The world in which we exist (waking) is a merely a superimposition like seeing a snake superimposed on a rope on a dark night.*****

The Soul the Self has no attributes. Hence, the person who superimposes attributes on the changeless, eternal Soul, the  Self and identifies Self with the body is confusing one for the other; and is, therefore, an ignorant person. 

The Soul the ‘Self’ is the One without a second. There is not the least shadow of multiplicity in the realm of the Soul which is present in the form of the consciousness."

A person, seeing a rope in dim light, mistakes it for a snake. He is as much frightened as he would have been if there had been a real snake there.  The snake is said to have ‘illusory reality’.  The illusory snake is described as a superimposition on the rope. The snake is not real, because, it is found on examination with a light that it never existed there. At the same time, it was experienced as a reality till ignorance prevailed. Similarly, this waking experience experienced as reality till wisdom dawns.  On the dawn of Self-knowledge or Brahma Gnana or Atma Gnana, it is known to have no existence apart from consciousness. The consciousness is the ultimate truth or Brahman. The waking experience is therefore said to be superimposed on consciousness same way as the dream is superimposed on the consciousness.  The waking experience is a practical reality because it is real until the attainment of  Self-realisation.  Consciousness alone has absolute reality; because it is absolutely changeless because it is formless timeless and spaceless existence.    

 That is why Sage Sri, Sankara says:~ VC -65~ As a treasure hidden underground requires (for its extraction) competent instruction, excavation, the removal of stones and other such things lying above it and (finally) grasping, but never comes out by being (merely) called out by name, so the transparent Truth of the Self, which is hidden by Maya and its effects are to be attained through the instructions of a knower of Brahman, followed by reflection, meditation and so forth, but not through perverse arguments

Remember:~
1. 

The waking experience which is referred to as the witnessed  and the formless Soul which is present in the form of consciousness is the Self, referred to as the witness of the witnessed  are wrongly looked upon by every one of us  as equally real, though the waking experience has no reality in the absolute sense.

 The Soul, the Self, which is present in the form of the consciousness is ultimate reality or Brahman. The waking experience   appears to  be  real in the same manner as,  when a rope is mistaken for a snake, the illusory snake appears to be real.  The snake is said to be superimposed on the rope. The body and the world are within the waking experience. The waking experience is an object and the formless Soul or consciousness is the subject.

All the three states are an object to the formless Soul or consciousness which is the subject.  One finds the object and the subject are of different natures. Their relationship is of the form of superimposition of each on the other as also of their qualities, as a consequence of the absence of discrimination between the real nature of the witnessed and the witness of the witnessed. 

This is like the association of a rope, nacre, etc., with the superimposed   snake, silver, etc, owing to the absence of discrimination between them. The association of the witnessed and the witness of the witnessed in the form of superimposition is described as false knowledge.    

After having known the distinction between, and the nature of, the witnessed and the witness of the witnessed one becomes aware of the fact that the witness and witnessed are one in essence. And that essence is consciousness.  Thus, from the ultimate standpoint, there is no second thing exists other than consciousness, hence it is nondual.

He who realizes the witness of the witnessed are one in essence and who has the firm conviction realizes the three states are unreal. Though the three states appear as real on the dawn of non-dualistic knowledge their unreal nature is exposed.  

Remember:~

2

The world in which we exist (waking) is a merely a superimposition like seeing a snake superimposed on a rope on a dark night.

The snake has no independent existence, apart from the rope, it exists because of the rope, and it ceases to exist as soon as a light is brought. The snake then dissolves into the rope. In the same way, when the Soul remains in its own awareness, the mind (I)    merges into it.  The mind and Soul are one in essence. To attain this knowledge is the goal of the truth seeker. The three states then cannot taint the Soul, the innermost Self.

Thus, Gnani’s contact with it is merely like that of a piece of sandalwood, which has long been under water and has thereby come to acquire a bad odor. For a while, the fragrance of the sandalwood been suppressed and the bad odor prevails. However, if the sandalwood rubbed a little, the bad odor disappears and the natural fragrance of the sandalwood becomes predominant.

Similarly, the Soul, the  Self’s attachment to the three states is temporary. It cannot be permanent. Think of the Self as the Soul or the consciousness. When one thinks intensely and constantly in this way, the attachment to the three states will then go.

 One can attain the Self-knowledge or Brahma Gnana or Atma Gnana by the practice of renunciation of the three states. One has to keep reminding himself that the three states, with all its allurements, are not real, that is, it is not real in the sense that it is transitory. Only the formless Soul   is real because it is imperishable. One must mentally renounce these three states and concentrate on the Soul, the innermost Self. Seeker of truth should never run after things, which are ephemeral. Never become attached to the three states, which are ephemeral.

To one who knows the fact that these three states are transitory, the world is not the world and any form of sense pleasure is repugnant. Seeker of truth must be concerned only with the Soul, the innermost Self, become steeped in the Soul. The Soul alone is real and the Self is that Soul. The Soul is in the form of consciousness and becomes oblivious to everything else. : ~ Santthosh Kumaar