He Tu Diagram

The He Tu, the Yellow River Chart, enters the record beside its twin. The Great Appendix of the Yijing says simply that the He gave forth the map and the Lo gave forth the writing, and the sages took them as pattern; tradition supplies the scene, a dragon-horse rising from the Yellow River before the sage Fu Xi, the markings on its flank revealing the numbers of heaven and earth. The diagram those numbers form is a picture of balance. The numbers one to ten stand in ten clusters of dots, paired by direction: one and six to the north, two and seven to the south, three and eight to the east, four and nine to the west, five and ten at the centre. Odd numbers are heaven's, drawn as white dots; even numbers are earth's, drawn as black; and each direction holds a generating number and a completing number that differ by five.

Later cosmology bound the pairs to the five phases, water in the north, fire in the south, wood in the east, metal in the west and earth at the centre, so that the chart became a map of the world's workings at rest. Where the Lo Shu, with its restless magic sums, was read as the order of change and circulation, the He Tu was read as the prior order, the numbers of heaven and earth in generative embrace before movement begins. The pairing of the two diagrams, stillness and change, plan and process, became one of the organising polarities of Chinese cosmological thought.

The He Tu's dots look timeless, but their history is precise, and Richard Smith's study of the Yijing's career in Chinese thought tells it candidly. The names He Tu and Lo Shu are ancient, attested in the classics; the familiar diagrams of white and black dots are another matter. They surface in the Song dynasty, transmitted through a lineage of diagram masters that tradition traces back to the Daoist recluse Chen Tuan, and they were canonised when Zhu Xi, the great synthesizer of Neo-Confucianism, set them at the head of his edition of the Yijing. From that placement flowed centuries of tushu, diagram learning: cosmologists read the He Tu's pairs as the generation of the five phases, matched its numbers against the trigrams, and built from the two charts a complete numerical metaphysics. The confidence lasted until the Qing, when the philologist Hu Wei subjected the diagrams to withering documentary criticism, arguing that the dot figures were Song constructions with no warrant in the ancient texts, and that a millennium of speculation had been raised on a medieval drawing.

Modern scholarship has largely sustained the philology while keeping the larger point: whatever the age of the drawings, the habit of thinking they crystallise, that heaven and earth have numbers and that their pairing can be diagrammed, runs deep and early in Chinese thought. The He Tu is thus doubly instructive: a genuine ancient name, a medieval image, and a standing lesson in how traditions furnish their own antiquity.