A figure used in many Asian cultures to symbolize the unity of the two ``opposite'' male and female elements, the ``yin'' and ``yang.'' The solid and hollow parts composing the symbol are similar and combine to make a Circle. Each part consists of two equal oppositely oriented Semicircles of radius 1/2 joined at their edges, plus a Semicircle of radius 1 joining the other edges.
See also Baseball Cover, Circle, Piecewise Circular Curve, Semicircle
References
Dixon, R. Mathographics. New York: Dover, p. 11, 1991.
Gardner, M. ``Mathematical Games: A New Collection of `Brain-Teasers.''' Sci. Amer. 203, 172-180, Oct. 1960.
Gardner, M. ``Mathematical Games: More About the Shapes that Can Be Made with Complex Dominoes.'' Sci. Amer. 203,
186-198, Nov. 1960.