Judgment Day

December 14, 2015
Half popular science essay and half fantasy tale, the final installment of the enjoyable Science of Discworld series sums up by updating topics from previous books while exploring the nature of our universe and the psychology of human belief. Ever since the wizards of Discworld's Unseen University accidentally created "Roundworld"âaka Earthâthey've been befuddled and fascinated by this strange world that "swims through space" without the benefit of resting on four elephants and a giant turtle (unlike the perfectly normal, and quite flat, Discworld). After six years of protecting Roundworld from destruction in its own space, the wizards now face a Discworld-born threat: the Omnian church, which is certain that Discworld is spherical, has laid claim to Roundworld as vindication of their faith. The wizards' story chapters frame essays on science-related topics such as the Big Bang, particle physics, and the Anthropic Principle, as well as belief systems, creation myths, and the Flat Earth Society. While the fantasy frame here is weaker than those in previous books, the investigations of the late Pratchett's pragmatic wizardsâwhen they aren't distracted by the last chocolate biscuit on the tea trayâprovide a firm foundation for science coverage from mathematician Stewart and zoologist Cohen, reminding readers that "scientific revolutions don't change the universe. They change how humans interpret it." Agent: Colin Smythe, Colin Smythe Limited.