Secrecy Led to the Loss of Chinese Technological Achievements

While these state records survive, most of the ancient Chinese literature on astronomy has disappeared. Because astronomy was so state-oriented, so security-bound, and so secret, the old astronomy books have left few traces. By contrast, the early books on mathematics, which were used by merchants, directors of public works, and military commanders, have survived in considerable numbers. Repeated imperial edicts enforced state security for calendrical science, astronomy, and astrology. In A.D. 840, for example, when the empire had recently been disturbed by the appearance of several comets, the Emperor ordered all observers in the imperial observatory to keep their business secret. “If we hear of any intercourse between the astronomical officials or their subordinates and officials of other government departments or miscellaneous common people, it will be regarded as a violation of security regulations which should be strictly adhered to. From now onwards, therefore, the astronomical officials are on no account to mix with civil servants and common people in general. Let the Censorate look to it.” The security concerns which so notoriously plagued atomic research centers at Los Alamos and Harwell in World War II had their Chinese antecedents. The famous Heavenly Clockwork of Su Sung could not have been constructed if Su Sung had not been a high imperial official authorized to help the Emperor view the astrological destinies. This explains, too, why, within a few years, Su Sung’s spectacular achievement had become only a dim legend. If Su Sung had built his clockwork not for the private garden of a Chinese emperor but for a European town hall, he would have been hailed as a heroic public benefactor. His work would have become a monument to civic pride—the object of widespread emulation.

The state guarded its understanding of Astronomy and Time-Keeping so that history has little record of the details of how advanced it was. In contrast, public science is known and revered by historians.