Kun

Kun is one of the eight trigrams (bagua) of the Yijing. It is composed of three broken yin lines, and its attribute is Earth, the Receptive, the pure yin principle of yielding, nourishing, and sustaining, the ground that receives and gives form to what the Creative begins. In the family symbolism it is the Mother, and its polarity is yin. Its associated element is Earth, and in the Later Heaven arrangement of the bagua its direction is southwest, though in the Earlier Heaven arrangement it stands due north at the bottom. Each of the eight trigrams combines with another to form the sixty-four hexagrams of the Yijing. These are the conventions of the Chinese cosmological and divinatory tradition, in which Kun, all yin, is the counterpart and complement of the all-yang Qian.

Kun's Fu Xi position at due north, opposite Qian at due south, gave the pure yin trigram a further afterlife outside Chinese cosmology. In 1701 the Jesuit missionary Joachim Bouvet sent Gottfried Wilhelm Leibniz, from Beijing, a diagram of the Fu Xi ordering of the sixty-four hexagrams; Leibniz, already developing binary arithmetic, recognised that Kun's three broken lines and Qian's three unbroken ones mapped onto his own 0 and 1, and in a paper published in Paris in 1703 he noted, in his own words, that Fu Xi appeared to have anticipated his binary system some four thousand years earlier, all yin and all yang standing at the two poles of the same numerical idea.

Sources Fathoming the Cosmos and Ordering the World: The Yijing (I Ching, or Classic of Changes) and Its Evolution in ChinaRichard J. Smith with The I Ching, or Book of ChangesRichard Wilhelm (trans.); Cary F. Baynes (English trans.), The Five "Confucian" ClassicsMichael Nylan

Kun stands in the north in the Earlier Heaven arrangement attributed to Fuxi, directly opposite Qian in the south, and the two together define the axis on which that whole symmetrical order is built. In the Later Heaven arrangement attributed to King Wen, Kun moves to the southwest, and Qian to the northwest, so the pure yin and pure yang trigrams that anchored the first diagram are pushed to adjacent corners of the second.

That displacement is the single clearest sign that the two arrangements are answering different questions. Earlier Heaven puts heaven and earth on the vertical axis because it is describing an ideal cosmos in balance. Later Heaven is describing the world as it turns, and in a diagram organised by the seasons the trigram of the receiving earth belongs to late summer, when what was planted is being carried and filled out rather than begun.

In the Later Heaven order Kun belongs to the phase Earth, shared with Gen. From the Shuogua it takes the ox among animals, for patient strength under a load, and the belly among the parts of the body, the part that contains and nourishes. In the family scheme Kun is the mother, the trigram of unmixed yin from which each of the three daughters takes its single yin line.

Kun and Qian are the two trigrams that have no mixed lines at all, which is why every other trigram in the system can be described as one of them with a line exchanged.

Sources Fathoming the Cosmos and Ordering the World: The Yijing (I Ching, or Classic of Changes) and Its Evolution in ChinaRichard J. Smith with The I Ching, or Book of ChangesRichard Wilhelm (trans.); Cary F. Baynes (English trans.), The Five "Confucian" ClassicsMichael Nylan