问曰∶头汗何以是半表半里证？答曰∶诸阳经上至于头，则有头汗，若诸阴经，皆至颈
而还，则头无汗，故见头汗出，即半表半里证。又问曰∶诸阳脉上至于头，今头汗出，当是
表证，何以为半表半里也？答曰∶若是表证，尚有寒邪闭塞，焉得有汗？今既有汗，是寒邪将
化为热也。但名曰里证，则头与身皆出汗，但名曰表证，则头无汗，故曰半表半里也。又问
曰∶瘀血、发黄、水气，皆有头汗出，何也？答曰∶瘀血头汗出，小便自利，小腹满痛，大
便黑色；发黄头汗出，小便不利，目珠黄；水气头汗出，胸胁痞满，咳引胁下痛。若少阳证
头汗出，必见往来寒热诸证，以此为别。
问曰∶盗汗何以是半表半里证？答曰∶热邪熏灼，腠理开，令人自汗，寒则腠理闭塞而
无汗。今汗睡而出，觉而收，是邪将盛于阴，而未深入于阴，故曰半表半里也。又问曰∶杂
症盗汗，何也？答曰∶杂症盗汗，乃阴虚之证。伤寒盗汗，乃外感之邪，自不同类。
问曰∶舌苔滑，何以是半表半里证？答曰∶舌司肠胃寒热之变，在表则津液如常，在里
则胎燥黄黑。今舌苔滑，尚有津液，但不如常，是邪将入腑，而未深入于腑也。既不在表，
亦不在里，故曰半表半里证。
问曰∶脉弦，何以是半表半里证？答曰∶弦者，肝之本脉也。肝胆相为表里，且胆为乙
木，木主风，于时为春，故脉弦也。太阳脉浮，阳明脉长，少阳脉弦，此三阳诊候之法也。
Q: Why is head sweating (tou han) considered a Shaoyang syndrome (half-exterior, half-interior syndrome)? A: All Yang meridians ascend to the head, hence head sweating occurs; whereas all Yin meridians only reach the neck and return, so there is no sweat on the head. Therefore, the presence of head sweating indicates a Shaoyang syndrome. Further question: Since all Yang pulses ascend to the head, and now there is head sweating, should it not be an exterior syndrome? Why is it called half-exterior, half-interior? Answer: If it were an exterior syndrome, cold pathogen would obstruct the pores, how could there be sweat? The fact that there is sweat now indicates that the cold pathogen is transforming into heat. If it were termed an interior syndrome, both the head and body would sweat; if it were termed an exterior syndrome, the head would not sweat. Hence, it is called half-exterior, half-interior. Further question: Blood stasis (Yu Xue), jaundice (Fa Huang), and fluid retention (Shui Qi) all present with head sweating. Why is this? Answer: In cases of blood stasis causing head sweating, urination is free, the lower abdomen is full and painful, and stools are black; in cases of jaundice causing head sweating, urination is difficult, and the sclerae are yellow; in cases of fluid retention causing head sweating, there is chest and hypochondriac stuffiness and fullness, and coughing draws pain from the hypochondrium. If it is a Shaoyang syndrome causing head sweating, it must be accompanied by alternating chills and fever and other symptoms, which serves as the distinction.
Q: Why is night sweating (dao han) considered a Shaoyang syndrome? A: Heat pathogen steams and scorches, opening the cou-li (pores and interstices), leading to spontaneous sweating; cold causes the cou-li to close, resulting in no sweat. Now, sweating occurs during sleep and stops upon waking. This indicates that the pathogen is about to flourish in the Yin aspect but has not yet deeply penetrated the Yin. Hence, it is called half-exterior, half-interior. Further question: What about night sweating in miscellaneous diseases? Answer: Night sweating in miscellaneous diseases belongs to Yin deficiency syndromes. Night sweating in Shanghan (Cold Damage) is caused by exogenous pathogens; they are of different categories.
Q: Why is a slippery tongue coating (she tai hua) considered a Shaoyang syndrome? A: The tongue reflects changes in cold and heat in the stomach and intestines. In exterior syndromes, body fluids are normal; in interior syndromes, the tongue coating is dry, yellow, or black. Now, the tongue coating is slippery, indicating the presence of body fluids, though not entirely normal. This suggests the pathogen is about to enter the Fu organs but has not yet deeply penetrated them. Since it is neither in the exterior nor in the interior, it is called a Shaoyang syndrome.
Q: Why is a wiry pulse (mai xian) considered a Shaoyang syndrome? A: The wiry pulse is the native pulse of the Liver. The Liver and Gallbladder are exterior-interiorly related. The Gallbladder belongs to Yi Wood; Wood governs Wind and corresponds to the season of Spring; therefore, the pulse is wiry. The Taiyang pulse is floating (Fu), the Yangming pulse is long (Chang), and the Shaoyang pulse is wiry (Xian). These are the diagnostic methods for the three Yang meridians.