细脉小人于微，而常有，细直而软，若丝线之应指，《素问》谓之小，王氏言如莠蓬，
柔也。《脉诀》言往来极微，是微反大于细矣，与经相背又曰∶细来累累细如丝，应指沉沉
无绝期，春夏少年俱不利，秋冬老弱却相宜。
主病 细主血弱气衰，诸虚百损，七情六极，非湿侵腰肾，则伤精汗血。寸主呕吐，关
胀，胃虚，尺主丹田冷。泄痢遗精，阴血耗夺。《脉经》言细为血少气衰，有此证则顺，否
则逆，故吐衄脉得沉细者生，忧劳过度者，脉亦细。
结脉往来缓，时一止复来。《脉诀》言∶或来或去，聚而却还，与结无关。仲景有累累
长竿曰阴结，蔼蔼如车盖曰阳结。《脉经》又有如麻子动摇，旋引旋收，聚散不常者曰结，
主死。此三脉名同实异也。又曰∶结脉缓而时一止，独阴偏胜欲亡阳，浮为气滞沉为积，汗
下分明在主张。
主病 结脉主血凝气滞，老痰结滞内积，外痈肿疝。又曰∶结主阴盛之病，越人曰∶结
甚则积甚，结微则积微，浮结外有痛积，伏结内有积聚。
代脉动而中止，不能自还，困而复动，脉至还入尺，良久方来，脉一息五至，肺心脾肝
脏之气，皆是五十动而一息，合大衍之数，谓之平脉，反此则止，代乃见焉，肾气不能至，
则四十动一止。肝气不能止，则三十动一止。盖一脏之气衰，而他脏之气代至也。经曰∶代
则气衰。滑氏曰∶若无他病，羸瘦脉代者，危脉也。有病而气血乍损，气不能续者，只为病
脉，伤寒心悸脉代者，复脉汤主之，妊娠脉代者，其胎百日，代之生死，不可不辨。李氏括
曰∶数时一止名为促，缓止须将结脉看，止不能回方是代，结生代死自殊涂。又曰∶促结之
无常数，或二动三动一止即来，代脉之止有常数，必根据数而止，还入天中，良久方来也。
主病 代脉先因脏气衰，腹痛泄痢下元亏，或为吐泻中焦病，女子怀胎三月分。《脉经
》曰∶代散者死，主泄及脓血。
细脉比微脉稍大，但形态细小且持续存在，脉形直而柔软，触感如同丝线，《素问》中称之为“小”，王叔和形容其像莠蓬草一样柔弱。《脉诀》中说脉搏往来极其微弱，这实际上是微脉的特征，说明微脉反而比细脉更弱，这与经典记载相违背。又说：细脉来时连续不断，细如丝线，按之深沉而无断绝之时，春夏季节对年轻人不利，秋冬季节对年老体弱者却适宜。
主病 细脉主要主血虚气衰，各种虚损病症，七情过度或六极之症；若非湿气侵袭腰肾，则是精气、汗液或血液的损伤。寸部细脉主呕吐，关部细脉主腹胀及胃虚，尺部细脉主丹田寒冷、泄泻痢疾、遗精及阴血耗竭。《脉经》说细脉代表血少气衰，出现这种脉象与证候相符则为顺证，否则为逆证，所以吐血衄血者若脉象沉细则有生机，忧劳过度者，脉象也会变细。
结脉脉搏来去缓慢，偶尔有一次停顿后恢复跳动。《脉诀》中说：脉搏或来或去，聚集后又返回，这与结脉无关。张仲景提到累累长竿状的称为阴结，蔼蔼如车盖状的称为阳结。《脉经》中又有像麻子动摇，旋转牵引又收回，聚散无常的称为结脉，主死证。这三种脉同名而实质不同。又说：结脉缓而时有一止，是独阴偏胜欲亡阳的表现，浮脉主气滞，沉脉主积块，治疗时发汗与攻下需明确区分主张。
主病 结脉主血凝气滞，老痰结滞内积，以及外部的痈肿疝气。又说：结脉主阴盛之病，扁鹊（越人）说：结脉甚则积聚重，结脉微则积聚轻，浮结脉外部有痛性积聚，伏结脉内部有积聚。
代脉脉搏跳动中途停止，不能自行恢复，困顿后才再次跳动，脉搏回到尺部，很久之后才再次到来。正常脉搏一息五至，肺心脾肝四脏之气，都是五十次跳动为一息，符合大衍之数，称为平脉（正常脉象），与此相反出现停顿，代脉就显现了。肾气不足，则四十次跳动停一次。肝气不足，则三十次跳动停一次。这是因为一脏之气衰弱，而其他脏之气代为至也。经典说：代脉表示气衰。滑寿说：若无其他疾病，身体消瘦而出现代脉，是危重脉象。若有疾病导致气血暂时受损，气不能接续，只是病脉。伤寒心悸出现代脉，用复脉汤主治；妊娠出现代脉，可能是怀孕百日所致，代脉关乎生死，不可不辨别。李氏概括说：数脉时一止名为促脉，缓脉时一止应看作结脉，停止后不能立即回复才是代脉，结脉主生代脉主死，二者路径殊异。又说：促脉和结脉的停止没有固定规律，有时两动三动停一次随即恢复，代脉的停止有固定规律，必须依据次数而停止，脉搏还入天中部位，很久之后才来。
主病 代脉首先因脏气衰弱，腹痛泄痢下元亏虚，或者是吐泻导致的中焦病变，女子怀孕三个月时也可能出现。《脉经》说：代脉兼见散脉者死，主泄泻及脓血便。
The Xi (Fine) pulse is slightly larger than the Wei (Minute) pulse but remains consistently fine and continuous. Its shape is straight yet soft, feeling like a silk thread under the fingers. The *Suwen* (Plain Questions) refers to it as "Xiao" (Small), while Wang Shuhe describes it as being as soft as weeds. The *Maixue* (Pulse Classic) states that the pulse comes and goes with extreme minuteness; this actually describes the Wei pulse, implying that the Wei pulse is finer than the Xi pulse, which contradicts the classics. It is also stated: "When the Xi pulse comes continuously, thin as silk, pressing deeply without interruption, it is unfavorable for youths in Spring and Summer, but suitable for the elderly and weak in Autumn and Winter."
