The very substance of every experience is the substance of Consciousness.
Objects do not just appear in Consciousness they appear as Consciousness
Consciousness does not just witness every experience, it expresses itself as every experience.
Everything that is experienced is experienced by, through, in and as Consciousness.
Consciousness witnesses, experiences and expresses itself from moment to moment, and when there are no objects present, it simply remains as it always is.
That is all there is.