Kamakura, Kenchoji temple
Just as we use language to parse reality to make it more easily apprehensible, we employ boundaries -- parsings of space -- and conventional signs in order to give comprehensible form to the space around us. As an inevitable result of this process the space other than that around is assigned an identity as the amorphous "outside." People have frequently tried to keep the outside, the chaos, at bay by building high walls and impregnable boundaries. They categorized the world according to dualism of inside and outside. But in fact, our species cannot survive if it rejects in interrelatedness to the outside -- that is, our natural environment -- and the people of Japan long ago perceived that we are a more complex and contradictory organisms that the simple digital operation of 1 or 0, "either-or" can explain. This is how many different kinds of boundaries that do not completely separate outside and inside came to exist in Japan.
"Kyokai -- A Japanese Technique for Articulating Space," introduction by Kengo Kuma