Sir Terence David John "Terry" Pratchett, OBE (28 April 1948 – 12 March 2015) was an English author of fantasy novels, especially comical works. He is best known for his Discworld series of about 40 volumes. Pratchett's first novel, The Carpet People, was published in 1971, and since his first Discworld novel, The Colour of Magic, was published in 1983, he wrote two books a year on average. His 2011 Discworld novel Snuff was at the time of its release the third-fastest-selling hardback adult-readership novel since records began in the UK, selling 55,000 copies in the first three days.
Pratchett, with more than 85 million books sold worldwide in 37 languages, was the UK's best-selling author of the 1990s. He was appointed Officer of the Order of the British Empire (OBE) in 1998 and was knighted for services to literature in the 2009 New Year Honours. In 2001 he won the annual Carnegie Medal for The Amazing Maurice and his Educated Rodents, the first Discworld book marketed for children. He received the World Fantasy Award for Life Achievement in 2010.
In December 2007, Pratchett announced that he was suffering from early-onset Alzheimer's disease. He later made a substantial public donation to the Alzheimer's Research Trust (now Alzheimer's Research UK), filmed a television programme chronicling his experiences with the disease for the BBC, and also became a patron for Alzheimer's Research UK. Pratchett died on 12 March 2015, aged 66.
Pratchett was born on 28 April 1948 in Beaconsfield in Buckinghamshire, England, the only child of David and Eileen Pratchett, of Hay-on-Wye and he attended Holtspur School. His family moved to Bridgwater, Somerset, briefly in 1957, following which he passed his eleven plus exam in 1959, earning a place in High Wycombe Technical High School (now John Hampden Grammar School) where he was a key member of the debating society and wrote stories for the school magazine. Pratchett described himself as a "non-descript student" and, in his Who's Who entry, credits his education to the Beaconsfield Public Library.
His early interests included astronomy. He collected Brooke Bond tea cards about space, owned a telescope and wanted to be an astronomer but lacked the necessary mathematical skills. He developed an interest in reading science fiction and began attending science fiction conventions from about 1963–1964, but stopped when he got his first job a few years later. His early reading included the works of H. G. Wells, Arthur Conan Doyle, and "every book you really ought to read", which he later regarded as "getting an education".
Pratchett published his first short story entitled "Business Rivals" in the High Wycombe Technical School magazine in 1962. It is the tale of a man named Crucible who finds the Devil in his flat in a cloud of sulphurous smoke. "The Hades Business" which was published in the school magazine when he was 13 was published commercially when he was 15.
Pratchett earned five O-levels and started A-level courses in Art, English and History. His initial career choice was journalism and he left school at 17 in 1965 to start working for the Bucks Free Press, where he wrote, amongst other things, several stories for the Children's Circle section under the name Uncle Jim. One of these episodic stories contains named characters from The Carpet People (1971). The stories are currently part of a project by the Bucks Free Press to make them available online. While on day release he finished his A-Level in English and took a proficiency course for journalists.
Pratchett had his writing breakthrough in 1968 when he interviewed Peter Bander van Duren, co-director of a small publishing company, Colin Smythe Ltd. During the meeting, Pratchett mentioned he had written a manuscript, The Carpet People. Colin Smythe Ltd published the book in 1971, with illustrations by Pratchett. The book received strong, if few, reviews and was followed by the science fiction novels The Dark Side of the Sun (1976) and Strata (1981).
After various positions in journalism, in 1980 Pratchett became Press Officer for the Central Electricity Generating Board in an area which covered four nuclear power stations. He later joked that he had demonstrated "impeccable timing" by making this career change so soon after the Three Mile Island nuclear accident in Pennsylvania, US, and said he would "write a book about my experiences, if I thought anyone would believe it".
The first Discworld novel, The Colour of Magic, was published in hardback by Colin Smythe Ltd in 1983. The paperback edition was published by Corgi, an imprint of Transworld, in 1985. Pratchett's popularity increased when the BBC's Woman's Hour broadcast The Colour of Magic as a serial in six parts, and later Equal Rites. Subsequently, the hardback rights were taken by the publishing house Victor Gollancz Ltd, which remained Pratchett's publisher until 1997, and Colin Smythe became Pratchett's agent. Pratchett was the first fantasy author published by Gollancz.
