痘有顺逆险三者，治痘不可不知也。顺者，吉之象也。逆者，凶之象也。险者，悔
吝之象也。吉则不必治，治则反凶，凶不劳治，治则何益？至于险者，则宜治矣。夫痘
之不齐，由气血之不均也。夫气血充盛，则毒易解而为顺矣。此不治而自痊者也。如气
血损，则毒难愈而为逆矣，此即虽治而无益者也。惟气血少弱，其毒不能顿解，而生意
不固乎中，故必加以补益扶持之功耳。所谓得助者昌，失助者亡，且痘疏而毒少者，则
邪不胜正，其气自和，其势自顺，不须服药。若痘密而毒多者，则邪正相持，其气乃
病，其势乃险，此宜抑邪扶正，使邪气亟夺，而不为正气之贼。若痘稠密无偏而毒甚
者，则正不胜邪，其气自乖，其势自逆，即虽善治者，束手待毙而已。故顺者勿治，险
者贵治，逆者不治，其理于此可见矣。
痘有五善七恶，治者宜熟谙也。何谓五善，一饮食如常，二大小便调，三色泽红活
坚实，四脉静身凉，手足和缓，五声音响亮，动止安宁。五者，不能毕具，若得二
三，自然清吉。其七恶者何？烦燥闷乱，谵妄恍惚，一也。呕哕泄泻，不能饮食，二
也。青干黑陷，痒塌破烂，三也。头面预肿，鼻塞目闭唇裂，四也。寒战切牙，声哑
色黯，五也。喉舌溃烂，食入则呕，饮水则呛，六也。腹胀喘促，四肢逆冷，七也。七
恶之中，但见一症，即势不可为，七恶之外，复有浑身血泡，心腹刺痛，伏陷不出，
斑疔肉硬，便溺皆血，寻衣捏空，是又速亡之候也。
痘疹有顺证、逆证、险证三种情况，治疗痘疹不可不明了。顺证，是吉祥的征象。逆证，是凶险的征象。险证，是令人悔恨与困难的征象。若是吉（顺）证则不必治疗，若强行治疗反而会导致凶险；若是凶（逆）证则无需劳神治疗，治疗又有什么益处呢？至于险证，则是适宜治疗的。
痘疹出得参差不齐，是由于气血分布不均所致。如果气血充盛，则毒邪容易化解而表现为顺证，这是不治疗也能自愈的情况。如果气血亏损，则毒邪难以痊愈而表现为逆证，这就是即使治疗也无益处的情况。只有气血稍显虚弱，毒邪不能立刻解除，且生机在中焦不够稳固，所以必须加以补益扶持的功夫。所谓得到辅助则昌盛，失去辅助则灭亡。而且痘疹稀疏、毒邪少的，则邪气不胜正气，其气机自然调和，其病势自然顺遂，不需要服药。如果痘疹稠密、毒邪多的，则邪正双方相持不下，其气机处于病态，其病势处于危险状态，这时适宜抑制邪气、扶助正气，使邪气迅速被剥夺，而不成为正气的贼害。如果痘疹稠密均匀但毒邪极重的，则正气不胜邪气，其气机自然乖乱，其病势自然逆乱，即使是善于治疗的大夫，也只能束手待毙罢了。所以顺证不要治疗，险证贵在及时治疗，逆证不予治疗，其中的道理从这里就可以看清楚了。
痘疹有五善七恶，治疗者应当熟悉掌握。什么是五善？第一，饮食如常；第二，大小便调畅；第三，痘色红活、坚实；第四，脉象平静、身体凉爽、手足和缓；第五，声音响亮、动静安宁。这五种表现，不可能全部具备，如果能具备两三种，自然就会清吉平安。那七恶是什么呢？烦躁闷乱、胡言乱语、精神恍惚，这是一恶。呕吐呃逆、泄泻、不能进食，这是二恶。痘色青紫干枯、黑陷、瘙痒塌陷、破烂，这是三恶。头面部预先肿胀、鼻塞、眼睛闭合、嘴唇干裂，这是四恶。寒战咬牙、声音嘶哑、面色晦暗，这是五恶。咽喉舌头溃烂、吃东西就呕吐、喝水就呛咳，这是六恶。腹部胀满、气喘急促、四肢厥冷，这是七恶。在七恶之中，只要见到一种症状，病情就不可挽回了。在七恶之外，又有浑身血泡、心腹刺痛、痘毒伏陷不出、斑疔肉质坚硬、大小便出血、寻衣摸空（无意识动作），这些又是迅速死亡的征兆。
Smallpox (or variola) presents in three patterns: Shun (Smooth/Favorable), Ni (Rebellious/Unfavorable), and Xian (Dangerous). Practitioners must understand these. Shun represents a favorable omen. Ni represents an ominous omen. Xian represents an omen of regret and difficulty. If the pattern is Favorable, treatment is unnecessary; intervening may lead to unfavorable outcomes. If the pattern is Unfavorable, laboring with treatment is futile; what benefit would it bring? However, for Dangerous patterns, treatment is indicated.
