The Science of Discworld III - Darwin's Watch tsod-3

by Terry Pratchett

  `Now, chaps,' he said. `This should not be hard, as the Archchancellor has said. If at all possible don't talk to anyone and don't touch anything. In and out, that's the ticket. I want this done fast. I have a ... theory about that. So don't waste time, wherever you go. Are we all ready? Very well ... Aardvarker, Professor A ... '

  One by one, with confidence or trepidation or a mixture of both, wizards stepped into Hex's circle of light and vanished. As they did so, little pointy-hatted wizard symbols appeared at points in the tangle of lights above.

  Rincewind watched gloomily, and didn't join in the ragged cheer as, one by one, red circles began to wink out.

  Ponder had taken him aside earlier and had explained that, since Rincewind was so experienced at this sort of thing, he was going to be given four of the most, er, interesting tasks. That was how he had put it: 'er, interesting'. Rincewind knew all about 'er, interesting'. There was a giant squid out there with his name on it, that's what it meant.

  A movement at the end on the hall made him look around. It was a chest, a metal-bound box of the kind favoured by people who bury treasure, and it walked on hundreds of little pink legs. He groaned. He'd left it asleep on the wardrobe in his bedroom, with its feet in the air.

  'Hmm?' he said.

  `Rincewind! Off you go, best of luck!' Ponder repeated. `Hurry up!' There was nothing for it. Rincewind walked into the circle, and fell over as the ship moved gently under him.

  It was dawn, and a clammy sea mist was drifting across the deck. Rigging creaked, the water lapped far below. There was no other sound. The air smelled warm and exotic.

  There was a small cannon only a few feet away. Rincewind knew about them. He was the only wizard to have seen one, over in the Agatean Empire, where they were known as `Barking Dogs'. He was sure that one of the rules associated with them was `do not stand in front'.

  Slowly, he reached inside his shirt and pulled out his pointy hat. It was red, or rather, it was the colour that red becomes after being washed, eaten, retrieved, scorched, buried, crushed, engulfed, washed again and wrung out far, far too often.

  No wearing of pointy hats? Were they mad? He pulled at it a bit to get it back to its comfortable shapeless shape, and put it on. That felt much better. A pointy hat meant you weren't just anyone.

  He unrolled his instructions.

  1. Remove ball from `cannon'

  There was no one around. There was a stack of metal balls by the cannon. Rincewind pulled the barrel around with some effort, felt down the hole, and grunted as his fingers touched the top of another ball at the far end.

  How could he get it out? The way to get a ball out of a Barking Dog was to set a match to its tail, but Ponder had said this wasn't an option. He cast around, and saw a bundle of tools by the stack; one was a rod with an end like a super-corkscrew.

  Carefully, he pushed it down the cannon, wincing at every clink. Twice he felt the curved springy bits engage with the ball, and twice it came away and rolled back with a thud.

  At the third attempt he was able to get the tapped ball almost out of the mouth of the barrel, and slid his fingers under it.

  Well, that wasn't too hard, was it? He dropped it over the side, where the sea swallowed it with a 'plomp!'

  This caused no stir anywhere. Job done, and nothing horrible had happened at all! He pulled a scrap of paper out of his pocket. It was important to get the words right.

  `Return-' he began, and stopped. With a little metallic grinding noise, another ball rolled gently off the pile, across the deck, and leapt into the cannon's mouth.

  `O-kay,' said Rincewind slowly. Of course. Obviously. Why had he thought otherwise for even one second?

  Sighing, he picked up the ball grasper, rammed it down the barrel, caught the ball, and jerked it out so hard that it would have made a giveaway noise hitting the deck. Fortunately, it landed on Rincewind's foot.

  A little metallic sound disturbed him while he was lying across the barrel making the traditional 'gheeee' noise of those who are screaming through clenched teeth.

  It was the noise of another cannon ball rolling across the deck. He jumped on it, picked it up, and felt a slight resistance trying to tug it out of his hands. He wrenched against the invisible force, spun around and the ball flew out of his hands and over the rail.

