Samuel Hahnemann. Engraving of Samuel Hahnemann (1755-1843), a German physician who founded homeopathy. His theory was that an illness may be cured by administering minute doses of a drug which causes the same symptoms. The symptoms, he reasoned, were an effect of the body's fight against disease. During experiments on himself and his friends he found that the smaller the administered dose, the greater its effectiveness. In 1811 he published his results in Homeopathic Materia Medica. He used his methods with some success during a typhus epidemic in France in 1812. Although his results were criticised, homeopathy spread rapidly in the ensuing decades.