《素问·脉要精微论》曰∶“持脉有道，虚静为保。”（切脉之道，贵于精诚，
嫌其扰乱，故必心虚而无他想，身静而不言动，然后可以察脉之微而不失病情也。保者，不失也。若躁
动不安，瞻视不定，轻言谈笑，乱说是非，不惟不能得脉中之巧，适足为旁观者鄙且笑也。）
黄帝曰∶“决死生奈何？”岐伯曰∶“形盛脉细，少气不足以
息者危。（身形肥盛，而脉形细弱，且少气而不足以呼吸，则外有余而
内不足，枝叶盛而根本拔也。故曰，少气不足以息者危。）形瘦脉大，胸中多气者死。
（身形瘦削，而脉形洪大，且胸中多气者，阴不足而阳有余也。孤阳不生，故知必死。）形气相得者生。
（形盛者脉亦盛，形小者脉亦小，则形与脉相得矣。相得者，相合也。）参伍不调者病。（参伍者，数目也。言其
至数不匀，往来无常度，故知必病。）三部九候皆相失者死。（皆相失者，如应浮而沉，应小而大，
违四时之度，失五脏之常者矣。）上下左右之脉相应如参舂者病甚。上下左右相失不可数者死。
（上下左右，即两手之三部九候也。参舂者，实大有力，如杵之舂，故曰病甚。若失其常度，至于急数而
不可数，即八九至之绝脉也，安得不死！）中部之候相减者死。”（
众部虽调，而中部独不及者，为根本败坏，安得生乎！）
The *Suwen: Pulse Essentials and Subtle Discussions* states: "There is a method for holding the pulse; emptiness of mind and stillness are the guarantee." (The art of pulse diagnosis values sincerity and precision, avoiding disturbance. Therefore, one must keep the mind empty without distracting thoughts, and remain physically still without unnecessary movement, so as to perceive the subtleties of the pulse without deviating from the true condition of the disease. 'Guarantee' means not losing [the truth]. If one is restless and uneasy, with wandering eyes, speaking lightly and laughing, or gossiping about right and wrong, one will not only fail to grasp the intricacies of the pulse but will also be despised and laughed at by onlookers.)
Yellow Emperor asked: "How do we determine life and death?" Qibo replied: "If the body is robust but the pulse is fine and thin, and there is shortness of breath insufficient for respiration, the condition is critical. (The physique is obese and robust, yet the pulse form is fine and weak, accompanied by shortness of breath insufficient for breathing. This indicates excess on the exterior and deficiency within, akin to lush branches and leaves but uprooted foundations. Thus, it is said that shortness of breath insufficient for respiration indicates a critical condition.) If the body is emaciated but the pulse is洪大 (hongda, large/vigorous), and there is excessive qi in the chest, death ensues. (The physique is lean and wasted, yet the pulse form is large and vigorous, accompanied by a sensation of excessive qi in the chest. This indicates deficiency of Yin and excess of Yang. Solitary Yang cannot generate life alone; thus, death is certain.) If the body and pulse are harmonious, life ensues. (When the body is robust, the pulse is also robust; when the body is small, the pulse is also small. This constitutes harmony between body and pulse. Harmony means mutual accord.) If the pulses are irregular and uncoordinated, disease exists. ('Canwu' refers to numbers. It means the pulse rate is uneven, lacking a consistent rhythm, indicating the presence of disease.) If the pulses in all three positions and nine regions are lost/disordered, death ensues. (Being 'lost' means, for example, a pulse that should be floating is sunken, or one that should be small is large, violating the rhythms of the four seasons and losing the normal characteristics of the five zang organs.) If the pulses above and below, left and right correspond to each other like pounding with a pestle, the disease is severe. If the pulses above and below are disordered and too rapid to count, death ensues. ('Above and below' refers to the three positions and nine regions of both hands. 'Pounding with a pestle' describes a pulse that is full, large, and forceful, like a pestle striking, indicating severe disease. If the normal rhythm is lost, becoming so rapid and numerous that it cannot be counted—such as eight or nine beats per cycle—it is a pulse of extinction; how can survival be expected?) If the pulse in the middle region is diminished, death ensues. (Although other regions may be regular, if the middle region alone is deficient, the foundation is ruined; how can life be sustained?)"