Library

[Body and Image] The Micro Pulse (Wei Mai, 微脉) is extremely fine and extremely soft; it seems to exist yet not exist, appearing as if about to cease but not actually ceasing.

[Indicated Diseases] The blurred image of the Micro Pulse indicates a severe depletion of Qi and Blood. If found at the Left Cun position, it indicates fright and timidity; if found at the Right Cun position, it indicates shortness of breath. If found at the Left Guan position, it indicates cold-induced spasms; if found at the Right Guan position, it indicates cold in the Stomach. If found at the Left Chi position, it indicates exhaustion of marrow and essence; if found at the Right Chi position, it indicates failure of Yang Qi and life-threatening condition.

[Commentary] The term "Micro" implies seeming to exist yet not existing. Its image is extremely fine and soft. Since ancient people paired "dust" with "micro," one can imagine its extreme fineness and softness. Zhang Zhongjing said, "Like floating fat on soup broth," describing its softness and lack of strength. "Like a spider's silk," describing its fineness and difficulty to see. Therefore, the ancients said, "Seeming to exist yet not existing, appearing as if about to cease but not actually ceasing." These eight characters best capture the spirit of the Micro Pulse. If the practitioner's mind is restless and fails to achieve emptiness and stillness, and suddenly takes the pulse, it may be impossible to detect. Laypeople, failing to understand the true meaning of the Micro Pulse, often conflate "Micro" and "Fine" whenever they see a fine pulse, which is imprecise language. Light pressure reveals it as non-existent, hence indicating decline of Yang Qi; heavy pressure reveals it as nearly ceasing, hence indicating exhaustion of Yin Qi. In chronic diseases, this pulse is mostly incurable, signifying that Zheng Qi (Upright Qi) is about to perish. In acute diseases, survival is still possible, signifying that pathogenic factors are not yet deep or severe. Li Shizhen said: "The Micro Pulse primarily indicates diseases of long-standing deficiency and weak blood. Yang Micro leads to aversion to cold; Yin Micro leads to fever. Without vigorous tonification, recovery is difficult." Gao Yangsheng said: "Long-standing deficiency leads to metrorrhagia and leukorrhea; prolonged leakage causes bones to wither." This is insufficient to generalize all diseases indicated by the Micro Pulse.

In measurement, ten "Micros" equal one "Hu"; ten "Hus" equal one "Si" (thread); ten "Sis" equal one "Hao"; ten "Haos" equal one "Li". By deduction, when one "Li" is divided into ten thousand parts, only then is it called "Micro." Thus, the minuteness and invisibility of the Micro Pulse can be understood.

[Body and Image] The Fine Pulse (Xi Mai, 细脉) is straight, soft, and continuous; its shape resembles a thread, being more distinct than the Micro Pulse.

[Indicated Diseases] The Fine Pulse indicates Qi deficiency and various consumptive disorders. If located at the Left Cun, it indicates palpitations and insomnia. If located at the Right Cun, it indicates vomiting and timidity. If entering the Left Guan, it indicates exhaustion of Liver Yin. If entering the Right Guan, it indicates Stomach deficiency and distension. If at the Left Chi, it indicates diarrhea, dysentery, and spermatorrhea. If at the Right Chi, it indicates coldness and fatigue of the Lower Yuan (Kidney and Mingmen).

[Commentary] The meaning of "Fine" is small, thin, and resembling a thread. The Micro Pulse is blurred and hard to see, whereas the Fine Pulse is distinct and easy to see; thus, the Fine Pulse is slightly larger than the Micro Pulse. Apocryphal texts claim it is "extremely fine," which describes the Micro Pulse, not the Fine Pulse. Wang Xuanyuan said: "Resembling weed fluff," skillfully depicting its soft and fine state. Wang Shuhe's *Mai Jing* states: "The Fine Pulse indicates little blood and declining Qi. With these symptoms, the pulse matches the disease (Shun/Smooth); without these symptoms, it does not match (Ni/Opposing)." Therefore, patients with vomiting, diarrhea, or blood loss who present with a Deep-Fine pulse have a chance of survival. People who overwork and worry often have Fine pulses because they have damaged their own Qi and Blood. During Spring and Summer, young and strong people should not exhibit a Fine pulse, as it contradicts the season and their constitution. In Autumn and Winter, old and weak people are exempt from this prohibition.

Generally, both the Fine and Micro Pulses are signs of residual Yang Qi decline. The *Nei Jing* says: "Qi provides warmth." Without warm-tonifying treatment, how can the scattered original Qi be restored? I have seen patients with consumption whose pulses were Fine yet whose bodies were constantly hot. Physicians, failing to investigate the root cause, administered cooling agents. What difference is there between hating drunkenness and forcing wine? This causes the True Yang to scatter and fail, leading to anorexia, upper vomiting, and lower diarrhea, thereby hastening death. The *Su Wen* says: "Excessive Fire consumes Qi; Moderate Fire generates Qi." Without Moderate Fire, humans cannot circulate the San Jiao (Triple Burner) or ripen and transform food and water. Those who do not thoroughly understand this cannot wield the authority of life and death. However, in consumptive diseases, the Fine and Rapid pulses must not appear together; if they do, death is certain. Fine indicates Qi decline; Rapid indicates Blood deterioration. When Qi and Blood are both exhausted, the lifespan is short. Even if Huan Bian (metaphor for skilled physicians like Hua Tuo and Bian Que) were to treat it, there would be no day of revival.