The Science of Discworld IV Judgement Da - By Terry Pratchett, Ian Stewart Page 0,75

beasts has acquired language, imagination, and a penchant for stories: a special, wholly new thing in the cosmos. Narrativium has escaped from Discworld into Roundworld; now some things do happen because there is a creature that wants them to.

Perhaps there are many such creatures, all over the place; perhaps as many as one species per hundred million stars. But we should be very careful indeed, just in case we’re the only one.

Just one story in the whole cosmos.

Everywhere else, only laws.

fn1 A little too promptly for some scientists, who complained that the results were announced before being peer-reviewed for journal publication.

fn2 Although often thought to be a myth, this story has some basis. Newton often said that he had been inspired by the fall of an apple. Wikipedia states: ‘Acquaintances … such as William Stukeley, whose manuscript … has been made available by the Royal Society, confirm the incident, though not the cartoon version that the apple actually hit Newton’s head.’

fn3 For a dominant frequency ω, the combination sin(ωt) + 0.75 sin(3ωt) + 0.5 sin(5ωt) + 0.14 sin(7ωt) + 0.5 sin(9ωt) + 0.12 sin(11ωt) + 0.17 sin(13ωt), going as far as the 13th harmonic, is pretty convincing to the human ear.

fn4 In the science fiction novel Light by M. John Harrison, aliens living around the Galactic Core have invented six different space drives, each based on a different theory of fundamental physics, several of which are known to be wrong. All of the drives work fine. In Roundworld, our theories of aerodynamics are approximations that ignore atomic-scale structure, yet aircraft fly perfectly well. Lies-to-children often work.

THIRTEEN

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RINCEWIND’S ADVENTURES IN ROUNDWORLD

The arrival into Roundworld was always a hit-or-miss business these days, Rincewind knew. The people in the Inadvisably Applied Magic group had a word for it – or, more accurately, a number of equations, which you would see on the walls, being drawn and then subsequently redrawn by the next researcher, or survivor. But the Dean said that he knew what he was doing, and landed them in the middle of London; regrettably during a race, which Rincewind inadvertently won; and he had to submit to multiple slaps on the back, admiration for his wizard’s outfit, and many thanks from the organisers for helping the Orangutan Foundation to raise so much money.

He was surprised, as well, when someone he had thought was the Librarian turned out to be a young woman in an outfit, which led to hilarious misunderstanding as a result of which both he and the Dean had to run a little further.

They found a pleasant park with trees, and ducks in the pond, and considered their circumstances. After a while Rincewind said, ‘I told you about the automobiles, didn’t I? Terrible waste of resources. Honestly, is this really Homo sapiens? Horses breed other horses, eat grass and you get fertiliser as well; don’t you remember the street cries of “Tuppence a bucket, well stamped down”?’

‘Yes,’ said the Dean. ‘I also remember “gardyloo”, and it wasn’t very pleasant. I must admit, though, that they have progressed in this era – but I think at enormous cost, which most of them don’t recognise, although right now I see people in very decent health: lots of colour, no heads on railings … all in all, if you don’t think too hard … though we know what’s coming their way.’ Then the Dean pointed to a building in the distance and said, ‘Fairly big place there; I’m sure I’ve seen it before.’

‘You have,’ said Rincewind. ‘You remember the Great Fire of London? We helped Mister Pepys to bury his Parmesan cheese.’

‘Oh, right. I wonder if the fellow got it back again?’

‘No,’ said Rincewind. ‘I asked him where he put it, and I couldn’t remember either, so I went back to the moment when he buried it and doubled up myself; if you remember, Mrs Whitlow was very happy to see it. I figured that since he was going to forget the cheese anyway … well, it would be such a wicked shame to let it go to waste.’

‘It was a bad move,’ said the Dean. ‘Causality, you see.’

‘Don’t talk to me about causality,’ said Rincewind. ‘It hasn’t done me that many favours, what with one thing and another. But since we are here and chatting, I have to ask: well, what did you do to make this place? I mean, you say you just put your hand in some firmament and, if I may quote, you “wiggled it about”. I must