On the Self in the body - Kena Upanishad

The student inquires:
"Who makes my mind think?
Who fills my body with vitality?
Who causes my tongue to speak? Who is that
Invisible one who sees through my eyes
And hears through my ears?"

The teacher replies:
"The Self is the ear of the ear,
The eye of the eye, the mind of the mind,
The word of words, and the life of life.
Rising above the senses and the mind
And renouncing separate existence,
The wise realize the deathless Self."

-Kena Upanishad