THE M-HOUSE, TOKYO. In the words of Kazuyo Sejima and Ryue Nishizawa, the architects who designed this sunken dwelling in the center of Tokyo, the central courtyard serves to “bring the outside into the interior, while at the same time securing privacy for the living space.” . What makes the design of this house unique is that most .of it is one level below grade, with the minimalist, almost .austere garden acting as a light well. Small though it is, the pace seems larger, partly thanks to its transparent and .translucent walls, and partly because of the height of the .excavated area. Decking and a single dogwood comprise .the entire garden. The tree was carefully chosen for its soft nd delicate lines, which counter the austerity of the space. Walls of glass and translucent polycarbonate reflect and reinforce the centrality of the design. Light entering directly from above is filtered through white-painted steel louvers, which give an added measure of privacy, and also cast a lovely pattern over the garden in the middle of the day.