INTRODUCTION THE END IS NIGH It''s always the end of the world. Human cultures around the globe have been obsessed with this ultimate ending for thousands of years. Religious sects insist, as they have always done, that God is moments away from rolling up the scroll of the universe and exterminating us all. And secularists are no more optimistic: according to popular culture, an alien invasion is always poised to wipe out human civilisation, or our own technology has risen up to obliterate us in the form of armies of chromium robots or sinister computer programs. An asteroid with our name on it is hurtling towards us even as we speak. Scientists warn of impending climate catastrophe, and books and films flesh out those warnings with floods, famines and new global ice ages. Plagues and new diseases are queuing up to infect us all. I started writing this book before Covid-19 shut down societies across the globe, but I''m finishing it from inside that lockdown.

The pandemic has been an alarming and surreal experience for all of us, but I feel it has been slightly more on-the-nose for me, having watched my speculation about worldending plagues and collective disasters coming true all around me.* This book asks why we are so fascinated by the end of the world and starts from the fact that I myself have long been intrigued by it. As you might imagine, I''ve thought quite a lot about why that might be. Writing this book has crystallised these thoughts; I now wonder if my personal engagement with apocalypse might have something to do with my profession. I write science fiction. A writer necessarily takes a professional interest in the structure of storytelling, which is to * I hope, therefore, my next book will be about why we should give balding, middle-aged writers in Berkshire millions of pounds and our collective adulation. say: in beginnings, middles and ends. Knowing how a story ends tells us much about the way the story began and unfolded; it helps us to see what was important.

Apocalypse is not only the ultimate end but is also always bound up with beginnings and middles, in much the same - if somewhat more complex - way. And while some writers concentrate on individuals and the personal aspect of living and dying, science fiction writers tend to project out from the individual to interplanetary, even the galactic and universal. Perhaps this starts to explain why stories about the end of the world are so ubiquitous in popular culture. From the Apocalypse of St John to Dr. Strangelove, from H. G. Wells''s Time Machine to The Omega Man, from plagues of zombies and space viruses to the giant blue planet of Lars von Trier''s Melancholia crashing into Earth, what does it say about us? Why did the press go into hysterics in 2012 at the idea that the Mayan calendar, carved in Mesoamerican stone over 5,000 years ago, came to an end on 21 December of that year? Though this low-rent apocalyptic frenzy now looks foolish, at the time it generated much excitement as the date approached. Why? It is not, I think, because we are morbid, pessimistic or masochistic; on one level it''s perfectly sensible to be interested in the end of the world.

There are lots of beginnings in life, but to quote from the Matrix movie trilogy, ''Everything that has a beginning has an end.'' We are all mortal, and we will all die. One way of understanding our fascination with the end of the world is that such stories project our personal mortality onto the world. Just as we will each die, so the whole world will die at some point. There''s a Latin phrase for it: timor mortis, the fear of dying. We think about the end of the world - we speculate about it, write books and make films about it - as a way of thinking about the end of our individual lives. Unique among animals, it seems, we are aware of our mortality. As you read this sentence, you are drawing air into your lungs but you also know that one day you will draw your final breath.

It''s an alarming thing, but there''s no avoiding it. In the words of seventeenth-century poet and preacher John Donne, ''Death comes equally to us all, and makes us all equal when it comes.'' The twentieth-century writer and critic G. K. Chesterton expanded upon this point: There are two things in which all men are manifestly and unmistakably equal. They are not equally clever or equally muscular or equally fat, as the sages of the modern reaction (with piercing insight) perceive. But this is a spiritual certainty, that all men are tragic . No special and private sorrow can be so dreadful as the fact of having to die.

* Chesterton is discussing Walter Scott here - not a novelist whose reputation has particularly survived into the twentieth century, although a name you have surely heard; millions of passengers pass through Edinburgh Waverley Station every year, overlooked by the Scott monument and named after his first novel.+ What Chesterton loved about him was his grasp of ''the graver basis'' of our common humanity, ''the dark dignity of man'': ''Can you find no way?'' asks Sir Arthur Wardour of the beggar when they are cut off by the tide. ''I''ll give you a farm . I''ll make you rich.'' . ''Our riches will soon be equal,'' says the beggar, and looks out across the advancing sea. * G. K.

Chesterton, Dickens (1906), Chapter 10. + Similarly, the Edinburgh football club Heart of Midlothian FC (or simply ''Hearts'') is named after one of Scott''s best novels, The Heart of Midlothian (1818).