Self-realization is to recognize that, self is consciousness and universe is illusion. The universe is in the form of mind. Thinking the mind is within the physical body and limiting the Self to the physical entity is cause of the ignorance. due to this ignorance one will not be able to think beyond physicality or duality.
formless soul or Consciousness is the innermost self. The consciousness is the source from where the mind or universe rises and subsides. The mind, which is in the form of Universe, can never affect the consciousness, because the consciousness is the formless substance and witness of the universe, which appears as waking or dream experience and disappears as deep sleep. The consciousness exits in its true nature prior to the appearance of the mind.
Only on the base of the ego or waking entity , which is the false self within the false experience(waking) , the universe seems to be reality but when one becomes aware of the fact that, the self is neither the waking entity nor the dream entity but the self is the formless witness of the three states as a whole, then he realizes the fact that, the three states are mere mirage created out of consciousness. And there is no second thing exist other then consciousness. Hence it is non-dual. Thus, the diversity is myth. Thus arguing on the base of false self[ego] and speculating about the Adavaitic or non-dualistc truth is useless pursuit.
True Self is not the form but the true self is formless consciousness. True Self is ever free - not that it will be free after some time in future. The immortality is the nature of the true self. Hence practicality is – the birth, life death and universe are cause of the ignorance. But the true self has no ups and down because it is formless. The birth, life, death and universe are experienced as reality on the false self [ego] but on the base of the formless true self, they are mere illusion. All problems belong to false self [ego] within the false experience [universe]. The consciousness is the formless substance and witness of the universe, which appears as mind. The consciousness is the deep ocean unperturbed by all the waves [mind or universe] that rise in it sustained by it and goes back into it.
That which is the ground of all proof is the consciousness, which is the witness. All the other means of knowledge such as words, doubts are only meant to remove the obstruction to the consciousness which is always present within the three states as their formless substance. When these obstructions are removed through wisdom, one becomes awakened to the non-dual reality and he begins to see the meanings of scriptural effortlessly. The rise of wisdom is the same as the attainment of self-knowledge.