The conversation between father Uddalaka and son Svetaketu, as narrated in Chandogya Upanisad.
As was the customary in those days, Svetaketu was sent to an ashram for his education and when he returned after the completion, Uddalaka asked him, “What did you learn while in the Ashram, my son?”
“I learned everything that can be known, father,” Svetaketu answered .
When Uddalaka heard this, he became silent and thought, “What pride! Such conceit is born only out of ignorance. My son has not yet grasped the essence of the supreme knowledge of Atman which brings humility.”
He asked Svetaketu to fetch a fruit of the Nyagrodha tree. Shvetketu picked a fruit from the tree and brought it to his father.
“Break it, son, and look inside,” suggested Uddalaka.
“What do you see?” Uddalaka questioned.
“These extremely fine seeds, father,” replied Svetaketu.
“Of these, please break one and what you see inside?” asked Uddalaka.
“No! There is nothing there” responded Svetaketu.
Then Uddalaka said to his son, “My dear, that subtle essence which you do not perceive, from that very essence this great Nyagrodha tree exists. That, Svetaketu, is the Atman, that subtle essence, this whole world has for its self. That is the truth. The Atman pervades the universe, and, my son, you are a part of that universe.”
Uddalaka explains how the world which has the name and form arises from Pure Being which is subtle and doesn’t possess name and form .
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