Khandogya-Upanishad: Eighth Prapathaka, Twelfth Khanda

2. “The wind is without body, the cloud, lightning, and thunder are without body (without hands, feet, &c.) Now as these, arising from this heavenly ether (space), appear in their own form, as soon as they have approached the highest light,

3. “Thus does that serene being, arising from this body, appear in its own form, as soon as it has approached the highest light (the knowledge of Self). He (in that state) is the highest person (uttama purusha). He moves about there laughing (or eating), playing, and rejoicing (in his mind), be it with women, carriages, or relatives, never minding that body into which he was born.

“Like as a horse attached to a cart, so is the spirit (prâna, pragnatman) attached to this body.

4. “Now where the sight has entered into the void (the open space, the black pupil of the eye), there is the person of the eye, the eye itself is the instrument of seeing. He who knows, let me smell this, he is the Self, the nose is the instrument of smelling. He who knows, let me say this, he is the Self, the tongue is the instrument of saying. He who knows, let me hear this, he is the Self, the ear is the instrument of hearing.

5. “He who knows, let me think this, he is the Self, the mind is his divine eye. He, the Self, seeing these pleasures (which to others are hidden like a buried treasure of gold) through his divine eye, i.e. the mind, rejoices.

“The Devas who are in the world of Brahman meditate on that Self (as taught by Pragâpati to Indra, and by Indra to the Devas). Therefore all worlds belong to them, and all desires. He who knows that Self and understands it, obtains all worlds and all desires.” Thus said Pragâpati, yea, thus said Pragâpati.