Science of Discworld III Read online

  CONTENTS

  COVER

  ALSO BY TERRY PRATCHETT, IAN STEWART & JACK COHEN

  TITLE PAGE

  EPIGRAPH

  CONCERNING ROUNDWORLD

  1. ANY OTHER BUSINESS

  2. PALEY’S WATCH

  3. THEOLOGY OF SPECIES

  4. PALEY ONTOLOGY

  5. THE WRONG TROUSERS OF TIME

  6. BORROWED TIME

  7. THE FISH IS OFF

  8. FORWARD TO THE PAST

  9. AVOIDING MADEIRA

  10. WATCH-22

  11. WIZARDS ON THE WARPATH

  12. THE WRONG BOOK

  13. INFINITY IS A BIT TRICKY

  14. ALEPH-UMPTYPLEX

  15. AUDITORS OF REALITY

  16. MANIFEST DESTINY

  17. GALÁPAGOS ENCOUNTER

  18. STEAM ENGINE TIME

  19. LIES TO DARWIN

  20. THE SECRETS OF LIFE

  21. NOUGAT SURPRISE

  22. FORGET THE FACTS

  23. THE GOD OF EVOLUTION

  24. A LACK OF SERGEANTS

  25. THE ENTANGLED BANK

  AFTERTHOUGHT

  INDEX

  COPYRIGHT

  BY THE SAME AUTHORS:

  TERRY PRATCHETT

  THE CARPET PEOPLE • THE DARK SIDE OF THE SUN • STRATA

  TRUCKERS • DIGGERS • WINGS • ONLY YOU CAN SAVE MANKIND

  JOHNNY AND THE DEAD • JOHNNY AND THE BOMB

  THE JOHNNY MAXWELL TRILOGY • JOHNNY AND THE DEAD (adapted by Stephen Briggs)

  THE UNADULTERATED CAT (with Gray Jolliffe) • GOOD OMENS (with Neil Gaiman)

  THE DISCWORLD ® SERIES:

  THE COLOUR OF MAGIC • THE LIGHT FANTASTIC • EQUAL RITES

  MORT • SOURCERY • WYRD SISTERS • PYRAMIDS • GUARDS! GUARDS!

  ERIC (with Josh Kirby) • MOVING PICTURES • REAPER MAN • WITCHES ABROAD

  SMALL GODS • LORDS AND LADIES • MEN AT ARMS • SOUL MUSIC

  INTERESTING TIMES • MASKERADE • FEET OF CLAY • HOGFATHER • JINGO

  THE LAST CONTINENT • CARPE JUGULUM • THE FIFTH ELEPHANT • THE TRUTH

  THIEF OF TIME • NIGHT WATCH • MONSTROUS REGIMENT • GOING POSTAL

  THE AMAZING MAURICE AND HIS EDUCATED RODENTS

  THE WEE FREE MEN • A HAT FULL OF SKY

  THE COLOUR OF MAGIC (graphic novel) • THE LIGHT FANTASTIC (graphic novel)

  MORT: A DISCWORLD BIG COMIC (illustrated by Graham Higgins)

  GUARDS! GUARDS! A DISCWORLD BIG COMIC (adapted by Stephen Briggs, illustrated by Graham Higgins)

  SOUL MUSIC: The illustrated screenplay • WYRD SISTERS: The illustrated screenplay

  MORT – THE PLAY (adapted by Stephen Briggs)

  WYRD SISTERS – THE PLAY (adapted by Stephen Briggs)

  GUARDS! GUARDS! – THE PLAY (adapted by Stephen Briggs)

  MEN AT ARMS – THE PLAY (adapted by Stephen Briggs)

  MASKERADE (adapted for the stage by Stephen Briggs)

  CARPE JUGULUM (adapted for the stage by Stephen Briggs)

  LORDS AND LADIES (adapted for the stage by Irana Brown)

  INTERESTING TIMES (adapted by Stephen Briggs)

  THE FIFTH ELEPHANT (adapted by Stephen Briggs)

  THE AMAZING MAURICE AND HIS EDUCATED RODENTS (adapted by Stephen Briggs)

  THE STREETS OF ANKH-MORPORK (with Stephen Briggs)

  THE DISCWORLD MAPP (with Stephen Briggs)

  A TOURIST GUIDE TO LANCRE a Discworld Mapp (with Stephen Briggs and Paul Kidby)

