Despite a resurgence in popularity, horoscopes are generally considered to be pseudoscience today - but they were once a cutting-edge scientific tool. In this ingenious work of history, data scientist Alexander Boxer examines a treasure trove of esoteric classical sources to expose the deep imaginative framework by which - for millennia - we made sense of our fates. Astrology, he argues, was the ancient world''s most ambitious applied mathematics problem, a grand data-analysis enterprise sustained by some of history''s most brilliant minds, from Ptolemy to al-Kindi to Kepler.A Scheme of Heaven explores the wonderful subtleties of astrological ideas. Telling the stories of their inventors and most influential exponents, Boxer puts them through their paces using modern data sets - finding that the methods of today''s scientists are often uncomfortably close to those of astrology''s ancient sages.