Pratchett gave up working for the CEGB to make his living through writing in 1987, after finishing the fourth Discworld novel, Mort. His sales increased quickly and many of his books occupied top places on the best-seller list. According to The Times, Pratchett was the top-selling and highest earning UK author in 1996. Some of his books have been published by Doubleday, another Transworld imprint. In the US, Pratchett is published by HarperCollins.
According to the Bookseller's Pocket Yearbook (2005), in 2003 Pratchett's UK sales amounted to 3.4% of the fiction market by hardback sales and 3.8% by value, putting him in second place behind J. K. Rowling (6% and 5.6%, respectively), while in the paperback sales list Pratchett came 5th with 1.2% and 1.3% by value (behind James Patterson (1.9% and 1.7%), Alexander McCall Smith, John Grisham, and J. R. R. Tolkien). His sales in the UK alone are more than 2.5 million copies a year.
Pratchett married Lyn Purves in 1968, and they moved to Rowberrow, Somerset, in 1970. Their daughter Rhianna Pratchett, who is also a writer, was born there in 1976. In 1993, the family moved to Broad Chalke, a village west of Salisbury, Wiltshire. He listed his recreations as "writing, walking, computers, life". He described himself as a humanist and was a Distinguished Supporter of the British Humanist Association and an Honorary Associate of the National Secular Society. He was the patron of the Friends of High Wycombe Library. In 2013 he gave a talk at Beaconsfield Library which he had visited as a child and donated the income from the event to it. On a number of occasions he also visited his former school to speak to the students and look around.
Pratchett was well known for his penchant for wearing large, black fedora hats, as seen on the inside back covers of most of his books. His style has been described as "more that of urban cowboy than city gent."
Concern for the future of civilisation prompted him to install five kilowatts of photovoltaic cells (for solar energy) at his house. Having been interested in astronomy since childhood, he had an observatory built in his garden. An asteroid (127005 Pratchett) is named after him.
On 31 December 2008, it was announced that Pratchett was to be knighted (as a Knight Bachelor) in the Queen's 2009 New Year Honours. He formally received the accolade at Buckingham Palace on 18 February 2009. Afterwards he said, "You can't ask a fantasy writer not to want a knighthood. You know, for two pins I'd get myself a horse and a sword." In late 2009, he did make himself a sword, with the help of his friends. He told a Times Higher Education interviewer that “At the end of last year I made my own sword. I dug out the iron ore from a field about 10 miles away – I was helped by interested friends. We lugged 80 kilos of iron ore, used clay from the garden and straw to make a kiln, and lit the kiln with wildfire by making it with a bow.' Colin Smythe, his long-term friend and agent, donated some pieces of meteoric iron – ‘thunderbolt iron’ has a special place in magic and we put that in the smelt, and I remember when we sawed the iron apart it looked like silver. Everything about it I touched, handled and so forth ... And everything was as it should have been, it seemed to me.”
In August 2007, Pratchett was misdiagnosed as having had a minor stroke in 2004 or 2005, which doctors believed had damaged the right side of his brain. While his motor skills were affected, the observed damage had not impaired his ability to write. On 11 December 2007, Pratchett posted online that he had been newly diagnosed with early-onset Alzheimer's disease, which had been responsible for the "stroke". He had a rare form of the disease, posterior cortical atrophy (PCA), in which areas at the back of the brain begin to shrink and shrivel.
Describing the diagnosis as an "embuggerance" in a radio interview, Pratchett appealed to people to "keep things cheerful" and proclaimed that "we are taking it fairly philosophically down here and possibly with a mild optimism." He stated he felt he had time for "at least a few more books yet", and added that while he understood the impulse to ask "is there anything I can do?", in this case he would only entertain such offers from "very high-end experts in brain chemistry." Discussing his diagnosis at the Bath Literature Festival in early 2008, Pratchett revealed that he by then found it too difficult to write dedications when signing books. In his later years Pratchett wrote by dictating to his assistant, Rob Wilkins, or by using speech recognition software.
