灵枢经·行针 Conducting the Needle
黄帝问于歧伯曰：余闻九针于夫子，而行之于百姓，百姓之血气，各不同形，或神动而气先针行；或气与针相逢；或针已出，气独行；或数刺乃知；或发针而气逆；或数刺病益剧。凡此六者，各不同形，愿闻其方。
歧伯曰：重阳之人，其神易动，其气易往也。黄帝曰：何谓重阳之人？歧伯曰：重阳之人，熇熇高高，言语善疾，举足善高，心肺之藏气有馀，阳气滑盛而扬，故神动而气先行。
黄帝曰：重阳之人而神不先行者，何也？歧伯曰：此人颇有阴者也。黄帝曰：何以知其颇有阴也。歧伯曰：多阳者，多喜；多阴者，多怒，数怒者，易解，故曰颇有阴。其阴阳之离合难，故其神不能先行也。
黄帝曰：其气与针相逢，奈何？歧伯曰：阴阳和调，而血气淖泽滑利，故针入而气出，疾而相逢也。
黄帝曰：针已出而气独行者，何气使然？歧伯曰：其阴气多而阳气少，阴气沉而阳气浮者内藏，故针已出，气乃随其后，故独行也。
黄帝曰：数刺乃知，何气使然？歧伯曰：此人之多阴而少阳，其气沉而气往难，故数刺乃知也。
黄帝曰：针入而气逆者，何气使然？歧伯曰：其气逆与其数刺病益甚者，非阴阳之气，浮沉之势也。此皆粗之所败，工之所失，其形气无过焉。
Huangdi asked Qibo: 'I have learned of the nine needles from you, Master, and have put them into practice among the common people. Yet the blood and qi of the common people take differing forms: in some, the spirit stirs and the qi moves ahead of the needle itself; in some, the qi and the needle arrive together; in some, once the needle is withdrawn, the qi continues to move on its own; in some, only after repeated needling is the response felt; in some, upon inserting the needle the qi rebels; and in some, repeated needling only worsens the disease. These six patterns each take a different form — I wish to hear the explanation for them.'
Qibo said: 'In a person of doubled yang, the spirit is easily stirred and the qi easily moves forth.' Huangdi said: 'What is meant by a person of doubled yang?' Qibo said: 'A person of doubled yang is fiery and expansive in manner, quick and animated in speech, and lifts his feet high when walking; the qi of his heart and lung viscera is in surplus, and his yang qi is smooth, abundant, and outwardly manifest — hence his spirit stirs and his qi moves ahead of the needle.'
Huangdi said: 'Why is it that in some persons of doubled yang, the spirit does not move ahead of the needle?' Qibo said: 'Such a person still has a considerable measure of yin within him.' Huangdi said: 'How can one know that he has a considerable measure of yin?' Qibo said: 'One with abundant yang is much given to joy; one with abundant yin is much given to anger, though such frequent anger is also easily dispelled — hence it is said that he has a considerable measure of yin. Since the separation and union of his yin and yang are difficult to resolve, his spirit is unable to move ahead of the needle.'
Huangdi said: 'What of the case where the qi and the needle arrive together?' Qibo said: 'In such a person, yin and yang are harmonious and well regulated, and blood and qi are moist and smoothly flowing; hence when the needle enters, the qi issues forth at once, and the two meet swiftly together.'
Huangdi said: 'What qi causes the needle, once withdrawn, to be followed by the qi moving on its own?' Qibo said: 'In such a person, yin qi is abundant and yang qi scant; the yin qi lies deep while the yang qi, though floating, remains stored within — hence, once the needle is withdrawn, the qi follows after it, moving on its own.'
Huangdi said: 'What qi causes the response to be felt only after repeated needling?' Qibo said: 'Such a person has abundant yin and scant yang; his qi lies deep and moves forth only with difficulty, hence the response is felt only after repeated needling.'
Huangdi said: 'What qi causes the qi to rebel when the needle enters?' Qibo said: 'Where the qi rebels, and where repeated needling only worsens the disease, this is not due to the disposition of yin and yang qi, nor to whether they lie deep or float near the surface — in every such case, the fault lies with the unskilled practitioner and the error of poor technique; the patient's own bodily form and qi are not at fault.'