We believe that Confucius was a real person because the extant textual tradition provides ample evidence that he was. There is some biographical information about “Laozi” as well (Lao Dan, or Li Er), but much less is known about him than Confucius. Additionally, the scholarly consensus on the Daodejing is that it was not written by a single author, but is instead a compilation. This calls into question whether or not the person Lao Dan is in any way associated with “Laozi,” author of the Daodejing. The author of the text is mythical, however I am more than willing to believe that Lao Dan was a real person.

In the past, I’ve talked a bit about the question of whether or not “Laozi” was a real person, and I think you may find that post helpful.