之募原也。六腑之膜原者。连于肠胃之脂膜也。相失者。不与卫气相遇也。盖六腑之募原。其道更远。气有所不到。故
有时相失。不能相得其邪。故或间二日。或数日乃作也。倪冲之曰。藏之膜原而间日发者。乃胸中之膈膜。其道近。六
腑之膜原。更下而远。故有间二日。或至于数日也。张介宾曰。按本经言疟之间二日。及数日发者。以邪气深客于六
腑之间。时与卫气相失。其理甚明。丹溪以作于子午卯酉日者。为少阴疟。作于寅申巳亥日者。为厥阴疟。作于辰戌丑
未日者。为太阴疟。此不过以六气司天之义为言。然子午虽曰少阴。而卯酉则阳明矣。巳亥虽曰厥阴。而寅申则少阳矣。
丑未虽曰太阴。而辰戌则太阳矣。如三日作者。犹可借此为言。若四五日者。又将何以辨之。殊属牵强。倘按此施治。
未必无误。学人不可执以为训。马玄台曰。本经言间日数日发者。邪与卫气不相值。何丹溪乃以为三日一发者。受病
一年半。间日一发者。受病半年。一日一发者。受病一年。不知何据为然。董帷园曰。看书当参讨经义。庶不为前人
所欺。）疟者。阴阳更胜也。或甚或不甚。故或渴或不渴。（言阴阳更胜。而有甚与不甚。故阳热甚则渴。或不甚则不渴
矣。）帝曰。论言夏伤于暑。秋必病疟。今疟不必应者。何也。（言有不必夏伤于暑。而为病疟者也。）岐伯曰。此应四
时者也。其病异形者。反四时也。其以秋病者寒甚。以冬病者寒不甚。以春病者恶风。以夏病者多汗。（伯言夏伤于暑。
秋必病疟者。此应四时者也。应四时者。随四时阴阳之气。升降出入而为病也。其病异形者。反四时也。反四时者。非
留蓄之邪。乃感四时之气而为病也。秋时阳气下降。天气新凉。故感秋凉之气。而为病者寒甚。冬时阳气伏藏于内。即
受时行之寒。得阳气以化热。故寒不甚。春时阳气始出。天气尚寒。故恶风。夏时阳气外泄。腠理空疏。故多汗。此随
感四时之邪。而即为病疟也。倪冲之曰。春伤于风。故恶风。夏伤于暑。故多汗。秋伤于湿。故寒甚。冬伤于寒。则为
病热。故寒不甚。盖言风寒暑湿之邪。在四时而皆能病疟也。）帝曰。夫病温疟与寒疟。而皆安舍。舍于何脏。（此复
问前节温疟之病因。是以帝问温疟与寒疟。病皆安舍。而伯只答其温疟焉。盖寒疟之因。已谕悉于前矣。但前节以先伤
于风。后伤于寒。为温疟。此论先出于阳。后入于阴。为先热后寒。一论在天阴阳之邪。一论形身中之阴阳出入。文义
虽殊。而理则合一）岐伯曰。温疟者。得之冬中于风。寒气藏于骨髓之中。至春则阳气大发。邪气不能自出。因遇大暑。
脑髓烁。肌肉消。腠理发泄。或有所用力。邪气与汗皆出。此病藏于肾。其气先从内出后寒。名曰温疟。（藏真下于肾。
肾藏骨髓之气也。冬气通于肾。故邪藏于骨髓之中。而内与肾气相合。夫至春阳气大发。而邪不能自出者。邪藏于骨髓
之中。而气行骨外故也。脑为精髓之海。脑髓烁者。暑气盛而精髓烁热也。肌肉消者。腠理开而肌肉消疏也。汗乃肾藏
精髓之所化。或有所用力。则伤动其肾气。是以所藏之邪。得与汗共并而出矣。夫骨气与肾气相合。故病气藏于肾。其
气先从内出之外也。从内出外。则阴虚而阳盛。阳盛则热矣。气从内出之外。故病复反入之阴。张兆璜曰。故先热而
后寒者。名曰温疟。其但热而不寒者。名曰瘅疟矣。故字宜着眼。）帝曰。瘅疟何如。岐伯曰。瘅疟者。肺素有热。气
盛于身。厥逆上冲。中气实而不外泄。因有所用力。腠理开。风寒舍于皮肤之内。分肉之间而发。发则阳气盛。阳气盛
而不衰则病矣。其气不反于阴。故但热而不寒。气内藏于心。而外舍于分肉之间。令人消烁脱肉。故命曰瘅疟。帝曰善。
（此复论瘅疟之有因于内热者也。肺主周身之气。肺素有热。故气盛于身。其气厥逆上冲。故不泄于外。而但实于中。
此外内皆实者矣。气止实于外。则邪不能外侵。故因有所用力。腠理开而后邪舍于皮肤之内。中气实则邪不能内入。故
其气不及于阴。而单发于阳也。心主血脉之气。气内藏于心者。谓邪藏于血脉之中。而气内通于心也。内藏于血脉之里。
外舍于分肉之间。阳气盛而无阴气以和之。是以阳热不衰。而令人消烁脱肉也。前节论外因之瘅疟。此论兼有内因之瘅
疟也。故金匮要略曰。阴气孤绝。阳气独发。则热而少气烦冤。手足热而欲呕。名曰瘅疟。若但热不寒者。邪气内藏于
心。外舍分肉之间。令人消烁脱肉。是阴气绝而阳气独发者。名曰瘅疟。若但热不寒者。亦名瘅疟。是瘅疟之有二证也。
张兆璜曰。邪舍于血脉之中。而气内藏于心。与邪藏于骨髓之中。而病藏于肾者同义。但肾为阴脏。故邪复反入之阴。
心为阳脏。故气不及于阴。而单发于阳也。）
This is the *muyuan* (Moyuan, membrane origin) of the six fu organs. The "membrane origin" of the six fu organs refers to the fatty membranes connecting the stomach and intestines. "Xiangshi" (missing each other) means that the pathogenic factor does not encounter the Wei Qi (Defensive Qi). Because the Muyuan of the six fu organs is located further away, the Qi may not reach it at times, causing a miss. Consequently, the pathogenic factor cannot synchronize with the Wei Qi for attack, so malaria may occur every two days or after several days. Ni Chongzhi stated: For malaria occurring every other day due to pathogens hiding in the membrane origin of the zang organs, this refers to the diaphragmatic membrane in the chest, which has a shorter pathway. The membrane origin of the six fu organs is lower and further away, hence the occurrence every two days or several days. Zhang Jiebin stated: According to the *Neijing*, malaria occurring every two days or several days happens because the pathogenic factor deeply resides between the six fu organs and often misses the Wei Qi; this principle is very clear. Danxi believed that attacks on Zi, Wu, Mao, and You days constitute Shaoyin Malaria; attacks on Yin, Shen, Si, and Hai days constitute Jueyin Malaria; and attacks on Chen, Xu, Chou, and Wei days constitute Taiyin