Pain is one of our great success stories. That we are still around to say so is itself proof of its enduring value.
The self is a unit, but is not unitary, since I may not know what others think of me, nor even facts about myself that I don’t currently know, such as my genome, or my immune profile.
The self is the sum of a creature physically, biologically, culturally, and personally. A developmental theory of self should be able to explain how these dimensions of self become integrated and functional, in normal cases across developmental time, and how, in abnormal cases, how they become disintegrated and dysfunctional.