经言治其旺气者，谓病有阴阳，气有盛衰，旺则治之反甚。如阳盛阴衰者，阴虚火旺也
，治
之者，不知补阴以配阳，而专用苦寒治火之旺，岂知苦寒皆沉降，沉降则亡阴，阴愈亡则火
愈盛，故服寒反热者，阴虚不宜降也。又如阳衰阴盛者，气弱生寒也，治之者，不知补阳以
消阴，则寒愈甚，故服热反寒者，阳虚不宜耗也。又如夏令本热，而伏阴在内，故多中寒，
冬令本寒，而伏阳在内，故多内热。设不知此，而必欲用寒于夏，治火之旺；用热于冬，治
寒之旺；则有中寒隔阳者，服寒反热；中热隔寒者，服热反寒矣，是皆治旺之谓，而病之所
以反也。
夫阳常有余，阴常不足，在天地则该万物而言，在人身则该一体而言，非直指气为阳而
血为
阴也。经曰∶阳中有阴，阴中有阳，正所谓独阳不生，独阴不长也。姑以治法兼证论之曰∶
气虚者，气中之阴虚也，治法以四君子汤，补气中之阴；曰血虚者，血中之阴虚也，治法以
四物汤，补血中之阴；曰阳虚者，心经之元阳虚也，病多恶寒，责其无火，治法以补气药中
加桂，甚则三建中汤、正阳散之类；曰阴虚者，肾中之真阴虚也，病多壮热，责其无水，治
法以补血药中加知柏等药，或大补阴丸、滋阴地黄丸之类。夫真元极衰之候，初不可服桂、
附等药，恐反助火而烁真阴。元阳虚脱之躯，亦不可投芎、苓等辛散淡渗之剂，恐反开腠理
而泄其气。昧者谓气虚即阳虚，止宜用四君，断不可服芎、苓之属。血虚即阴虚，止宜用四
物，切不可用参、 之属。殊不知血脱补气，昔贤之治法也。惟真阴虚极，将为劳蒸咳嗽，
必用参、 ，恐肺热伤肺，不能抵当，而反益其病，可勿泥也。
经文说治疗“旺气”，是指疾病有阴阳之分，正气有盛衰之别，如果气机旺盛时反而去攻治它，病情就会加重。例如阳盛阴衰的情况，属于阴虚火旺，治疗者如果不懂得通过补阴来制约阳亢，而专门使用苦寒药物来清泻火的亢盛，哪里知道苦寒药性多沉降，沉降则会导致阴液耗损，阴液越耗损火就越旺盛，所以服用寒凉药反而出现热象，这是因为阴虚证不宜用降法。再如阳衰阴盛的情况，属于气弱生寒，治疗者如果不懂得通过补阳来消散阴寒，那么寒气就会更重，所以服用温热药反而出现寒象，这是因为阳虚证不宜用耗散法。又如夏季本来炎热，但体内潜伏着阴寒之气，所以容易发生中寒证；冬季本来寒冷，但体内潜伏着阳热之气，所以容易发生内热证。假如不知道这些道理，一定要在夏天用寒凉药治疗火的亢盛，在冬天用温热药治疗寒的亢盛；那么对于中寒隔阳的患者，服用寒凉药反而会出现热象；对于中热隔寒的患者，服用温热药反而会出现寒象。这些都是所谓“治疗旺气”却导致病情反复的原因。
阳气常常有余，阴气常常不足，这在天地之间是涵盖万物的说法，在人体上则是涵盖整体而言的，并不是直接指气就是阳、血就是阴。经典说：阳中有阴，阴中有阳，这正是所谓的“独阳不生，独阴不长”。暂且从治法和兼证的角度来论述：气虚，指的是气中的阴虚，治法用四君子汤，以补益气中的阴；血虚，指的是血中的阴虚，治法用四物汤，以补充血中的阴；阳虚，指的是心经的元阳虚，病症多表现为怕冷，原因在于无火，治法是在补气药中加入桂枝，严重时可用三建中汤、正阳散之类；阴虚，指的是肾中的真阴虚，病症多表现为壮热，原因在于无水，治法是在补血药中加入知母、黄柏等药，或者大补阴丸、滋阴地黄丸之类。当真元极度衰弱的时候，起初不可服用桂枝、附子等药，恐怕反而助长火势而灼伤真阴。元阳虚脱的身体，也不可投用川芎、茯苓等辛散淡渗的药剂，恐怕反而打开腠理而泄耗正气。愚昧的人认为气虚就是阳虚，只适宜用四君子汤，绝对不可服用川芎、茯苓之类的药。血虚就是阴虚，只适宜用四物汤，切不可用人参、麦冬之类的药。却不知道“血脱补气”是古代贤人的治法。只有当真阴极度虚弱，即将出现劳蒸咳嗽时，必须用人参、麦冬，恐怕肺热损伤肺脏，无法抵挡，从而反而加重病情，这一点不要拘泥。
The classic states that treating the "prosperous qi" refers to the fact that diseases have yin and yang aspects, and qi has excess and deficiency. If one treats against the prosperous qi when it is abundant, the condition will worsen. For instance, in cases of Yang excess and Yin deficiency, which is characterized by Yin deficiency with hyperactive fire, if the practitioner does not understand how to tonify Yin to harmonize with Yang, but instead exclusively uses bitter-cold herbs to clear the hyperactive fire, they fail to realize that bitter-cold substances are generally descending in nature. Descending actions lead to the depletion of Yin fluids; as Yin depletes further, fire becomes even more vigorous. Therefore, taking cold medicines may result in heat symptoms, indicating that Yin deficiency should not be treated with descending methods. Similarly, in cases of Yang deficiency and Yin abundance, which is characterized by Qi weakness generating cold, if the practitioner does not understand how to tonify Yang to dissipate Yin cold, the cold will become more severe. Thus, taking hot medicines may result in cold symptoms, indicating that Yang deficiency should not be treated with dispersing methods. Furthermore, summer is inherently hot, yet latent Yin cold resides within, so middle-jiao cold often occurs; winter is inherently cold, yet latent Yang heat resides within, so internal heat often occurs. If one ignores this and insists on using cold herbs in summer to treat hyperactive fire, or hot herbs in winter to treat hyperactive cold, then for patients with middle-cold obstructing Yang, taking cold herbs will paradoxically cause heat; for patients with middle-heat obstructing cold, taking hot herbs will paradoxically cause cold. These are all examples of "treating prosperity" leading to contrary outcomes.
