帝曰∶诊法何如？岐伯曰∶诊法常以平旦，阴气未动，阳气未散，饮食未进，经脉未盛，络脉调匀，气血
未乱，故可诊有过之脉。
脉者，气血之先形，气血有乖，则现象于脉。惟平旦阴阳气未动散，无饮食助气，而经络之气调匀，故诊
其脉，可知其病在何处，而寿夭可辨也。
切脉动静，而视精明，察五色，观五脏有余不足，六腑强弱，形之盛衰，以此参伍，决死生之分。
切脉动静者，浮沉迟数之类也。视精明、察五色者，人之精神聚于目，气色荣华现于面，观其外即可知内
之脏腑强弱，见其形可知身之盛衰，或形盛脉弱为本虚，形弱脉盛为邪实，推阴阳逆顺、五行生克之理，参伍
以决断生死之分也，更详下文。
夫脉者，血之府也。长则气治，短则气病，数则烦心，大则病进，上盛则气高，下盛则气胀，代则气衰，
细则气少，涩则心痛，浑浑革至如涌泉，病进而色弊，绵绵其去如弦绝，死。
此即脉辨病，而决生死之法也。卫行脉外而主气，营行脉中而主血，故脉为血之府，然即可因之以验气，
何也？盖血主濡之，气主煦之，血随气行，气由血聚，良以阴阳血气，互相为根，不能析离者也。故脉形长者，
知其气之调达而治也；脉短者，知其气郁而病也；脉数者，或因邪郁化火，或因水亏火亢，皆烦心也；若外感
而脉渐大，是邪盛也，若内伤而脉反大，是本元之气不固也，皆知其病增进矣；若脉势上溢，而寸偏旺，则气
上盛，而息必高；若脉势下垂，而尺反大，则气下坠，而腹必胀也；代者，歇止也，其气衰可知，然亦有脏腑
气血结滞者；脉细，则气少矣，然亦有外受湿气者，总因阳气衰少，而尚可治，若非结滞而现代脉，则本元败
为难治矣；脉涩者，气结血瘀，心主血脉，故心痛也；浑浑革至如涌泉者，轻按至数不清，如皮革之状，重按
如涌泉之腾沸，此根元涣散，阴阳升降出入无序，故病进而色弊矣，然犹有鼓动之势，若无力鼓动，而绵绵如
去水之下溜、如琴弦之忽绝无形者，正如残灯忽灭，故死也。
黄帝问道：诊脉的方法是怎样的？岐伯回答说：诊脉通常选择在清晨进行，此时阴气尚未躁动，阳气尚未耗散，病人尚未进食，经脉之气尚未充盛，络脉之气调和均匀，气血运行没有紊乱，因此可以诊断出异常的脉象。
脉是气血状态的外在表现，如果气血出现异常，就会在脉象上显现出来。只有在清晨阴阳之气未动未散、没有饮食助长气机、经络之气调和均匀的时候，通过诊察脉象，才能知道疾病位于何处，并判断病人的寿命长短。
通过切按脉搏的动静变化，观察眼睛的神采，审视面部的五色，考察五脏的有余与不足、六腑的强与弱、形体的盛与衰，将这些情况相互参照比较，从而决断生死界限。
所谓“切脉动静”，指的是浮、沉、迟、数等脉象特征。“视精明、察五色”，是指人的精神汇聚于眼睛，气色荣华显露于面部，观察外部即可了解内部脏腑的强弱，看到形体即可知晓身体的盛衰。例如形体壮盛而脉象虚弱属于本虚，形体虚弱而脉象盛大属于邪实。推究阴阳逆顺、五行生克的道理，综合参伍以决断生死界限，详细内容见下文。
脉，是血液汇聚的府库。脉象长表示气机调畅，脉象短表示气机有病，脉象数表示心烦意乱，脉象大表示病势进展，上部脉盛表示气机上逆，下部脉盛表示气滞腹胀，代脉（脉来中止，不能自还）表示气机衰败，脉象细表示气少，脉象涩表示心痛。脉象浑浑乱乱、急促有力如涌泉般沸腾，说明病势进展且面色败坏；脉象绵绵无力、去时如琴弦突然断绝，主死。
这就是通过脉象辨别疾病并决断生死的方法。卫气行于脉外而主司气，营气行于脉中而主司血，所以脉是血的府库，但也可以借此来验证气的状态，为什么呢？因为血主要起濡养作用，气主要起温煦作用，血随气运行，气由血凝聚而成，确实是因为阴阳、血、气互相为根本，不可分离的缘故。所以脉形长的，可知其气机调达而健康；脉短的，可知其气机郁滞而生病；脉数的，或因邪气郁结化火，或因肾水亏虚导致心火亢盛，都会导致心烦；如果是外感病而脉象逐渐变大，是邪气盛实；如果是内伤病而脉象反而变大，是本元之气不固，这都表明病势在增进；如果脉势向上溢出，寸口脉偏旺，则是气机上盛，呼吸必然高促；如果脉势向下垂坠，尺部脉反而大，则是气机下坠，腹部必然胀满。代脉，指脉搏有歇止，可知其气机衰败，但也有因脏腑气血结滞导致的；脉细，则是气少，但也有因外受湿气影响的，总体是因为阳气衰少，尚可治疗；如果不是因结滞而是出现代脉，则是本元败露，难以治疗；脉涩，是气结血瘀，心主血脉，所以会出现心痛；脉象浑浑乱乱、急促有力如涌泉者，轻按时数不清，如皮革之状，重按时如涌泉般腾沸，这是根元涣散，阴阳升降出入无序，所以病势进展且面色败坏，但尚且有鼓动的势头；如果无力鼓动，脉象绵绵如流水下溜、如琴弦忽然断绝无形，正如残灯忽灭，所以主死。
Huangdi asked: "How is pulse diagnosis conducted?" Qibo replied: "Pulse diagnosis is usually performed in the early morning (Pingdan). At this time, Yin Qi has not yet stirred, Yang Qi has not yet dispersed, food and drink have not been ingested, the Jing Mai (Meridian Vessels) are not yet full, the Luo Mai (Collateral Vessels) are harmonious and uniform, and the Ying Qi (Nutritive Qi) and Xue (Blood) are not yet chaotic. Therefore, abnormal pulses can be diagnosed."
