Updated: May 17, 2021
Homeopathy was discovered and pioneered by Samuel Hahnemann, in Germany, over 200 years ago. As is still true with the use of chemical drugs, in modern medicine today, many medicines used in Hahnemann's days were toxic substances. The side effects of these substances used as medicine, such as mercury, were great. Although diluting these substances could reduce the side effects, the medicinal qualities were also lessened. Hahnemann discovered that by succussing (shaking vigorously) between dilutions, he could reduce the side effects of remedies while preserving and even enhancing their medicinal qualities. Thus, homeopathic remedies are made by succussed dilutions.
Hahnemann also proved the ancient law of like cures like, by way of experiment. He discovered that substances producing symptoms in healthy persons, when taken in excess, could cure these same symptoms in the sick. In Hahnemann's day, Cinchona, or Peruvian bark, was used in the treatment of malaria. Hahnemann took small doses of Cinchona himself and found that it produced malaria-like symptoms. Through this experiment, he proved the law of like cures like: Substances capable of producing disease symptoms in their crude form are also capable of curing these same symptoms.
By combining the law of likes cures like with the discovery of dilution and succussion, the system of healing we call homeopathy was born.