How can one be certain when one leave the external world--when the person is within the world?
Why leave the external world when everything is Brahman---when everything is Brahman why crate division between the world and its perceiver?
How can the world alone cease to exist if one do not look at it—how can the person remain without the world and where he will exist without the world?
Who has the subtle mind projecting through brain and senses? How can one see his subtle mind?--when the brain also piece of the gross matter? ---then how can the brain come into existence after the world is created if the later depends on the brain.
Heart is idea created by mind, how the mind can emerge from it---when the heart disappear along with the mind and reappears along with the mind, how the mind emerge from it.
In deep sleep, swoon and trance, the mind turns inwards and enjoys its natural state--if so why should one inquire if one gets Ataman in sleep. With drug one can get sleep and peace or bliss.
IF sleep gives Brahman then why trouble with inquiry--better get it
through pills. There are many seekers practicing inquiry for many years and waiting for something mystical to happen, why nothing happens and why their inquiry does not yield fruits.
Since, Mahrshi Ramana is not present physically to guide us, seeker to overcome these obstacle in the path of inquiry on his own.