或有难予者曰∶脉有七表、八里、九道,而无弦、钩、毛、石,书何谓春弦、夏钩、秋毛、冬石也
,且其义安在?予曰∶此阴阳升降之理也,三才原一太极。春弦者,肝之脉也,与胆为表里。夫阳气自
地而升,此时其气尚微,在半表半里之间,故其气来软弱,轻虚而滑,端直以长,故曰弦。夏脉钩者,
是阳极而阴生也。夫钩本大而末小,夏至一阴生,夏月六阳之气尽升,其脉来大而去小,故曰钩。秋脉毛
者,此毛字读
作毫字,《孟子》“明足以察秋毫之末”、正是此义。明阴气自天而降,轻细以浮,故曰毛。冬脉石
者,冬令万物潜藏之时,是阴极而阳生也。肾主其令,肾属水,主闭藏,沉而有力,如石之在水中,
故曰石。夫升降浮沉之理,变化无穷,岂凿凿之七表八里九道能悉耶!且脾胃平和之脉,不大不小,
不短不长,难以明状,惟以意消息之。彼二十四歌者,正如以管窥天也,噫!
或问生生子曰∶伤寒书桂枝汤后有云∶脉浮紧,发热汗不出者,不可与也,与之则表益实,而汗益
难出耳,则是以桂枝为固表药也,何麻黄汤中又用桂枝为臣耶?生生子曰∶考方疗疾,全在体认气味。《
衍义》谓桂大热,桂味辛甘,主温中,利肝肺气,为诸药先聘通使,温和荣卫,宣导百药,无所畏。然桂
枝汤用桂者,以其卫为邪袭,则气不固,故汗出恶风,桂枝味辛甘,阳剂也,阳剂其行快,入咽则先布
散,充达百骸四肢,无处不至,此散之之意也。至于止汗,自是芍药,芍药味酸,阴剂也,阴剂入咽,其
行迟,故先散之而后收之,一开一合,邪气散而真气不过泄,以
致于适中,非谓桂枝能止汗也。麻黄汤用桂枝为臣,亦以其辛甘发散为阳,若谓其实表止汗,将安用
之?盖以其寒伤荣,桂枝(能佐麻黄而散寒邪)温和荣卫,则邪自不能容留,汗出而解也。桂枝汤后叮
咛不可与者,为内有芍药,寒既伤荣,发热无汗,复用酸寒收敛之剂,则邪无从而出,表乃益实也,
非谓辛散能实表也。风,阳气也,阳主散,风伤卫,则气散而汗出。寒,阴气也,寒主敛,寒伤荣,则
气敛而无汗。故治法,无汗要有汗,取辛散能发汗也;有汗要无汗,取酸收能止汗也。俱用桂枝者,
以其既能发散,而又能温和荣卫也。予故曰∶考方疗疾,全在体认气味。
Someone questioned me, saying: Pulse diagnosis is categorized into Seven Exterior (Qi Biao), Eight Interior (Ba Li), and Nine Channels (Jiu Dao), yet there is no mention of Wiry (Xian), Hooked (Gou), Hairy (Mao), or Stony (Shi) pulses. Why do medical texts state that the spring pulse is Wiry, summer is Hooked, autumn is Hairy, and winter is Stony? Moreover, what is the rationale behind this? I replied: This concerns the principle of the ascending and descending of Yin and Yang; Heaven, Earth, and Humanity (San Cai) all originate from the Supreme Ultimate (Taiji). The spring pulse being Wiry refers to the Liver pulse, which is interiorly-exteriorly related to the Gallbladder. Yang Qi ascends from the earth; at this time, its energy is still subtle, residing between the exterior and interior. Therefore, the qi comes forth soft and weak, light and void, smooth, straight, and long, hence it is called "Wiry." The summer pulse being Hooked signifies the peak of Yang and the birth of Yin. The character "Hook" originally denotes a shape that is large at the head and small at the tail. At the Summer Solstice, Yin is born. During summer, the six Yang energies fully ascend; the pulse arrives strongly but departs weakly, hence it is called "Hooked." The autumn pulse being Hairy: the character "Mao" is pronounced as "Hao." As stated in *Mencius*, "Vision sufficient to see the tip of an autumn hair," precisely conveys this meaning. It indicates that Yin Qi descends from heaven, being light, fine, and floating, hence it is called "Hairy." The winter pulse being Stony occurs when all things hibernate in winter, representing the peak of Yin and the birth of Yang. The Kidney governs this season; the Kidney belongs to Water and governs storage. The pulse is deep and forceful, like a stone submerged in water, hence it is called "Stony." The principles of ascending, descending, floating, and sinking are infinitely variable; how could the rigid categories of Seven Exterior, Eight Interior, and Nine Channels fully encompass them! Furthermore, the pulse of harmonious Spleen and Stomach is neither large nor small, neither short nor long, difficult to describe explicitly, and can only be appreciated through intuitive contemplation. Those songs describing twenty-four pulse types are like looking at the sky through a tube (having a narrow perspective), alas!
