The Science of Discworld II

complete with a built-in packet of fertiliser. A bean-counting tomato could reduce its level of suitability and still ensure that its seeds, rather than those of the competition, were propagated (the juiciest tomatoes used to be from the plants growing at the sewage farm …). But an over-committed banana avoids the need to test such fine points. By going over the top, losing its seed-producing capacity entirely and relying on humans to propagate it, it ensures that it wins so comfortably that no competitor even gets a look in.
    4 … which can be applied so overpoweringly that the people who aren’t Us aren’t anything. See the Imperial China parody – the Agatean Empire – in Interesting Times , and a number of Roundworld cultures, too. Being Them is quite a step up by comparison.

TWENTY-ONE
THE NEW SCIENTIST
    T HERE WAS SOMETHING CALLED , as far as Ponder could work out, psyence. All his expertise as a reader of invisible writings was needed to get a grip on this idea – L-space was very hazy about the future of this world.
    â€˜As far as I can tell,’ he reported, ‘it’s a way of making up stories that work. It’s a way of finding things out and thinking about them … psy -ence, you see? “Psy” means “mind” and “ence” means, er, esness . It works on Roundworld in the way magic does at home.’
    â€˜Useful stuff, then,’ said Ridcully. ‘Anyone doing it?’
    â€˜Hex is going to try to take us to what appear to be practical examples of it,’ said Ponder.
    â€˜Time travel again ?’ said the Dean.
    The white circle appeared on the floor …
    â€¦ and on the sand, and vanished.
    The wizards looked around.
    â€˜All right, then,’ said Ponder. ‘So … dry climate, evidence of agriculture, fields of crops, irrigation ditches, naked man turning a handle, man staring at us, man screaming and running away …’
    Rincewind stepped down into the ditch and inspected the pipe-like device the man had been turning.
    â€˜It’s just a water-lifting screw,’ he announced. ‘I’ve seen a lot of them. You turn the handle, water is screwed out of the ditch, goes up the thread inside and spills out of the top. The screw makes a sort of line of travelling buckets inside the tube. There’s nothing special about it.It’s just basic … stuff.’
    â€˜Not psyence, then?’ said Ridcully.
    â€˜You tell me, sir,’ said Rincewind.
    â€˜Psyence is quite a difficult concept,’ said Ponder. ‘But I think perhaps tinkering with this thing to make it more efficient might be psyence?’
    â€˜Sounds like engineering,’ said the Lecturer in Recent Runes. ‘That’s where you try and make it in different ways to see if any of them are better.’
    â€˜The Librarian did turn up one book, very grudgingly,’ said Ponder, pulling it out of his pocket.
    It was called Basic Science for Schools, pub. 1920 .
    â€˜They’ve spelt it wrong,’ said Ridcully.
    â€˜And it’s not very helpful,’ said Ponder. ‘There’s quite a lot of what looks like alchemy. You know, mixing stuff up to see what happens.’
    â€˜Is that all it is, then?’ said the Archchancellor, leafing through the book. ‘Hold on, hold on. Alchemy is, at bottom, all about the alchemist. His books tell him all the stuff he’s got to do in order make things work – what to wear, when to wear it, that sort of thing. It’s very personal.’
    â€˜And?’ said the Lecturer in Recent Runes.
    â€˜Hark at this,’ said Ridcully. ‘There’s no invocations, nothing to tell you what to wear or what phase of the moon it should be. Nothing important. It just says here “A clean beaker was taken. To this was added 20 grammes” – whatever they are – “of copper sulphate” …’ He stopped.
    â€˜Well?’ said the Lecturer in Recent Runes.
    â€˜Well, who did the taking? Who added the stuff? What’s going on here ?’
    â€˜Perhaps it’s trying to say that it doesn’t matter who does it?’ said Ponder. He’d already glanced at the book, and felt that the perfectly ordinary ignorance he’d had just before opening it had been multiplied several times by page ten.
    â€˜Anyone can do it?’ shouted Ridcully. ‘Science is incredibly important but anyone can do it? And