Homoeopathy" was introduced as a medical system of drug therapeutics by a German Physician, Dr. Samuel Hahnemann in 1805. While translating a medical treatise of Scottish physician and chemist, William Cullen, from English to German, in 1790, Dr Hahnemann came across a foot note under Cinchona that attributed its fever curing property to the astringent (decongestant) qualities of the drug. Being skeptical of Cullen's remarks concerning the effect of Cinchona for curing malaria, Hahnemann experimented its effect on himself by taking repeated doses of cinchona tincture. He experienced fever, shivering and joint pains: symptoms similar to those of malarial fever. After series of experiments, Hahnemann concluded that a drug that could produce certain symptoms in healthy individuals could also cure similar disease symptoms of natural diseases. This was in accordance with some hidden, natural laws of similars as had been vaguely perceived by ancient physicians. This led to the coining of the word "homoeopathy"
Hahnemann postulated the key principle of Homoeopathy
The Law of Similar
It is also called the Law of Cure. This law demonstrates that the selected remedy is able to produce a range of symptoms in healthy persons similar to that observed in the patients. Based on his experiments, Hahnemann published this law in an article “Essay on New Principle for Ascertaining the Curative Powers of Drugs” in Huffland’s Journal in 1796. This law is the principle of Similia Similibus Curentur i.e. let likes be treated by likes. Law of Similar teaches that every homoeopathic remedy experimentally observed to have certain properties of producing a set of symptoms on healthy human beings and when these symptoms matches with a natural disease, it act as therapeutic agent and help the body to correct the disorder. As per this concept, the symptoms produced by the substance during the drug proving are the signature of that drug. Therefore, in strict sense, this signature of the drug is the one and only one that qualify into the principle of Similia Similbus Curentur. This is the most important concept in Homoeopathy. In fact there cannot be any concept in homoeopathy without this key concept.
In Homeopathy, remedies are selected on the basis of Totality of symptom. The most appropriate remedy suitable to the patient is called similimum.