In March 2008, Pratchett announced he would donate US$1,000,000 (about £494,000) to the Alzheimer's Research Trust, and that he was shocked "to find out that funding for Alzheimer's research is just 3% of that to find cancer cures." He said: "I am, along with many others, scrabbling to stay ahead long enough to be there when the Cure comes along."
In April 2008, Pratchett worked with the BBC to make a two-part documentary series about his illness, Terry Pratchett: Living With Alzheimer's. The first part was broadcast on BBC Two on 4 February 2009, drawing 2.6m viewers and a 10.4% audience share. The second, broadcast on 11 February 2009, drew 1.72m viewers and a 6.8% audience share. The documentary won a BAFTA award in the Factual Series category. Pratchett also made an appearance on The One Show on 15 May 2008, talking about his condition. He was the subject and interviewee of the edition of 20 May 2008 of On the Ropes (Radio 4), discussing Alzheimer's and how it had affected his life.
On 8 June 2008, news reports indicated that Pratchett had an experience which he described as: "It is just possible that once you have got past all the gods that we have created with big beards and many human traits, just beyond all that, on the other side of physics, there just may be the ordered structure from which everything flows" and "I don't actually believe in anyone who could have put that in my head". He went into further detail on Front Row, in which he was asked if this was a shift in his beliefs: "A shift in me in the sense I heard my father talk to me when I was in the garden one day. But I'm absolutely certain that what I heard was my memories of my father. An engram, or something in my head...This is not about God, but somewhere around there is where gods come from."
On 26 November 2008, Pratchett met the Prime Minister Gordon Brown and asked for an increase in dementia research funding. From August 2008, Pratchett tested a prototype device to address his condition. Despite some apparent improvements, the ability of the device to alter the course of the illness has been met with scepticism from Alzheimer's researchers.
In an article published mid-2009, Pratchett stated that he wished to die by assisted suicide (although he disliked that term) before his disease progressed to a critical point. He later said he felt "it should be possible for someone stricken with a serious and ultimately fatal illness to choose to die peacefully with medical help, rather than suffer."Pratchett was selected to give the 2010 BBC Richard Dimbleby Lecture, entitled Shaking Hands With Death, broadcast on 1 February 2010. Pratchett introduced his lecture on the topic of assisted death, but the main text was read by his friend Tony Robinson because Pratchett's condition made it difficult for him to read. In June 2011 Pratchett presented a one-off BBC television documentary, Terry Pratchett: Choosing to Die, about assisted suicide. It won the Best Documentary award at the Scottish BAFTAs in November 2011.
In September 2012 Pratchett stated: "I have to tell you that I thought I’d be a lot worse than this by now, and so did my specialist." In the same interview, he stated that the cognitive part of his mind was "untouched" and his symptoms were physical (normal for PCA). However, in July 2014 he cancelled his appearance at the biennial International Discworld Convention, saying: "the Embuggerance is finally catching up with me, along with other age-related ailments".
Pratchett died at his home on the morning of 12 March 2015 from his Alzheimer's, according to his publisher. The Telegraph reported an unidentified source as saying that despite his previous discussion of assisted suicide, his death had been natural. After Pratchett's death, his assistant, Rob Wilkins, wrote from the official Terry Pratchett Twitter account:
Terry took Death's arm and followed him through the doors and on to the black desert under the endless night.
The use of small capitals is a reference to how the character of Death speaks in Pratchett's works.
Many public figures paid tribute following Pratchett's death, including British Prime Minister David Cameron and the comedian Ricky Gervais, and authors including Nick Harkaway, Ursula Le Guin, Terry Brooks, Margaret Atwood, George R. R. Martin, and Neil Gaiman. Pratchett was memorialised in a graffito in East London, and the video game company Frontier Developments added a space station to Elite: Dangerous named "Pratchett's Disc". Users of the social news site Reddit organised a tribute by which an HTTP header, "X-Clacks-Overhead: GNU Terry Pratchett", is added to a site's responses, a reference to the Discworld novel Going Postal.
Pratchett's humanist funeral service was held on 25 March 2015.