  This time the 'plomp!' caused an interrogatory mumble from below decks.

  The last remaining ball started to roll towards the cannon.

  `Oh no you don't!' snarled Rincewind, and grabbed it. Again the force tried to pull the ball away from him, but he clung on tightly.

  There was the sound of footsteps climbing stairs. Somewhere close, in the fog, someone sounded angry.

  Then in the billows in front of Rincewind there was ... something. He couldn't make out the shape, but it disturbed the fog, making an outline of sorts. It looked like It let go as someone hurried closer. Rincewind growled in triumph, staggered backwards, tipped over the rail and, still clutching the cannon ball, went `plomp!'

  `Look at the red circles, sir!' shouted Ponder.

  Erratically, in the drifting tangle of lights, the red circles were winking out. The yellow line was extending.

  `That's the style, Mr Stibbons!' the Archchancellor roared. `Keep pounding away!'

  Wizards were scuttling through the hall, getting fresh instructions, catching their breath and disappearing in the circle again.

  Ridcully nodded at the stretcher containing the screaming Pennysmart, as it was hurried away to the Infirmary.

  `Never seen that shade of purple on a leg,' he said. `I told him to look where he was going. You heard me, didn't you?'

  `He says he was dropped right on top of the fish,' said Ponder. `I'm afraid Hex is running at the very limit of his power, sir. We're bending an entire timeline. You've got to expect some accidents. A few of the returning wizards are reappearing in the fountain. We just have to accept that it's better than them reappearing inside walls.'

  Ridcully surveyed the throng, and said: `Here comes one from the fountain, by the look of it ... '

  Rincewind limped in, his face like thunder, water still streaming off him, with something grasped in his hands. Halfway across the hall a fish fell out of his robe, in obedience to the unbreakable laws of humour.

  He reached Ponder, and dropped the cannon ball on the floor.

  `Do you know how hard it is to shout underwater?' he demanded.

  `But I see you were successful, Rincewind,' said Ridcully.

  Rincewind looked up. All over the streaming lines, little pointy wizard symbols were appearing and disappearing.

  `No one told me it would fight back! It fought back! The cannon tried to load itself.'

  'Aha!' said Ridcully. `The enemy is revealed! We're nearly there! If they are breaking the-'

  'It was an Auditor,' said Rincewind, flatly. `It was trying to be invisible but I saw it outlined in the fog.'

  Ridcully sagged a little. A certain exuberance faded from his face. He said, `Oh, darn,' because an amusing misunderstanding in his youth had led him to believe that this was the worst possible word you could say.

  `We've found no evidence of them,' said Ponder Stibbons.

  `Here? Did we look? We wouldn't find any anyway, would we?'

  said Ridcully. `They'd show up as natural forces.'

  `But how could they exist here? All those things work by themselves here!'

  `Same way we did?' said Rincewind. `And they'll meddle with anything. You know them. And they really, really hate people ...'

  Auditors: personifications of things that have no personality that can be imagined. Wind and rain are animate, and thus have gods. But the personification of gravity, for example, is an Auditor or, rather Auditors. In universes that run on narrativium rather than automatic, they are the means by which the most basic things happen.

  Auditors are not only unimaginative, they find it impossible to imagine what imagination is.

  They are never found in groups of
less than three, at least for long. In ones and twos they quickly develop personality traits that make them different, which to them is fatal. For an Auditor to have an opinion that differs from that of its colleagues is certain ... cessation. But while individual Auditors cannot hold an opinion (because that would make them individual), Auditors as a whole certainly can, and with grim certainty they hold that the multiverse would be a lot better off with no life in it. Life gets in the way, tends to be messy, acts unpredictably and reverses entropy.

  Life, they believe, is an unwanted by-product. The multiverse would be more reliable if there wasn't any. Unfortunately, there are rules. Gravity is not allowed to increase a millionfold and laminate all local life forms to the bedrock, highly desirable though that would appear to be. Simply mugging life forms merely walking, flying, swimming or oozing past would attract attention from higher authority, which Auditors dread.

