It is Zheng Xuan (127–200), more than any other commentator, to whom we owe our current understanding of the Confucian Classics – Zheng Xuan, his subcommentators, Kong Yingda (574–648), and Jia Gongyan (fl. 637), who canonised his readings in the early Tang (618–907). Zheng Xuan made mistakes, however, and this chapter offers a case in point: the calculation of physically impossible target geometries for the royal archery meet reputedly held in the Western Zhou (1045–771 BCE), the ‘Big Shoot’ (dashe). In transforming the ambiguous language of the Classics into an elaborate mathematics problem with definite quantities, Zheng Xuan neglects to account for the targets being in three dimensions, and his subcommentators supply mathematical proofs for numbers that are ‘flat wrong’. It is not as if they could not have known, I argue, as the Big Shoot was living practice in their respective days, and as Zheng and Kong were trained in mathematics. Faced with this curious dissonance between exegesis, experience, and mathematical training, I suggest that we might better understand the work of the exegete as reconstructing abstract, ideal forms which were necessarily divorced from their reality and for which mathematics suggested itself as the perfect tool.