The ninth hexagram, Xiao Xu ("The Taming Power of the Small"), places Xun (Wind) above Qian (Heaven). Wind moving across the sky can restrain the great creative force only gently and for a time, the image of a small power holding back a large one. It follows Union in the King Wen sequence.
Xiao Xu stands fifth of 64 in the xiantian, or Earlier Heaven, arrangement, the binary ordering devised by Shao Yong in the eleventh century and ascribed to Fu Xi, close to the head of that sequence though ninth in the King Wen order used above; it was this ordering that the Jesuit Joachim Bouvet sent from Beijing in 1701 to Gottfried Wilhelm Leibniz, who recognized its broken and unbroken lines as his own binary 0 and 1.
Read from the bottom, the six lines of Small Taming run yang, yang, yang, yin, yang, yang. A later interpretive layer absent from the original Zhou Yi, the nuclear hexagram (hu gua), treats lines two through four as a lower trigram and lines three through five as an upper one; here they combine as Li over Dui, forming hexagram 38, Opposition (Kui), a hidden figure first associated with the Han-dynasty scholar Jing Fang, whose Yijing commentary of the first century BCE is credited with the earliest appearance of nuclear trigrams. Small Taming's King Wen partner is hexagram 10, Treading (Lu); most of the sixty-four pair this way, related by turning the whole figure upside down, while the eight hexagrams built from a single doubled trigram pair instead by inverting every line. Mawangdui (1973) orders hexagrams by trigram, not King Wen; names here follow Wilhelm and Baynes, 1950, not Legge, 1882.