The Bagua is a spatial arrangement rather than a single fixed image: eight trigrams, each a stack of three broken or unbroken lines, placed around a central point, most often around a Taijitu, the black and white yin-yang emblem already recorded separately in this atlas. Richard Smith's history of the Yijing describes two standard arrangements that differ structurally rather than as loose variants of one scheme: the Earlier Heaven, or Fuxi, sequence, associated with a cosmological, before-manifestation ordering of the trigrams, and the Later Heaven, or King Wen, sequence, associated with the world of active change and used as the compass-direction basis for most practical feng shui work, place the same eight trigrams in genuinely different positions around the circle, so a Bagua diagram is only meaningful once the reader knows which of the two sequences it is drawing on.
Smith notes that traditional Chinese cosmological texts treat the Earlier Heaven sequence as describing an ideal, pre-manifest cosmic order and the Later Heaven sequence as describing the world of observable change and practical action, a conceptual division that explains why the two arrangements are not treated as competing corrections of one another but as descriptions of two different cosmological registers.