In the ancient times, Ayurveda was learnt and taught only orally. Later on, scribes started documenting it on dried, smoothed and smoke-treated leaves of palm trees, otherwise known as Thaliolas, in order to preserve this precious wisdom for the future generations.
Ayurveda originated in the Vedic period. Believed to be the teachings of the Almighty himself, the Vedas are among the oldest records of spiritual knowledge in the world. All the four Vedas - Rig Veda, Yajur Veda, Sama Veda and Adharva Veda- have served as the basis of Indian Philosophy and have references to the principles of Ayurveda.
Rig Veda, the oldest of all Vedas, describes certain fundamental principles of Ayurveda. The three great cosmic forces namely Indra (God of Air and Prana, the vital force), Agni (God of Fire) and Soma (the Moon) represent the three main elements in Ayurveda: Vayu, Pitha and Kapha. This Veda also has over 60 preparations that could be used for healing as well as for spiritual upliftment.
Yajur Veda, describes several rituals and ceremonies which could help a person to have good health and a long life. The concepts of Dhatus (tissues) and the Pranas are also discussed in this Veda.
Basically a text concentrating on hymns, chants and verses, Sama Veda explains the therapeutic effects of chanting mantras with devotion.
Adharva Veda, the fourth book of ancient knowledge is known to have the largest number of references to Ayurveda. In fact, Ayurveda is considered to be the sub-branch or Upaveda of Adharva Veda. Ranging from medicinal values of herbs to treatment of diseases, Adharva Veda covers the essential and practical aspects of Ayurveda.
After the Vedic period, the knowledge contained in the Vedas was studied extensively, tested for correctness and compiled systematically to form Samhithas or compilations. Of these, three main Samhithas are known to have survived: Charaka Samhitha (Treatise on Medicine), Susrutha Samhitha (Treatise on Surgery) and Ashtanga Samgraha (Treatise on the basic principles). Called collectively as ‘Brihattrayi’, they are also considered to be the oldest surviving documents on Ayurveda.
Some of the famous texts written between 9th and 16th century AD include Sharangadhara Samhita (Treatise on Ayurvedic Recipes), Bhavaprakasha (History and classifications), Madhava Nidana (Treatise on Diagnosis) etc.