寻万物之性，皆有离合，虎啸风生，龙吟云起，磁石引针，琥珀拾芥，漆得蟹而散，麻
得漆而涌，桂得葱而软，树得桂而枯，戎盐累卵，獭胆分杯。其气爽有相关感，多如此类。
其理不可得而思之。至于诸药，尤能递为利害。先圣既明言其说，何可不详而避之。世人为
方，皆多漏略。若旧方已有，此病亦应改除。假令而两种，当就其轻重，择可除而除之。伤
寒赤散，吾恒不用藜芦。断下黄连丸，亦去其干姜而施之，殆无不效。何急强以相增，苟令
共事乎？相反为害，深于相恶。相恶者，谓彼虽恶我，我无忿心，犹如牛黄恶龙骨，而龙骨
得牛黄更良，此有以相制伏故也。相反者，则彼我交仇，必不宜合。今画家用雌黄、胡粉相
近，便自黯妒。粉得黄即黑，黄得粉亦变，此盖相反之征。药理既昧，所以人多轻之。今案
方处治，恐不必卒能寻究本草，更复抄出其事在此，览略看之，易可知验。而《本经》有直
云茱萸、门冬者，无以辨其山、吴、天、麦之异，咸宜各题其条。又有乱误处，譬如海蛤之
与鳝甲，畏恶正同。又诸芝使薯蓣，薯蓣复使紫芝。计无应如此，而不知何者是非？亦宜并
记，当更广检正之。又《神农本经》相使，止各一种，兼以《药对》参之，乃有两三，于事
亦无嫌。其有云相得共治某病者，既非妨避之禁，不复疏出。
考察万物的本性，都有相互结合或排斥的现象。老虎咆哮则风生，龙吟叫则云起，磁石能吸引铁针，琥珀能吸附芥子末；漆遇到螃蟹就会消散，麻遇到漆就会涌出（指变质或反应），桂枝遇到葱就会变软，树木遇到桂枝就会枯死，戎盐可以堆叠如卵，獭胆可以将一杯酒分为两半。它们之间气息清爽且相互感应，大多如此类情况。其中的道理难以用思维去穷尽。至于各种药物，尤其能够互相产生利害影响。先圣已经明确说明了这些说法，怎么能不详细查看并加以避免呢？世人配制药方，大多疏漏简略。如果旧有的药方中已有禁忌，此病证也应当修改去除。假设有两种药物存在禁忌，应当根据病情的轻重，选择可以去除的药物而去除它。治疗伤寒的赤散方，我通常不使用藜芦。治疗痢疾的黄连丸，也去掉干姜而使用，几乎无不奏效。何必急于强行增加药物，苟且让它们共同使用呢？相反产生的危害，深于相恶。所谓相恶，是指虽然彼此厌恶，但我没有怨恨之心，就像牛黄厌恶龙骨，但龙骨得到牛黄反而更好，这是因为有相互制约的原因。所谓相反，则是彼此如同仇敌，一定不宜合用。如今画家用雌黄、胡粉相近放置，便自然相互暗妒。粉末遇到雄黄就变黑，雄黄遇到粉末也会变色，这大概是相反的征兆。药理既然晦涩不明，所以人们大多轻视它。现在审查处方用药，恐怕不必立刻能深入研究本草，再次抄录这些事情在此处，粗略阅读一下，容易知道验证。而《本经》中有直接说茱萸、门冬的，无法辨别是山茱萸、吴茱萸、天冬、麦冬的区别，都应当在各条目下注明。又有混乱错误的地方，比如海蛤与鳝甲，畏恶关系完全相同。又有各种灵芝使薯蓣，薯蓣又使紫芝。估计不应该如此，但不知道哪个是对的哪个是错的？也应该一并记录，应当再广泛检查纠正。另外《神农本经》中的相使，每种只有一种，兼以《药对》参考，就有两三种，对于事情也没有嫌疑。其中有说相得共同治疗某病的，既然不是妨碍回避的禁忌，就不再罗列出来。
Examining the nature of all things, there are always interactions of combination and separation. When a tiger roars, wind arises; when a dragon chants, clouds rise; magnetite attracts iron needles; succinite picks up mustard seeds. Lacquer disperses upon contact with crab; hemp reacts violently (swells/ferments) upon contact with lacquer; cinnamon twig becomes soft when combined with green onion; trees wither when exposed to cinnamon twig; rock salt can be piled like eggs; otter gallbladder bile can divide a cup of wine in two. Their qi is clear and mutually responsive, mostly following such patterns. The underlying principles are beyond full comprehension by thought. As for various medicinal substances, they particularly influence each other through mutual benefit or harm. The Sages have already clearly stated these principles; how can one fail to examine them in detail and avoid the harms? People formulating prescriptions today are often negligent and omitting details. If an old prescription contains contraindications, it should be modified and those elements removed. Assuming there are two substances with incompatibilities, one should judge based on the severity of the condition and remove the less essential substance. In the Chisan Decoction for treating Cold Damage, I usually do not use Veratrum Viride Rhizome (Lilü). In the Coptis Pill for stopping dysentery, I also remove Dried Ginger (Ganjiang) and use it instead, achieving almost invariably effective results. Why rush to forcibly add substances and allow them to coexist despite incompatibilities? The harm caused by "mutual opposition" (Xiangfan) is deeper than that of "mutual aversion" (Xiang'e). Mutual aversion means that although they dislike each other, there is no hostility; for example, Niuhuang (Calculus Bovis) dislikes Gulong (Os Draconis), yet Gulong becomes more efficacious with Niuhuang, because one restrains the other. Mutual opposition means they are like enemies and must not be combined. Today, painters place Realgar (Yinghuang) and Lead White (Hufen) near each other, and they naturally darken and spoil one another. Powder turns black when mixed with Realgar, and Realgar changes color when mixed with powder; this is a sign of mutual opposition. Since pharmacological principles are obscure, people tend to轻视 (disregard) them. Now, reviewing prescriptions, one may not immediately be able to investigate the Bencao extensively; thus, I copy these matters here for reference. A brief reading makes verification easy. However, the *Shennong Benjing* directly mentions Zhuyu (Cornus Fruit) and Mendong (Ophiopogon Tuber) without distinguishing between Shan Zhuyu (Mountain Cornus), Wu Zhuyu (Evodia Fruit), Tian Dong (Asparagus Tuber), and Mai Dong (Ophiopogon Tuber); each entry should specify its type. There are also confused errors, such as Haige (Concha Arcae) and Shanjia (Testudo Shell), which have identical mutual aversions. Also, various Zhi (Ganoderma) utilize Shuyao (Dioscorea Hypoglauca Rhizome), and Shuyao utilizes Zizhi (Purple Ganoderma). It is unlikely this is correct, but it is unknown which is right or wrong; these should be recorded together and further checked for correction. Furthermore, the *Shennong Benjing* lists only one "mutual enhancement" (Xiangshi) per substance; consulting the *Yaodui*, there are two or three. This does not cause objection. Those entries stating that substances "mutually agree" (Xiangde) to treat specific diseases are not forbidden combinations, so they are not listed separately.