Main Pathologies: The Xi pulse primarily indicates deficiency of Blood and decline of Qi, various deficiency syndromes, excessive Seven Emotions or Six Extremes. It signifies either Dampness invading the waist and Kidneys, or injury to Essence, Sweat, and Blood. At the Cun position, it indicates vomiting; at the Guan position, abdominal distension and Stomach deficiency; at the Chi position, coldness in the Dantian, diarrhea/dysentery, spermatorrhea, and depletion of Yin Blood. The *Maijing* (Classic of Pulses) states that Xi indicates little Blood and declining Qi; if symptoms match this pulse, it is a favorable sign (Shun); otherwise, it is unfavorable (Ni). Thus, patients with hematemesis or epistaxis who have a deep and fine pulse may survive, while those overworked also exhibit a fine pulse.
The Jie (Knotted) pulse is slow in its coming and going, occasionally pausing before resuming. The *Maixue* states: "Coming and going irregularly, gathering then returning," which is unrelated to the Jie pulse. Zhang Zhongjing described a pulse resembling linked long poles as Yin Jie (Yin Knot), and one resembling a chariot canopy as Yang Jie (Yang Knot). The *Maijing* also describes a pulse shaking like hemp seeds, rotating and retracting, with irregular gathering and scattering as Jie, which indicates death. These three share the same name but differ in substance. It is further stated: "The Jie pulse is slow with occasional pauses, indicating excess Yin threatening Yang loss. Floating indicates Qi stagnation, sinking indicates accumulation; treatment must clearly distinguish between sweating and purging methods."
Main Pathologies: The Jie pulse indicates Blood coagulation and Qi stagnation, internal accumulation of old Phlegm knots, and external carbuncles or hernias. It is also said: "Jie indicates diseases of Yin excess." Yue Ren (Bian Que) stated: "Severe Jie implies severe accumulation; mild Jie implies mild accumulation. Floating Jie indicates external painful accumulations; Hidden Jie indicates internal accumulations."
The Dai (Intermittent) pulse stops during movement and cannot recover spontaneously; after a period of exhaustion, it moves again. The pulse returns to the Chi position and arrives only after a long interval. A normal pulse beats five times per respiratory cycle. The Qi of the Lung, Heart, Spleen, and Liver all complete fifty beats per cycle, conforming to the number of Da Yan (Great Expansion), known as the Ping Mai (Normal Pulse). Deviation from this results in pauses, revealing the Dai pulse. If Kidney Qi fails, there is a pause every forty beats. If Liver Qi fails, there is a pause every thirty beats. This occurs because when the Qi of one Zang organ declines, the Qi of another organ takes over (Dai). The Classics state: "Dai indicates Qi decline." Hua Shi (Hua Shou) said: "If there are no other diseases, a emaciated patient with a Dai pulse has a critical prognosis." If disease causes temporary damage to Qi and Blood, preventing continuity, it is merely a pathological pulse. In Taiyang disease with palpitations and a Dai pulse, Fumai Tang (Restore the Pulse Decoction) is indicated. In pregnancy, a Dai pulse may indicate fetal development around one hundred days; whether Dai indicates life or death must be distinguished. Li Shi summarized: "A rapid pulse with occasional pauses is Cu (Rapid-Intermittent); a slow pulse with occasional pauses should be viewed as Jie; only when the pause does not immediately return is it Dai. Jie suggests survival, Dai suggests death; their paths are distinct." He further stated: "Cu and Jie pulses have irregular pause patterns, stopping after two or three beats and resuming quickly. Dai pulses have regular pause patterns, stopping according to a fixed count, returning to the Tianzhong area, and arriving only after a long delay."
Main Pathologies: The Dai pulse first arises from Zang Qi decline, abdominal pain, dysentery, and deficiency of the Lower Yuan. It may also result from vomiting and diarrhea affecting the Middle Jiao, or occur in women during the third month of pregnancy. The *Maijing* states: "Dai combined with San (Scattered) indicates death, primarily associated with diarrhea and pus/blood in stools."