夫病有虚实，虚因正气不足。实因邪气有余。凡外入之病多有余，如六气所感，饮食所
伤之
类。内出之病多不足，如七情伤气，劳欲伤精之类是也。实者宜泻，经曰∶寒者热之，热者
寒之，坚者削之，客者除之，结者散之，留者攻之，湿者行之，强者泻之之属，皆用泻之法
也。虚者宜补，经云∶散者收之，燥者润之，急者缓之，脆者坚之，衰者补之，劳者温之，
损者益之，惊者平之之属，皆用补之法也。虚实之治，大概如此。但当今之人，实者无几，
虚者七八，病实者，其来速，故其治易。病虚者，损伤有渐，不易复元，故其治难。治实者
，但如为少壮新邪，则可攻可拔，犹足无虑。治虚者，但察其根本有亏，有倏忽变幻，可无
虑乎？故治实之法，外有余，可散其表；内有余，可攻其里；气有余，可攻其滞；血有余、
可逐其瘀。方法星罗，可无赘也。惟虚损之治法有未尽，不得不详其要也。夫人之虚损，有
先天不足，有后天不足。先天者，由于禀受，宜倍加谨慎，急以后天之事补之，庶可延年，
使觉之不早，而漫不为意，则未有不夭折者也。后天者，由于劳伤，宜速加警省，即以性情
药石调摄之，使治之不早，而迁延讳疾，则未有不噬脐者也。凡劳伤之辨，劳者劳其神气，
伤者伤其形体。如喜怒思虑则伤心，忧愁恐哀则伤肺，是皆劳其神气也。饮食失度则伤脾，
起居不慎则伤肝，色欲纵肆则伤肾，是皆伤其形体也。损其肺者伤其气，为皮焦而毛落；损
其心者伤其神，为血脉少而不荣于脏腑，此自上而伤也。损其肝者伤其筋，缓而不能收持；
损其肾者伤其精，为骨髓消减，痿弱不能起，此自下而伤也。损其脾者，伤其仓禀之本，为
饮食不为肌肤，此自中而伤也。夫心肺伤而神色败，肝肾损而形体痿，脾胃伤而饮食不化，
感此病者，皆损之类也。《难经》云∶损其肺者益其气，损其心者调其营卫，损其脾者调其
饮食，适其寒温，损其肝者缓其中，损其肾者益其精，此治损之法也。然所损虽分五脏，而
五脏所藏，无非精与气耳。夫精为阴，人之水也。气为阳，人之火也。水火得其平，则为精
为气；失其和，则为寒为热。此因偏损，所以致有偏胜。故水中不可无火，无火则阴胜而寒
病生。火中不可无水，无水则阳胜而热病起。但当详辨阴阳，则虚损之治，无余议矣。如水
亏者，阴虚也，则宜大补真阴，不可再伐阳气。火亏者，阳虚也，只宜大补元阳，不可再伤
阴气。盖阴既不足，而复伐其阳，阳亦亡矣。阳既不足，而复伐其阴，阴亦损矣。夫治虚治
实，本自不同。实者阴阳固自有余，但去所余而得其平。虚者阴阳本有不足，再去所有，则
二者俱败，其能生乎？故治虚之要，凡阴虚多热者，最忌辛燥，恐助阳邪也，尤忌苦寒，恐
伐生阳也，惟喜纯甘壮水之剂，补阴以配阳，则刚为柔克，虚火自降，而阳归乎阴矣。阳虚
多寒者，最嫌凉润，恐助阴邪也，尤忌辛散，恐伤阴气也，只宜甘温益火之品，补阳以消阴
，则柔得其主，而沉寒自敛，而阴从乎阳矣。是以气虚者，宜补其上；精虚者，宜补其下；
阳虚者，宜补而兼暖；阴虚者，宜补而兼清。此固阴阳之治辨也。其有气因精而虚者，自当
补精以化气；精因气而虚者，自当补气以生精，又如阳失阴而离者，非补阴何以收散亡之气
；如阳失火而败者，非补火何以苏随散之阳，此又阴阳相济之妙用也。故善补阳者，必于阴
中求阳，则阳得阴助，而生化无穷；善补阴者，必于阳中求阴，则阴得阳而升，泉源不渴，
故以精气分阴阳，则阴阳不可离；以寒热分阴阳，则阴阳不可混。此又阴阳邪正之离合也，
知阴阳邪正之治，则阴阳和而生道得矣。经曰∶不能治其虚，何问其余，此之谓也。
疾病有虚证和实证之分，虚证是因为正气不足。实证是因为邪气有余。凡是外感引起的病多属于有余（实证），如感受六淫邪气、饮食损伤身体这类情况。内伤引起的病多属于不足（虚证），如七情（喜、怒、忧、思、悲、恐、惊）损伤气机、劳倦房事损伤精气这类情况是也。实证应当用泻法治疗，医经说：寒证用热药治，热证用寒药治，坚积者削之，客邪者除之，郁结者散之，留滞者攻之，湿邪者行气化湿，强盛者泻之，这些都属于使用泻法。虚证应当用补法治疗，医经说：涣散者收之，干燥者润之，拘急者缓之，脆弱者坚固之，衰弱者补之，劳损者温之，亏损者益之，惊恐者平之，这些都属于使用补法。治疗虚实的大致原则就是这样。但是当今之人，实证很少，虚证占七八成。患实证的病，发病迅速，所以治疗容易。患虚证的病，损伤是逐渐形成的，不容易恢复元气，所以治疗困难。治疗实证，如果是年轻力壮之人感受新邪，那么可以攻下或拔除病邪，还足以不用担心。治疗虚证，只要察知根本元气亏虚，病情可能突然变化，难道可以不用担心吗？所以治疗实证的方法，表位有余，可以发散表邪；里位有余，可以攻逐里邪；气分有余，可以疏通气滞；血分有余，可以祛除瘀血。方法众多，无需赘述。只有治疗虚损的方法还有未尽之处，不得不详细说明其要点。人的虚损，有先天不足，有后天不足。先天的，由于禀赋遗传，应当加倍谨慎，急切地通过后天的调养来弥补，或许可以延年益寿，如果觉察得不早，而漫不经心，那么没有不夭折的。后天的，由于劳累损伤，应当迅速警醒反省，立即用性情修养和药物调理摄生，如果治疗不及时，而拖延隐瞒病情，那么没有不后悔莫及的。大凡劳伤的辨别，劳是指劳损神气，伤是指损伤形体。如喜怒思虑过度则伤心，忧愁恐惧悲哀则伤肺，这些都是劳损神气。饮食无节制则伤脾，起居不慎则伤肝，纵欲过度则伤肾，这些都是损伤形体。损伤肺脏，伤及肺气，表现为皮肤焦枯、毛发脱落；损伤心脏，伤及心神，表现为血脉少而不荣养脏腑，这是从上而下损伤。损伤肝脏，伤及筋脉，表现为筋脉松弛而不能收持；损伤肾脏，伤及精髓，表现为骨髓消减，痿弱不能起身，这是从下而上损伤。损伤脾脏，伤及仓廪之本（消化功能），表现为饮食不能转化为肌肉肌肤，这是从中部损伤。心肺受伤则神色败坏，肝肾受损则形体痿废，脾胃受伤则饮食不化，感染这些病症的人，都属于虚损一类。《难经》说：损伤肺脏要益其气，损伤心脏要调和营卫，损伤脾脏要调节饮食，适应寒温，损伤肝脏要舒缓其中气，损伤肾脏要益其精，这就是治疗虚损的方法。然而所损虽然分为五脏，但五脏所藏，无非是精与气罢了。精属于阴，是人的水；气属于阳，是人的火。水火得到平衡，就化为精和气；失去和谐，就产生寒和热。这是因为偏颇损伤，所以导致偏胜。所以水中不可无火，无火则阴胜而生寒病。火中不可无水，无水则阳胜而生热病。只当详细辨别阴阳，那么虚损的治疗，就没有什么可争议的了。如水液亏损，就是阴虚，则应当大补真阴，不可再伐伤阳气。火气亏损，就是阳虚，只宜大补元阳，不可再损伤阴气。因为阴既然不足，如果再伐伤其阳，阳也就亡失了。阳既然不足，如果再伐伤其阴，阴也就受损了。治疗虚证和治疗实证，本来就不相同。实证阴阳固然是有余，只是去除所余而达到平衡。虚证阴阳本来就有不足，再去去除所谓的“有余”，那么两者都败坏了，还能生存吗？