Kan is one of the eight trigrams (bagua) of the Yijing. It is composed of a single yang line at the centre between two broken yin lines, and its attribute is Water, the Abysmal, associated with danger, depth, and the flowing that finds its way through any hazard. In the family symbolism it is the Middle Son, and its polarity is yang. Its associated element is Water, and in the Later Heaven arrangement of the bagua its direction is due north, the place of winter and midnight. 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 Kan, the abyss of water, is the natural counterpart of the bright and clinging fire of Li.
In the Earlier Heaven or Fu Xi arrangement, an older and more static ordering than the Later Heaven sequence used for compass direction above, Kan stands in the west rather than the north. Kan's abyss has a practical afterlife in feng shui, appearing with the other seven trigrams around the rim of the small octagonal bagua mirror hung to deflect unfavourable influences, and again around the outer rings of the Luopan, the compass used to orient buildings, where the Later Heaven sequence generally governs directional and spatial judgement while the Earlier Heaven sequence is reserved for the more cosmological branches of the practice.
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