NOTAN is a Japanese word which means "dark-light." The word, however, means more than that. The principle of NOTAN as it relates to design is defined as the interaction between a positive (light) and a negative (dark) space.
Western culture tends to emphasize the positive aspect of design, with less emphasis on the negative (background) space. The Eastern culture from which NOTAN arose, seeks a more balanced view of the world, and of design as it relates to the world. The classic yin/yang symbol that we all know is a reflection of this desire for balance.
Here we have done the "Expansion of the Square" exercise to study the interaction of positive and negative space. One space is as important as another space to bring to the design.
Both symmetrical (the same all around) and asymmetrical (different on each side) designs can be achieved through the use of the expanded square. In order for the exercise to be completed successfully, it should have an interesting shape in what remains of the original square, feel well-balanced in terms of the expanded parts, and the parts should balance one another. These examples have demonstrated this goal nicely.