Yang is constantly in excess, while Yin is constantly deficient. This principle applies to all things in heaven and earth, and to the entire human body; it does not directly equate Qi with Yang and Blood with Yin. The classics state: "Within Yang there is Yin, and within Yin there is Yang," which precisely means that "solitary Yang cannot generate, and solitary Yin cannot grow." Let us discuss this from the perspective of treatment methods and accompanying symptoms: Qi deficiency refers to Yin deficiency within Qi; the treatment method involves using Si Jun Zi Tang (Four Gentlemen Decoction) to tonify the Yin within Qi. Blood deficiency refers to Yin deficiency within Blood; the treatment method involves using Si Wu Tang (Four Substance Decoction) to nourish the Yin within Blood. Yang deficiency refers to the deficiency of Original Yang in the Heart Meridian, often manifesting as aversion to cold due to a lack of Fire; the treatment method involves adding Gui Zhi (Cinnamon Twig) to Qi-tonifying herbs, and in severe cases, using San Jian Zhong Tang (Three Builders Middle-Jiao Decoction) or Zheng Yang San (Upright Yang Powder). Yin deficiency refers to the deficiency of True Yin in the Kidney, often manifesting as high fever due to a lack of Water; the treatment method involves adding Zhi Mu (Anemarrhena Rhizome) and Huang Bai (Phellodendron Bark) to Blood-nourishing herbs, or using Da Bu Yin Wan (Great Tonification of Yin Pill) or Zi Yin Di Huang Wan (Nourish Yin Rehmannia Pill). When True Yuan is extremely depleted, one should initially avoid using Gui Zhi (Cinnamon Twig) and Fu Zi (Aconite Lateral Root), lest they assist Fire and scorch True Yin. In cases of Original Yang collapse, one should not administer Xin San Dan Shen agents like Xiong (Ligusticum Chuanxiong Rhizome) and Fu Ling (Poria), lest they open the Cou Li (pores/skin texture) and leak Qi. Ignorant practitioners believe that Qi deficiency is equivalent to Yang deficiency and should only be treated with Si Jun Zi Tang, absolutely avoiding Xiong and Fu Ling. They believe Blood deficiency is equivalent to Yin deficiency and should only be treated with Si Wu Tang, strictly avoiding Ren Shen (Ginseng Radix) and Mai Dong (Ophiopogon Tuber). They do not realize that "tonifying Qi for Blood loss" is a method used by ancient sages. Only when True Yin is extremely depleted, leading to labor-induced steaming and coughing, must one use Ren Shen (Ginseng Radix) and Mai Dong (Ophiopogon Tuber); otherwise, fearing Lung Heat damaging the Lung, one might find them unable to withstand the pathogen, thereby worsening the condition. One should not adhere rigidly to these distinctions.