所以治疗虚证的关键，凡是阴虚多热的，最忌辛燥，恐怕助长阳邪，尤其忌苦寒，恐怕伐伤生发之阳，只喜欢纯甘壮水的药剂，补阴以配合阳，则刚强被柔和克制，虚火自然下降，而阳归于阴了。阳虚多寒的，最嫌凉润，恐怕助长阴邪，尤其忌辛散，恐怕损伤阴气，只宜甘温益火的药品，补阳以消除阴，则柔弱得到主宰，而沉寒自然收敛，而阴顺从于阳了。因此气虚的，宜补其上焦；精虚的，宜补其下焦；阳虚的，宜补而兼暖；阴虚的，宜补而兼清。这确实是阴阳治疗的辨别。其中有因精虚而导致气虚的，自然应当补精以化气；因气虚而导致精虚的，自然应当补气以生精。又如阳气失却阴液而离散者，不补阴怎么能收敛散亡之气；如阳气失却火源而败坏者，不补火怎么能苏醒随散之阳，这又是阴阳相互济助的妙用。所以善于补阳的人，必须在阴中求阳，那么阳得到阴的帮助，而生化无穷；善于补阴的人，必须在阳中求阴，那么阴得到阳的升发，泉源不枯竭，所以以精气分阴阳，则阴阳不可分离；以寒热分阴阳，则阴阳不可混淆。这又是阴阳邪正的离合关系，懂得阴阳邪正的治疗，那么阴阳调和而生道就得到了。医经说：不能治疗虚证，何必问其他，说的就是这个道理。
Diseases are categorized into deficiency (Xu, 虚) and excess (Shi, 实). Deficiency arises from a lack of Zheng Qi (Righteous Qi, 正气), while excess results from an abundance of Xie Qi (Pathogenic Qi, 邪气). Diseases originating externally are mostly excess patterns, such as those caused by the Six Exogenous Pathogens (Liu Qi, 六气) or dietary injury. Diseases originating internally are mostly deficiency patterns, such as those caused by emotional injury to Qi (Seven Emotions, 七情) or laborious exertion and sexual indulgence injuring Jing (Essence, 精). For excess patterns, purgation is indicated. The Classics state: "Treat cold with heat, treat heat with cold; reduce hardness, eliminate invaders, disperse knots, attack stagnation, promote dampness, purge strength." These all belong to the method of purgation. For deficiency patterns, tonification is indicated. The Classics state: "Astringe dispersion, moisten dryness, relieve urgency, strengthen fragility, tonify decline, warm exhaustion, benefit loss, calm fright." These all belong to the method of tonification. The general principles for treating deficiency and excess are as described above. However, in contemporary times, true excess cases are rare, whereas deficiency accounts for seven or eight out of ten. Excess diseases arise rapidly and are thus easier to treat. Deficiency diseases develop gradually through damage and are difficult to recover from, making them harder to treat. When treating excess, if it is a new pathogen affecting a young and strong individual, one can attack or extract the pathogen, and there is little cause for concern. When treating deficiency, once one observes that the root essence is depleted, sudden changes may occur; how can one remain unconcerned? Therefore, the methods for treating excess are: if there is excess at the exterior, disperse the exterior; if there is excess at the interior, attack the interior; if there is excess in Qi, resolve stagnation; if there is excess in Blood, expel stasis. There are numerous methods, so no further elaboration is needed. Only the methods for treating deficiency and depletion require detailed explanation. Human deficiency and depletion stem from either congenital insufficiency or acquired insufficiency. Congenital insufficiency arises from endowment; one must be extremely