Yet another instance of hackerdom's peculiar attraction to mystical references -- a common humorous way of making exclusive statements about a class of things. The template is from the Tao te Ching: "The Tao which can be spoken of is not the true Tao." The implication is often that the X is a mystery accessible only to the enlightened. See the {trampoline} entry for an example, and compare {has the X nature}.
[glossary]
[Reference(s) to this entry by made by: {has the X nature}]