Both sides of experiences have to be inquired into--the duality (waking or dream or universe) and Non-duality (deep sleep).+

Self- Knowledge or Brahma Gnana or Atma Gnana is only is the true knowledge,  not the absence of the duality.  Self -Knowledge or Brahma Gnana or Atma Gnana cannot destroy the world, but it eliminates ignorance and exposes the unreal nature of the mind, or the universe.  

Man cannot live without the physical world; it is the basis of his life, so it must be the starting point of his inquiry. Things, not imaginations, must be the seeker's material.

The one who knows ultimate truth or Brahman knows the world because uses his soul-centric reason.

One who loses touch with the external world and gives himself over to his thoughts alone takes his illusions to be reality and he remains to exhibit his perverted intellectualism, never reaches the ultimate end of understanding. Perverted intellectuality is nothing but an egoic exhibition.

Both sides of experiences have to be inquired into--the duality (waking or dream or universe) and Non-duality (deep sleep).  If one wants to find the truth of his true existence, he must know, the knowledge of both matter and Spirit.

People avoid inquiry into the world, hence cannot find the truth. If one thinks he does not see the world by shutting his eyes and omitting it from his thought, he is still ignorant and not a Gnani.

If there is nothing to be seen, if merely the absence of the external world from cognition gave the ultimate truth or Brahman, then every living creature would attain Gnana or wisdom, because it loses the world in deep sleep.

The seeker must begin Inquiry with duality, i.e. with the universe to inquire into. It will end with unity. People try to avoid this duality by ignoring the world. Hence,  they get a false unity based on the ego (waking entity). All the theories based on waking entity (ego) is mere hallucination based on the imagination.

There is a need to indulge in deeper self-search in order to explore the causes, characteristics, and nature of the universe.  There is no need to go running to the mountain or a monastery or lead a religious regulated life in order to get ultimate truth or Brahman.

There is no running away from the soul, is present in the form of consciousness. The soul is the innermost self. The soul is the only reality. Hence running away from the world is not only illogical but also foolishness because without consciousness the world ceases to exist.  Thus,  it is necessary to know the universe as a whole,  in order to understand the whole universe is non-dual consciousness. 

Gnana cannot come if the world confronts one is left out. The whole universe must be included in the inquiry. Only when all is known can all be known to be but ideation. Hence yogis blotting all out in Samadhi cannot lead to Gnana. And yogic Samadhi is not wisdom. And it is foolish to accept the thoughtlessness is Gnana,  because, deep sleep is the state of thoughtlessness, but it is not considered as Gnana or the nondualistic or Advaitic wisdom.

The ‘I’-thought, the ego, belongs to the duality as does the universe thought. Intellectuals may get the knowledge that the witness is separate from witnessed, but they will never know the ultimate truth or  Brahman without inquiring into the universe because they are giving up the universe, and hence cannot discover their unity with the universe. The Gnani regards everything in the universe as consciousness; the intellectuals reject the universe because intellectuals base themselves on individuality. 

Individuality is the greatest hindrance in pursuit of truth because they base themselves on ‘I’ as a witness, which is not a witness,  but ‘I’ is merely an object to the formless witness

The Soul or consciousness cannot be known in the sense in which one knows objects of thought. It can be known only to the extent to which he knows them, he can only think of the knower when he is in the presence of the known, i.e. the objects, for the latter make him aware that a knower must exist. Thus duality makes him think of the knower, but it cannot make him know the knower. The knower is known in the world of duality only by implication, as he cannot think without him. The knower is a concept, and cannot be known in itself.

The Soul or consciousness is known only in the negative way. One cannot make it an object of knowledge. One can know that he cannot have an idea of an object unless he posits a knower unless the knower is implied already. The Formless witness itself is Gnana, that is, it knows everything else.

The Self is known only when one sees something else, for that other thing reminds him of it. The self is unknowable as an object. Knowing the ultimate truth means knowing that consciousness exists. The world knows implies duality, something known; on the other hand, Gnana does imply an object. 

Consciousness knows the ego as an object. The knowing powers, the formless witness, the knower can have no statement made about it, other than that its existence cannot be negated. The ultimate truth which one can know is that consciousness is not something to be known.

There is no need to run from pillar to post, one ashram to another ashram, and one guru to another guru's order to acquire nondual wisdom. The seeker of truth has to strive to understand the nature of the mind or the universe and thus conquer it by knowledge.

Without inquiry into the nature of the universe or waking and its nature i.e. the matter, there can be no such thing as Gnana. Religion, yoga, the concept of God is unimportant in pursuit of truth. The scriptures are not at all necessary in pursuit of truth, but one can quote the citation of the scriptures which indicate the ultimate truth after deeper verification.  

The intellectual will not find the truth because his understanding based on individuality and individuality is not truth on the ultimate standpoint because the self is not an individual because it is formless and it pervades in everything and everywhere in all the three states. Most of the intellectual says “I know” and does not explain how he knows consciousness is the ultimate truth. But his egocentricity makes him more and more egoic and he indulges in perverse argument, which is not needed in pursuit of truth.:~Santthosh Kumaar