cautious and urgently supplement it through postnatal care to prolong life. If not recognized early and ignored, premature death is inevitable. Acquired insufficiency arises from labor and injury; one must be vigilant and regulate it through mental cultivation and medicinal therapy. If treatment is delayed and illness is concealed, regret will come too late. Regarding the differentiation of labor and injury: "Labor" refers to the exhaustion of Shen Qi (Spirit and Qi, 神气), while "injury" refers to damage to the physical form. Joy, anger, and overthinking injure the Heart; sorrow, fear, and grief injure the Lungs; these are forms of exhausting Shen Qi. Irregular diet injures the Spleen; careless lifestyle injures the Liver; excessive sexual desire injures the Kidney; these are forms of damaging the physical form. Damage to the Lung injures its Qi, manifesting as scorched skin and falling hair. Damage to the Heart injures its Shen, manifesting as insufficient blood vessels failing to nourish the Zang-Fu organs; this is damage from above. Damage to the Liver injures its sinews, manifesting as laxity and inability to hold; damage to the Kidney injures its Essence, manifesting as reduced marrow, flaccidity, and inability to rise; this is damage from below. Damage to the Spleen injures the root of granary storage, manifesting as food failing to transform into muscle and flesh; this is damage from the middle. When the Heart and Lungs are damaged, Spirit and color deteriorate; when the Liver and Kidneys are damaged, the physical form becomes flaccid; when the Spleen and Stomach are damaged, food fails to digest. Those suffering from these conditions fall under the category of deficiency and depletion. The *Nan Jing* states: "For lung damage, benefit Qi; for heart damage, harmonize Ying and Wei; for spleen damage, regulate diet and adapt to cold and warmth; for liver damage, soothe the interior; for kidney damage, benefit Essence." This is the method for treating depletion. Although damage is divided among the Five Zang Organs, what they store is nothing but Essence and Qi. Essence is Yin, the water of man; Qi is Yang, the fire of man. When water and fire are balanced, they become Essence and Qi; when harmony is lost, cold and heat arise. Due to partial damage, partial excess occurs. Thus, within water (Yin), fire (Yang) must not be absent; without fire, Yin prevails and cold disease arises. Within fire (Yang), water (Yin) must not be absent; without water, Yang prevails and heat disease arises. One must carefully differentiate Yin and Yang, then the treatment of deficiency and depletion leaves no room for debate. If Water is deficient, it is Yin deficiency; one should greatly tonify True Yin and must not further attack Yang Qi. If Fire is deficient, it