The most charitable explanation I heard was that homeopathy was developed in an era when insanely toxic substances like mercury salts were regularly used as med

The most charitable explanation I heard was that homeopathy was developed in an era when insanely toxic substances like mercury salts were regularly used as medicine. Someone noticed that using “less concentrated medicine” resulted in healthier patients. Then obviously even less concentrated medicine “worked” better, and so on… You can easily see how a simple logical extrapolation from there would result in ardent believers of homeopathy. (To make matters worse: Simply hydrating patients with water is a fairly effective treatment all by itself!)