  They are weak, not very clever and always afraid. But they can be subtle. And the wonderful thing about intelligent life, they have discovered, is that with some care it can be persuaded to destroy itself.

  16. MANIFEST DESTINY

  THE WIZARDS ARE DISCOVERING THAT changing history is not so easy, even when you've got a time machine. The Auditors aren't helping, but history has its own metaphorical Auditor, often called `historical inertia'.

  Inertia is the innate tendency of moving objects to continue moving along much the same track, even if you try to divert them; it is a consequence of Newton's laws of motion. Historical inertia has a similar effect but a different cause: changing a single historical event, however important it may appear, may have no significant effect on the social context that directs the path of history.

  Imagine we've got a time machine, and go back to the past. Not too far, just to the assassination of Abraham Lincoln. In our history, the President lived till the following morning, so a tiny deflection of the assassin's bullet could make all the difference. So we arrange a small deflection, and he is hit but recovers, with no noticeable brain damage. He cuts a couple of appointments while he recuperates, and then he goes on to do ... what?

  We don't know anything about that new version of history.

  Or do we? Of course we do. He doesn't turn into a hippopotamus, for a start, or a Ford Model T Or disappear. He goes on being President Abraham Lincoln, hedged in by all the political expediencies and impossibilities that existed in our version of history and still exist in his.

  The counterfactual[44] scenario of a live Lincoln raises many questions. How much do you think being the American President is like driving a car, going where you want to? Or sitting in a train, observing the terrain that others drive you through?

  Somewhere in between, no doubt.

  Ordinarily, we don't have to think much about counterfactuals, precisely because they are contrary to fact. But mathematicians think about them all the time -'if what I think happens is wrong, what can I deduce that might prove it wrong?' Any consideration of phase spaces automatically gets tangled up in worlds of if. You don't really understand history unless you can take a stab at what might have happened if some major historical event had not occurred. That's a good way to appreciate the significance of that event, for a start.

  In that spirit, let's think about that altered `now': the beginning of the West's third millennium of history, but without Lincoln having been assassinated in its past. What would your morning newspaper be called? Would it be different? Would you still be having much the same breakfast ritual, bacon and eggs and a sausage perhaps? What about the World Wars? Hiroshima?

  A very large number of stories have been written with this kind of theme: Wilson Tucker's The Lincoln Hunters is set in such an 'alternat(iv)e universe' and tackles the Lincoln question.

  Curious things happen in our minds when they are presented with any fictional world. Consider for a moment the London of the late nineteenth century. It did have Jack the Ripper, and we can wonder about the real-world puzzle of who he was. It had Darwin, Huxley and Wallace, too. But it did not have Sherlock Holmes, Dracula, Nicholas Nickleby, or Mr Polly. Nevertheless, some of the best portrayals of the Victorian world are centred around those characters. Sometimes the fictional portrayals are intended to paint a humorous gloss on the society of the period. The Flintstones put just such a gloss on human prehistory, so much so that in order to think rationally about our evolution we must excise all those images, which is probably an impossible task.

  Sherlock Holmes and Mr Polly were Victorians in just the same sense that the tyrannosaur and triceratops in Jurassic Park were dinosaurs. When we envisage Triceratops, we cannot avoid the memory of that warty purple-spotted Jurassic Park skin, as the beast lies on its side, breathing stertorously. And Tyrannosaur, in our mind's eye, is running after the jeep, bobbing its head like a bird. When we envisage late nineteenth-century Baker Street it's very difficult not to see Holmes and Watson (probably in one of their filmic versions) hailing a four-wheeler, off to solve another crime. Our pictures of the past are a mixture of real historical figures and scenarios peopled by fictional entities, and it's difficult to keep them apart, especially as films and TV series acquire better technologies to latch into those spurious pictures in our heads.

