The Silent Gap

An important part of Integral Theory, in short:

Reality is unified (A-dual,) mind creates duality. This can be experienced, and is the gateway to all esoteric knowledge.

A good introduction to this as a meditation here. The music is a little iffy, and the guy also kind of funny, but if you do what he says, you ought to figure out what's being talked about.

While most people identify with the voice in their head, they don't realize a) there are usually at least two competing voices, especially about anything important and b) you are not these voices, but the observer of them. The more and more familiar with the stance of the observer, the more and more you identify with it and disidentify with the voices in your head, the more rich and full your life will be, and the easier it will be to see just how insane and unreal the mind is on a day to day basis.