Ponder prided himself that he knew pretty much all there was to know about electricity. But they'd tried rubbing balloons and glass rods until they'd been able to stick Adrian onto the ceiling, and it hadn't had any effect on Hex. Then they'd tried tying a lot of. cats to a wheel which, when revolved against some beads of amber, caused any amount of electricity all over the place. The wretched stuff hung around for days, but there didn't seem any way of ladling it into Hex and anyway no one could stand the noise. So far the Archchancellor had vetoed the lightning rod idea. All this depressed Ponder. He was certain that the world ought to work in a more efficient way. And now even the things that he thought were going right were going wrong. - He stared glumly at Hex's quill pen in its tangle of springs and wire. The door was thrown open. Only one person could make a door bang on its hinges like that. Ponder didn't even turn round. 'Hello again, Archchancellor.'

'That thinking engine of yours working?' said Ridcully. 'Only there's an interesting little---'

'It's not working,' said Ponder. 'It ain't. What's this, a half-holiday for Hogswatch?'

'Look' said Ponder. Hex wrote: +++ Whoops! Here Comes The Cheese! +++MELON MELON MELON +++ Error At Address: 14, Treacle Mine Road, AnkhMorpork+++ !!!!! +++Oneoneoneoneoneone +++ Redo From Start +++ 'What's going on?' said Ridcully, as the others pushed in behind them. 'I know it -sounds stupid, Archchancellor, but we think it might have caught something off the Bursar.'

'Daftness, you mean?'

'That's ridiculous, boy!' said the Dean. 'Idiocy is not a communicable disease.' Ridcully puffed his pipe. 'I used to think that, too,' he said. 'Now Im not so sure. Anyway, you can catch wisdom, can't you?'

'No, you can't,' snapped the Dean. 'It's not like 'flu, Ridcully. Wisdom is ... well, instilled.'

'We bring students here and hope they catch wisdom off us, don't we?' said Ridcully. 'Well, metaphorically,' said the Dean. 'And if you hang around with a bunch of idiots you're bound to become pretty daft yourself,' Ridcully went on. 'I suppose in a manner of speaking . . 'And you've only got to talk to the poor old Bursar for five minutes and you think you're going a bit potty yourself, am I right?' The wizards nodded glumly. The Bursar's company, although quite harmless, had a habit of making one's brain squeak. 'So Hex here has caught daftness off the Bursar,' said Ridcully. 'Simple. Real stupidity beats artificial intelligence every time.' He banged his pipe on the side of Hex's listening tube and shouted: 'FEELING ALL RIGHT, OLD CHAP?' Hex wrote: +++ Hi Mum Is Testing +++ MELON MELON MELON +++ Out Of Cheese Error +++ !!!!! +++ Mr Jelly! Mr Jelly! +++ 'Hex seems perfectly able to work out anything purely to do with numbers but when it tries anything else it does this,' said Ponder. 'See? Bursar Disease,' said Ridcully. 'The bee's knees when it comes to adding up, the pig's ear at everything else. Try giving him dried frog pills?'

'Sorry, sir, but that is a very uninformed suggestion,' said Ponder. 'You can't give medicine to machines.'

'Don't see why not,' said Ridcully. He banged on the tube again and bellowed, 'SOON HAVE YOU BACK ON YOUR ... your ... yes, indeed, old chap! Where's that board with all the letter and number buttons, Mr Stibbons? Ah, good.' He sat down and typed, with one finger, as slowly as a company chairman: D-R-Y-D-F-R-O-R-G-½-P-I-L-L-S Hex's pipes jangled. 'That can't possibly work sir,' said Ponder. 'It ought to,' said Ridcully. 'If he can get the idea of being ill, he can get the idea of being cured.' He typed: L-O-T-S-O-F-D-R-Y-D-F-R-O-R-C-P- ¼-L-L-S 'Seems to me'

' he said, `that this thing believes what it's told, right?'

'Well, it's true that Hex has, if you want to put it that way, no idea of an untruth.' `Right. Well, I've just told the thing it's had a lot of dried frog pills. It's not going to call me a liar, is it?' There was some clickings and whirrings within the structure of Hex. Then it wrote: +++ Good Evening, Archchancellor. I Am Fully Recovered And Enthusiastic About My Tasks +++ 'Not mad, then?' +++ I Assure You I Am As Sane As The Next Man +++ 'Bursar, just move away from the machine, will you?' said Ridcully. 'Oh well, I expect it's the best we're going to get. Right, let's get all this sorted out. We want to find out what's going on.'

'Anywhere specific or just everywhere?' said Ponder, a shade sarcastically. There was a scratching noise from Hex's pen. Ridcully glanced down at the paper. 'Says here “Implied Creation Of Anthropomorphic Personification”,' he said. 'What's that mean?'

