A question about the self

The following is an excerpt from a samvaad (dialogue) session with Acharya Prashant.

Question (Q): Dear Sir, my first question is: What is Ego?

My second question is about those who lose their ‘selves’ to alcohol. Is it a neuronic activity? Can one compare this to a no-self state?

Acharya Prashant (AP): Ego is the false separation of the Self from the Whole.