The rishis heard the Veda and saw its structure, and this sound itself is expressed in the hymns of the Rig Veda.
The Rig Veda was not “created” out the human imagination, as works of poetry or literature are created.
Unlike poetry or literature, the Veda is experienced and then the experience of the Veda is recited in hymns that directly express the experience of the Veda. Cognition means that the Vedic rishis or seers heard what is there in the universal field of consciousness and they sang out the sounds that they heard.
This experience is what the recited sounds of the Veda express.
But the hymns of the Rig Veda are not about the Veda, as if the expression were something different from the Veda itself, which they were describing.
These four bodies of sound are what is meant by the Veda.
In addition to the Veda, the Vedic literature includes 36 branches, all based on the Veda itself : six branches of Vedanga, six branches of Upanga, and six branches of Ayur-Veda, for example.All branches of Vedic literature are considered, like the Veda itself, uncreated or eternal structures of knowledge.By two pundits chanting the hymns (and by chanting them forwards and backwards), a method of ensuring their purity was established that allowed these hymns to be passed on over thousands of years without loss.The Veda we possess today, unbelievable as it may seem, is thus an expression of the sounds heard many thousands of years ago.There are at least 40 distinct branches of the Veda and the Vedic literature.These include, first and foremost, the Rig Veda samhita, and the Sama Veda, Yajur Veda, and Atharva Veda.