痈疽不论上中下，惟在阴阳二症推，发背虽有正与偏，要取高低两样看。纯阳初起必 肿，更兼身热有微
寒，顶如尖字高突起，肿似弯弓根有盘。七日之间多 痛，二七之间脓渐漫，动息自宁食知味，二便调匀无泻
干。肿消脓溃精神爽，脱腐生新气血完，五善自然臻并至，七恶全无半点干。痛便随脓减，肿退自肌宽；新肉
已生红艳艳，腐皮自敛白漫漫，一身多爽快，五脏尽和欢。此属纯阳俱易治，百人百可保全安。
纯阴初起不知疮，粟米之形疙瘩僵，不红不肿不知痛，少热少 少提防。七朝之后身体倦，疮根平大喜浇
汤，顶不高兮根不活，色不光兮腐不穣。陷软无脓空结聚，脉浮散大细飞扬，饮食不餐身战战，尝汤止许意忙
忙。疮上生衣如脱甲，孔中结子似含芳，脓多臭秽身难便，举动怆惶韵不长。疮形成紫黑，面色变青黄；精神
昏愦多鼾睡，言语无人自发扬，口干多舌强，痰喘定身亡。此属纯阴俱不治，百人百可到泉乡。
阴阳之症两相交，生死同兼事可招，微热微寒微赤肿，半昏半爽半平高。脉来虽数多无力，饮食虽餐便不
消，肿而不溃
因脾弱，溃而不敛为脓饶。大便多溏小便数，上身有汗下体焦。五善虽兼有，七恶未全逃；口渴喜茶肠腹痛，
面浮餍饮足心高。心烦不稳睡，神乱怕音焦；投方应病方为妙，阴转为阳渐可调。心真造化，尔命坚牢，逢之
任是神仙手，半死余生定莫逃。
痈疽（体表化脓性感染）不论发生在身体上部、中部还是下部，关键在于辨别其属于阳证还是阴证。发背（背部痈疽）虽然有正中和偏侧之分，但也要根据病灶的高低形态来分别观察。
纯阳证初起时必然出现红肿，同时伴有身体发热和轻微恶寒，疮顶像“尖”字一样高高突起，肿胀形状像弯弓，根部有盘状基底。发病七天内疼痛剧烈，十四天左右脓液逐渐漫溢，此时患者呼吸平稳，食欲恢复，大小便调匀，没有腹泻或干燥便秘的情况。随着肿胀消退、脓液溃破，精神变得清爽，腐肉脱落、新肉生长，气血得以完善。“五善”（五种预后良好的征象）自然全部到来，“七恶”（七种预后不良的征象）完全没有沾染。疼痛随着脓液排出而减轻，肿胀退去后肌肉自然舒展；新生的肉芽红艳鲜艳，坏死的皮肤自行收敛变白，全身感觉爽快，五脏功能调和欢畅。这属于纯阳证，都容易治疗，百人之中几乎都能保全性命平安。
纯阴证初起时看不出明显的疮形，像粟米大小的疙瘩僵硬不动，不红不肿也不觉得疼痛，只有轻微的发热和微寒需要小心提防。七天之后身体疲倦，疮根平坦，喜欢喝冷饮，疮顶不高，根基不活，色泽不光亮，腐肉不熟烂。疮面塌陷柔软，没有脓液，只是空虚结聚，脉象浮散大且细弱飞扬，不想饮食，身体颤抖，喝汤水时只敢心里着急却不敢多喝。疮面上生长的肉衣像脱落的指甲，孔中结成的硬块像含苞待放的花蕾，脓液多且臭秽，身体难以受用，举动惊慌失措，气息短促。疮形呈现紫黑色，面色变为青黄色；精神昏沉困倦，多鼾睡，言语无人应答却自言自语，口干舌强，痰喘最终导致死亡。这属于纯阴证，都难以治愈，百人之中几乎都会走向死亡。
阴阳两种证候相互交错，生死吉凶兼而有之，情况复杂。表现为微热、微寒、微赤肿，神志半昏半爽，疮势半平半高。脉象虽然快但大多无力，虽然能进食但大便不消化，肿胀但不溃破是因为脾气虚弱，溃破后不收敛是因为脓液过多。大便多稀溏，小便频数，上身出汗而下身焦躁。虽然兼有“五善”，但“七恶”也未完全逃脱；口渴喜欢喝茶，肠腹痛，面部浮肿，厌食饮水，足心高突。心烦意乱无法安稳睡觉，神志错乱害怕声音焦躁。投用的方药必须对症才算巧妙，使阴证转为阳证，病情逐渐可调治。若是医者具有真正的造化之功，患者的生命就能坚固牢靠；遇到这种情况，即使是神仙之手，对于半死余生者也可能无法挽救。
Carbuncles and sores (superficial suppurative infections), regardless of whether they occur in the upper, middle, or lower parts of the body, depend primarily on distinguishing between Yang syndromes and Yin syndromes. For back carbuncles (carbuncle on the back), although there are central and lateral variations, one must also observe them according to their high and low morphological characteristics.
