To acquire Self-Knowledge or knowledge of Brahman no qualification is actually needed.

The formless soul is the innermost self. The innermost self, is in the form of consciousness.  the nature of soul is,  whole and oneness. In the cloud there is nothing other than water, so too consciousness is nothing other than itself. It is the absolute without a second.

 The moon reflecting on water and appearing as many, the self is just like the reflection of the moon on water which increases with the volume of water and decreases with its reduction, which moves when the water moves, and which differs as the water differs. The moon seems to conform to the characteristics of water, but in reality the moon never has these increasing or decreasing qualities. So also, from the highest point of view, consciousness always retains its sameness; it seems to conform to such characteristics as increase and decrease of the limiting adjunct, owing to its entry into such an adjunct as a universe. 

Thread is drawn from cotton and is woven into cloth. But the reality of cotton is in both of these forms, viz., thread and cloth. Similarly, the projections of names and forms of this material universe on consciousness do not alter the nature of consciousness. It remains as it is without any change.

 One can also illustrate the uniqueness of consciousness by analyzing the phenomenon of dreams. Dream is parallel waking experience. And waking experience is parallel. The three states are an object to the subject, which is formless consciousness. The consciousness is the formless substance and witness of the three states one is unaware of the subject because he considers the waking entity as self and views and judges the three states, which is erroneous. The waking entity is limited to the waking experience, and the dream entity is limited to the dream experience. In deep sleep the waking or dream experiences are absent, thus the witness remains in its formless non-dual true nature, but due to ignorance of the true self, which is the substance and witness of the three states, one experiences the three states as reality. When one becomes aware of the formless witness of the three states then one becomes aware of the fact that, the three states are mere mirage on the standpoint of the true self, which is consciousness.  

Thus whatever seen, known, believed and experienced within the waking experience is falsehood.  Thus the experience of universe and birth, life and death are myth. Thus the belief of god, heaven, hell, paradise, sin, karma, rebirth, reincarnation is myth.  

Thus by worshiping individualized god and following religion studying scriptures are for those who are incapable of realizing the truth of their true existence.   

Waking and dream emerge from consciousness. The emergence of the waking or dreams does not make any difference to the consciousness. The consciousness remains unchanged and unaffected by the waking or dream, even though both the waking or dream objects and the waking or dreams are aspects of the consciousness. 

The dreamer would not realize that dream objects and the dreams are simply aspects of the consciousness unless he wakes up from the dream. Once the waking takes place the dream becomes unreal, same way when wisdom dawns the waking becomes unreal.  The unchanging reality behind the waking or dream experience is the consciousness. 

 The waking or dream experiences are external manifestation of consciousness. As long as a person is caught up in the phenomenal existence, he does not see the unity behind the multiplicity. When one wakes up to the consciousness as it is in itself, not perce perceived or interpreted, or noumenal   level he becomes aware of the one, non-dual consciousness, which was the cause of the three states.  

Thus, consciousness is supreme. It is the reality. It has no beginning and end. It is eternal and beyond the reach of pain and pleasure. Consciousness is indivisible, immeasurable, without names and forms. It cannot be avoided, as it is present everywhere. Consciousness cannot be grasped, as it is transcendent. It cannot be contained in anything, as it contains everything. Consciousness is indefinable, for it is beyond the range of action and speech. Thus, consciousness is reality itself, pure and absolute consciousness.

Consciousness is ultimate reality is defined as that which persists. Consciousness exists in all periods of time and remains the same in the past, present and future.

Consciousness is ultimate reality exists both in the manifest and the unmanifested. The mind, which is in the form of universe arises out of the consciousness .The consciousness exists in all the three states. The mind rises from it and Merges back into consciousness. 

Consciousness is the substratum and the three states. Consciousness is like the ocean and mind is like wave. Wave exists in ocean and Merges back into ocean. Similarly the mind or universe is nothing but consciousness. Everything is consciousness.

Therefore, consciousness is a principle of utter simplicity. There is no duality in consciousness for no qualities are found in the concept of consciousness. It is also simple in the sense that it is not subject to inner contradictions, which would make it changeable and transitory. To understand the nature of consciousness and to speak of it, consciousness in its reality, is not a metaphysical postulate that can be proved logically, but it must be grasped and realized mentally not through argument or logical conclusions but perfect reasoning. Thus, consciousness is one: It is not a `He or She ', a personal being; nor is it an `It', an impersonal concept. It is that state which comes about when all subject-object distinctions are obliterated.

 

 To acquire  Self-Knowledge or Knowledge of Brahman no qualification is actually needed. It is possible to have the realization of the ultimate truth or Brahman here, in this very life.

The universe appears as waking or  dream (duality) and disappears as deep sleep (non-duality). Gaining the knowledge of the knower of the three states, is the only way one can transcend the triad of states.  To gain this knowledge by perfectly analyzing   the very states of dream and sleep in the waking to benefit from the states rather than becoming victims of the states.

A Gnani knows that the enjoyment of desires within the waking also is as unreal as in the dream, because he is fully aware of the fact that, the self is neither  the waking entity, nor the dream entity  but self that which witnesses the three states.  Thus, the universe, which appears as waking or dream is mere illusion created out of consciousness, which is the substance and witness of the three states.   

The pain and pleasure are part of the waking or dream. The waking or dream is an object to the soul or consciousness ,which is the formless subject. 

When awake, one should, first picture to himself vividly what he has seen in a dream and then carefully and constantly think over the conditions of dreaming and wakefulness and  analyze and realize the fact that,  the witness of the three states is formless and part. The witness is nothing to do with the individual happenings within the universe, which appears as waking or dream. 

  The dream entity and dream universe is nothing to do with the waking entity. The waking entity and the waking universe is nothing to do with dream entity.  In deep sleep the witness remains without the waking or dream experience.  In waking ,  the waking entity is aware of the dream or deep sleep experiences but the waking entity was absent in dream or deep sleep. Thus one which is aware of the three states is neither the waking entity not the dream entity because the deeper inquiry revels the fact that,  the self is not physical but self is formless soul or  consciousness.   The one which witnesses the waking or dream is not the form but it is the formless, because the form is limited to the waking or dream.  Thus the witness is that which witness the waking or dream experience as a whole without the physical apparatus. 

Seeker must observe deeply and find out the essential similarity of the dream and waking experience. He should realize the fact that, the witness of the three states is formless and apart.  He should then give up the notion of the reality of the waking experience, same way he gives up the dream realities, when waking takes place   and cease to be attached to both waking or dream, by holding mentally  the formless witness as real and eternal.