Sun Simiao on animal-derived ingredients in medicines
Chinese herbal medicines are well-known for often containing rare animal ingredients like tiger bone. In my opinion, a lot of this probably originated more from social/political pressure to make remedies for the Emperor or nobility from rare ingredients than from any increase in efficacy over plant materials, but regardless of the origin it's a common feature of Chinese herbal formulas, and most practitioners seem to accept it without question.
So I was pleased to stumble on this excerpt from the work of Sun Simiao. Sun was a Tang dynasty physician born around 581; he wrote the classic herbalism treatise Prescriptions for Emergencies Worth a Thousand Gold and is so highly regarded in the history of Chinese medicine that he has been worshiped as the "King of Medicine". He wrote:
From early times famous persons frequently used certain living creatures for the treatment of diseases, in order to thus help others in situations of need. To be sure, it is said: "Little esteem for the beast and high esteem for man," but when love of life is concerned, man and animal are equal. If one's cattle are mistreated, no use can be expected from it; object and sentiments suffer equally. How much more applicable is this to man!
Whoever destroys life in order to save life places life at an even greater distance. This is my good reason for the fact that I do not suggest the use of any living creature as medicament in the present collection of prescriptions.