Laozi (Chinese: 老子, Pinyin: Lǎozǐ; also transliterated as Lao Tzŭ, Lao Tse, Laotze, and in other ways) was an ancient Chinese philosopher. According to Chinese tradition, Laozi lived in the 6th century BC, however many historians contend that Laozi actually lived in the 4th century BC, which was the period of Hundred Schools of Thought and Warring States period. Laozi was credited with writing the seminal Taoist work, the Tao Te Ching (also known simply as the Laozi).
Laozi's work, the Tao Te Ching, is one of the most significant treatises in Chinese philosophy. It is his magnum opus, covering large areas of philosophy from individual spirituality and inter-personal dynamics to political techniques. The Tao Te Ching is said to contain 'hidden' instructions for Taoist adepts (often in the form of metaphors) relating to Taoist meditation and breathing.