08 AUG 2013 by ideonexus

 Secrecy Led to the Loss of Chinese Technological Achievem...

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...
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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.