The middle world is more like our daily life. It is the nonordinary version of our ordinary reality. However, ordinary reality is not to be confused with the middle world. They are quite different. The upper world is the realm of spirits, spirit guides, and ancestors.
Nonordinary reality is an experiential system.
It requires not belief, but experience. While ordinary reality is a thought, nonordinary is an experience. Ordinary reality is thinking. Nonordinary reality is knowledge. Ordinary reality is the basic fiction that we share with one another.