The antonym is outside. The surface of a body is the limit of what is inside & outside. What belongs
Anatomical cross-section of human arterial circulation and building section, Diderot and d’Alembert, Encyclopedie, Home decorations 1751-1772. The Encylopedie offered two definitions of the interior: the first one as everything inside the human body, both physical and mental; the second one as anything contained and separated as an enclosure from the exterior world, like the insides of a building. These two plates from the Encyclo-pedie-one anatomical and one architectural – show attempts to graphically capture both meanings of interior to this surface, & all that is placed beyond where one looks at or touches the body is exterior. Anything that is beyond the surface, in the depth of the body, is the interior.5
Diderot’s definition suggests a wider notion, perhaps still elusive in design, that combines both palpable surface effects and ones that touch the very core of our being. He offers two complementary readings of the interior: one that can be applied to buildings and another that applies to people. The interior of a building, as Diderot defines it, is merely the inside, or everything from the walls inward. But as the interior relates to the human being, it reflects both our outward personality and what we might today call our inner self. What is most interesting about Diderot’s definition is that it begins to suggest that what is inside the walls and what is inside ourselves may overlap.
Accordingly, the interior is the best medium through which to address the interaction between human beings and design. The interior is not, as widely thought, the simple outfitting of a room but, rather, the manifestation of all qualities concerning the human occupation of space.