All it is is a simple circle. That's what I started with. After hundreds and hundreds of pages of the psychiatry texts of my training, hardly ever were Personal Boundaries even mentioned. And yet they are the most powerful force (beyond our passions), and one of the only forces that make us HUMAN (as opposed to advanced animals.)
If the passions of the "Reptilian Brain" I always talk about were like an "accelerator pedal on your life, then the Personal Boundary is your "brake pedal."