bāɡuà 八卦
Eight Trigrams
由“—”（阳爻）和“--”（阴爻）每三个一组合成的一套符号系统。三“爻”合成一卦，共有八种组合，故称“八卦”。“八卦”的名称分别是乾（
）、坤（
）、震（
）、巽（
）、坎（
）、离（
）、艮（
）、兑（
）。古人认为“八卦”象征着自然或社会中的一些基本事物或现象，其基本的象征意义分别是天、地、雷、风、水、火、山、泽。古人借由“八卦”彼此之间的交互演变及其象征意义，来理解和阐发自然与社会的运行变化及其法则。
Each of the eight trigrams consists of three lines and each line is either divided (--) or undivided (—), representing yin or yang respectively. The eight trigrams are: qian (), kun (), zhen (), xun (), kan (), li (), gen (), and dui (). According to the ancient Chinese, the eight trigrams symbolized basic things and phenomena of nature or society and represented heaven, earth, thunder, wind, water, fire, mountain, and lake respectively. The ancient Chinese also used the interchanges and transformations of the eight trigrams and what they represented to understand and expound on natural and social changes and to explain why and how they took place.
引例 Citation：
◎古者包牺氏之王天下也，仰则观象于天，俯则观法于地，观鸟兽之文与地之宜，近取诸身，远取诸物，于是始作八卦，以通神明之德，以类万物之情。（《周易·系辞下》）
（古时伏羲氏统治天下，仰头观察天上的物象，俯身观察大地的法则，观察鸟兽的斑纹以及地上适宜生养之物，近处取法于人体自身，远处取法于万物的形象，于是初始创作了“八卦”，以会通事物神妙显明的本质，以区分归类万物的情态。）
When Fuxi was the ruler under heaven, he looked up into the sky to observe celestial phenomena and looked down on the land to observe geographical features and examine the images of birds, animals, and all other things that existed on earth. He selected symbols from the human body close by and from various objects far away, and then invented the eight trigrams to explain the miraculous nature and distinguish the states of all things. (The Book of Changes)