gaudapada, in his karika on the mandukya upanishad, refers to the three states of consciousness, to the one atman perceived threefold in the same body and the threefold satisfaction; he refers to vaisvanara – जागरितस्थानो बहिष्प्रज्ञः whose sphere of action is the waking state, to taijasa – स्वप्नास्थानोऽन्तःप्रज्ञः whose sphere is the dream state, and to "prājna" (प्राज्ञ), whose sphere in the form of cause only is deep sleep bereft of dreams, as a mass of consciousness, as the akasha in the heart and as the blissful one. he states that 'dream' is the wrong apprehension of reality, 'sleep' is the state in which one does not know what reality is; when the false experience in these two states disappears turiya is realized (gaudapada karika i.vii.15). and, yajnavalkya in brihadaranyaka upanishad advises that the intelligent seeker of brahman, learning about the self alone, should practice wisdom ("prajñā") and not think of too many words, for that is exhausting to the organ of speech.