Consciousness is not identical with waking consciousness which is rather a particular relation to objectivities. When waking consciousness fades a myriad of subjective phenomena become salient and when these are no longer linked to the waking world then dreams arise, which represent the action of a different kind of object. Dreams nd as well and a different kind of conjoined pure feeling is experienced. The characteristics of consciousness do not resemble are of these modes of object awareness, but are what is common and unchanged between them. This is one of the things you know without knowing.