Non-duality is not oneness

यस्मिन्सर्वाणि भूतान्यात्मैवाभूद्विजानतः। तत्र को मोहः कः शोक एकत्वमनुपश्यतः ॥ ७ ॥

yasminsarvāṇi bhūtānyātmaivābhūdvijānataḥ | tatra ko mohaḥ kaḥ śoka ekatvamanupaśyataḥ || 7 ||

When to the man of realization all beings become the very Self, then what delusion and what sorrow can there be for that seer of oneness? (Or — In the Self, of the man of realization, in which all beings become the Self, what delusion and what sorrow can remain for that seer of oneness?) -Ishavasya Upanishad

Acharya Prashant: To begin with oneness in the absolute sense cannot be seen. Remember here, as we have said multiple times tonight, that the objective of the verses is to educate the mind. So, when the word ‘oneness’ is being used, it is being used in a sense that will be beneficial to the mind.

The mind cannot experience absolute oneness because the mind operates in duality. All experience requires the experienced object to carry a background of its opposite. On a white wall, you will perceive nothing if it is marked with white. You cannot write with a white marker on a whiteboard.

Experience necessitates two, for one to be perceived, the second has to keep lurking in the background. Absolute oneness means the object of perception, and its background, and the perceiver, have all become one. Now how can there be any…