Pratchett started to use computers for writing as soon as they were available to him. His first computer was a Sinclair ZX81; the first computer he used properly for writing was an Amstrad CPC 464, later replaced by a PC. Pratchett was one of the first authors routinely to use the Internet to communicate with fans, and was a contributor to the Usenet newsgroup alt.fan.pratchett from 1992. However, he did not consider the Internet a hobby, just another "thing to use". He had many computers in his house, with a bank of six monitors rigged up to ease writing. When he travelled, he always took a portable computer with him to write.
His experiments with computer upgrades are reflected in Hex.
Pratchett was also an avid video game player, and collaborated in the creation of a number of game adaptations of his books. He favoured games that are "intelligent and have some depth", citing Half-Life 2 and fan missions from Thief as examples. Additionally, he played Oblivion, which he described as "wonderful", and used many of its non-combat-oriented, fan-made mods. He is also said to have enjoyed playing the first Tomb Raider game.
Pratchett had a fascination with natural history that he referred to many times, and he owned a greenhouse full of carnivorous plants.
In 1995, a fossil sea-turtle from the Eocene epoch of New Zealand was named in honour of him Psephophorus terrypratchetti by the palaeontologist Richard Köhler.
Pratchett was a trustee for the Orangutan Foundation UK but was pessimistic about the animal's future. Following Pratchett's lead, fan events such as the Discworld Conventions have adopted the Orangutan Foundation as their nominated charity, which has been acknowledged by the foundation. One of Pratchett's most popular fictional characters, the Librarian of the Unseen University's Library, is a wizard who was transformed into an orangutan in a magical accident and decides to remain in that condition as it is so convenient for his work.
Pratchett had an observatory in his back garden and was a keen astronomer from childhood. He made an appearance on the BBC programme The Sky at Night.
Pratchett sponsored a biennial award for unpublished science fiction novelists, the Terry Pratchett First Novel Award. The prize is a publishing contract with his publishers Transworld. In 2011 the award was won jointly by David Logan for Half Sick of Shadows and Michael Logan for Apocalypse Cow. In 2013 the award was won by Alexander Maskill for The Hive.
Pratchett drinking Guinness shortly after receiving an honorary degree from the University of Dublin in 2008
Pratchett received a knighthood for "services to literature" in the 2009 UK New Year Honours list. He was previously appointed Officer of the Order of the British Empire, also for "services to literature", in 1998. Following this, Pratchett commented in the Ansible SF/fan newsletter, "I suspect the 'services to literature' consisted of refraining from trying to write any," but added, "Still, I cannot help feeling mightily chuffed about it."
Pratchett was the British Book Awards' 'Fantasy and Science Fiction Author of the Year' for 1994.
Pratchett won the British Science Fiction Award in 1989 for his novel, Pyramids, and a Locus Award for Best Fantasy Novel in 2008 for Making Money.
Pratchett was awarded ten honorary doctorates: University of Warwick in 1999, the University of Portsmouth in 2001, the University of Bath in 2003, the University of Bristol in 2004, Buckinghamshire New University in 2008, the University of Dublin in 2008, Bradford University in 2009, University of Winchester in 2009, The Open University in 2013 for his contribution to Public Service and his last, from the University of South Australia, in May 2014.
Pratchett won the 2001 Carnegie Medal from the British librarians, recognising The Amazing Maurice and His Educated Rodents as the year's best children's book published in the UK.
Night Watch won the 2003 Prometheus Award for best libertarian novel.
In 2003, BBC conducted The Big Read to identify the "Nation's Best-loved Novel" and finally published a ranked list of the "Top 200". Pratchett's highest-ranking novel was Mort, number 65, but he and Charles Dickens were the only authors with five in the Top 100 (four of his were from the Discworld series). He also led all authors with fifteen novels in the Top 200.
Three of the four Discworld novels that centre on the "trainee witch" Tiffany Aching won the annual Locus Award for Best Young Adult Book in 2004, 2005 and 2007.
In 2005, Going Postal was shortlisted for the Hugo Award for Best Novel; however, Pratchett recused himself, stating that stress over the award would mar his enjoyment of Worldcon.
