凡似疟非疟之病，虽有往来寒热，而时作时止，本非疟之类也。凡大病后，或产后，或
虚损，俱有此证。经曰∶阳虚则外寒，阴虚则内热，阴气上入阳中则恶寒，阳气下入阴中则
恶热。故凡无外邪而病为寒热者，必属虚证。但虚有阴阳之异，而阳虚者必多寒，阴虚者必
多热。阳虚者宜补其阳，如理中汤、十全大补汤加姜桂附子之类，此皆人所易知也。惟阴虚
之证则最不易辨，盖阴中之水虚者，阴虚也；阴中之火虚者，亦阴虚也。如其津液枯燥，精
血耗伤，表里上下，俱多烦热等证，此阴中之水虚也。治宜壮水以配阳，如一阴煎、六味地
黄汤，或加减一阴煎之类主之。其有倏热往来，或面赤如脂，而腹喜热饮，或上热如烙，而
下冷如冰，或喉口大热，而大便不实，此其证虽若热，而脉必细微，或虽洪大而浮空无力者，是
皆阳气无根而孤浮于上，此阴中之火虚也。治宜益火之本，使之归源，如海藏八味地黄丸，
或右归饮之类主之。假热退则真寒见，自可因证而治之也。寒热门论治尤详，所当并察。
温疟一证，在《内经》曰∶温疟者，得之冬中于风寒，至春夏阳气大发而为病，此即正
伤寒之属也。故仲景《伤寒论》有温疟一证，即此是也。此与夏伤暑而秋为疟者，本自不同
，当于伤寒门酌而治之。
凡是类似疟疾但并非真正疟疾的疾病，虽然也有忽冷忽热的症状，但发作有时停止，本质上不属于疟疾一类。凡是大病之后，或产后，或因虚损劳伤，都会出现这种证候。《内经》说：阳气虚弱则体表发寒，阴气虚弱则体内发热，阴气上入阳分则感到恶寒，阳气下入阴分则感到恶热。所以，凡是外无邪气侵袭而表现为寒热往来的病症，必然属于虚证。但是虚证有阳虚和阴虚的区别，阳虚的人大多怕冷，阴虚的人大多怕热。对于阳虚者应当补益阳气，如使用理中汤、十全大补汤加入干姜、肉桂、附子等药物，这些都是人们容易知晓的。只有阴虚的证候最不容易辨别，因为阴中的“水”（真阴）虚弱，是阴虚；阴中的“火”（命门之火）虚弱，也是阴虚。如果津液干枯，精血耗伤，表里上下都出现烦热等症状，这是阴中之水虚。治疗应当壮水之主以制约阳亢，如使用一阴煎、六味地黄汤，或者加减一阴煎等方剂为主治。如果有突然发热又忽冷忽热，或者面色红赤如涂脂，但腹部喜欢热饮，或者上部热得像烧烤，而下部冷得像冰，或者咽喉口腔大热，但大便稀溏不成形，这些症状虽然看似热证，但脉象必定细微，或者虽然洪大但浮取无力，这都是阳气没有根基而孤浮于上，这是阴中之火虚。治疗应当补益火的根本，使阳气回归本源，如使用海藏八味地黄丸，或者右归饮等方剂为主治。假热消退后真寒之象就会显露，自然可以根据证候进行治疗了。关于寒热门的论治非常详细，应当一并考察。
温疟这一证候，在《内经》中说：温疟，是因为冬天感受了风寒，到了春夏季节阳气大发而发病，这实际上属于正伤寒的范畴。所以张仲景《伤寒论》中有温疟这一证候，指的就是这个。这与夏天被暑邪所伤而秋天发作的疟疾，本来就不相同，应当在伤寒门类中斟酌治疗。
Any disease that resembles malaria but is not true malaria, although presenting with alternating chills and fever (Wanglai Hanre), may start and stop intermittently, and essentially does not belong to the category of malaria. Such syndromes commonly occur after severe illnesses, postpartum, or in cases of deficiency consumptive diseases (Xusun). The *Classic of Internal Medicine* (*Neijing*) states: "Yang deficiency leads to external cold; Yin deficiency leads to internal heat. When Yin Qi ascends into the Yang region, there is aversion to cold; when Yang Qi descends into the Yin region, there is aversion to heat." Therefore, any condition manifesting as alternating chills and fever without external pathogenic invasion must be attributed to a deficiency syndrome. However, deficiency syndromes differ between Yang deficiency and Yin deficiency. Those with Yang deficiency tend to have more cold manifestations, while those with Yin deficiency tend to have more heat manifestations. For Yang deficiency, one should tonify Yang, using formulas such as Lizhong Tang (Regulate the Middle Decoction) or Shiquan Dabu Tang (Ten Substance Great Tonifying Decoction) added with Ganjiang (Dried Ginger), Rougui (Cinnamon Bark), and Fuzi (Prepared Aconite Root), which are generally well understood. It is only the Yin deficiency syndrome that is most difficult to differentiate. Deficiency of Water within Yin constitutes Yin deficiency; deficiency of Fire within Yin also constitutes Yin deficiency. If body fluids are dry and exhausted, and essence and blood are depleted, resulting in vexation and heat throughout the interior and exterior, upper and lower parts, this is deficiency of Water within Yin. Treatment should aim to strengthen Water to harmonize Yang, using formulas such as Yiyin Jian (One-Yin Decoction), Liuwei Dihuang Tang (Six-Ingredient Rehmannia Pill), or Jiajian Yiyin Jian (Modified One-Yin Decoction). If there are sudden waves of heat and cold, or a face red like grease, yet the abdomen prefers hot drinks, or the upper body feels hot as if branded while the lower body is cold as ice, or the throat and mouth feel intensely hot while the stool is loose and unformed, these symptoms appear as heat, yet the pulse is necessarily fine and minute, or perhaps surging and floating but empty and weak upon pressure. This indicates that Yang Qi has no root and floats alone upward, constituting deficiency of Fire within Yin. Treatment should benefit the root of Fire to guide it back to its source, using formulas such as Haizang Bawei Dihuang Wan (Haizang's Eight-Ingredient Rehmannia Pill) or Yougui Yin (Right-Restoring Decoction). Once the false heat recedes, the true cold will become apparent, allowing for treatment based on the revealed syndrome. The discussion on treating cold and heat is particularly detailed in the relevant chapter and should be carefully observed.
The syndrome of Warm Malaria (Wen Nue) is described in the *Neijing*: "Warm Malaria arises from contracting wind-cold in winter, and manifests as illness when Yang Qi flourishes greatly in spring and summer." This actually belongs to the category of standard Cold Damage (Shanghan). Therefore, Zhang Zhongjing's *Treatise on Cold Damage Diseases* (*Shanghan Lun*) includes the syndrome of Warm Malaria, referring to this specific condition. This differs fundamentally from malaria caused by summerheat injury in summer manifesting in autumn, and should be treated with discretion within the context of Cold Damage disorders.