Laozi is not a name at all: it means old teacher
The founding sage of Taoism is known by an honorific, Laozi, roughly venerable master, in the same pattern as Kongzi for Confucius. Whether a real person stood behind the title is still argued. Yet bamboo slips buried around 300 BC show that much of the Tao Te Ching already existed by then.
Tradition names him Li Er, also Lao Dan, a keeper of archives at the Zhou court in the 6th-century BC state of Chu and an older contemporary of Confucius. Li doubles as the word for plum, and one legend ties his birth to a plum tree; Dan is usually glossed as long-eared, and the character in Er means ear. He is also recorded with the courtesy name Boyang.
Early texts, including the Zhuangzi and the Confucian Liji, describe meetings between Lao Dan and Confucius, with Confucius citing him on ritual. The scholar Alan Chan argues that because Lao Dan appears favourably in both Confucian and Taoist writings, he is unlikely to have been invented simply to score points, and a historical teacher later honoured as Laozi is plausible.
In the 1920s and 1930s many scholars moved his dates to the 4th or 3rd century BC. Wing-tsit Chan wrote in 1963 that the idea he never existed was no longer seriously entertained, while William Boltz thought the traditional figure probably fictional. A. C. Graham, sceptical that one author wrote the whole book, still traced the Confucius meeting story back to at least the 4th century BC.
The Guodian slips changed the debate. Buried around 300 BC, they hold about 2,000 characters matching roughly forty percent of the received text, spread across material that later became thirty-one chapters. Moss Roberts suggests this core may go back to Lao Dan with other parts added later, while Edward Shaughnessy cautions that the slips alone cannot settle how the book was composed. The Tang dynasty claimed Laozi as an ancestor, the huge Li clan honours him as a forebear, and religious Taoism eventually treated him as a god, Laojun.
Source: Laozi