Pratchett received the NESFA Skylark Award in 2009 and the World Fantasy Award for Life Achievement in 2010. In 2011 he won Margaret A. Edwards Award from the American Library Association, a lifetime honour for "significant and lasting contribution to young adult literature". The librarians cited nine Discworld novels published from 1983 to 2004 and observed that "Pratchett’s tales of Discworld have won over generations of teen readers with intelligence, heart, and undeniable wit. Comic adventures that fondly mock the fantasy genre, the Discworld novels expose the hypocrisies of contemporary society in an intricate, ever-expanding universe. With satisfyingly multilayered plots, Pratchett's humor honors the intelligence of the reader. Teens eagerly lose themselves in a universe with no maps."
He was made an adjunct Professor in the School of English at Trinity College Dublin in 2010, with a role in postgraduate education in creative writing and popular literature.
I Shall Wear Midnight won the 2010 Andre Norton Award for Young Adult Science Fiction and Fantasy presented by the Science Fiction and Fantasy Writers of America (SFWA) as a part of the Nebula Award ceremony.
Pratchett's Discworld novels have led to dedicated conventions, the first in Manchester in 1996, then worldwide, often with the author as guest of honour. Publication of a new novel was sometimes accompanied by an international book signing tour; queues were known to stretch outside the bookshop as the author continued to sign books well after the intended finishing time. His fans were not restricted by age or gender, and he received a large amount of fan mail from them. Pratchett enjoyed meeting fans and hearing what they think about his books, saying that since he was well paid for his novels, his fans were "everything" to him.
Pratchett said that to write, you must read extensively, both inside and outside your chosen genre and to the point of "overflow". He advised that writing is hard work, and that writers must "make grammar, punctuation and spelling a part of your life." However, Pratchett enjoyed writing, regarding its monetary rewards as "an unavoidable consequence", rather than the reason for writing.
Although during his early career he wrote for the sci-fi and horror genres, Pratchett later focused almost entirely on fantasy, and said: "It is easier to bend the universe around the story." In the acceptance speech for his Carnegie Medal he said: "Fantasy isn't just about wizards and silly wands. It's about seeing the world from new directions", pointing to J. K. Rowling's Harry Potter novels and J. R. R. Tolkien's The Lord of the Rings. In the same speech, he acknowledged benefits of these works for the genre.
Pratchett believed he owed "a debt to the science fiction/fantasy genre which he grew up out of" and disliked the term "magical realism" which, he said, is "like a polite way of saying you write fantasy and is more acceptable to certain people ... who, on the whole, do not care that much." He expressed annoyance that fantasy is "unregarded as a literary form", arguing that it "is the oldest form of fiction"; he described himself as "infuriated" when novels containing science fiction or fantasy ideas were not regarded as part of those genres. He debated this issue with novelist A. S. Byatt and critic Terry Eagleton, arguing that fantasy is fundamental to the way we understand the world and therefore an integral aspect of all fiction.
On 31 July 2005, Pratchett criticised media coverage of Harry Potter author J. K. Rowling, commenting that certain members of the media seemed to think that "the continued elevation of J. K. Rowling can be achieved only at the expense of other writers". Pratchett later denied claims that this was a swipe at Rowling, and said that he was not making claims of plagiarism, but was pointing out the "shared heritage" of the fantasy genre. Pratchett also posted on the Harry Potter newsgroup about a media-covered exchange of views with her.
Pratchett is known for a distinctive writing style that included a number of characteristic hallmarks. One example is his use of footnotes, which usually involve a comic departure from the narrative or a commentary on the narrative, and occasionally have footnotes of their own.
Pratchett had a tendency to avoid using chapters, arguing in a Book Sense interview that "life does not happen in regular chapters, nor do movies, and Homer did not write in chapters", adding "I'm blessed if I know what function they serve in books for adults." However, there have been exceptions; Going Postal and Making Money and several of his books for younger readers are divided into chapters. Pratchett offered explanations for his sporadic use of chapters; in the young adult titles, he said that he must use chapters because '[his] editor screams until [he] does', but otherwise felt that they were an unnecessary 'stopping point' that got in the way of the narrative.
Characters, place names, and titles in Pratchett's books often contain puns, allusions and culture references. Some characters are parodies of well-known characters: for example, Pratchett's character Cohen the Barbarian, also called Ghengiz Cohen, is a parody of Conan the Barbarian and Genghis Khan, and his character Leonard of Quirm is a parody of Leonardo da Vinci.