  DEATH’S DOMAIN (with Paul Kidby) • NANNY OGG’S COOKBOOK

  THE SCIENCE OF DISCWORLD (with Ian Stewart and Jack Cohen)

  THE SCIENCE OF DISCWORLD II: THE GLOBE (with Ian Stewart and Jack Cohen)

  THE DISCWORD COMPANION (with Stephen Briggs)

  THE PRATCHETT PORTFOLIO (with Paul Kidby) • THE LAST HERO (with Paul Kidby)

  IAN STEWART

  CONCEPTS OF MODERN MATHEMATICS • GAME, SET, AND MATH

  THE PROBLEMS OF MATHEMATICS • DOES GOD PLAY DICE?

  ANOTHER FINE MATH YOU’VE GOT ME INTO • FEARFUL SYMMETRY

  NATURE’S NUMBERS • FROM HERE TO INFINITY • THE MAGICAL MAZE

  LIFE’S OTHER SECRET • FLATTERLAND • WHAT SHAPE IS A SNOWFLAKE?

  THE ANNOTATED FLATLAND • MATH HYSTERIA

  JACK COHEN

  LIVING EMBRYOS • REPRODUCTION • PARENTS MAKING PARENTS

  SPERMS, ANTIBODIES AND INFERTILITY • THE PRIVILEGED APE

  STOP WORKING AND START THINKING (with Graham Medley)

  IAN STEWART AND JACK COHEN

  THE COLLAPSE OF CHAOS • FIGMENTS OF REALITY

  EVOLVING THE ALIEN (alternative title: WHAT DOES A MARTIAN LOOK LIKE?)

  WHEELERS (science fiction) • HEAVEN (science fiction)

  In crossing a heath, suppose I … found a watch upon the ground … The inference, we think, is inevitable; that the watch must have had a maker.

  WILLIAM PALEY

  NATURAL THEOLOGY

  Divine Design, the conscious process of creation, which Paley discovered, and which we now know is the explanation for the existence and purposeful form of all life, always has purpose in mind. If the Deity can be said to play the role of Watchmaker in nature, He is an all-seeing Watchmaker.

  THE REV. CHARLES DARWIN

  THEOLOGY OF SPECIES

  There is grandeur in this view of life … and that, whilst this planet has gone cycling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been, and are being, evolved.

  THE REV. RICHARD DAWKINS

  THE ORIGIN OF SPECIES

  There is grandeur in this view of life … and that, whilst this planet has gone cycling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been, and are being, evolved.

  CHARLES DARWIN

  THE ORIGIN OF SPECIES

  Natural selection, the blind, unconscious automatic process which Darwin discovered, and which we now know is the explanation for the existence and apparently purposeful form of all life, has no purpose in mind … If it can be said to play the role of watchmaker in nature, it is the blind watchmaker.

  RICHARD DAWKINS

  THE BLIND WATCHMAKER

  In crossing a heath, suppose I found a watch upon the ground. The inference, I think, is inevitable. Some careless chronometric surveyor must have dropped it.

  PRESERVED J. NIGHTINGALE

  WATCHES ABROAD

  CONCERNING ROUNDWORLD

  DISCWORLD IS REAL. It’s the way worlds should work. Admittedly, it is flat and goes through space on the backs of four elephants which stand on the shell of a giant turtle, but consider the alternatives.

  Consider, for example, a globular world, a mere crust upon an inferno of molten rock and iron. An accidental world, made of the wreckage of old stars, the home of life which, nevertheless, in a most unhomely fashion, is regularly scythed from its surface by ice, gas, inundation or falling rocks travelling at 20,000 miles an hour.

  Such an improbable world, and the entire cosmos that surrounds it, was in fact accidentally created by the wizards of Unseen University.1 It was the Dean of Unseen University who in fact destabilised the raw firmament by fiddling with it, possibly leading to the belief, if folk memory extends to sub-sub-sub-sub-atomic particle level, that it was indeed all done by somebody with a beard.

  Infinite in size on the inside, but about a foot across on the outside, the universe of Roundworld is now kept in a glass globe in UU, where it has been the source of much interest and concern.

  Mostly, it’s the source of concern. Alarmingly, it contains no narrativium.


