Just want to coin a new term for the barrier between self and 'other'. By narcissistic I do not mean "bad", I mean self-refractive like two mirrors facing one another, or like a pond surrounded by the shoreline. What I like is how we can navigate inside and also at the edge, and even peek out of the edge and glimpse the total difference of what is like outside the encirclement.
I think children (very young, as in age 4 and below) don't have a narcissistic encirclement yet and so basically live in the outside world as a proxy of it. What madness they must experience! But also a kind of simple purity of action and willing, not confused by differences between inner and outer. But then "the self" forms, a personality can develop due to narcissistic encirclement, and also this thrusts upward being into new heights as dis/agreements are now needed to be negotiated rather than simply responded to.
A philosopher is someone whose narcissistic encirclement is very intense, the boundary is severe, but the 'pressure' of the inner space is so extreme that it forces expansions outside the encirclement boundary. When Nietzsche went mad he didn't simply collapse with that horse and then lose his mind and stop speaking, no-- he collapsed and then went for a few days in a sort of in between state, alternating lucidity and madness, drawn aloft from himself into the world and without recognizing the boundary between himself and others (for example, didn't understand how outside events were affecting him or focused on him), and then would switch to being trapped inside himself and unaware of the outside world and entirely passive in terms of it. I think the pressure of his narcissistic encirclement blew out the 'ring' boundary around himself, and he was forced to exist only by pure force of his own gravity of self, but without a boundary that isn't possible to do and still maintain what we call sanity. There's a nice epilogue in my book of his Letters that explains details from his last few days before being committed, and then a brief overview of some of his commitment.
Building up the inner pressure of our self requires a stronger boundary between oneself and the world. A philosopher is one who feels the heat and fire of the world so intensely that he is forced to augment his boundary, his narcissistic encirclement, in order to protect himself, and this reinforcement allows for much more inner self-pressure to develop. In fact the self-pressure must increase if the boundary is becoming harder and thicker, otherwise one feels that oneself is shrinking into oneself and liable to vanish.