Another hallmark of his writing was the use of capitalised dialogue without quotation marks, used to indicate the character of Death communicating telepathically into a character's mind. Other characters or types of characters were given similarly distinctive ways of speaking, such as the auditors of reality never having quotation marks, Ankh-Morpork grocers never using punctuation correctly, and golems capitalising each word in everything they say. Pratchett also made up a new colour, octarine, a 'fluorescent greenish-yellow-purple', which is the eighth colour in the Discworld spectrum—the colour of magic. Indeed, the number eight itself is regarded in the Discworld as being a magical number; for example, the eighth son of an eighth son will be a wizard, and his eighth son will be a "sourcerer" (which is one reason why wizards are not allowed to have children).
Discworld novels often included a modern innovation and its introduction to the world's medieval setting, such as a public police force (Guards! Guards!), guns (Men at Arms), submarines (Jingo), cinema (Moving Pictures), investigative journalism (The Truth), the postage stamp (Going Postal), modern banking (Making Money), and the steam engine (Raising Steam). The "clacks", the tower-to-tower semaphore system that sprang up in later novels, is a mechanical optical telegraph (used in Napoleon's Era successfully) before wired electric telegraph chains, with all the change and turmoil that such an advancement implies. The resulting social upheaval driven by these changes serves as the setting for the main story.
Pratchett made no secret of outside influences on his work: they were a major source of his humour. He imported numerous characters from classic literature, popular culture and ancient history, always adding an unexpected twist. Pratchett was a crime novel fan, which was reflected in frequent appearances of the Ankh-Morpork City Watch in the Discworld series. Pratchett was an only child, and his characters are often without siblings. Pratchett explained, "In fiction, only-children are the interesting ones".
Pratchett's earliest inspirations were The Wind in the Willows by Kenneth Grahame, and the works of Isaac Asimov and Arthur C. Clarke. His literary influences have been P.G. Wodehouse, Tom Sharpe, Jerome K. Jerome, Roy Lewis, Alan Coren, G. K. Chesterton, and Mark Twain.
While Pratchett's UK publishing history remained quite stable, his relationships with international publishers were turbulent (especially in America). He changed German publishers after an advertisement for Maggi soup appeared in the middle of the German-language version of Pyramids.
Pratchett began writing the Discworld series in 1983 to "have fun with some of the cliches" and it is a humorous and often satirical sequence of stories set in the colourful fantasy Discworld universe. The series contains various story arcs (or sub-series), and a number of free-standing stories. All are set in an abundance of locations in the same detailed and unified world, such as the Unseen University and 'The Drum/Broken Drum/Mended Drum' public house in the twin city Ankh-Morpork, or places in the various continents, regions and countries on the Disc. Characters and locations reappear throughout the series, variously taking major and minor roles.
The Discworld itself is described as a large disc resting on the backs of four giant elephants, all supported by the giant turtle Great A'Tuin as it swims its way through space. The books are essentially in chronological order, and advancements can be seen in the development of the Discworld civilisations, such as the creation of paper money in Ankh-Morpork.
Many of the novels in Pratchett's Discworld series parody real-world subjects such as film making, newspaper publishing, rock and roll music, religion, philosophy, Ancient Greece, Egyptian history, the Gulf War, Australia, university politics, trade unions, and the financial world. Pratchett also included further parody as a feature within the stories, including such subjects as Ingmar Bergman films, numerous fiction, science fiction, and fantasy characters, and various bureaucratic and ruling systems.
Pratchett wrote or collaborated on a number of Discworld books that are not novels in themselves but serve to accompany the series.
The Discworld Companion, written with Stephen Briggs, is an encyclopaedic guide to Discworld. The third edition was renamed The New Discworld Companion, and was published in 2003. The fourth and most recent edition of the companion, Turtle Recall was published on 18 October 2012. Briggs also collaborated with Pratchett on a series of fictional Discworld "mapps". The first, The Discworld Mapp (1995), illustrated by Stephen Player, comprises a large, comprehensive map of the Discworld itself with a small booklet that contains short biographies of the Disc's prominent explorers and their discoveries. Three further "mapps", have been released, focusing on particular regions of the Disc: Ankh-Morpork, Lancre, and Death's Domain.
