阴阳交并，二者乃热病表里俱实者之诊法也。其表里俱实，而复相连互曰交，续自厘清
曰并
。阴交者，里实较盛，故已得汗，而脉尚躁盛；并阳则初似阴交，而复得汗，脉渐静，以里
散表解也。阳交者，表实较盛，故脉常躁盛而不得汗；并阴则初似阳交，而一得汗散热即泄
，以表解里微也。故交者皆死，并者皆生。《脉经》曰∶热病已得汗而脉尚躁盛，此阴脉之
极也，死；其得汗而脉静者，生也。（“得”上当有“复”字。《脉经》热病烦已而汗，脉
当静。太阳病脉反躁盛者，是阴阳交，死；复得汗，脉静者，生。又曰∶热病已得汗，脉尚
躁盛，大热，汗之虽不汗出，若衄，是谓并阳，故活。皆言复汗也。）此合阴交与并阳言之
。又曰∶热病脉常（各本“常”作“尚”涉上而误）躁盛，而不得汗者，此阳脉之极也，死；
脉
躁盛，得汗出者，生也。此合阳交与并阴言之。阴极阳极，即里实盛表实盛之谓。大抵表里
俱实之症，不交则并，不并则交，死生之关，捷于反掌。《史记·仓公传》脉法曰∶热病阴
阳交者死。切之不交，并阴。并阴者，脉顺清而愈。其热虽未尽，犹活也。绎仓公“不交”
“并阴”四字，则知其转易间难逆料矣。诊交之法，又有进退，诸证在《脉经》中。此皆诊
决死生之要，切宜究之。（复得汗以症言，非以治言，故有下之而始得汗者。）
《素问》所言，实止是阴交，于阳交无涉。统称阴阳交者，犹男子阴易、女之阳易，统
称阴阳易也。
阴阳交与并，是用于诊断热病中表证与里证均呈实证状态的诊法。所谓“表里俱实”，如果两者相互纠缠、界限不清，称为“交”；如果随后逐渐理清、分离，称为“并”。
阴交，是指里实邪气较盛，因此患者虽然已经出汗，但脉象依然躁动旺盛；并阳，起初看似阴交，但随后再次出汗，脉象逐渐平静，这是因为里邪消散、表邪解除的缘故。
阳交，是指表实邪气较盛，因此脉象常呈躁动旺盛且无法出汗；并阴，起初看似阳交，但只要一出汗散热，邪气随即泄出，这是因为表邪已解、里邪轻微的缘故。
所以，“交”的病症多导致死亡，“并”的病症多能存活。《脉经》说：热病患者已经出汗，但脉象仍然躁动旺盛，这是阴脉的极端表现，主死；如果出汗后脉象平静，主生。（此处“得”字前应当有“复”字。《脉经》中记载热病烦渴后出汗，脉象应当平静。太阳病脉象反而躁动旺盛的，属于阴阳交，主死；如果再次出汗，脉象平静的，主生。又说：热病患者已经出汗，脉象仍然躁动旺盛，伴有高热，即使通过发汗治疗没有汗出，但如果出现鼻衄（流鼻血），这叫做并阳，故可活命。以上都是指再次出汗的情况。）这是将阴交与并阳结合起来论述的。
《脉经》又说：热病患者脉象常常（各版本中“常”作“尚”，是因受上文影响而误）躁动旺盛，且不能出汗的，这是阳脉的极端表现，主死；脉象躁动旺盛，但能出汗的，主生。这是将阳交与并阴结合起来论述的。
阴极和阳极，指的就是里实邪气盛和表实邪气盛的意思。大抵而言，表里俱实的病症，如果不发生“交”，就会发生“并”；如果不发生“并”，就会发生“交”。生死的关键，转变之快，犹如翻掌之间。
《史记·仓公传》中的脉法说：热病出现阴阳交的征象则死。切脉发现没有交，而是并阴。并阴的病症，脉象顺遂清静，可以痊愈。虽然热势尚未完全消退，但仍有生机。推究仓公所说的“不交”和“并阴”四个字，就知道在病情转换之间，难以预料其难易逆顺了。
诊断“交”的方法，还有进退变化的细节，各种证候详见于《脉经》。这些都是决定生死的关键诊法，务必深入探究。（再次出汗是从症状角度说的，而不是从治疗方法角度说的，所以也有经过攻下治疗后才出汗的情况。）
Yin Jiao (Yin Intersection) and Bing Yang (Bing of Yang) are diagnostic methods used to identify conditions where both the exterior (biao, 表) and interior (li, 里) aspects present with excess syndromes in febrile diseases. When both the exterior and interior are excessive and remain intermingled without clear distinction, it is termed "Jiao" (Intersection); when they gradually separate and clarify subsequently, it is termed "Bing" (Parallel/Separation).