Someone asked Shengshengzi (Sun Yikui's pseudonym): In texts treating Cold Damage (Shanghan), following the description of Guizhi Tang (Cinnamon Twig Decoction), it states: "If the pulse is floating and tight, with fever but no sweating, Guizhi Tang should not be administered; if given, the exterior will become more solidified, and sweating will become even more difficult." This seems to imply that Guizhi (Cinnamon Twig) is a medicine for consolidating the exterior. Why, then, is Guizhi used as a Deputy Minister (Chen) herb in Mahuang Tang (Ephedra Decoction)? Shengshengzi replied: Examining formulas to treat diseases relies entirely on the experiential understanding of medicinal properties and flavors (Qi Wei). *Yanyi* states that Cinnamon is greatly hot; its flavor is pungent and sweet, primarily warming the middle, benefiting Liver and Lung Qi, acting as a pioneer and guide for other herbs, gently harmonizing Ying and Wei (Nutritive and Defensive levels), and facilitating the action of various medicines without fear. Regarding the use of Cinnamon in Guizhi Tang: because the Defensive Qi has been attacked by pathogenic factors, leading to insecure Qi and thus sweating and aversion to wind, Cinnamon, with its pungent and sweet flavor, is a Yang agent. Yang agents act swiftly; upon ingestion, they disperse first, filling and reaching the hundred vessels and four limbs, penetrating everywhere. This represents the intention of dispersing. As for stopping sweating, this is the function of Shaoyao (Peony Root). Shaoyao has a sour flavor and is a Yin agent. Yin agents act slowly upon ingestion; thus, the formula first disperses and then collects/astringes. One opens, one closes; the pathogenic factor dissipates while the True Qi does not leak excessively, achieving a balanced state. It is not said that Cinnamon stops sweating. In Mahuang Tang, Cinnamon is used as a Deputy Minister also because its pungent and sweet dispersing nature is Yang. If it were believed to consolidate the exterior and stop sweating, what would be its purpose? It is likely because Cold damages the Nutritive level; Cinnamon assists Mahuang (Ephedra) to scatter Cold pathogens and gently harmonize Ying and Wei, so that pathogens cannot remain, and the disease resolves through sweating. The warning after Guizhi Tang regarding non-administration is due to the presence of Shaoyao in the formula. Since Cold has already damaged the Nutritive level, if there is fever and no sweating, using another sour-cold astringent agent would leave no exit for the pathogen, causing the exterior to become even more solidified. This is not to say that Pungent-Dispersing agents solidify the exterior. Wind is Yang Qi; Yang governs dispersion. When Wind damages the Defensive level, Qi scatters, resulting in sweating. Cold is Yin Qi; Yin governs consolidation. When Cold damages the Nutritive level, Qi contracts, resulting in no sweating. Therefore, treatment methods dictate: for no sweating, induce sweating to achieve sweating, utilizing Pungent-Dispersing properties; for existing sweating, stop sweating to achieve no sweating, utilizing Sour-Astringent properties. Both utilize Cinnamon because it can both disperse and gently harmonize Ying and Wei. Thus, I say: Examining formulas to treat diseases relies entirely on the experiential understanding of medicinal properties and flavors.