• Claudius Ptolemy’s great work on astronomy, now known by its Arabic name. Written in the second century AD, it remained the classic text on astronomy until the time of Copernicus, a record unlikely to be matched by modern works. In The Sleepwalkers, the standard history of cosmological thinking, Arthur Koestler complains that its dominance was caused by the whole science of astronomy being sent up a cul-de-sac for one and a half millennia.