Hi TTN,
Not sure which three schools you are referring to.. But the Upanishads definitively declare, "Tat twam asi" and "Aham Brahmasmi" (I am That, I am Brahman). In Advaita, Brahman is called "one without a second"..
In this, there is simply no relation "between" Brahman and me. So, what is the "me" anyway? Also called the ego or the separate self, the "me" is simply the assumption that I as a body/mind exist on my own, and separately from the rest of creation (aka, "not me"). This sense of ego or me is strengthened by repeated assertive beliefs such as "I exist", "I have free will", "I am the maker of my destiny" and others that give the perception of volition. Paradoxically, even the effort of spiritual practices increase the sense of separation for a very long time, because there is a "me" meditating, doing karma yoga, etc.. Bit of this is here:
http://www.aypsite.com/plus-forum/index.php?topic=14195There comes a point in everyone's journey where this illusion of me is seen through - while actions happen, the labeling that "I did it" happens "ad hoc". When closely examined, the sense of volition is merely a thought/belief/concept. Actions have always happened in response to something - a cascade that is untraceable beyond a certain time point, vasanas, etc. In Buddhism, this may be akin to what is called "dependent origination". Nothing happens independently; thus, the assertive beliefs of free will and "I exist" are seen through. At this point we relax from "I am so-and-so" to "I am That", That being nameless, formless awareness, i.e., Brahman.
But the journey does not seem to end here, because there is still a duality of "I am Brahman, not so-and-so". When we learn to rest as That, we can see that all arisings (actions, thoughts, feelings, etc) arise out of this nameless, formless awareness and recede back into it. As what? As awareness itself. The sense of "me" arises from Brahman AS Brahman and recedes into it. What complicates this pure process? See, the "me" is a thought in response to another spontaneously arising thought. Say a thought arises - how does it become "my" thought? By the next thought that names the first one so. Suppose the second didn't arise.. the first would just be "a" thought that arises from awareness as awareness and recedes back into it.. Thus, as this is seen with increasing clarity, there is just what is happening, there is no doer.
Even the sense/thought of "I am That" is added "ad hoc" if closely seen. Brahman is beyond consciousness, beyond perception, beyond description..
Hope this makes some sense..
Love.