is Yang deficiency; one should only greatly tonify Original Yang and must not further injure Yin Qi. Since Yin is already insufficient, attacking Yang would lead to the loss of Yang. Since Yang is already insufficient, attacking Yin would further damage Yin. Treating deficiency and excess are fundamentally different. In excess, Yin and Yang are naturally abundant; one merely removes the excess to achieve balance. In deficiency, Yin and Yang are inherently insufficient; removing what remains leads to the failure of both, how can life be sustained? Therefore, the key to treating deficiency is: for Yin deficiency with much heat, pungent-dry herbs are strictly contraindicated as they may aid Yang pathogens; bitter-cold herbs are especially contraindicated as they may attack generating Yang. One prefers purely sweet formulas that strengthen water, tonifying Yin to match Yang, so that rigidity is subdued by softness, defying fire descends naturally, and Yang returns to Yin. For Yang deficiency with much cold, cooling-moistening herbs are disliked as they may aid Yin pathogens; pungent-dispersing herbs are especially contraindicated as they may injure Yin Qi. One should use sweet-warm items that benefit fire, tonifying Yang to dissipate Yin, so that softness finds its master, deep cold naturally consolidates, and Yin follows Yang. Thus, for Qi deficiency, tonify the upper Jiao; for Essence deficiency, tonify the lower Jiao; for Yang deficiency, tonify with warming; for Yin deficiency, tonify with clearing. This is the differentiation of Yin and Yang treatment. If Qi is deficient due to Essence deficiency, one should tonify Essence to generate Qi; if Essence is deficient due to Qi deficiency, one should tonify Qi to generate Essence. Furthermore, if Yang has separated from Yin, how else can scattered Qi be gathered but by tonifying Yin? If Yang has failed due to lack of fire, how else can dispersed Yang be revived but by tonifying fire? This is the subtle application of mutual assistance between Yin and Yang. Therefore, those skilled in tonifying Yang must seek Yang within Yin, so that Yang receives Yin's assistance and generation is endless. Those skilled in tonifying Yin must seek Yin within Yang, so that Yin receives Yang's rising power and the spring source does not dry up. Thus, dividing Yin and Yang by Essence and Qi shows they cannot be separated; dividing Yin and Yang by cold and heat shows they cannot be confused. This is the separation and union of Yin-Yang, pathogenic and righteous factors. Understanding the treatment of Yin-Yang and pathogenic-righteous dynamics allows for the harmony of Yin and Yang and the attainment of the Dao. The Classics say: "If one cannot treat deficiency, why ask about anything else?" This is what is meant.