虚脉迟大而软。按之无有。隐指豁豁然空。崔紫虚云∶形大力薄。其虚可知。主伤暑怔
忡
自汗惊悸发热阴虚腹胀痿痹遗精便泄诸症。经曰血虚脉虚。又曰气来虚微为不及。病在内又
曰久病脉虚者死。若芤脉则大如慈葱与虚脉豁豁然。空不同也。所谓散脉者其形如杨花散漫
。去来无定。息数难齐。无统纪。无约束。涣散不收。稍按便四散不聚。主病为溢饮。为血
耗
。为怔忡。为脱汗。为 肿 。产妇得之生。妊妇得之坠。平人见之死。难经曰散脉独见者
危。柳氏曰∶散为血气。俱虚根本脱离之脉。若两尺见之魂断归冥。心脉洪大微散。肺脉浮
涩微散。独此不妨耳。此散与虚异。而虚又与芤异也。
结脉缓而一止。止无常数。代脉动而中止。不能自还。因而复动。止有常数。脉学云数
而时
止名为促。缓止须将结脉呼。止不能回方是代。结生代死自殊涂。然代为气衰。固云死脉。
而又宜于风家痛极。孕妇霍乱。是代亦有生者。至结脉虽为阴凝痰结积聚痈肿瘕疝诸病。每
见脱血逢此终不免于死者。是又不拘于常数。总之结脉多生代脉多死耳。濒湖曰∶脉一息五
至
肺心脾肝肾五脏之气皆足。五十动而一息。合大衍之数。谓之平脉。反此则止乃见焉。肾气
不能至则四十动一息。肝气不能至。则三十动一息。盖一藏之气衰而代藏之。气代至也。滑
伯仁曰∶若无病羸瘦而脉代者危脉也。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。
虚脉表现为迟、大且柔软。重按时感觉不到脉搏，手指下有一种豁然空虚的感觉。崔紫虚说：脉形虽大但力量薄弱，其虚弱的性质就可以知道了。主病包括伤暑、怔忡、自汗、惊悸、发热、阴虚、腹胀、痿痹、遗精、便泄等各种症状。经典著作中说：血虚则脉虚。又说：脉气来势虚弱微弱称为“不及”，病在内。又说：久病出现虚脉的预后不良（死）。如果芤脉，其形态像慈葱一样中空，与虚脉那种豁然空虚的感觉是不同的。所谓散脉，其形态像杨花散漫无序，来去没有定准，呼吸节律难以整齐，没有统纪，没有约束，涣散不收，稍微按压就向四周散开而不聚拢。主病为溢饮、血耗、怔忡、脱汗、水肿。产妇见到此脉可以生产，孕妇见到此脉会导致流产，健康人见到此脉则预示死亡。《难经》说：散脉单独出现是危险的。柳氏说：散脉是气血俱虚、根本脱离的脉象。如果两尺部出现散脉，说明魂断归冥；心脉洪大微带散象，肺脉浮涩微带散象，唯独这两种情况不妨碍。这是散脉与虚脉不同，而虚脉又与芤脉不同的地方。
结脉表现为缓而时有停顿，停顿没有固定的规律。代脉表现为跳动中止，不能自行恢复，因而再次跳动，停顿有固定的规律。脉学著作说：数脉而时有停顿名为促脉，缓脉而时有停顿称为结脉，停顿后不能立即恢复才是代脉。结脉主生，代脉主死，二者路径不同。然而代脉虽然因气衰而被认为是死脉，但也适宜于风病、剧痛、孕妇霍乱等情况，所以代脉也有生的可能。至于结脉，虽然多见于阴凝、痰结、积聚、痈肿、瘕疝等疾病，但每当遇到失血患者出现此脉时，最终不免于死。这又不拘泥于是否有固定停顿次数。总之，结脉多主生，代脉多主死。李时珍（濒湖）说：一息五至，肺、心、脾、肝、肾五脏之气都充足，五十次跳动为一息，符合大衍之数，称为平脉。与此相反，就会出现停顿。肾气不能到达，则四十次跳动出现一次停顿；肝气不能到达，则三十次跳动出现一次停顿。大概是一个脏器的气衰弱了，由另一个脏器的气代替到达。滑伯仁说：如果没有生病却身体羸瘦而出现代脉，是危重的脉象；如果有病且气血突然受损，气不能接续，只是病脉。伤寒病出现心悸且脉代，用复脉汤主治。妊娠期间脉代，说明胎儿已满百日。代脉的主生死不可不辨别清楚。
The Xu (Deficiency) pulse is slow, large, and soft. Upon heavy pressure, it feels absent; under the finger, there is a hollow, empty sensation. Cui Zixu stated: "Although the form is large, the force is thin; its deficiency can be known." It indicates conditions such as heatstroke, palpitations (Zhenchong), spontaneous sweating, fright palpitations, fever, Yin deficiency, abdominal distension, flaccidity syndromes (Wei Bi), spermatorrhea, and diarrhea. The Classics state: "Blood deficiency leads to a Deficiency pulse." It also states: "When the Qi of the pulse comes weak and faint, it is called 'not reaching' (Bu Ji), indicating disease in the interior." It further states: "For chronic diseases, if the pulse is Deficient, death ensues." In contrast, the Kou (Hollow) pulse feels large like a sweet onion, which differs from the hollow emptiness of the Xu pulse. The so-called San (Scattered) pulse has a form like scattered willow catkins; its coming and going are irregular, the breath count is difficult to align, lacking order and constraint, dissipating and unable to gather. Slight pressure causes it to scatter without coalescence. It indicates conditions such as overflow drinking (Yi Yin), blood depletion, palpitations, collapse sweating, and edema. For parturient