Svetaketu Upanishad

 “Fetch me a fruit of the banyan tree.”

“Here is one, sir.”
“Break it.”
“I have broken it, sir.”
‘What do you see?”
“very tiny seeds, sir.”
“Break one.”
“I have broken it, sir.”
“Now what do you see?”
“Nothing, sir.”
“My son,” the father said, “ what you do no perceive is the essence, and in that essence the mighty banyan tree exists. Believe me, my son, in that essence is the self of all that is. That is the Truth, that is the Self. And you are that Self, Svetaketu!”