““The wall that separates insiders from outsiders is not born of human nature but methodically built, brick by brick, by tribal convention. The "wall" about which I will often speak in this book is not an organism or a membranous extension of some inborn aspect of "human nature". It is a mechanistic process-a barrier meticulously constructed by erratic community decrees as a means of identifying those who are part of the group and marking those who are not. It is not difficult to imagine the chauvinism that require a community to mark its territories and distinguish its members from its enemies. It is far more difficult to understand the kind of "outsiders" who are the subjects of this book-those who are part of the group and yet are rejected by their peers and cast into a terrible internal exile. It is an exile called "alienation".””