The Atman is pure consciousness, clearly manifest as underlying the states of waking, dreaming and dreamless sleep. It is inwardly experienced as unbroken consciousness, the consciousness that I AM I. It is the unchanging witness that experiences the ego, the intellect and the rest, with their various forms and changes. It is realized within one's own heart as existence, knowledge and bliss absolute, SAT CHIT ANANDA. Realize this Atman within the shrine of your own heart.

-Shankara's Viveka-Chudamani