Although the author of the DDJ is always given as “Lao Zi” or “Lao Tsu” (old spelling), we have no historical proof of his existence. A Chinese court historian named Sima Qian, who lived around 115 BCE, wrote a biography of Lao Zi (literally “old master”, unless Lao is a family name – in which case “master Lao”) that presents three different possible traditions, although the accuracy of any of them is doubtful. The first says that Lao Zi was a contemporary of Confucius (500 BCE). His family name was Li (“plum”), his given name was Er (“ear”), and he was posthumously called Dan (“long ear”). He was an official in the imperial archives, but when the Zhou dynasty began to decline, he decided to leave China. When he reached the northwest border of China, the border guard asked him to write down his teachings, which resulted in a document of about 5000 characters in two sections. Later in the same document, Sima Qian also speculates that Lao Zi may or may not have been Lao Dan (“old long ear”), an advisor to Duke Xian (370 BCE). Finally, Sima Qian says that a man named Lao Laizi (“old returning master”) authored a Daoist book that had 15 parts, was born in the same province as Lao Zi, and also was a contemporary of Confucius. These three accounts are further complicated by reported meetings between Confucius and someone called Lao Dan in various Confucian texts.
References to the DDJ by other ancient Chinese writers indicate that at least some parts of the DDJ were in existence by 300 BCE, and it was being referred to extensively by 250 BCE. One linguistic analysis of the rhyme schemes indicates that it may have originated as early as 450 BCE, and if the DDJ contains the written version of earlier oral traditions, these rhymes may reflect its oldest origins (because rhymes are easier to memorize). Other references and linguistic analyses place its beginnings around perhaps 375-325 BCE, and the earliest known written portions of it (described in the next section) date to about 300 BCE.
So, some parts of the DDJ seem to have first appeared in written form between roughly 350-300 BCE, although its roots could be much older. It certainly existed in some version of its finished form (roughly 5000 characters in 81 chapters) by 200 BCE.
There is also debate on whether the text represents the work of mostly one author, or was added to by different authors over the course of about a century, or was later compiled from different traditions by one person.
The most recent versions of the DDJ are separated into 81 chapters, and two major parts. The first part, consisting of chapters 1-37, primarily discusses Dao, while chapters 38-81 primarily discuss De. Ancient authors referring to the DDJ also speak of versions that are divided into 64, 68, or 72 chapters.
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Different Versions of the DDJ
There are at least six different ancient sources of the text (all dates are approximate) :