  Narrativium is not an element in the accepted sense. It is an attribute of every other element, thus turning them into, in an occult sense, molecules. Iron contains not just iron, but also the story of iron, the history of iron, the part of iron that ensures that it will continue to be iron and has an iron-like job to do and is not, for example, cheese. Without narrativium, the cosmos has no story, no purpose, no destination.

  Nevertheless, under the ancient magical rule of As Above, So Below, the crippled universe of Roundworld strives at some level to create its own narrativium. Iron seeks out other iron. Things spin. In the absence of any gods to do the creating of life, life has managed, against the odds, to create itself. Yet the humans who have evolved on the planet believe in their hearts that there are such things as gods, magic, cosmic purpose and million-to-one chances that crop up nine times out of ten. They seek stories in the world which the world, regrettably, is not equipped to tell.

  The wizards, feeling somewhat guilty about this, have intervened several times in the history of Roundworld when it seemed to them to be on the wrong track. They encouraged fish (or fish-like creatures) to leave the seas, they visited the proto-civilisations of dinosaur-descendants and crabs, they despaired at the way ice and falling comets wiped out higher life forms so often – and they found some monkeys who were obsessed with sex and were quick learners, especially if sex was involved or could, by considerable ingenuity, be made to be involved.

  Again the wizards intervened, teaching them that fire was not for having sex with and in general encouraging them to get off the planet before the next big extinction.

  In this they have all been guided by Hex, UU’s magical thinking engine, which is immensely powerful in any case, and with Roundworld, which from Hex’s point of view is a mere sub-routine of Discworld and is practically godlike, although more patient.

  The wizards think they have sorted it all out. The monkeys have learned about their permanently threatened world via a type of technomancy called Science and may yet escape frozen doom.

  And yet …

  The thing about best laid plans is that they don’t often go wrong. They sometimes go wrong, but not often, because of having been, as aforesaid, the best laid. The kind of plans laid by wizards, who barge in, shout a lot, try to sort it all out by lunchtime and hope for the best, on the other hand … well, they go wrong almost instantly.

  There is a kind of narrativium on Roundworld, if you really look.

  On Discworld, the narrativium of a fish tells it that it is a fish, was a fish, and will continue to be a fish. On Roundworld, something inside a fish tells it that it is a fish, was a fish … and might eventually be something else …

  … perhaps.

  1 The greatest school of magic on the Discworld. But surely you know this?

  ONE

  ANY OTHER BUSINESS

  IT WAS RAINING. THIS WOULD, of course, be good for the worms.

  Through the trickles that coursed down the window Charles Darwin stared at the garden.

  Worms, thousands of them, out there under the soft rain, turning the detritus of winter into loam, building the soil. How … convenient.

  The ploughs of God, he thought, and winced. It was the harrows of God that plagued him now.

  Strange how the rustle of the rain sounds very much like people whispering …

  At which point, he became aware of the beetle. It was climbing up the inside of the window, a green and blue tropical jewel.

  There was another one, higher up, banging fruitlessly against the pane.

  One landed on his head.

  The air filled up with the rattle and slither of wings. Entranced, Darwin turned to look at the glowing cloud in the corner of the room. It was forming a shape …

  It is always useful for a university to have a Very Big Thing. It occupies the younger members, to the relief of their elders (especially if the VBT is based at some distance from the seat of learning itself) and it uses up a lot of money which would otherwise only lie around causing trouble or be spent by the sociology department or, probably, both. It also helps in pushing back boundaries, and it doesn’t much matter what boundaries these are, since as any researcher will tell you it’s the pushing that matters, not the boundary.

  It’s a good idea, too, if it’s a bigger VBT than anyone else’s and, in particular, since this was Unseen University, the greatest magical university in the world, if it’s a bigger one than the one those bastards are building at Braseneck College.

  ‘In fact,’ said Ponder Stibbons, Head of Inadvisably Applied Magic, ‘theirs is really only a QBT, or Quite Big Thing. Actually, they’ve had so many problems with it, it’s probably only a BT!’

  The senior wizards nodded happily.

  ‘And ours is certainly bigger, is it?’ said the Senior Wrangler.

  ‘Oh, yes,’ said Stibbons. ‘Based on what I can determine from chatting to the people at Braseneck, ours will be capable of pushing boundaries twice as big up to three times as far.’

