The double principle has been seen operating in the imitative singularities of hobbyhorse riders, in the double relation of impressions and ideas, and in the hypallages and mirrorings of Shandean narrative. The reciprocal play of accident and design common to all these examples has its icon in Hogarth's joint-figure of the country dance, where the cross-section or outline stands in the same relation to the map of the whole set as the hobbyhorsical trifle to its history, as the single impression to the associative structure with which it acts and reacts, and as the minute circumstance of a narrative to the structure that accommodates a specular self-reading. In these analogous pairings, the cross-sectional element is incomplete, contingent, unpredictable and trivial, while the map represents the possibility of order and symmetry. The more this possibility is explored, the more the loose accidents of the upper box are turned into narrative, articulated into a series of necessary connexions that begins to read like a story. As well as reflecting the biography of its reader, this story is likely to cross the frontier of literature proper, either as quotation or as figure. The double principle is always most cleverly and effectively manifest in literary form when the natural incompleteness of the cross-section is reflected in a fragment of a text or in a defective archetype. Real imperfections are then matched with splinters of the written – the figures of a consoling rhetoric – rather than being formally completed by literary supplements. In this sense Hogarth's unfinished oilpainting of The Country Dance is more faithful to the schema of his diagrams than the copperplate they actually border.