窃闻爪之生。发之长。营卫之行。无顷刻止。且爪者。筋之余。胆之外候也。灵枢曰。胆应爪。爪浓色黄者胆浓。
爪薄色红者胆薄。爪坚色青者胆急。爪濡色赤者胆缓。爪直色白无约者胆直。爪恶色黑多纹者胆结。盖
胆者肝之腑。爪者肝之华。故以爪候胆也。然候胆者言其常。而诊病者论其变也。其变维何。爪甲青者多
凶。爪甲赤者多热。爪甲黄者疸病。爪甲白者寒证。爪甲黑者。或因血瘀而痛。或因血凝而死。要之润则吉。
枯则凶。爪色虽殊。其变皆决于此矣。诸书谓痹病骨痛爪枯者。足少阳血气皆少。色苍爪枯者肝热。爪甲
黑。干呕面青。肢厥冷者病凶。病患爪甲白者不治。爪甲青者死。爪甲下肉黑者。八日死。手足爪甲青。呼骂
不休者筋绝。九日死。小儿爪甲青黑。忽作鸦声者肝绝。小儿咬爪甲者。乳少成疳。心病为疟。心烦甚。欲得
清水。反寒多热不甚。若其人本来心性和雅。今忽弊急。言未竟便住。以手剔脚爪。此人心死。名曰行尸。是
皆诊爪之目也。能参合而行之。庶无虚虚实实之弊矣。
诊乳之法。内经未言。李梃医学入门云。女人属阴。阴极则必自下而上冲。故乳房大而阴户缩也。男子属
阳。阳极则必自上而下降。故阴茎垂而乳头缩也。杨士瀛曰。男子以肾为重。妇人以乳为重。上下不同。而
性命之根则一。诊乳之法。观此亦可心解矣。何也。相书谓妇人乳头朝上。生子易养。乳头朝下。生子难养。
以脾胃冲任之有强弱也。乳大者子多。乳小者子少。以脾胃冲任之有盛衰也。白小低偏者。子息难。以形
色亏也。黑大坚硬者。子息好。以形色全也。男胎则左乳先胀硬。女胎则右乳先胀硬。阳从左。阴从右也。妇
人受孕。其乳当转黑。小儿脐风。其乳当结核。有诸中。形诸外也。至于妇人乳中坚硬。不红不痛者。乳岩也。
乳中肿胀。色红且痛者。乳痈也。痈者壅也。疽者阻也。六腑有所壅。则为痈。五脏有所阻。则为岩也。合色脉
而察之。亦诊妇人赤子之一助云尔。
I have heard that the growth of nails and hair, as well as the circulation of Ying (Nutrient) Qi and Wei (Defensive) Qi, never ceases for a moment. Moreover, nails are the surplus of tendons and serve as an external manifestation of the Gallbladder. The *Ling Shu* states: "The Gallbladder corresponds to the nails." Thick nails with yellow color indicate a thick Gallbladder; thin nails with red color indicate a thin Gallbladder; hard nails with cyan color indicate urgent Gallbladder Qi; soft and moist nails with crimson color indicate relaxed Gallbladder Qi; straight nails with white color and no constraint indicate upright Gallbladder Qi; malformed nails with black color and many lines indicate knotted Gallbladder Qi. Since the Gallbladder is the interiorly-exteriorly related organ of the Liver, and nails are the floral manifestation of the Liver, we observe the Gallbladder through the nails. However, observing the normal state of the Gallbladder refers to the constant, while diagnosing disease discusses the variable. What are these variables? Cyan nails often indicate ominous signs; red nails often indicate Heat syndromes; yellow nails indicate Jaundice disease; white nails indicate Cold syndromes; black nails may be due to Blood stasis causing pain or Blood coagulation leading to death. In summary, moistness indicates auspiciousness, while dryness indicates ominousness. Although nail colors vary, their diagnostic judgments all derive from this principle. Various texts state that in Bi syndrome with bone pain and dry nails, there is a deficiency of Qi and Blood in the Foot Shaoyang channel; dark complexion with dry nails indicates Liver Heat; black nails accompanied by dry heaving, cyan face, and cold limbs indicate a critical condition; patients with white nails are incurable; cyan nails indicate death; black flesh under the nails indicate death within eight days; cyan nails on hands and feet with incessant shouting and cursing indicate tendon exhaustion, with death within nine days; cyan-black nails in infants with sudden crow-like sounds indicate Liver exhaustion; infants biting their nails indicate Gan accumulation disease caused by insufficient breast milk; Heart disease manifests as malaria, with severe restlessness, desire for cold water, but more chills than fever. If a person who was originally calm and elegant suddenly becomes irritable, stops speaking abruptly, and picks at toenails, this indicates the death of the Heart spirit, termed "Walking Corpse." These are all the items in nail diagnosis. By integrating and applying these methods, one can avoid the error of treating deficiency as excess and excess as deficiency.
The method of examining breasts is not mentioned in the *Nei Jing*. Li Ting in *Yixue Rumen* states: Women belong to Yin; when Yin reaches its extreme, it must surge upward from below, hence large breasts and contracted vulva; Men belong to Yang; when Yang reaches its extreme, it must descend downward from above, hence hanging penis and retracted nipples. Yang Shiyin said: For men, the Kidney is paramount; for women, the breast is paramount. Though upper and lower differ, the root of life remains one. The method of examining breasts can be understood from this. Why? Physiognomy books state that if a woman's nipples point upward, her children are easy to raise; if they point downward, her children are difficult to raise, due to the strength or weakness of the Spleen, Stomach, Chong, and Ren vessels. Large breasts indicate many children, small breasts indicate few children, due to the prosperity or decline of the Spleen, Stomach, Chong, and Ren vessels. White, small, low, and deviated breasts indicate difficulty in offspring due to deficient form and color; black, large, and hard breasts indicate good offspring due to complete form and color. A male fetus causes the left breast to swell and harden first; a female fetus causes the right breast to swell and harden first, because Yang follows the left and Yin follows the right. Upon pregnancy, a woman's breasts should turn black; in infant umbilical tetanus, the breasts should develop nodules. Internal changes manifest externally. As for hardness in a woman's breast without redness or pain, it is Ru Yan (Breast Cancer); swelling with redness and pain is Ru Yong (Mastitis). "Yong" means obstruction; "Ju" means blockage. Obstruction in the Six Fu organs leads to Yong; blockage in the Five Zang organs leads to Yan (malignant tumor). Observing both color and pulse aids in diagnosing conditions in women and infants.