According to Chinese tradition, Laozi 老子 (pinyin: Lǎozǐ) lived in the 6th century BC. Zi is an ancient affix carrying the meaning of "master." (Here it is relevant to note that all of the other ancient thinkers with this title--Confucius, Mozi, Hanfeizi, etc.--have it attached to their family names.)

As with most other ancient Chinese philosophers, Laozi often explains his ideas by way of paradox, analogy, appropriation of ancient sayings, repetition, symmetry, rhyme, and rhythm.