The day Terry Pratchett died, in 2015, my nine-year-old made a model of a bearded man in a big hat holding hands with Death. Few people have written as much about death as Pratchett. No one else has written about death in a way that would make a nine-year-old want to play with him. The Death who stalks Pratchett’s Discworld is a lonely, bewildered figure, unable to understand why he’s possibly not the ideal person to adopt a little girl, or why people are unsettled by the idea of him dressing up as Santa. But Death always gets you in the end. He got Pratchett through the back of his cerebral cortex and shrank his brain, something he referred to as “an embuggerance”.
Caring for someone who has dementia is an overwhelmingly vivid experience, full of pain and comedy. There are heartbreaking and funny stories in A Life With Footnotes – started by Pratchett himself but written and completed by his longtime assistant Rob Wilkins – about the things that Pratchett’s shrinking brain made him do. He once accidentally donated £50,000 to Bath Postal Museum, for instance. Moments like that can supplant your memories of what a person was like before; here, Wilkins, who started working for the author in 2000, attempts to recover Pratchett pre-dementia. His closeness to the subject means that the book is sometimes joyfully, sometimes painfully, intimate. The description of the day Pratchett’s daughter, Rhianna, was born, for example, is so animated by love, it’s as if this treasured moment was a jewel that Pratchett placed in Wilkins’s care, to ensure it would not be stolen away by the embuggerance.
The book follows the shape of Wilkins’s relationship with Pratchett. After hearing Jilly Cooper talk about her invaluable PA, Pratchett was filled with staff envy and hired Wilkins as an assistant. Over the years, the role grew into that of amanuensis and “keeper of the anecdotes”. The first half of this book is Wilkins curating these stories. Such as the time that, while working as press officer at the Central Electricity Generating Board, Pratchett had to deal with the story of a worker who took home a radioactive paintbrush from a nuclear facility and used it to touch up the paintwork in his house; an incident that led to a kind of pebble-dash apocalypse. When he worked on the Bucks Free Press, the editor would not cover the moon landings as they were of no local interest, until someone pointed out that “the moon shines on High Wycombe, too”.
As Pratchett needed more and more assistance, his personal assistant became more important to him. To start with, his job was “tidying up” pages covered in clashing layouts and fonts (Pratchett was very font-fickle). Later, the author took to dictating to him. Towards the end, Wilkins had to hold Pratchett’s hand and guide him through his last explorations of the Discworld. Outside family, Wilkins probably knew Pratchett better than anyone else and it is wonderful to have this closeup picture of the writer’s working life, with its arguments and doubts, naps and negotiations. This is not a hagiography. The Pratchett who emerges can be curmudgeonly, vain, and infuriated and puzzled by the way the world has underestimated him.
Why is he so underestimated? The world he created was brilliantly absurd – elephants all the way down – and strangely convincing. I remember arriving by car in Palermo, in Sicily, one day and one of my children saying “we’re on holiday in Ankh-Morpork”. Unlike any other fantasy world, Discworld constantly responds to our own. You’ve only got to look at the titles of the books (Reaper Man, The Fifth Elephant) – parodies of films. Discworld is the laboratory where Pratchett carried out thought experiments on everything from social class and transport policy to the nature of time and death.
He is often compared with PG Wodehouse but he’s closer to Swift. Or to GK Chesterton, from whom he drew so much inspiration. Like Chesterton, he is too bursting with ideas to confine himself to neat, prize-worthy volumes. He couldn’t even slow down enough to divide the books into chapters. And he has that Chestertonian quality of merriment, of intellectual play. Discworld, like Middle-earth, is immersive in a way that tempts people to dress up, draw street maps, tabulate its rules and pretend they live there. Even Pratchett himself, with his rings and his sword and his “manorette” of a house, sometimes gave the impression that he had just come down from the Ramtops.
Pratchett left instructions that, on his death, the hard drive from his computer be removed and run over by a specific steam engine – the Lord Jericho – at the Great Dorset Steam Fair. Wilkins is in a position to let us know some of what was lost there. An unused title – The Lost Incontinent. A police procedural called The Feeney. A sequel to The Amazing Maurice. And Cab’s Well – the story of the creature who lives at the bottom of a well and whose job it is to make wishes come true. I got a bit emotional reading that because, as the writer and TV producer John Lloyd said at his funeral: “Of all the dead authors in the world, Terry Pratchett is the most alive.”
Writing is an isolating job – “a life of homework”, according to my next-door neighbour. One surprising thing to emerge from this biography is just how much Pratchett valued and acknowledged the help of a circle of family, friends and fans. Wilkins is pre-eminent here but there’s a roster of advisers, illustrators, toymakers, cartographers and fellow writers – notably Neil Gaiman – who are accorded places of honour in the Venerable Order of the Honeybee. The Pratchett who emerges from this book is good at many things – beekeeping, mead making, gardening, negotiating, pissing people off – but most of all, he seems to have been good at love. Gaiman said: “This is the loophole writers get – as long as you read us, we’re not dead.” Keep on reading him.
• Terry Pratchett: A Life With Footnotes by Rob Wilkins is published by Doubleday (£25). To support the Guardian and Observer order your copy at guardianbookshop.com. Delivery charges may apply