wei pulse, which feels almost imperceptible upon pressure; the Ru pulse, which feels non-existent upon pressure; and the Xi pulse, which is fine both superficially and deeply. (This passage is attributed to Zhang Lu. Additionally, Li Shizhen's "Poem on Pulse Characteristics" states: The Ruo pulse lacks force and is soft upon pressure; it is soft, fine, and deep, not floating; when Yang sinks into Yin, essence and blood become deficient; this may be understandable in old age but causes sorrow in youth.) The Ruo pulse indicates the decline and weakness of Yang qi. Whenever this pulse is seen, warming and tonifying methods must be used to consolidate Yang and benefit Stomach qi. However, if the pulse is accompanied by a slippery quality and harmony, one may predict that Stomach qi has not yet ceased. If the Ruo pulse is further accompanied by a choppy quality, and appears suddenly in young or robust individuals during acute illness, it indicates a collapse of both qi and blood, making it mostly difficult to treat. (*Suwen* states: A pulse that is weak yet slippery indicates the presence of Stomach qi; a pulse that is weak yet choppy is termed chronic illness. Seeing this pulse after illness in the elderly or weak is favorable; seeing it in healthy youths is unfavorable. Zhang Zhongjing said: When Yang sinks into Yin, there is aversion to cold and fever. He also stated: The Ruo pulse governs tendons; the Shen pulse governs bones. Floating Yang and Weak Yin indicate blood deficiency leading to tendon stiffness. Liu Shi said: Qi deficiency results in a weak pulse; radial weakness indicates Yang deficiency; ulnar weakness indicates Yin deficiency; middle-position weakness indicates Stomach deficiency.)