The Science of Discworld III: Darwin's Watch is a book set on the Discworld, by Terry Pratchett, Ian Stewart and Jack Cohen. It is the sequel to The Science of Discworld and The Science of Discworld II: The Globe and it's followed by The Science of Discworld IV: Judgement Day. As with the first two volumes, the book alternates between a Discworld story and a serious scientific discussion. The title refers to William Paley's watchmaker analogy and Richard Dawkins' subsequent description of evolution as the Blind Watchmaker.