States

Ken Wilber describes the three states that every person has access to, at every stage of development, as the waking, dreaming, and deep dreamless sleep states.

He also describes how those states manifest themsleves in the gross, subtle, and causal realms.

The gross body and the subtle body interest me the most in this area:

I think lucid dreaming gives a person the first access to a "subtle body". I always struggle trying to remember that fact during lucid dreams. It takes quite an effort to remember I don't need to try and walk up the stairs. I can float up, or even just "materialize" at the top of the stairs. But, I still have a very strong connection to my "gross realm" physical body, and my lucid dreams occur so infrequently that I don't get much subtle body practice.