Ensō

In Zen Buddhism, an ensō (, , "circle"^?) is a circle that is hand-drawn in one or two uninhibited brushstrokes to express a moment when the mind is free to let the body create.

The ensō symbolizes absolute enlightenment, strength, elegance, the universe, and mu (the void). It is characterised by a minimalism born of Japanese aesthetics.

Drawing ensō is a disciplined-creative practice of Japanese ink painting—sumi-e (, "ink painting"^?). The tools and mechanics of drawing the ensō are the same as those used in traditional Japanese calligraphy: One uses a brush (筆, fude^?) to apply ink to washi (a thin Japanese paper).

The circle may be open or closed. In the former case the circle is incomplete, allowing for movement and development as well as the perfection of all things. Zen practitioners relate the idea to wabi-sabi, the beauty of imperfection. When the circle is closed, it represents perfection, akin to Plato's perfect form (Plato), the reason why the circle was used for centuries in the construction of cosmological models, see Ptolemy.

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