Hippocrates (460 – 370 BC), who is considered as the father of medicine postulated two principles of treating diseases, one is Contraria Contrariis Curantur (Latin) which means opposites are cured by opposites. This principle teaches to treat disease by using remedies that produce opposite effects. The other principle is the Similia Similibus Curentur (Latin), which means let similar things take care of similar things. Hippocrates was known to have said, "Through the like, disease is produced, and through the application of the like it is cured." This is now commonly known as similia principle. For Hippocrates, any medical intervention should be aimed to establish a treatment covering the whole human being, both physical and mental sphere and its relationship with the environment, but individualizing process. "There are no diseases but sick," he said. Similar concepts are found in the Indian traditional medical system- Ayurveda.
Later, the Swiss alchemist Paracelsus (1493- 1541) employed the similia principle on healing illnesses. However, it was the German doctor, Dr. Christian Friedrich Samuel Hahnemann (1755 - 1843) who examined this principle thoroughly and codified the fundamental principles of what was to become Homeopathy. Dr Hahnemann was disatisfied by the medical practices of that time. Therefore, he made efforts to develop a method of healing which would be safe, gentle, and effective. He believed that human beings have an innate capacity for healing themselves and that the symptoms of disease reflect the individuals struggle to overcome his illness.
While translating Cullen’s Materia Medica from English to German, Hahnemann was not convinced over the theoretical explanation of the fever curing property of ‘Cinchona bark’ attributed to its astringent properties. He noted that there were plenty of other drugs with the same property, which did not possess fever-curing capabilities. He conducted experiments upon himself which went down in history, known as the famous “Peruvian bark Trial’. After series of tests, Hahnemann observed an effect which resembled malarial fever. Following this clue, he started to prove several drugs on himself and other healthy volunteers. In every case, he noticed the similarity of symptoms produced by the drugs that it could cure in natural diseases.
Hahnemann continued to experiment, noting that every substance he took, whether a herb, a mineral, an animal product or a chemical compound, produced definite distinct symptoms in him. He further noted that no two substances produced exactly the same set of symptoms. Furthermore the symptoms were not just confined to the physical plane,every substance tested also affected the mind and the emotions.
Eventually, Hahnemann began to treat the sick on the principle ‘let likes be treated by likes’. From the outset he achieved outstanding clinical success.