This had its genesis in the ancient Hindu scriptures - the Vedas, the Upanishads and the Bhagavad Gita - and went on to blossom in the minds of some of the greatest American writers of the 19th century - Ralph Waldo Emerson, William James, Herman Melville, Walt Whitman, Henry David Thoreau and many others.
Great minds, such as these, were relentlessly tortured by the differences between two seemingly disparate areas of human endeavour, namely, the spiritual consciousness (Purush) and the reality of existence (Prakrit). Unable to resolve the rift they eventually turned to Hinduism and found the answer in Chapter XIII verse 24 of the Bhagavad Gita:
"Dhyaanaynaatmani pashyanti kaychidaatmaanama atmanaa". This means that meditation refines the intellect and expands it to realize the supreme spirit that dwells in every being. It is meditation which can lift us from the mundane existence (Prakrit) to attain one's true self (Purush) or the inner consciousness which is nothing but the manifestation of the Divine self.