Science of Discworld III

be too busy runnin’ around like a monkey in a banana plantation to spot the clues, eh?’
    ‘It would be true to say that his full theory of natural selection was evolved on mature reflection some time after his voyage, yes,’ said Ponder, carefully answering a slightly different question.
    ‘And this chap Lawson was important?’
    ‘Hex believes so, sir. In a way, everyone Darwin met was important. And everything he saw.’
    ‘And then whoosh, this chap was hit by a rock? I call that suspicious.’
    ‘Hex does too, sir.’
    ‘I’ll be jolly glad when we’ve got this Darwin to the damn islands, then,’ said the Archchancellor. ‘We’ll need a holiday after this. Oh well, I’ll address the wizards now. I hope we’ll have enough for—’
    ‘Er, we haven’t just got to get him to the islands. We’ve got to get him all the way home, sir,’ said Ponder. ‘He’ll be away from home for nearly five years.’
    ‘Five years?’ said the Dean. ‘I thought visiting the wretched islands was what it was all about!’
    ‘Yes and then again, in a very real sense, no, Dean,’ said Ponder. ‘It would be more correct to say they later became what it was all about. He was actually there for a little more than a month. It was a very long voyage, sir. They went all around the world. I’m sorry, I hadn’t made that clear. Hex, show the entire timelines, please.’
    The display began to recede, drawing from nowhere more and more tangles and loops, as if half a dozen cosmic kittens had been given stars to play with instead of balls of wool. There was a gasp from the throng of wizards.
    The tangles were still streaming away overhead when the Dean said: “There’s millions of the wretched things!’
    ‘No, Dean,’ said Ponder. ‘It looks like that, but there are only 21,309 important nodalities at this point. Hex can deal with almost all of them. They involve quite minute changes at the quantum level.’
    The wizards continued to stare upwards as the whorls and loops flashed by and dwindled.
    ‘Someone really doesn’t want that book,’ said the Lecturer in Recent Runes, his face illuminated by the multi coloured glow.
    ‘In theory there isn’t a someone in charge,’ said Ponder.
    ‘But the odds against Darwin writing Origin are getting bigger by the minute!’
    ‘The odds against anything actually happening are huge, when you come to think about it,’ said Ridcully. ‘Take poker, for example. The odds against four aces are huge, but the odds of having any four cards at all are really big.’
    ‘Well put, Archchancellor!’ said Ponder. ‘But this is a crooked game.’
    Ridcully strode out into the centre of the Great Hall, his face illuminated by the glowing map.
    ‘Gentlemen!’ he bellowed. ‘Some of you already know what this is about, eh? We’re going to force a history on Roundworld! It’s one that should be there already! Something is trying to kill it, gentlemen. So if someone wants to stop it happening, we want to make it happen all the more! You will be sent into Roundworld with a series of tasks to do! Most of them have been made very simple so that wizards can understand them! Shortly our missions for tomorrow, should you chose to accept them, will be given to you by Mr Stibbons. If you do not choose to accept them, you are free to choose dismissal! We’re starting at dawn! Dinner, Second Dinner, Midnight Snack, Somnambulistic Nibbles and Early Breakfast will be served in the Old Refectory! There will be no Second Breakfast!’
    Over a chorus of protest he went on: ‘We are taking this seriously , gentlemen!’

TWELVE
THE WRONG BOOK
    O UR FICTIONAL D ARWIN HAS A lot more in common with the ‘real’ one – the Darwin of the particular timeline that you inhabit, the one who wrote The Origin and not The Ology – than might at first be apparent. Or plausible. The irresistible force of narrativium induces us to imagine Charles Darwin as an old man with a beard, a stick, and a faint but definite hint of gorilla. And so he was, in his old age. But as a young man he was vigorous, athletic, and engaged in the kind of exuberant and not always politically correct activities that we expect of young men.
    We’ve already learned of the real Darwin’s amazing fortune in getting on board the Beagle and remaining there, culminating in his boundless delight at the geology of the coral island of St Jago. But there are other crucial nodalities, points of intervention, and thaumic occlusions in