Firstly, the Yin & Yang principles described in the I-ching (Classic of Changes) can indicate many polarities such as the sun & moon, day & night, light & dark, motion & rest, internal & external, cold & heat, hard & soft, and male & female.
首先，衍生自「易經」的陰陽，可以指日和月，也可以指晝夜、明暗、動靜、內外、寒熱、剛柔、男女… … 等等無所不在的各種現象。