道，可道也，非恒道也；
The divine law that can be told is not the eternal law;
名，可名也，非恒名也。
The name that can be named is not the eternal name.
无，名万物之始也，
wu, is the origin of all creations,
有，名万物之母也。
you, is the mother of all creations.
故恒无欲也，以观其眇。
Free from desire/expectation, you realize the mystery.
恒有欲也，以观其所噭。
Caught in desire, you see only the manifestions.
两者同出，异名同谓。
Yet mystery and manifestions, arise from the same source,
but have different names.
玄之又玄，众眇之门。
Mystery with mystery, the gateway to all understanding.

恒 is used in the Mawangdui silk manuscript, while 常 is used in the standard text. The story behind is that there was an emperor called 刘恒. His name couldn’t be spoken of or written down, so every 恒 in a text was changed to another word.

Chapter 1 relates to the Yi Jing hexagram 3, ䷂, 屯 (zhūn or tun), which means "accumulating," "beginning," or "sprouting."