Waxing and Waning
Carried by twelve chapters
In the constellation
Waxing and waning is the law that fullness cannot last: the sun at its zenith turns toward setting, and the moon nearly full stands at the moment before reversal. 15 Ch'ien - Modesty states it plainly:
It is the law of heaven to make fullness empty and to make full what is modest; when the sun is at its zenith, it must, according to the law of heaven, turn toward its setting, and at its nadir it rises toward a new dawn.
The moon supplies the oracle's precision instrument. The formula recurs at the point of maximal favorable tension: in 09 Hsiao Ch'u - The Taming Power of the Small, "The moon is nearly full. If the superior man persists, Misfortune comes," for "When it is full and directly opposite the sun, its waning is inevitable." In 54 Kuei Mei - The Marrying Maiden, "The moon that is nearly full Brings good fortune," the modest princess "just as the moon, before it is quite full, does not directly face the sun." In 61 Chung Fu - Inner Truth, "The moon nearly at the full" calls for the humility "of the moon when it is not yet quite full." Favor lives just short of fullness; fullness itself is the turning.
55 Fêng - Abundance (Fullness) is bracketed by transience on every side. Its Judgment commands:
Be not sad.
Be like the sun at midday.
precisely because midday cannot be held: "Such a time of abundance is usually brief." And the paired endings build the law into the architecture of the book itself. 63 Chi Chi - After Completion warns "At the beginning good fortune. At the end disorder," since at perfect equilibrium "any movement may cause order to revert to disorder," while 64 Wei Chi - Before Completion closes the book not on completion but on its eve, a spring leading out of winter. The sequence ends waxing, not full.
The Taoist parallel is Tao Te Ching 9, fill a cup to the brim and it spills, whet a blade too fine and it dulls; and chapter 40, reversal is the movement of the Tao. Wilhelm's commentary on 32 Hêng - Duration quotes Lao Tzu directly: "If we wish to compress something, we must first let it fully expand."