Mind Over Matter?

It was told to me once that our witness
Has power over the physical world.

To me this is something like Romans 
Looking at a flock of birds
To determine whether their flight
Pattern is sufficient an omen,
Or a Babylonian throwing his bone
To see if the lot falls and answers a prayer.

The fact is the mind does not create its own
Reality, but rather picks up on
Subconscious cues built within memory
Which disposes it to believe.
In a sane mind, the thing believed is true.
We know this because some men do not believe
Yet what they don't believe in persists beyond their own awareness.
For they too are beholden to an external world
Which is not subject to perception.
For reality persists despite our objection or ignorance of it;
For, reality is confirmed by witnesses.