praśnopaniṣad - caturthaḥ praśnaḥ

The Fourth Question: Then Gargya, of the lineage of Surya, asked him: "Lord, what are the entities that sleep in this human person? What are the entities that remain awake? Which is the divine being who experiences dreams? To whom does this happiness belong? And in whom are all these established?"

He replied to him: "Just as, O Gargya, when the sun sets, all its rays become unified in this solar orb, and they spread out again when it rises, so indeed does all this become unified in the Supreme Divine, the mind. Therefore, at that time, this person does not hear, does not see, does not smell, does not taste, does not touch, does not speak, does not grasp, does not enjoy, does not release, and does not move. They say, 'He is sleeping.'"

"The fires of the vital forces (Pranas) alone remain awake in this city (the body). The Apana is the Garhapatya fire; the Vyana is the Anvaharyapacana fire; and since the Prana is led forward from the Garhapatya fire, it is the Ahavaniya fire."

"The Samana is so called because it carries equally the two offerings—inhalation and exhalation. The mind is the sacrificer. The Udana is the fruit of the sacrifice, which leads this sacrificer daily to Brahman."

"In this state, the divine being experiences his own greatness in dreams. Whatever has been seen, he sees again; whatever has been heard, he hears again; whatever has been experienced in different regions and directions, he experiences again and again. He sees both the seen and the unseen, the heard and the unheard, the experienced and the unexperienced, the real and the unreal; he sees all, for he is everything."

"When he is overpowered by the inner light (Tejas), then this divine being does not see dreams; at that time, this happiness arises within this body."

"Just as, O beloved one, birds fly toward the tree that is their dwelling place, so does all this rest in the Supreme Self."

"The earth and its subtle elements, water and its subtle elements, light and its subtle elements, air and its subtle elements, space and its subtle elements; the eye and what is seen, the ear and what is heard, the nose and what is smelled, the tongue and what is tasted, the skin and what is touched, the organ of speech and what is spoken, the hands and what is grasped, the generative organ and what is enjoyed, the anus and what is excreted, the feet and what is walked upon, the mind and what is thought, the intellect and what is understood, the ego and what is identified, the heart (citta) and what is perceived, the light (tejas) and what is illuminated, the vital breath (prana) and what is sustained."

"Verily, this is the seer, the toucher, the hearer, the smeller, the taster, the thinker, the knower, the doer—the conscious self, the Person. He rests in the Supreme, Imperishable Self."

"He who knows that Imperishable, which is shadowless, bodiless, colorless, and pure, attains the Supreme Imperishable alone. He, O beloved one, who knows this becomes all-knowing and becomes the All. Regarding this, there is this verse."

He who knows that Imperishable Brahman, wherein the cognizing self, along with all the senses, the vital breaths, and the elements find their resting place—he, O gentle one, becomes all-knowing and has entered into everything.