Geometry and Outside

The notion 'Outside' is commonly represented geometrically by a two-dimensional figure that is posited as dividing the surface into 'inside' and 'outside'. One difficulty with such a procedure is to settle the status of the perimeter of the figure. It seems to be neither inside nor outside, but, on analogy, a wall of a house is not neither, but both, e. g. its papered surface is on the inside of the house, while its shingled surface is on the outside. With those two surfaces only a matter of inches apart, where the inside ends and the outside begins is not easy to establish, e. g. the midpoint between them is in neutral territory. The deeper flaw is that 'Outside' connotes not a location, but an orientation--e. g. the shingled surface of a wall is not on the 'outside' of a house because of its distance from the wallpaper, but because of the fact that it faces away from the house. Furthermore, this 'facing away' does not connote a static juxtaposition of the wall and the air around it, but a dynamic development of a beyond with respect to the surface. In other words, 'Outside' is an hypostasization of 'Outwards', a notion to which, even with the use of a vector arrow, geometrical illustration seems inadequate.