Enquiry opens the aspirant's eyes to new vistas of knowledge.
It leads him steadily to Truth.
For instance, if the aspirant starts the "Who am I?" enquiry, he will soon find that he cannot equate himself with any one of his sense organs like the nose, the eyes or the ears, because even without one or more of these, he can live and life can pulsate in his veins.
So, he is not the body.
Nor is he the mind, because even during the unconscious and the deep sleep states, when the mind ceases to function, he exists and his heart throbs.
Then, what is this 'I' in everybody?
Swami Sivananda declares that the real 'I' is none, else than Brahmam or the Atma who is the motive force behind all existence.
It is He who thinks through the mind, sees through the eyes, eats through the mouth, hears through the ears and so on He is the Witnessing Consciousness who dwells in all beings.
When a person gets up from deep sleep and says, "I enjoyed a sound dreamless sleep", it is this Witnessing Consciousness which remembers the fact that the body and the mind rested in sound sleep.
It cannot be otherwise.
To be continued ...