"When all longings that are in the heart vanish, then a mortal becomes immortal and attains Brahman (infinite consciousness) here." - Katha Upanishad

How many times do we try to hold onto objects of perceptions, taking them to be the real, when in fact it is only the background... the witness of all changing objects that is the real. We cling to these objects out of mis-perception and we have come to take them as reality and as what they (including our body-mind) are as true substance. The body is not true substance (it is always in a state of flux), the mind is not true substance (it is always in a state of flux).It is ONLY the witnessing consciousness that will manifest and unmanifest and still pervail. When the seeker realizes this, through hearing, reflecting and meditating on it that he/she can simply see all false ideas fade away. They will then come to know who/what they truly are