In a pure Yang syndrome, initial onset is characterized by definite swelling, accompanied by fever and slight aversion to cold. The apex rises sharply like the character "Jian" (pointed), the swelling resembles a curved bow, and the base has a discoid spread. Within seven days, pain is severe; within fourteen days, pus gradually spreads. At this stage, breathing becomes calm, appetite returns, and bowel and bladder functions are regular without diarrhea or dryness. As swelling subsides and pus erupts, spirit refreshes, necrotic tissue sloughs off, new flesh grows, and Qi and Blood are restored. The "Five Good Signs" (five prognostic indicators of favorable outcome) naturally arrive completely, while the "Seven Bad Signs" (seven prognostic indicators of unfavorable outcome) are entirely absent. Pain decreases with pus discharge, and swelling recedes allowing muscles to relax; newly formed granulation tissue appears bright red, while necrotic skin retracts and turns white. The whole body feels comfortable, and the five Zang organs function harmoniously. This belongs to pure Yang syndrome, which is easy to treat; nearly all patients can be saved and remain safe.
In a pure Yin syndrome, the initial onset shows no distinct sore shape, appearing as stiff nodules the size of millet grains. There is no redness, no swelling, and no pain, requiring caution for slight fever and slight aversion to cold. After seven days, the body feels fatigued, the sore base is flat, and the patient desires cold drinks. The apex is not elevated, the base is inactive, the color is dull, and the necrotic tissue is not ripe. The lesion is depressed and soft with no pus, only empty aggregation. The pulse is floating, scattered, large, yet fine and flying. There is loss of appetite, trembling of the body, and anxiety when drinking fluids. The tissue growing on the sore resembles shed nails, and hard knots inside the pores resemble budding flowers. Pus is abundant and foul-smelling, causing bodily discomfort. Movements are panicked, and respiration is short. The sore takes on a purple-black color, and the complexion turns greenish-yellow. Spirit is confused and drowsy with snoring; speech is disjointed, speaking to no one. There is dry mouth, tongue stiffness, phlegm, and wheezing, ultimately leading to death. This belongs to pure Yin syndrome, which is untreatable; nearly all patients will perish.
When Yin and Yang syndromes intersect, life and death outcomes are mixed, presenting complex situations. Symptoms include slight fever, slight aversion to cold, slight redness and swelling, half-confused and half-clear consciousness, and a sore that is partially flat and partially elevated. The pulse may be rapid but mostly forceless. Although food is consumed, digestion is poor. Swelling without ulceration indicates Spleen deficiency; ulceration without healing indicates excessive pus. Frequent loose stools and frequent urination occur, with sweating on the upper body and dryness/irritability in the lower body. Although some "Five Good Signs" are present, the "Seven Bad Signs" have not been fully escaped. Thirst with a preference for tea, abdominal pain, facial edema, anorexia, and elevation of the sole of the foot are observed. Restlessness prevents sound sleep; mental confusion causes fear of noise. Prescriptions must match the disease precisely to be effective, transforming Yin into Yang so the condition gradually becomes manageable. If the physician possesses true creative power, the patient's life can be secured. However, even if met with the hands of an immortal, those in a state of half-death and half-life may still escape salvation.