Briggs and Pratchett also released several Discworld diaries and, with Tina Hannan, Nanny Ogg's Cookbook (1999). The design of this cookbook, illustrated by Paul Kidby, was based on the traditional Mrs Beeton's Book of Household Management, but with humorous recipes.
Collections of Discworld-related art have also been released in book form. The Pratchett Portfolio (1996) and The Art of Discworld (2004) are collections of paintings of major Discworld characters by Paul Kidby, with details added by Pratchett on the character's origins.
In 2005, Pratchett's first book for very young children was Where's My Cow? Illustrated by Melvyn Grant, this is a realisation of the short story Sam Vimes reads to his child in Thud!.
Pratchett resisted mapping the Discworld for quite some time, noting that a firmly designed map restricts narrative possibility (i.e., with a map, fans would complain if he placed a building on the wrong street, but without one, he could adjust the geography to fit the story).
Pratchett wrote four Science of Discworld books in collaboration with Professor of mathematics Ian Stewart and reproductive biologist Jack Cohen, both of the University of Warwick: The Science of Discworld (1999), The Science of Discworld II: The Globe (2002), The Science of Discworld III: Darwin's Watch (2005), and The Science of Discworld IV: Judgement Day (2013).
All four books have chapters that alternate between fiction and non-fiction: the fictional chapters are set within the Discworld universe, where characters observe, and experiment on, a universe with the same physics as ours. The non-fiction chapters (written by Stewart and Cohen) explain the science behind the fictional events.
In 1999, Pratchett appointed both Cohen and Stewart as "Honorary Wizards of the Unseen University" at the same ceremony at which the University of Warwick awarded him an honorary degree.
Pratchett collaborated with the folklorist Dr Jacqueline Simpson on The Folklore of Discworld (2008), a study of the relationship between many of the persons, places and events described in the Discworld books and their counterparts in myths, legends, fairy tales and folk customs on Earth.
Pratchett's first two adult novels, The Dark Side of the Sun (1976) and Strata (1981), were both science-fiction, the latter taking place partly on a disc-shaped world. Subsequent to these, Pratchett mostly concentrated on his Discworld series and novels for children, with two exceptions: Good Omens (1990), a collaboration with Neil Gaiman (which was nominated for both Locus and World Fantasy Awards in 1991), a humorous story about the Apocalypse set on Earth, and Nation (2008), a book for young adults.
After writing Good Omens, Pratchett began to work with Larry Niven on a book that would become Rainbow Mars; Niven eventually completed the book on his own, but states in the afterword that a number of Pratchett's ideas remained in the finished version.
Pratchett also collaborated with British science fiction author Stephen Baxter on a parallel earth series. The first novel, entitled The Long Earth was released on 21 June 2012. A second novel, The Long War, was released on 18 June 2013. The Long Mars was published in 2014. The fourth book in the series, The Long Utopia, was published in June 2015.
In 2012, the first volume of Pratchett's collected short fiction was published under the title A Blink of the Screen. In 2014, a similar collection was published of Pratchett's non-fiction, entitled A Slip of the Keyboard.
Pratchett's first children's novel was also his first published novel: The Carpet People in 1971, which Pratchett substantially rewrote and re-released in 1992. The next, Truckers (1988), was the first in The Nome Trilogy of novels for young readers, about small gnome-like creatures called "Nomes", and the trilogy continued in Diggers (1990) and Wings (1990). Subsequently, Pratchett wrote the Johnny Maxwell trilogy, about the adventures of a boy called Johnny Maxwell and his friends, comprising Only You Can Save Mankind (1992), Johnny and the Dead (1993) and Johnny and the Bomb (1996). Nation (2008) marked his return to the non-Discworld children's novel, and this was followed in 2012 by Dodger, a children's novel set in Victorian London. On 21 November 2013 Doubleday Children's released Pratchett's Jack Dodger's Guide to London.
In September 2014 an anthology of children's stories, Dragons at Crumbling Castle, written by Pratchett, and illustrated by Mark Beech, was published.