a Taoist philosophy, the basic differentiation in to duality of all things in Nature, it is first mentioned in the I Ching (over 3000 years ago)
the Tai Qi symbol represents seemingly opposite forces in continuous complimentary, interconnected and interdependent relationship always transmutable from one to the other
hot/cold, female/male, sun/moon, winter/summer, up/down, sad/happy, hungry/full and on we go…