I believe there are three levels.
The lowest level is the lizard brain.
The middle is the mammal brain.
The final brain is the human.
The three parts of our brain are in constant pull from each other.
The first two are there to take care of us. To help us survive.
The human brain, however, is there to get us to take risks to find meaning.
All the problems we face, if we are lucky, are there to get us to solve the first two parts of our brain and to confront the human brain.
Human problems are indeed the challenge of the times we face.
Josh Allred's Blog 