was developed by Dr Samuel Hahnemann (1755-1843) starting with his recognition of the Law of Simila as a general therapeutic law. Although people like Hippocrates and Paracelsus (born around 1493), had proposed & used similar ideas in their times, it was Dr. Hahnemann who first recognised & applied this therapeutic principle as a general law.
In the 18th century, the medical science was still very unscientific. The knowledge about human body, diseases and the modalities of treatment were poor and vague. Methods like blood-letting, leeching, purging were the common treatments for most ailments. Practically the whole of the 18th century in Europe was marked by a plethora of theories and hypothesis concerning the nature of disease and its causation. Consequently methods of therapeutic practice were as numerous and diverse as the theories propounded. The uncertainty and lack of any fixed principle of healing disappointed Dr. Hahnemann. read more at http://hpathy.com/abc-homeopathy/what-is-homeopathy-2/