- Root meaning: moonlight (dark) and sunlight (light). Yin later came to be associated with female, negative etc. Yang later came to be associated with male, positive etc.
- c. 479 BCE - 221 BCE: Confucius, 周易/繫辭上#第五章 (Zhou Yi, Appended Words Part one, Chapter five)
- That which can not be measured (in straight forward terms such as) black and white (bad and good; negative and positive etc.) is called mysterious (or divine)
- negative and positive; yin and yang; yin-yang; ☯