Schmidt Josef M
Ludwig-Maximilians-Universität München, Institut für Ethik, Geschichte und Theorie der Medizin, München.
Med Ges Gesch. 2010;29:151-84.
The principle of similars (treat likes by likes) is generally considered to be one of the pillars of the homeopathic doctrine established by Samuel Hahnemann (1755-1843). Nevertheless, its status and relevance with regard to the practice of homeopathy can be challenged by semantic, conceptual, and epistemological objections. 1. Contrary to its literal meaning, "similia similibus curentur" is commonly used in the sense of "all diseases should be treated by similar drug diseases", thus transgressing its original field of indication. 2. From 1796, when Hahnemann published his first definition of the principle of similars, he gradually raised his claims from merely suggesting a heuristic principle for finding new curative remedies to insisting on having discovered a law of nature and the only true way of healing, in 1807/1808. To substantiate his ambitious tenets, Hahnemann had to introduce a variety of theories which in turn were to become the main battleground in the ensuing controversy about homeopathy. 3. From the perspective of epistemology of science, science can never consist of a final set of absolute truths or the like but must rather be described as a continuous social process that retains a methodological cycle of abduction, deduction, and induction. From the perspective of theory of medicine, however, medicine is to be considered as a practical rather than a cognitive science in its own right. Its first concern ought to be the development of practical directions for treating patients, while the value of competing theories can only be judged from their usefulness in practice. Hence, even though Hahnemann's theories, including his conception of the principle of similars, may be untenable or outdated, the genuine method of homeopathic treatment he founded remains independent of and unaffected by criticism at the level of theory and concepts.
同类疗法原则（以类治类）通常被认为是塞缪尔·哈内曼（1755 - 1843）所创立的顺势疗法学说的支柱之一。然而，其在顺势疗法实践中的地位和相关性可能会受到语义、概念和认识论方面的质疑。1. 与字面意思相反，“以类治类”通常被理解为“所有疾病都应由类似的药物疾病来治疗”，从而超越了其最初的适用范围。2. 从1796年哈内曼首次发表同类疗法原则的定义开始，他逐渐提高了自己的主张，从仅仅提出一种寻找新治疗药物的启发式原则，到1807/1808年坚持认为自己发现了一条自然法则和唯一真正的治愈方法。为了证实他雄心勃勃的信条，哈内曼不得不引入各种理论，而这些理论反过来又成为了随后关于顺势疗法的争论的主要战场。3. 从科学认识论的角度来看，科学绝不可能由一组最终的绝对真理之类的东西构成，而更应该被描述为一个持续的社会过程，这个过程保留了一个包括溯因、演绎和归纳的方法论循环。然而，从医学理论的角度来看，医学本身应被视为一门实践科学而非认知科学。它首要关注的应该是为治疗患者制定实践指南，而相互竞争的理论的价值只能从它们在实践中的有用性来判断。因此，尽管哈内曼的理论，包括他的同类疗法原则概念，可能站不住脚或过时了，但他创立的真正的顺势疗法治疗方法仍然独立于理论和概念层面的批评，且不受其影响。
