At the turn of the 18th Century, a German doctor quit his practice for the same reason that modern doctors are frustrated by medicine. He saw that by giving the strong doses of herbs and minerals to the sick was causing more disease than he was healed. We know that he was a man of principle because although he had many children to feed, but he stopped practicing medicine and turned to translating the herbal and medical textsbooks of the day to earn his living. He was translating the textbook of a famous herbalist and noticed that the text said the herb was bitter and that was why it cured. Hahnemann did not like empty claims so he boiled the herb and drank a medicinal dose.
This was the first test of the homeopathic principle that likes cure likes. Although he was perfectly healthy, he immediately developed the symptoms of malaria. As a practicing doctor, he had used China on patients with malarial fevers many times before. How odd, he thought, I am healthy, but I am experiencing the symptoms that this herb is supposed to cure: the symptoms of malaria. As if he had malaria, he quickly developed a fever that came and went in cycles. He was experiencing one of the important symptoms of the homeopathic remedy, China. This experience started him in his life long investigation of the priniciple that remedies which will cause symptoms in the healthy person will cure those same symptom in a sick person.