With thoughts, feelings, sensations, sights, perceptions
there is one 'thing' common to them all.
One factor is always present, unvarying.
What you are before you add something.
I am a woman, I am a man, I am long, small, I am a strapping young fellow, I am struggling with some issues, I am ugly, stunning, plain, I am depressed, irritated, ecstatic, I have had childhood traumas etc. The list is endless.
Before you can say any of those things, or come up with zillions
of other descriptions there has to be first something on which
those description are hooked.
This is the sense of being.
Your basic sense of identity.
Which has no shape or form or location or description.
The only thing we know about it, is that it IS.
This perception I is the first principle.
All else is added.
This IS and all plays and dances on it, in it, as it.