The Hall of Mirrors is said to be an extremely dangerous place.
(At pages 297-299 in my copy of Chapterhouse: Dune, the bashar Miles Teg recounts his inner journey to the Hall of Mirrors.)
How to travel to the Hall of Mirrors?
If you try to pinpoint your identity, your thoughts lead you from one self-image to another. If you're persistent following the trail of self-images, your mind grasps a handy association: reflections.
Thus, your awareness arrives at the hall of mirrors.
Duncan refers to approaching this depth as "Fascination of the 'ego core'."
Within this fascination lies the danger:
While looking from 'above', you create a placeholder watcher-self, distanced from the mirrors. If the distance is preserved even at close proximity, the awareness is lost in the overwhelming and infinite fascination.
You lose your grip on yourself because you're fearful of not having one.
A static self-image... the Hall of Mirrors rips it apart.
If you stick to it, that's what you get: a ripped-apart static self-image. Hop from image to image and get lost in the maze of reflections.
If you lose coherency, you become a vegetable.
Fortunately for someone who is lost, there are ways to deal with the situation.
In a motion of flux, mirrors can be broken, created - or ignored.
The reflections do not necessarily limit or lock into patterns, but we must have the strength to break away into the unknown.
To become someone new.
Be sure to enjoy the scenery!