This article was first published on Big Think in September 2021. It was updated in March 2025. No person is one thing. The kindest person you know has a tiny recess of cruelty in them. The happiest person you have ever met will have their depressive moments. The gentlest person you can think of can be filled with rage by one particular thing. There is no purity of any kind; life is a messy cocktail of things. This is the truth behind one of the most famous symbols (and tattoos) in the world: the Yin and Yang. Well en-Dao-ed wisdom For such a well known idea, the Yin and Yang only appears in one line of the central Daoist book, Daodejing . And yet, it is essential to Daoism and is, in many ways, interchangeable with the Dao itself. Lao Tzu is the semi-mythical founder of Daoism (or Taoism — the sound is halfway between a T and a D to the non-Chinese ear). His name means “Old Master,” and it is unclear if he was a single historical person or a title given to a collection of sages and their works.…