Malaria. This merely borrows the theory of the Six Qi ruling the year. However, although Zi and Wu belong to Shaoyin, Mao and You belong to Yangming; although Si and Hai belong to Jueyin, Yin and Shen belong to Shaoyang; although Chou and Wei belong to Taiyin, Chen and Xu belong to Taiyang. If it occurs every three days, one might borrow this explanation; but if it occurs every four or five days, how can it be distinguished? This is indeed forced. If treatment is applied according to this, errors are likely. Students should not take this as a standard. Ma Xuantai said: The *Neijing* states that attacks every other day or several days occur because the pathogen and Wei Qi do not meet. Why did Danxi claim that those attacking every three days have been sick for a year and a half; those attacking every other day for half a year; and those attacking daily for one year? I do not know what basis he had. Dong Weiyuan said: When reading, one must investigate the meaning of the classics to avoid being deceived by predecessors.
Malaria arises from the alternating dominance of Yin and Yang. The dominance may be severe or mild; therefore, some patients experience thirst, while others do not. (This explains that due to the alternation of Yin and Yang, with varying degrees of severity, severe Yang heat causes thirst, while mild heat does not.)
The Yellow Emperor asked: The treatises state that summer injury by Summer-heat leads to autumn malaria. Now, why do some cases of malaria not conform to this rule? (Meaning there are cases where malaria occurs without summer injury by Summer-heat.)
Qibo replied: These cases follow the laws of the Four Seasons. Those presenting with atypical symptoms violate the laws of the Four Seasons. Malaria occurring in Autumn presents with severe cold; in Winter, with mild cold; in Spring, with aversion to wind; and in Summer, with profuse sweating. (Qibo explained that "summer injury by Summer-heat leads to autumn malaria" follows the Four Seasons. Following the Four Seasons means illness arises according to the ascending, descending, exiting, and entering of Yin-Yang Qi in the four seasons. Atypical cases violate these laws, meaning the pathogen is not retained but results from contracting the Qi of the specific season. In Autumn, Yang Qi descends and the weather becomes cool; thus, contracting Autumn coolness results in severe cold. In Winter, Yang Qi hides internally; even if contracted by seasonal cold, internal Yang transforms it into heat, resulting in mild cold. In Spring, Yang Qi begins to emerge, but the weather remains cold, causing aversion to wind. In Summer, Yang Qi escapes outward, pores are open and loose, causing profuse sweating. Thus, malaria occurs immediately upon contracting the pathogenic factors of the respective season. Ni Chongzhi added: Spring injury by Wind causes aversion to wind; Summer injury by Summer-heat causes profuse sweating; Autumn injury by Dampness causes severe cold; Winter injury by Cold manifests as heat disease, hence mild cold. This indicates that Wind, Cold, Summer-heat, and Dampness can all cause malaria in their respective seasons.)
