七十四难曰∶经言春刺井，夏刺荥，季夏刺俞，秋刺经，冬刺合者，何谓也？然∶春刺井者，
邪在肝；夏刺
荥者，邪在心；季夏刺俞者，邪在脾；秋刺经者，邪在肺；冬刺合者邪在肾。
其肝心脾肺肾，而系于春夏秋冬者，何也？然∶五脏一病，辄有五色。假令肝病∶色青者肝也，
臊臭者肝也，喜酸者肝也，喜呼者肝也，喜泣者肝也。其病众多，不可尽言也。四时有数，而并系于春夏
秋冬者也。针之要妙，在于秋毫者也。
七十五难曰∶经言东方实，西方虚，泻南方，补北方，何谓也？然∶金木水火土，当更相平。
东方木也，西方金也。木欲实，金当平之；火欲实，水当平
之；土欲实，木当平之；金欲实，火当平之∶水欲实，土当平之。东方肝也，则知肝实；西方肺也，
则知肺虚。泻南方火，补北方水。南方火，火者木之子也；北方水，水者木之母也。水胜
火，子能令母实，母能令子虚。故泻火补水，欲令金不得平木也。经曰、不能治其虚，何问其余。
此之谓也。
七十六难曰∶何谓补泻？当补之时，何所取气？当泻之时，何所置气？然∶当补之时，从卫取气；
当泻之时，从荣置气。其阳气不足，阴气有余，当先补其阳，而后泻其阴；阴气不足，阳气有余，
当先补其阴，而后泻其阳。荣卫通行，此其要也。
第七十四难说：医经中说“春季针刺井穴，夏季针刺荥穴，长夏（季夏）针刺输穴，秋季针刺经穴，冬季针刺合穴”，这是什么意思呢？回答说：春季针刺井穴，是因为病邪在肝；夏季针刺荥穴，是因为病邪在心；长夏针刺输穴，是因为病邪在脾；秋季针刺经穴，是因为病邪在肺；冬季针刺合穴，是因为病邪在肾。这五脏与春夏秋冬四季相联系，是什么道理呢？回答说：五脏发生病变时，各自会有相应的五色表现。例如肝病：面色发青是肝病的表现，气味臊臭是肝病的表现，口味喜酸是肝病的表现，喜欢呼喊是肝病的表现，喜欢哭泣是肝病的表现。肝病的症状很多，无法一一尽述。四季的变化有定数，并且都关联于春、夏、秋、冬四季。针刺的奥妙精微之处，在于像秋毫那样细微精准。
第七十五难说：医经中说“东方实，西方虚，泻南方，补北方”，这是什么意思呢？回答说：金、木、水、火、土五行应当相互平衡制约。东方属木，西方属金。如果木气过实，应当用金来平抑它；如果火气过实，应当用水来平抑它；如果土气过实，应当用木来平抑它；如果金气过实，应当用火来平抑它；如果水气过实，应当用土来平抑它。东方对应肝，所以知道肝气实；西方对应肺，所以知道肺气虚。治疗上应泻南方的火，补北方的水。南方属火，火是木之子（子行）；北方属水，水是木之母（母行）。水能胜火，根据“子能令母实，母能令子虚”的原理，通过泻火补水，目的是使金气不能正常平抑木气（即防止金克木太过，或理解为通过调节母子关系来间接调节脏腑平衡）。医经说：“不能治疗其虚弱的一面，还问其他什么呢？”说的就是这个道理。
第七十六难说：什么是补法和泻法？施行补法时，从何处获取正气？施行泻法时，将邪气置于何处？回答说：施行补法时，从卫分取气；施行泻法时，向营分置气（引邪外出）。如果阳气不足，阴气有余，应当先补其阳，然后再泻其阴；如果阴气不足，阳气有余，应当先补其阴，然后再泻其阳。使营气和卫气通行顺畅，这就是关键所在。
Difficulty 74 states: The classics say, "In spring, puncture the Jing-Well points; in summer, puncture the Ying-Spring points; in late summer, puncture the Shu-Stream points; in autumn, puncture the Jing-River points; in winter, puncture the He-Sea points." What does this mean? The answer is: In spring, puncturing the Jing-Well points indicates that the pathogenic factor is in the Liver; in summer, puncturing the Ying-Spring points indicates that the pathogenic factor is in the Heart; in late summer, puncturing the Shu-Stream points indicates that the pathogenic factor is in the Spleen; in autumn, puncturing the Jing-River points indicates that the pathogenic factor is in the Lung; in winter, puncturing the He-Sea points indicates that the pathogenic factor is in the Kidney. Why are these five Zang organs associated with the four seasons of spring, summer, autumn, and winter? The answer is: When one of the five Zang organs becomes diseased, it manifests with specific colors. For example, in Liver disease: a bluish complexion indicates Liver disease; a fishy odor indicates Liver disease; a preference for sour taste indicates Liver disease; a tendency to shout indicates Liver disease; a tendency to weep indicates Liver disease. There are many symptoms of Liver disease, which cannot be exhaustively listed. The changes of the four seasons have their fixed patterns and are all associated with spring, summer, autumn, and winter. The subtlety and wonder of acupuncture lie in its precision, down to the finest detail (like the tip of an autumn hair).
Difficulty 75 states: The classics say, "The East is excess, the West is deficiency; drain the South, tonify the North." What does this mean? The answer is: Metal, Wood, Water, Fire, and Earth should mutually balance each other. The East corresponds to Wood, and the West to Metal. If Wood is excessive, Metal should regulate it; if Fire is excessive, Water should regulate it; if Earth is excessive, Wood should regulate it; if Metal is excessive, Fire should regulate it; if Water is excessive, Earth should regulate it. The East corresponds to the Liver, so we know the Liver is excess; the West corresponds to the Lung, so we know the Lung is deficient. Therefore, drain the Fire of the South and tonify the Water of the North. The South corresponds to Fire, and Fire is the Son (Zi) of Wood; the North corresponds to Water, and Water is the Mother (Mu) of Wood. Water overcomes Fire. According to the principle that "the Son can make the Mother full, and the Mother can make the Son empty," by draining Fire and tonifying Water, the intention is to prevent Metal from regulating Wood (specifically, to avoid Metal overcoming Wood excessively due to the imbalance). The classics state, "If you cannot treat the deficiency, what else is there to ask about?" This refers to this principle.
Difficulty 76 states: What are tonification and reduction methods? When tonifying, where is Qi obtained? When reducing, where is Qi placed? The answer is: When tonifying, obtain Qi from the Wei (Defensive) level; when reducing, place Qi into the Ying (Nutritive) level. If Yang Qi is deficient and Yin Qi is excessive, first tonify Yang and then reduce Yin; if Yin Qi is deficient and Yang Qi is excessive, first tonify Yin and then reduce Yang. Ensuring the smooth circulation of Ying and Wei Qi is the key.