  The 1930s philosopher George Herbert Mead made much of the rather obvious point that the present, in a causal world, does not only determine (`constrain' if you prefer) the future, it also affects the past, in just this sense: if I discover a new fact about the present, then the (conceptual) past that led up to the new present must also have been different. Mead thereby enabled a rather cute way of seeing how good the portrayals of Sherlock Holmes, or of the Jurassic Park tyrannosaur, are. If my picture of the present isn't altered at all by the presence or absence of Sherlock Holmes in the 1880s, or if my construction of the present by evolutionary processes isn't altered at all by seeing Jurassic Park, then these are consistent inventions.

  Dracula and the Flintstones are inconsistent inventions: if they really existed in our past; then the present isn't what we think it is. Much of the fun of `worlds of if' stories, and of many consistent fictions like The Three Musketeers, is that they show closed-loop causalities in our apparent past. Whether or not D'Artagnan had aggregated the Musketeers and thereby brought into being much of the causal history of seventeenth-century France, children of later centuries would learn the same history in the textbooks. Ultimately, consistent historical fictions make no difference.

  In The Science of Discworld II we played with this idea in several ways: the, presence of the Elves was, surprisingly, consistent with our history; stopping them led to stagnation of humans and had to be reversed. In this book the meddling of the Unseen University wizards, in Victorian history this time, is trying to create an apparently internally caused history in which Darwin wrote The Origin of Species and not Theology of Species. We are going to use this trick to illuminate the causalities of human history.

  In order to do this convincingly, we must make the Discworld intrusions consistent, but even then we must address the convergence/ divergence problem, which is this. Would such a meddled-with world converge on to ours, demonstrating that history is stable, or would any tiny difference start a divergence that became wider and wider, proving history to be unstable?

  Most people think the latter. Indeed, even the wildly imaginative physicists who believe that a new world history is created by each and every decision in this universe, spawning new universes in which the other choices were implemented, don't imagine that the histories converge. No, each universe goes its own way, spitting out new and divergent universes as it goes. The Trousers of Time are a tree: their legs can branch but never merge.

  The Worlds of If stories were divided on this issue. Some had each tiny change in the past getting amplified, resulting in vast changes now: we've mentioned Bradbury's story where you trod on a butterfly in the far past, on a dinosaur hunt, and came back to find a fascist regime. Or the changes you made were all wiped out, because there was a g
igantic all-powerful inertia-of-events Kismet that you couldn't change. However you tried to avoid your fate, that only made it more certain to happen. And some stories took a middle way; some things converged and others didn't.

  This, we think, is the rational way to think about time travel and altering the past.

  After all, we don't change the rules by which the past works. Gravity still operates, sodium chloride crystals are still cubical, people fall in and out of love, misers hoard and spendthrifts squander. What we change is what physicists call the `initial conditions'. We change the positions of a few of the pieces on the Great Chessboard of Life, The Universe and Everything, but we still keep to the rules of chess. That's how the wizards operated in The Science of Discworld II. They went back in time to remove the Elves from the game board; then they went back again to stop themselves making that mistake.

  We are now ready to think about our question above: would the names of newspapers have changed if Abraham Lincoln had lived to a ripe old age?

  Perhaps some of them would, because some cultures would have become rather different. Perhaps Quebec wouldn't have been French; perhaps New York would have been Dutch. But names like Daily Mail, Daily News and New York Times are so obvious, so appropriate, that even if the Roman Empire were still running things, the Latin equivalents would seem fitting. Someone would have invented flush toilets, and there would have been a steam engine time, when several people invented steam power. Some things in Western culture seem so likely, from toilet paper on up to (as soon as paper is invented) daily newspapers to plastics to artificial wood ... Technology seems to have a set of rules for its advancement, so that it seems rational to expect gramophones of some kind if people make music with musical instruments, then tape players when people get used to electricity and its possibilities for amplifi cation. Then from analogue to digital, to computers ... some things seem inevitable.