The Liji, the Book of Rites, has a chapter called Yu Zao that governs what a
gentleman wears at court, and it is unexpectedly detailed about jade. Four of its lines do
most of the work.
The first is the one every Chinese schoolchild half-remembers: a gentleman, without good
reason, does not let jade leave his body, because a gentleman likens his virtue to jade.
The second makes it a requirement rather than a habit: every belt must carry jade pendants,
and the only exception is mourning.
The third is where it gets strange. The gentlemen of antiquity, the text says, must wear
jade, and it specifies the sound: the right-hand pendants give two particular notes of the
scale and the left-hand pendants give two others. The pendants were tuned. Two clusters of
hanging jade, on the two sides of the body, pitched to different degrees of the pentatonic
scale, so that a person walking was producing a chord.
And the fourth line explains what all of that is for. Move at a walk to one piece of court
music, the chapter instructs, and at a faster pace to another; turn a full circle and the
arc should be a true circle; turn a corner and the angle should be square; bow going
forward, straighten coming back, and then the jade will ring properly. When he walks, it
concludes, the jade pendants sound, and by this means a crooked thought finds no way in.
Read that again, because it is one of the most quietly extraordinary sentences in Chinese
ritual writing. The jade is a feedback device. Walk with the right rhythm and it chimes
cleanly. Hurry, slouch, cut a corner, fidget, and the sound goes wrong, audibly, in front
of everyone. You are wearing an instrument that reports on your self-command, and the
argument is that a person occupied with keeping the chime right has no attention left over
for a bad idea.
Nobody carries a tuned pendant cluster now. But the logic under it is still the thing
people mean when they say jade is about character rather than luck, and it is the reason a
jade bangle is given to a young person rather than bought by them.