Yin Jiao refers to a condition where interior excess is more pronounced; thus, although the patient has sweated, the pulse remains rapid and vigorous. Bing Yang initially resembles Yin Jiao, but upon subsequent sweating, the pulse gradually calms down, indicating that the interior pathogenic factor has dispersed and the exterior pathogen has been resolved.
Yang Jiao refers to a condition where exterior excess is more pronounced; thus, the pulse is often rapid and vigorous, yet no sweat is produced. Bing Yin initially resembles Yang Jiao, but once sweating occurs and heat dissipates, the pathogenic factor is immediately expelled, indicating that the exterior has been resolved and the interior excess is mild.
Therefore, cases of "Jiao" generally result in death, while cases of "Bing" generally survive. The *Mai Jing* (Pulse Classic) states: "In febrile disease, if the patient has sweated but the pulse remains rapid and vigorous, this is the extreme of Yin pulses, indicating death; if the pulse becomes calm after sweating, it indicates survival." (Note: The character "de" [obtain] should likely be preceded by "fu" [again/repeatedly]. In the *Mai Jing*, for febrile disease with irritability followed by sweating, the pulse should become calm. If the pulse in Taiyang disease is instead rapid and vigorous, it is Yin-Yang Jiao, indicating death; if sweating occurs again and the pulse becomes calm, it indicates survival. It also states: "In febrile disease, if the patient has sweated but the pulse remains rapid and vigorous, accompanied by high fever, even if diaphoresis therapy fails to produce sweat, if epistaxis [nosebleed] occurs, this is called Bing Yang, and the patient may survive." All these refer to the occurrence of repeated sweating.) This passage combines the discussion of Yin Jiao and Bing Yang.
The *Mai Jing* further states: "If the pulse in febrile disease is constantly (some editions read 'shang' [still], an error due to context) rapid and vigorous, and no sweat is produced, this is the extreme of Yang pulses, indicating death; if the pulse is rapid and vigorous but sweat is produced, it indicates survival." This passage combines the discussion of Yang Jiao and Bing Yin.
Extreme Yin and Extreme Yang refer to the states of severe interior excess and severe exterior excess, respectively. Generally speaking, in conditions where both exterior and interior are excessive, if there is no Jiao, there will be Bing; if there is no Bing, there will be Jiao. The boundary between life and death changes as quickly as flipping a hand.
The pulse method recorded in the *Shiji* (Records of the Grand Historian), Chapter on Cang Gong, states: "Febrile disease presenting with Yin-Yang Jiao results in death. Palpation reveals no Jiao, but rather Bing Yin. In Bing Yin, the pulse is smooth and clear, leading to recovery. Although the heat may not have completely subsided, the patient will live." Analyzing Cang Gong's terms "no Jiao" and "Bing Yin," one can see that the transition between these states is difficult to predict in terms of difficulty or reversibility.
The methods for diagnosing Jiao involve further nuances of progression and regression, with various syndromes detailed in the *Mai Jing*. These are essential diagnostic criteria for determining life and death and must be thoroughly studied. (The production of sweat here refers to a symptom, not a therapeutic intervention; therefore, sweat may also occur after purgative treatment.)
What is described in the *Suwen* (Basic Questions) actually pertains only to Yin Jiao and does not involve Yang Jiao. The term "Yin-Yang Jiao" is used collectively, similar to how "Yin Yi" (Yin Transformation) in men and "Yang Yi" (Yang Transformation) in women are collectively referred to as "Yin-Yang Yi."