I learned why this symbol is on the cover of so many minimalism and self help type books, and in logos!
The ensō symbolizes absolute enlightenment, strength, elegance, the universe, and mu (the void).
Zen practitioners relate the idea to wabi-sabi, the beauty of imperfection. When the circle is closed, it represents perfection.
Usually, a person draws the ensō in one fluid, expressive stroke.
