Tim and Steve,
This is an interesting can of worms! I’m enjoying the discussion.
Regarding something you said, Steve: ‘I think adding the issue of the "wu xing" is also important. "Advance", retreat, look left and gaze right are also close to "directions." But, of course, they still wouldn't be as "pure" as compass point directions.’
Sarah Allan, in her book, _The Shape of the Turtle: Myth, Art, and Cosmos in Early China_, writes of early enunciations of this notion and how it’s often called something like “the five directions.” But she points out the semantic problem of referring to the “middle” as a “direction.” Of course it’s not a direction. In taiji theory, this “middle” is also sometimes translated as one of the “five directions,” but that just doesn’t make sense, does it? It’s also more properly called, “central equilibrium” (zhong ding). But this raises another semantic problem. Can “central equilibrium” be called a “posture?” Ideally, central equilibrium is operative even in movement, but “posture” says to me something static rather than dynamic. By the same token, can “advancing,” “retreating,” “look left,” “gaze right” be called postures? I don’t think so. That’s why I’ve come to think that translating “Shisan Shi” as “Thirteen Postures” is flawed. The Chinese character “shi” has a range of meaning that includes “posture” but that encompasses much more, including a meaning of “disposition” or “situation.” So that’s why I propose a rendering of “Thirteen Efficacious Dispositions” for the traditional notions of peng, lu, ji, an, cai, lie, zhou, kao, jinbu, tuibu, zougu, youpan, zhongding.