Consciousness is a phenomenon, but not an illusion. An illusion is something that seems to be there, yet is not. But consciousness is a self-evident experience.
However, there are gradiations of consciousness. The experience we have on the edge of sleep is qualitatively different than the experience even five seconds after waking up to a cat attack in the middle of the night (I have experienced that).
You’ve stated this so matter of factly that I imagine you have knowledge that somehow has alluded most people.
You mention gradients, which implies you can measure the delta/change of conscious, which implies you have a solid working definition, AND a static still point that does not change which this “consciousness” gradually changes.
From my perspective, which is first person pov, if I can detect changes in my “consciousness”, then where am I looking from to _notice_ this change? Is consciousness not the requirement of change detection?
When I say consciousness is self-evident, I get there by asking myself what it is like to be me.
Whatever consciousness is, it seems vanishingly unlikely that the philosophers talking about it for thousands of years are not talking about this experience I have of being “here now” looking out of my eyes with a constant shower of sensations and interpretations coursing over and by me.
I am not my fingers or hair or forehead in the same vital way that I am this nexus of awareness situated right behind my eyes. But when I am asleep some parts of that awareness are gone. When I am knocked out (by head injury or anesthesia) I so little awareness that I seem to have time traveled when I wake up. (my heart operation seemed to take about one second, and then I teleported to the recovery room).
Sometimes I am very alert, sometimes I am drifting and blinking out. Of course there a gradations of consciousness. Try listening to a book while you are going to sleep.
However, there are gradiations of consciousness. The experience we have on the edge of sleep is qualitatively different than the experience even five seconds after waking up to a cat attack in the middle of the night (I have experienced that).