We live in world full of boundaries, that helps us to distinguish between right an wrong. But most of all it allow us to understand what is mine and what is yours.
We have the need to know where do I finish and where do you start, is a human need that keep us safe from physical obstacles, and we have taken far beyond in order to define property and power.
Is this boundary that divide mine and yours what keep us fight for power, with the idea that IF i have more than you THEN I would have more power.
But what is really ours? if when the river floods it would take my border your border, it wont distinguish if I'm wealthy or powerful it would take us all as the same.
Is so easy to recognize when I'm in my side and when you are in yours, but the limit would always be a blurry zone. If not sure, ask to lovers were those one begins and the other ends when they are in the act of love.