Removal of Ignorance (Methodology - Enquiry)
Sankara now indicates as to how  the ignorance can be removed.

He says that Knowledge is not  brought about by any other means than Vichara, just as an object cannot  be seen by any other means than a light.

Dawn of knowledge is not possible  without right enquiry. There are various methods for self-revelation like japa,  tapa, dhyana, karma, upasana etc. But without the right comprehension the  final realization cannot come because it is ignorance, avidya, which has  withheld the light of Knowledge from us. To get at knowledge we have therefore  to remove this Avidya. But so long as we keep ourselves busy with karma,  upasana etc. we remain under their wave. Only when we investigate into the real  nature of this Avidya, it gradually pulls out and ultimately disappears. Then  alone Knowledge of the Reality shines by itself.

How to seek the Brahman/Atman?
The enquiry into the nature of  Truth starts by considering the following questions.
1.Who am I?
2.How is this world created?
3.Who is its creator?
4.Of what material this world is made?

In this analysis the crux of the  matter is to know who we are. In finding out an answer to the question “Who am  I”? Bhagvan Ramana Maharshi spent his entire lifetime. Sri Nissargadatt Maharaj  said “I am That”. The Mahavakya of Chandogya Upanishad announces with a loud  voice “tatvam asi” or “Thou art That.”   Who is that “THAT?” That is the subject matter of enquiry.

We know our name, our body, parentage,  official status, loan outstanding, e-mail ID, our strength, weakness and  threats and so on and so forth ad infinitum. But do we know who we  really are? The answer invariably is that while we know that we are, we do not  know what our real nature is.

The four questions mentioned  above set the tone and direction in which the enquiry and the thinking process should  proceed for finding out the answers to the vexed issues.

Now step by step the reports of  the psycho-pathological tests conducted on the issues involved are being presented  to us by Bhagavadpada Adi Sankara.

He says “I am neither the body which  is a combination of the five elements of matter nor am I an aggregate of the  senses. I am something different from these. This is the way of the enquiry”.

The 1st question “Who  am I?” is answered. I cannot be the body which is made up of five elements and  which is perishable in nature. The Consciousness in me is constant and never  changing but the physical body is ever changing and liable to be destroyed one  day.  Similarly, we are the users of the  sense organs like ears, eyes etc and we are not the aggregate of them because  we are aware that there is somebody else within us who enjoys or suffers  because of these sense organs.  We also  know that these sense organs are of no use when they are not activated by  another force. This life giving force is Consciousness. This consciousness  operates within us in all the three states of waking, dreaming and deep sleep.

In the waking state, we think we  are the body, the physical being and consequently feel ourselves as strong or weak,  beautiful or ugly, short or tall, lean or obese, diabetic or cancerous etc. In  the dream state, regardless of our physical structure, we make a holiday trip  to a foreign land. In this strange land we are turned into spectators and victims  of our own thoughts stored in our mental strong rooms gathered during the  current birth as well as in our past avatars. We suffer or enjoy the  consequences of this holiday trip as long as the trip lasts and we laugh at or  ignore the whole dream experience on returning to our own native place of the  waking state. In the deep sleep state, we go to a place where there is no  mental or physical disturbance and hence find it very peaceful. At this state  we cannot assert or deny our own existence. There is one more state called Turiya which requires another platform to deal with.

Although we pass through these  states of mind every day, we cannot say with certainty which of them really  conforms to our real nature because our real nature is different from the body  and sense organs.