The fifty-fourth hexagram, Gui Mei ("The Marrying Maiden"), places Zhen (Thunder) above Dui (Lake). Thunder stirring above the joyous lake gives the image of movement prompted by pleasure, here the younger sister entering a marriage in a subordinate position. It follows Development in the King Wen order, contrasting proper courtship with an irregular union.
Gui Mei holds a further position in the xiantian, or Earlier Heaven, arrangement, the binary ordering devised by Shao Yong in the eleventh century and traditionally ascribed to Fu Xi: twelfth of 64, apart from its fifty-fourth place in the King Wen sequence above. This was the Fu Xi 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 The Marrying Maiden run yang, yang, yin, yang, yin, yin. 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 Kan over Li, forming hexagram 63, After Completion (Ji Ji), 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. The Marrying Maiden's King Wen partner is hexagram 53, Development (Jian); 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.