The uneven eruption of lesions arises from the uneven distribution of Qi and Blood. When Qi and Blood are abundant, toxins are easily resolved, manifesting as a Smooth pattern; this heals spontaneously without treatment. If Qi and Blood are deficient, toxins are difficult to resolve, manifesting as an Unfavorable pattern; here, even treatment yields no benefit. Only when Qi and Blood are slightly weak, such that toxins cannot be instantly cleared and the vital energy in the Middle Jiao is not firmly established, is it necessary to apply tonifying and supporting methods. As the saying goes, "Assistance leads to prosperity; lack of assistance leads to demise." Furthermore, if lesions are sparse and toxin load is low, pathogenic factors cannot overcome healthy Qi; the Qi mechanism harmonizes naturally, and the disease course proceeds smoothly, requiring no medication. If lesions are dense and toxin load is high, pathogenic factors and healthy Qi contend equally; the Qi mechanism becomes pathological, and the disease course becomes dangerous. In such cases, it is appropriate to suppress pathogens and support healthy Qi, rapidly depriving the pathogen of its hold so it does not become a thief to healthy Qi. If lesions are densely uniform but the toxin burden is extreme, healthy Qi cannot overcome pathogens; the Qi mechanism becomes disordered, and the disease course becomes rebellious. Even skilled practitioners can only wait helplessly for death. Thus, do not treat Smooth patterns; prioritize treating Dangerous patterns; do not treat Unfavorable patterns. The rationale is evident here.
There are Five Good Signs and Seven Bad Signs in smallpox; practitioners should be thoroughly familiar with them. What are the Five Good Signs? First, normal diet and appetite; second, regular bowel movements and urination; third, lesions are red, vibrant, firm, and solid; fourth, pulse is calm, body temperature is cool, and hands and feet are relaxed; fifth, voice is resonant, and movement/rest is peaceful. These five signs need not all be present simultaneously; if two or three are observed, recovery is naturally assured. What are the Seven Bad Signs? First, irritability, restlessness, delirium, and mental confusion. Second, vomiting, hiccups, diarrhea, and inability to eat. Third, lesions turning cyanotic, dry, black, sunken, pruritic, collapsed, or ulcerated. Fourth, premature swelling of the head and face, nasal congestion, closed eyes, and cracked lips. Fifth, chills, teeth grinding, hoarse voice, and dark complexion. Sixth, ulceration of the throat and tongue, vomiting upon eating, and choking upon drinking. Seventh, abdominal distension, panting, and cold extremities. Within the Seven Bad Signs, the appearance of any single symptom indicates an incurable condition. Beyond the Seven Bad Signs, if there are blood blisters over the whole body, stabbing pain in the heart and abdomen, lesions failing to erupt (sunken inward), hard nodules resembling thorns, hematuria and bloody stools, or picking at empty air (involuntary grasping movements), these are signs of rapid demise.