The self is steadfast and constant. It is an un-moving, non-judging observer. To do otherwise is to form identification giving rise to something separate. Rising from the self is the mind. The mind provides commentary and observation on the outside world or reality. The mind, through perception and interpretation, gives rise to the body. The body is the thing that forms a physical barrier between us and the outside world. This is where we start to actually perceive ourselves as separate which gives rise to others and everything else.
Here is the thing. That mind-body perception is just one of many. If this mind-body arises from the self, then everyone that I am perceiving is arising from the self. The self emanates out from underneath this mind-body, but it also spreads out from everyone and everything that this mind-body perceives. So this mind-body is one in many forming many in one. I am a projector and a receptor of the self.