The Mai (Pulse) is the precursor manifestation of Ying Qi and Xue. When Ying Qi and Xue deviate from normality, phenomena appear in the pulse. Only when Yin and Yang Qi are undisturbed and undispersed in the early morning, without dietary assistance to Qi, and with harmonious Qi in the Jing Mai and Luo Mai, can one determine the location of the disease by palpating the pulse and distinguish between longevity and premature death.
By palpating the dynamic changes of the pulse, observing the clarity of the eyes (Shi Jing Ming), examining the five colors of the face, and assessing the excess or deficiency of the Zang Organs, the strength or weakness of the Fu Organs, and the flourishing or declining state of the body form, these factors are cross-referenced (Can Wu) to determine the boundary between life and death.
"Palpating the dynamic changes of the pulse" refers to characteristics such as Floating (Fu), Sinking (Chen), Slow (Chi), and Rapid (Shu). "Observing the clarity of the eyes and examining the five colors" means that human spirit gathers in the eyes, and the luster of Qi and blood manifests on the face. Observing the exterior allows one to know the strength or weakness of the interior Zang Organs; seeing the form allows one to know the flourishing or declining state of the body. For instance, a robust form with a weak pulse indicates root deficiency, while a frail form with a strong pulse indicates pathogenic excess. By deducing the principles of the reversal or smoothness of Yin and Yang, and the generation and restriction of the Five Elements, and cross-referencing them, one decides the division of life and death. Further details follow.
The Mai (Pulse) is the residence (Fu) of Xue (Blood). A long pulse indicates regulated Qi; a short pulse indicates diseased Qi; a rapid pulse indicates vexation of the heart; a large pulse indicates advancing disease; excess at the upper part indicates high Qi (Qi rising); excess at the lower part indicates abdominal distension due to Qi stagnation; a Dai Pulse (Intermittent Pulse) indicates Qi decline; a fine pulse indicates scanty Qi; a choppy pulse indicates heart pain. If the pulse is chaotic and rapid like surging springs, the disease advances and the complexion deteriorates. If the pulse fades away slowly like a broken string, it indicates death.
This is the method of distinguishing disease through the pulse and deciding life and death. Wei Qi (Defensive Qi) moves outside the vessels and governs Qi; Ying Qi (Nutritive Qi) moves inside the vessels and governs Xue. Thus, the vessel is the residence of Xue, yet it can also be used to verify Qi. Why? Because Xue primarily moistens, and Qi primarily warms. Xue follows Qi in its movement, and Qi gathers through Xue. Indeed, Yin and Yang, Xue, and Qi are mutually rooted and cannot be separated. Therefore, a long pulse shape indicates regulated and smooth Qi and health; a short pulse shape indicates stagnant Qi and disease; a rapid pulse may result from pathogenic stagnation transforming into fire, or from Kidney Water deficiency leading to Heart Fire hyperactivity, both causing heart vexation. If an external contraction presents with a gradually enlarging pulse, it indicates pathogenic excess; if an internal injury presents with a surprisingly large pulse, it indicates insecurity of the Yuan Qi (Original Qi). Both indicate advancing disease. If the pulse force overflows upward and the Cun position is particularly vigorous, Qi is excessive above, and respiration must be labored. If the pulse force sinks downward and the Chi position is relatively large, Qi sinks below, and the abdomen must be distended. The Dai pulse involves pauses, indicating Qi decline, though it can also occur due to stagnation of Zang-Fu Qi and Xue. A fine pulse indicates scanty Qi, though it can also result from external dampness invasion; generally, it is due to deficient Yang Qi and is still treatable. However, if a Dai pulse appears without stagnation, it indicates collapse of the Yuan Qi and is difficult to treat. A choppy pulse indicates Qi stagnation and Blood stasis. Since the Heart governs the vessels and blood, heart pain occurs. A chaotic, rapid pulse like surging springs, where light pressure yields indistinguishable beats resembling leather, and heavy pressure feels like boiling springs, indicates scattered Yuan Qi and disorderly ascending/descending and exiting/entering of Yin and Yang, leading to advancing disease and deteriorated complexion. Yet, there is still a pulsating momentum. If there is no forceful pulsation, and the pulse fades slowly like water flowing downhill or like a zither string suddenly breaking without trace, it is like a dying lamp extinguishing, thus indicating death.