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Ian Stewart
Ian Nicholas Stewart FRS CMath FIMA is a British mathematician and a popular-science and science-fiction writer. He is Emeritus Professor of Mathematics at the University of Warwick, England. --Wikipedia
Judgement Day
Marjorie Daw is a librarian defending her public library from a local council seeking to tear it down. Meanwhile, in Roundworld, the God of Evolution faces the God of Creation in a Pratchett-esque theological lawsuit over who really made the universe. The alternating fiction and science chapters in the fourth and final Science of Discworld book tackle the relationship between religion and science — why they conflict, where they don't, and what each is actually for.
Judgement Day (The Science of Discworld IV) tackles the relationship between religion and science, framed through a Discworld legal battle over the creation of Roundworld. The science chapters address the history and philosophy of the creation/evolution debate.
Yes. Judgement Day (2013) is the fourth and final Science of Discworld book. It was published by Ebury Press.
Terry Pratchett, Ian Stewart, and Jack Cohen. At the time of writing Pratchett was already living with posterior cortical atrophy.
Marjorie Daw is a new character introduced in Judgement Day — a librarian fighting to save her library from closure. She was later used in the Discworld series itself in The Shepherd's Crown.