women, its appearance indicates delivery; for pregnant women, it indicates miscarriage; for healthy individuals, it indicates death. The *Nan Jing* states: "If the Scattered pulse appears alone, it is perilous." Liu Shi stated: "The Scattered pulse indicates both Blood and Qi are deficient, with the root having detached." If seen at both Chi positions, it signifies the soul departing to the netherworld. However, if the Heart pulse is洪大 (Hong Da, Surging/Large) with slight scattering, or the Lung pulse is Floating and Choppy with slight scattering, these cases are not necessarily adverse. This illustrates that the Scattered pulse differs from the Deficient pulse, and the Deficient pulse differs from the Hollow pulse.
The Jie (Knotted) pulse is slow with occasional pauses, but the pauses have no fixed interval. The Dai (Intermittent) pulse involves a cessation of movement that cannot recover spontaneously, requiring a restart, and the pauses occur at fixed intervals. Pulse studies state: "A rapid pulse with occasional pauses is named Cu (Rapid-Interruption); a slow pulse with occasional pauses is called Jie; only when the pause cannot return immediately is it Dai." Jie generally indicates life, while Dai generally indicates death; their paths differ. However, although Dai is considered a death pulse due to Qi decline, it may also appear in wind disorders, extreme pain, or pregnancy complicated by cholera-like vomiting and diarrhea, meaning Dai can also indicate survival. As for Jie, although it is commonly seen in Yin stagnation, phlegm accumulation, masses, abscesses, hernias, etc., when it appears in patients with severe blood loss, death is often inevitable. This does not strictly adhere to the rule of fixed intervals. In summary, Jie pulses mostly indicate survival, while Dai pulses mostly indicate death. Li Shizhen (Binhu) stated: "Five beats per breath indicate sufficient Qi in the Lungs, Heart, Spleen, Liver, and Kidneys. Fifty movements constitute one breath cycle, conforming to the number of Dayan, termed a Normal pulse. Deviating from this results in pauses. If Kidney Qi fails to reach, a pause occurs after forty movements; if Liver Qi fails to reach, a pause occurs after thirty movements. This implies that when one organ's Qi declines, another organ's Qi takes over to reach." Hua Borin stated: "If a person is emaciated without illness and presents a Dai pulse, it is a critical pulse. If ill with sudden damage to Qi and Blood, where Qi cannot continue, it is merely a pathological pulse. In Taiyang disease with palpitations and a Dai pulse, Fumai Tang (Recovering Pulse Decoction) should be used. During pregnancy, a Dai pulse indicates the fetus is full-term. One must distinguish whether Dai indicates life or death."