Just as the social body is perceived in some way as an ordered, structured system which isconcerned to affirm and protect its order and its classifications, so the physical body ofindividuals in that same society mirrors the social sense of order and structure. Just as the socialbody is concerned about its boundaries (frontiers, city walls, gates), so too the physical body isthe object of concern as to its surface (skin, hair, clothing) and orifices (eyes, mouth, genitals,anus). What crosses the frontier, the city walls and the door of the house is of great concern:strangers are always suspect. What flakes off of the body surface and what pours from its orificesare comparably of great concern. All of these substances are matter which is "out of place" and sodangerous, even "unclean."
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