The witness (knower) is that witnesses the coming and going of the three states.

Psychologists regard consciousness as something, which appears and disappears, as relational to something. Gnanis position is the exact opposite, for he regards it as that which does not vanish, that which sees all the three states.  Therefore he  does not regard it as self-consciousness (in Religionists sense) -- that is entirely different. Hence, the term soul, when meant for pure consciousness is not self on the personal limited Religionists sense.

Those who cannot understand Witness and witnessed  Analysis cannot grasp non dualistic  nor Advaitic  truth. Religious believers  psychologists, they combine witness with witnessed  and all the combinations as "consciousness." Gnani separates them and call Formless Witness only as "Consciousness" (the soul, the innermost self).

It is not settled by psychologists what the mind is. They often do not define what it is because they find it so difficult. It is impossible to know what the mind is, because the more they think about it get only thoughts: they cannot ordinarily detach themselves from them, the three states, and be the Witness (the soul, the innermost self). They can go on thinking about mind for a century but all that will come will be more thoughts. 

First, they must   the existence of the formless witness of the three states in order to realize the physical existence is mere illusion.  The thoughts and the thinker and the world are part and parcel of the illusion  which is present in the form of waking experience. The thinker and  the thoughts and the world are one in essence. That essence is consciousness. The consciousness is the innermost self.  The consciousness (soul) is the formless witness of the three states. on the standpoint of the consciousness (soul) the witness and witnessed are one in essence.  Thus there is no second thing exists other than consciousness.    

Gnani does not rule out multiplicity of individuals and things; he admits this separate existence, since it cannot be denied. However, he asks, "What is meant by each existence? What has become of the vanished or changed individuality of each existence? What has become of the child I once was?" When it is superficial and fond of imagining, it can say what it like, but when it go deeper in the inquiry, it sees that multiplicity of the world(duality) is not what it seems.

When one thinks of his body as an infant,  what is that to him now? When he thinks of it again as a youth,  what has happened to it now? When he thinks finally of the body at middle age,where is it now? He  will see that he  had so many different bodies. None can be identified as particularly and permanently his.

It is difficult to grasp at the beginning ,How did ignorance come into pure Atman ?it is due to ignorance. This  ignorance is born of  considering false self as the real self. It causes in the person the contrary of truth and he views and judges the world view on the base of false self. It is the incapacity, the dullness, of the mind to understand it. However, when the mind gets clear, then he "sees" the Truth. Hence, the inability to see is not in the perceiver, but the mind('I') which comes and goes, which hides and prevents one  from "seeing." This "mind('I' )" is like a veil.

It is the illusory reality which prevents one to believe the duality as reality.  mind is the only thing which is available for the seeker , because the whole experience of diversity is nothing but mind.  The mind is something that  comes   and goes, but the formless witness  is untouched by it. Religion does not want truth because it is based on the false self within the false experience.

People who believe their physical self as reality  makes the 'ego'  the center of everything by reducing everything and everyone to mere idea or notions. Religious believers  find itself in danger of falling into this egocentric predicament. Therefore, they avoid it by saying that God creates other minds, persons who really exist in a different way from material objects, which are merely perceived.

All agendas are within the illusion, which appears in the form of mind (universe or waking experience). The self is within the illusion as its formless substance and it is without the illusion as its formless witness. The formless witness is the one which witnesses the body and the universe together.  Thus the ordinary awareness is physical awareness (waking) is not self-awareness.  In self-awareness the body is not the body but it is the consciousness, the ego is not ego but it is the consciousness, the world is not the world but it is the consciousness even though they exist but their unreal nature is exposed. Just as the dream becomes unreal when waking takes place, the waking also becomes unreal when nondual wisdom dawns.

The witness (knower) is that witnesses the coming and going of the three states. This truth has to be grasped mentally to realize the existence of the formless witness. Once this truth is grasped mentally, then one has to cling to the formless witness. Once one clings to this formless witness mentally than the subconscious has the yardstick to accept the truth and reject the untruth. Thus deeper self-search is necessary to understand, assimilate to have a firm conviction of what is what in order to get self-awareness. . 

Deeper self-search reveals the fact that, The soul (consciousness) ,body and world are one in essence therefore no second thing exists other than the soul , which is in the form of consciousness.  Thus realizing all the three states as consciousness leads to self-awareness.