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[Body and Image] The Ru (Soft) pulse is fine and soft, appearing in the floating layer; it can be felt with light pressure (lifting), but feels empty upon heavy pressure (pressing).

[Main Pathology] The Ru pulse primarily indicates Yin deficiency, exhaustion of marrow, and injury to essence. If seen at the Left Cun position, it indicates forgetfulness, palpitations, and fright. If seen at the Right Cun position, it indicates deficient interstices and spontaneous sweating. If encountered at the Left Guan position, it indicates blood failing to nourish the tendons. If encountered at the Right Guan position, it indicates Spleen deficiency with dampness invasion. If obtained at the Left Chi position, it indicates withered and damaged essence and blood. If obtained at the Right Chi position, it indicates failure of Mingmen fire and peril to life.

[Commentary] The name "Ru" implies "soft." It must be observed as fine and soft during the floating examination (light touch); it cannot be perceived during the middle or deep examinations. Wang Shuhe compared it to silk floating on water, and Li Shizhen compared it to bubbles floating on water; both descriptions metaphorically depict its image of disappearing upon touch. The *Mai Jing* states, "It is felt with light hands, but vanishes upon pressing," whereas the spurious prescription claims, "It seems present upon pressing, but disappears upon lifting." How contrary to truth this is! Moreover, if it seems present upon pressing but completely absent upon lifting, that is a Ruo (Weak) pulse, not a Ru pulse. The floating softness of the Ru pulse is similar to the Xu (Deficient) pulse; however, the Xu pulse has a large shape, while the Ru pulse has a small shape. The fineness and smallness of the Ru pulse are similar to the Ruo pulse; however, the Ruo pulse appears in the deep layer, while the Ru pulse appears in the floating layer. The rootlessness of the Ru pulse is similar to the San (Scattered) pulse; however, the San pulse gradually goes from floating and large to deep and absent, while the Ru pulse gradually goes from floating and small to completely invisible. From large to non-existent is an image of total misfortune; from small to non-existent is an image of half fortune and half misfortune.

Floating pulses govern the Qi aspect; they are obtainable by lifting, indicating that Qi has not yet failed. Deep pulses govern the Blood aspect; they are completely absent upon pressing, indicating that Blood has already been injured. In cases of chronic illness or in the elderly, seeing this pulse does not necessarily imply immediate death, because the pulse matches the symptoms. However, if seen in healthy individuals, the young and vigorous, or in acute sudden illnesses, it is called a pulse without roots, and death is near.

[Body and Image] The Ruo (Weak) pulse is fine and small, appearing in the deep layer; it is absent upon lifting, but obtained upon pressing.

[Main Pathology] The Ruo pulse indicates sinking of Yang and weakness of true Qi. At the Left Cun, it indicates Heart deficiency, with palpitations and forgetfulness. At the Right Cun, it indicates Lung deficiency, with spontaneous sweating and shortness of breath. At the Left Guan, it indicates desiccation of Liver Wood, inevitably suffering from tendon cramping and urgency. At the Right Guan, it indicates cold Earth [Spleen], leading to impaired digestion of water and grain. At the Left Chi, the weak form indicates that dried-up streams [Kidney Yin/Essence] can be verified. If seen at the Right Chi, it verifies the sinking of Yang.

[Commentary] The meaning of the Ruo pulse is a deep, fine, and small condition. Wang Shuhe in the *Mai Jing* said: "The Ruo pulse is extremely soft and deep-fine, obtained only upon pressing, and absent upon lifting." How clear and detailed this is! The spurious prescription borrows Wang Shuhe's name to deceive the world, claiming instead that the Ruo pulse is felt with light hands; this directly contradicts Wang Shuhe. Furthermore, this describes the shape of the Ru pulse, not the image of the Ruo pulse. Thus, we know that Gao Yangsheng mistakenly identified the Ru pulse as the Ruo pulse, and the Ruo pulse as the Ru pulse. It is surprising that authors who establish doctrines fail to conduct such basic verification! Even Li's metaphor of floating bubbles mistakenly identifies the Ru pulse as the Ruo pulse. Floating is used to examine Yang, and Yang governs the Qi aspect; if floating touch yields nothing, then Yang Qi is severely diminished, which is solid evidence. Yang Qi is what protects the exterior and consolidates the body, and also circulates through the Triple Burner and ripens food and drink. When the Ruo pulse presents, Yin-Cold is extreme; unless there is a sign of Stomach Qi, how can Yang recover? The *Su Wen* states: "A pulse that is weak and slippery indicates the presence of Stomach Qi. A pulse that is weak and choppy indicates a chronic illness." I believe that since the Ruo pulse can be pressed heavily, Yin has not yet perished; however, if accompanied by a choppy quality, it indicates mutual failure of Qi and Blood, and extinction of physiological life. Zhang Zhongjing said: "When Yang sinks into Yin, there should be aversion to cold and fever. Seen in chronic illness and old age, it can still be supported and rescued. Obtained in new illness and youth, death is inevitable." Liu stated: "Qi deficiency leads to a weak pulse. Weakness at Cun indicates Yang deficiency, weakness at Chi indicates Yin deficiency, and weakness at Guan indicates Spleen/Stomach deficiency."