  ‘I hope you haven’t told them that,’ said the Lecturer in Recent Runes. ‘We don’t want them building a … a … an EBT!’

  ‘A what, sir?’ said Ponder politely, his tone saying, ‘I know about this sort of special thing and I’d rather you did not pretend that you do too.’

  ‘Um … an Even Bigger Thing?’ said Runes, aware that he was edging into unknown territory.

  ‘No, sir,’ said Ponder, kindly. ‘The next one up would be a Great Big Thing, sir. It’s been postulated that if we could ever build a GBT, we would know the mind of the Creator.’

  The wizards fell silent. For a moment, a fly buzzed against the high, stone-mullioned window, with its stained-glass image of Archchancellor Sloman Discovering the Special Theory of Slood, and then, after depositing a small flyspeck on Archchancellor Sloman’s nose, exited with precision though a tiny hole in one pane which had been caused two centuries ago when a stone had been thrown up by a passing cart. Originally the hole had stayed there because no one could be bothered to have it fixed, but now it stayed there because it was traditional.

  The fly had been born in Unseen University and because of the high, permanent magical field, was far more intelligent that the average fly. Strangely, the field never had this effect on wizards, perhaps because most of them were more intelligent than flies in any case.

  ‘I don’t think we want to do that, do we?’ said Ridcully.

  ‘It might be considered impolite,’ agreed the Chair of Indefinite Studies.

  ‘Exactly how big would a Great Big Thing be?’ said the Senior Wrangler.

  ‘The same size as the universe, sir,’ said Ponder. ‘Every particle of the universe would be modelled within it, in fact.’

  ‘Quite big, then …’

  ‘Yes, sir.’

  ‘And quite hard to find room for, I should imagine.’

  ‘Undoubtedly, sir,’ said Ponder, who had long ago given up trying to explain Big Magic to the rest of the senior faculty.

  ‘Very well, then,’ said Archchancellor Ridcully. ‘Thank you for your report, Mister Stibbons.’ He sniffed. ‘Sounds fascinatin’. And the next item: Any Other Business.’ He glared around the table. ‘And since there is no other busi—’

  ‘Er …’

  This was a bad word at this point. Ridcully did not like committee business. He certainly did not like any other business.

  ‘Well, Rincewind?’ he said, glaring down the length of the table.

  ‘Um …’ said Rincewind. ‘I think that’s Professor Rincewind, sir?’

  ‘Very well, professor,’ said Ridcully. ‘Come on, it’s past time for Early Tea.’

  ‘The world’s gone wrong, Archchancellor.’

  As one wizard, everyone looked out at what could be seen of the world through Archchancellor Sloman Discovering the Special Theory of Slood.

  ‘Don’t be a fool, man,’ said Ridcully. ‘The sun’s shining! It’s a nice day!’

  ‘Not this world, sir,’ said Rincewind.
‘The other one.’

  ‘What other one?’ said the Archchancellor, and then his expression changed.

  ‘Not—’ he began.

  ‘Yes, sir,’ said Rincewind. ‘That one. It’s gone wrong. Again.’

  Every organisation needs someone to do those jobs it doesn’t want to do or secretly thinks don’t need doing. Rincewind had nineteen of them now, including Health and Safety Officer.1

  It was as Egregious Professor of Cruel and Unusual Geography that he was responsible for the Globe. These days, it was on his desk out in the gloomy cellar passage where he worked, work largely consisting of waiting until people gave him some cruel and unusual geography to profess.

  ‘First question,’ said Ridcully, as the faculty swept along the dank flagstones. ‘Why are you working out here? What’s wrong with your office?’

  ‘It’s too hot in my office, sir,’ said Rincewind.

  ‘You used to complain it was too cold!’

  ‘Yes, sir. In the winter it is. Ice freezes on the walls, sir.’

  ‘We give you plenty of coal, don’t we?’

  ‘Ample, sir. One bucket per day per post held, as per tradition. That’s the trouble, really. I can’t get the porters to understand. They won’t give me less coal, only no coal at all. So the only way to be sure of staying warm in the winter is to keep the fire going all summer, which means it’s so hot in there that I can’t work in – don’t open the door, sir!’

  Ridcully, who’d just opened the office door, slammed it again, and wiped his face with a handkerchief.

  ‘Snug,’ he said, blinking the sweat out of his eyes. Then he turned to the little globe on the desk behind him.