祸由之法，《内经》贼风篇，岐伯曰∶先巫知百病之胜，先知其病所从生者，可祸而已
也。
又移精变气论，岐伯云∶古恬淡世，邪不能深入，故可移精祸由而已。今人虚邪贼风，内着
五脏骨髓，外伤空窍肌肤，所以小病必甚，大病必死，故祸由不能已也。由此观之，则祸由
之法，亦不过因其病情之所由，而宣意志气，以释疑而解惑。此亦必病之轻者，或有感应之
理。若果病机病重，亦不能有效也。古法今已不传，近所传符咒之术，间有小效；而病之大
者，全不见功。盖岐伯之时已然，况后世哉？存而不论可也。
禽兽之病，由于七情者少，由于风寒饮食者多，故治法较之人为尤易。夫禽兽之脏腑经
络，
虽与人殊，其受天地之血气，不甚相远，故其用药亦与人大略相同。但其气粗血浊，其所饮
食，非人之饮食，则药亦当别有主治，不得尽以治人者治之矣。如牛马之食，则当用消草之
药；犬豕之食，则当用消糠豆之药是也。又有专属之品，如猫宜乌药，马宜黄药之类。而其
病亦一兽有一兽独患之病，此则另有专方主治。余则与人大段相同。但必剂大而力浓之方，
取效为易。其中又有天运时气之不同，变化多端，亦必随证加减。此理亦广博深奥，与治人
之术，不相上下。今则医人之医尚绝传，况兽医乎？
关于祝由科治病的方法，《黄帝内经·贼风篇》中，岐伯说：以前的巫师知道各种疾病可以克制的方法，预先知道疾病产生的根源，就可以通过祝由来治愈了。
又在《移精变气论》中，岐伯说：在远古恬淡无欲的时代，邪气不能深入体内，所以可以通过移精变气、祝由的方法来治疗。现在的人受到虚邪贼风的侵袭，邪气内侵五脏骨髓，外伤孔窍肌肤，所以小病一定会加重，大病一定会死亡，因此祝由法就不能治愈疾病了。由此看来，祝由这种方法，也不过是根据病情产生的原因，疏导患者的意志和气机，以解除疑虑和困惑。这也只有在病情较轻时，或许有一定的感应道理。如果确实是病机复杂或病情严重，也不能见效。古法现在已经失传，近代流传的符咒之术，偶尔有小效；但对于大病，完全看不到效果。这在岐伯那个时代就已经如此，何况后世呢？保留而不讨论就可以了。
禽兽的疾病，由于七情（喜、怒、忧、思、悲、恐、惊）引起的较少，由于风寒饮食引起的较多，所以治疗方法比治疗人更容易。禽兽的脏腑经络，虽然与人不同，但它们承受天地的血气，与人大致相近，所以用药也与人大致相同。但是它们的体质粗犷、血液浑浊，所吃的食物不是人的食物，所以药物也应当有专门的主治功能，不能全部用治疗人的方法来治疗它们。比如牛马吃的草料，就应当使用消食化草的药物；狗猪吃的糠豆，就应当使用消食化糠豆的药物。又有专门针对某种动物的药材，比如猫适宜用乌药，马适宜用黄药之类。而且每种动物也有各自单独患有的疾病，这则有另外专门的方剂主治。其余情况则与人大致相同。但必须使用剂量大、药力浓的方剂，才容易取得疗效。其中又有天时运气气候的不同，变化多端，也必须根据症状进行加减调整。这个道理也是广博深奥的，与治疗人的医术不相上下。现在连给人看病的医生都几乎断绝传承，何况兽医呢？
Regarding the method of treating diseases through *Zhuyou* (incantation and ritual), in the "Zeifeng" (Thief Wind) chapter of the *Huangdi Neijing* (Yellow Emperor's Inner Canon), Qibo stated: Ancient shamans knew how to overcome various diseases; by first knowing the origin from which the disease arises, one could cure it through Zhuyou.
In the "Yijing Bianqi" (Transfining Spirit and Changing Qi) chapter, Qibo said: In ancient times when people were tranquil and indifferent, pathogenic factors could not penetrate deeply, so diseases could be treated by transferring spirit and altering qi through Zhuyou. Nowadays, people are affected by deficient evils and thief winds, which lodge internally in the five zang organs and bone marrow, and externally injure orifices, skin, and muscles. Therefore, minor illnesses inevitably become severe, and major illnesses inevitably lead to death; thus, Zhuyou cannot cure them. From this perspective, the method of Zhuyou is merely to guide the patient's will and qi according to the origin of the condition, thereby dispelling doubts and resolving confusion. This may have some efficacy based on spiritual resonance only when the illness is mild. If the pathological mechanism is complex or the illness is severe, it will certainly not be effective. The ancient methods are no longer transmitted today. The talismanic and incantatory arts circulated recently occasionally show slight effects, but for serious illnesses, they produce no results at all. This was already the case in Qibo's time, let alone in later generations. It is acceptable to preserve the records without further discussion.
The diseases of birds and beasts arise less often from the seven emotions (joy, anger, worry, thought, sadness, fear, and fright) and more often from wind-cold and dietary factors; therefore, treatment methods are easier than those for humans. Although the zang-fu organs and meridians of animals differ from those of humans, their reception of heaven-earth blood and qi is not significantly distant, so their medication is roughly similar to that used for humans. However, their constitution is coarse and their blood turbid, and their diet differs from human food; therefore, drugs must have specific indications and cannot simply use human treatments for animals. For example, since cattle and horses eat grass, herbs that digest grass should be used; since dogs and pigs eat bran and beans, herbs that digest bran and beans should be used. There are also specific substances exclusive to certain animals, such as Wuyao (Linderae Radix) being suitable for cats, and Huangyao (likely referring to a specific herb like Sophorae Flavescentis Radix or similar context-dependent term) being suitable for horses. Furthermore, each species has unique diseases peculiar to itself, which require specific formulas for treatment. Other aspects are largely similar to human medicine. However, larger dosages and stronger formulations are necessary to achieve efficacy easily. Additionally, variations in seasonal climate and qi cause diverse changes, requiring modifications based on symptoms. This principle is broad, profound, and comparable to the art of treating humans. Today, even physicians treating humans are nearly extinct, let alone veterinarians.