Illustration/Devdutt Pattanaik

Hindus believe that knowledge ("veda" in Sanskrit) comes not from a human source, but from nature at large. This knowledge reveals itself to one who is clear in mind and pure of body. Such a person is called a rishi, which means 'one who can see what others overlook'. He transmits knowledge received through mantras or hymns. Historians, however, believe that rishis were poets (kavi), who composed the thousand-odd poems that make up the Rig Veda. People who transmitted this Vedic knowledge were called brahmins, the wisest of whom were often confused with rishis. As time passed, scholars (shastri), teachers (acharyas), mendicants (sadhu), hermits (sanyasi) and saints (sant) came to be identified as rishis. It is in later Puranic literature that they appear as supernatural beings, who travel between different realms of the cosmos, and have the power to even curse the gods.