The Yellow Emperor asked: Regarding Warm Malaria (*Wen Nue*) and Cold Malaria (*Han Nue*), where do these pathogens reside? Which Zang organ do they inhabit? (This re-asks about the etiology of Warm Malaria mentioned earlier. The Emperor asks about the residence of both, but Qibo only answers for Warm Malaria, as the cause of Cold Malaria was already fully explained. Previously, Warm Malaria was defined as first injuring Wind then Cold. Here, it is described as emerging from Yang first then entering Yin, presenting as heat followed by cold. One discusses Heavenly Yin-Yang pathogens; the other discusses the exit and entry of Yin-Yang within the body form. Although the textual meanings differ, the underlying principles are unified.)
Qibo replied: Warm Malaria originates from winter exposure to Wind. Cold Qi hides within the Marrow. By spring, when Yang Qi expands vigorously, the pathogen cannot expel itself. If encountered with intense Summer-heat, the brain marrow is scorched, muscles waste, and pores open. If physical exertion occurs, the pathogen exits along with sweat. This disease resides in the Kidney. The Qi emerges from the interior to the exterior first, followed by chills; this is named Warm Malaria. (The True Qi of the Kidneys resides below; the Kidney stores the Qi of the Marrow. Winter Qi connects to the Kidney, so pathogens hide in the marrow and combine with Kidney Qi. When spring Yang Qi expands, the pathogen cannot self-expel because it is hidden in the marrow while Qi circulates outside the bone. The Brain is the sea of Essence and Marrow; "scorched marrow" implies intense Summer-heat scorching the essence. "Muscle wasting" implies open pores and loosened muscles. Sweat is transformed from the Essence stored in the Kidney. Physical exertion disturbs Kidney Qi, allowing the stored pathogen to exit combined with sweat. Since Bone Qi combines with Kidney Qi, the disease Qi resides in the Kidney. The Qi moves from interior to exterior. Moving from interior to exterior leads to Yin deficiency and Yang excess; Yang excess generates heat. After moving from interior to exterior, the pathogen returns to Yin. Zhang Zhaohuang noted: Therefore, heat preceding cold is named Warm Malaria. Heat alone without cold is named Dan Malaria. The character "Gu" (therefore) should be emphasized.)
The Yellow Emperor asked: What is Dan Malaria?
Qibo replied: Dan Malaria arises because the Lungs possess inherent heat, causing Qi to be excessive throughout the body. Qi rebels upward and inward. The Middle Jiao Qi is full and does not vent outward. Due to physical exertion, pores open, and Wind-Cold settles inside the skin and between the muscle layers, triggering an attack. During the attack, Yang Qi becomes excessive. If Yang Qi remains excessive without declining, disease ensues. The Qi does not return to Yin; thus, there is heat without cold. The Qi resides internally in the Heart and externally between the muscle layers, causing emaciation and wasting. Hence, it is named Dan Malaria.
The Yellow Emperor said: Excellent. (This section discusses Dan Malaria caused by internal heat. The Lungs govern the Qi of the whole body. Inherent Lung heat causes systemic Qi excess. Rebel Qi moves upward and inward, preventing external venting and causing internal fullness. This represents internal and external fullness. If Qi were only full externally, pathogens could not invade externally; thus, after exertion opens pores, pathogens settle inside the skin. Internal Qi fullness prevents pathogens from entering internally, so the Qi does not reach Yin but manifests solely in Yang. The Heart governs Blood vessel Qi. "Qi residing in the Heart" means pathogens reside in the blood vessels, with Qi connecting internally to the Heart. Residing deep in the blood vessels and settling between muscle layers, Yang Qi is excessive without Yin to harmonize it, leading to unceasing Yang heat and emaciation. The previous section discussed exogenous Dan Malaria; this section discusses Dan Malaria with endogenous causes. Thus, the *Jin Gui Yao Lue* states: When Yin Qi is isolated and cut off, and Yang Qi fires alone, there is heat, shortness of breath, vexation, hot hands and feet, and desire to vomit; this is named Dan Malaria. If there is heat without cold, pathogens reside internally in the Heart and externally between muscle layers, causing emaciation; this is Yin Qi cut off and Yang Qi firing alone, named Dan Malaria. If there is heat without cold, it is also named Dan Malaria. This shows two types of Dan Malaria. Zhang Zhaohuang stated: Pathogens settling in blood vessels with Qi residing in the Heart share the same logic as pathogens hiding in marrow with disease residing in the Kidney. However, the Kidney is a Yin organ, so pathogens return to Yin; the Heart is a Yang organ, so Qi does not reach Yin but manifests solely in Yang.)