Ayurveda is the most ancient indigenous medical system of India. The term Ayus means duration or span of life, veda means unimpeachable knowledge. The common translation of the Ayurveda is 'science of life'. The tradition says that Brahma (the creator) was the divine source of this science, which was brought into existence before the creation of mankind. The knowledge passed from him to the god Daksapati, then to the two celestial physicians (the twin Asvina Kumaras), later to Indra the god king, and finally to Bharadvaja, the semi-divine sage. The earliest recorded knowledge about Ayurveda is found in the Rigveda and the Atharaveda, probably of the second millennium BC. But the proper knowledge of this ancient science comes mainly from some written treatises, the oldest of which are the samhitas named Bhela, Charaka and Susruta. Charaka's original was the samhita of Agnivesa, a disciple of the sage Atreya. Long passages in the Charaka Samhita are in the form of questions and answers between Atreya and Agnivesa. Chakrapani Datta in his Ayurvedadipika referred to this original Agnivesa Samhita even so late as the 11th century AD. Charaka is a class title of a school of physicians, existing from Vedic times and also the personal title of a physician in the court of king Kanishka, and possibly the title of many other physicians belonging to the same school of medicine.
In the book named History of Science in India, Debiprasad Chattopadhyaya writes an interesting article on Ayurveda with special reference to Charaka Samhita (See the reference given below). According to Chattopadhayaya, Charak Sanhita gives not only many examples of flat contradictions in the text, but also shows how to explain the contradictions and avoid the fallacy of taking everything embodied in the text as representing the genuine standpoint of ancient Indian medicine.
Indian medical system has the great treatments for many incurable diseases. The Charaka and Susruta Samhitas mention eight different branches of medical knowledge. The former is an exhaustive work on the first branch (therapeutic medicine) only; though it contains many sections dealing with surgery and the other six branches. It deals mainly with anatomy, physiology, aetiology and prognosis, pathology, treatment, objectives and influence of environmental factors, medicine and appliances and procedure and sequence of medication.
Charaka Samhita is an important work on medicine. Charaka Samhita divides the animals and its flesh in various categories. According to the Samhita's physician's view the body is the product of food; disease is born of food; the distinction between happiness and sorrow is based upon the difference between wholesome and unwholesome diet. Charaka Samhita prescribes even flesh for the disorders caused by an excess of vayu, rhinitis, irregular fever, dry cough, fatigue and also in cases of excessive appetite. It is interesting to note that the Western science has discovered the value of wine only recently but Charaka Samhita already shows that it is aware of its good qualities. It mentions that wine is a product of various substances and possesses many qualities. It says that if a person drinks it in right time, in right manner, in right dose with some food then it acts like ambrosia in body. The Samhita does however recognise alcoholism as a morbid condition.
Direct observation is the most remarkable feature of Ayurveda, though at times it is mixed up with metaphysics. The Samhita emphasises that of all types of evidences the most dependable ones are those that are directly observed by the eyes. In Ayurveda successful medical treatment crucially depends on four factors: the physician, substances (drugs or diets), nurse and patient. The qualifications of physician are: clear grasp of the theoretical content of the science, a wide range of experience, practical skill and cleanliness; qualities of drugs or substances are: abundance, applicability, multiple use and richness in efficacy; qualifications of the nursing attendant are: knowledge of nursing techniques, practical skill, attachment for the patient and cleanliness; and the essential qualifications of the patients are: good memory, obedience to the instructions of the doctors, courage and ability to describe the symptoms.
Ayurveda is remarkable for its special conceptions and theories. It must be emphasized that the curing of diseased conditions and the maintenance of health are not the only aims of Ayurveda but it is also concerned with harmonizing secular conduct and spiritual pursuit through a realization of the true relationship between the complex of body, mind and soul and the external universe.
Chattopadhyaya, D. 1982. Case for a critical analysis of the Charak Samhita. In Studies in the History of Science in India (Ed. D. Chattopadhyaya). Vol. 1. New Delhi: Editorial Enterprises. Pp. 209-236.