'Er ... I think Hex has tried to work out the answer,' said Ponder. 'Has it, bigods? I hadn't even worked out what the question was yet . . .'

'It heard you talking, sir.' Ridcully raised his eyebrows. Then he leaned down towards the speaking tube. 'CAN YOU HEAR ME IN THERE?' The pen scratched. +++ Yes +++ 'LOOKIN' AFTER YOU ALL RIGHT, ARE THEY?'

'You don't have to shout, Archchancellor,' said Ponder. 'What's this Implied Creation, then?' said Ridcully. 'Er, I think I've heard of it, Archchancellor,' said Ponder. 'It means the existence of some things automatically brings into existence other things. If some things exist, certain other things have to exist as well.'

'Like... crime and punishment, say?' said Ridcully. 'Drinking and hangovers ... of course. . 'Something like that, sir, yes.'

'So ... if there's a Tooth Fairy there has to be a Verruca Gnome?' Ridcully stroked his beard. 'Makes a sort of sense, I suppose. But why not a Wisdom Tooth Goblin? You know, bringing them extra ones? Some little devil with a bag of big teeth?' There was silence. But in the depths of the silence there was a little tingly fairy bell sound. 'Er ... do you think I might have---' Ridcully began. 'Sounds logical to me,' said the Senior Wrangler. 'I remember the agony I had when my wisdom teeth came through.'

'Last week?' said the Dean, and smirked. 'Ah,' said Ridcully. He didn't look embarrassed because people like Ridcully are never, ever embarrassed about anything, although often people are embarrassed on their behalf. He bent down to the ear Hex again. 'YOU STILL IN THERE?' Ponder Stibbons rolled his eyes. 'MIND TELLING US WHAT THE REALITY IS LW ROUND HERE?' The pen wrote: +++ On A Scale Of One To Ten Query +++ FINE,' Ridcully shouted. ++ Divide By Cucumber Error. Please Reinstall Universe And Reboot +++ 'Interestin',' said Ridcully. 'Anyone know what that means?'

'Damn,' said Ponder. 'It's crashed again.' Ridcully looked mystified. 'Has it? I never even saw it take off.'

'I mean its ... its sort of gone a little bit mad,' said Ponder. 'Ah,' said Ridcully. 'Well, we're experts at that around here.' He thumped on the drum again. 'WANT SOME MORE DRIED FROG PILLS, OLD CHAP?' he shouted. 'Er, I should let us sort it out, Archchancellor,' said Ponder, trying to steer him away. 'What does “divide by cucumber” mean?' said Ridcully. 'Oh, Hex just says that if it comes up with an answer that it knows can't possibly be real,' said Ponder. 'And this “rebooting” business? Give it a good kicking, do you?'

'Oh, no, of course, we ... that is ... well, yes, in fact,' said Ponder. 'Adrian goes round the back and ... er ... prods it with his foot. But in a technical way,' he added. 'Ah. I think I'm getting the hang of this thinkin' engine business,' said Ridcully cheerfully. 'So it reckons the universe needs a kicking, does it?' Hex's pen was scratching across the paper. Ponder glanced at the figures. 'It must do. These figures can't be right!' Ridcully grinned again. 'You mean either the whole world has gone wrong or your machine is wrong?'

'Yes!'

'Then I'd imagine the answer's pretty easy, wouldn't you?' said Ridcully. 'Yes. It certainly is. Hex gets thoroughly tested every day,' said Ponder Stibbons. 'Good point, that man,' said Ridcully. He banged on Hex's listening tube once more. 'YOU DOWN THERE---'

'You really don't need to shout, Archchancellor,' said Ponder. -what's this Anthropomorphic Personification, then?' +++ Humans Have Always Ascribed Random, Seasonal, Natural Or Inexplicable Actions To HumanShaped Entities. Such Examples Are jack Frost, The Hogfather, The Tooth Fairy And Death +++ 'Oh, them. Yes, but they exist,' said Ridcully. 'Met a couple of 'em myself.' +++ Humans Are Not Always Wrong +++ 'All right, but I'm damn sure there's never been an Eater of Socks or God of Hangovers.' +++ But There Is No Reason Why There Should Not Be +++ 'The thing's right, you know,' said the Lecturer in Recent Runes. 'A little man who carries verrucas around is no more ridiculous than someone who takes away children's teeth for money, when you come to think about it.'

'Yes, but what about the Eater of Socks?' said the Chair of Indefinite Studies. 'Bursar just said he always thought something was eating his socks and, bingo, there it was.'

'But we all believed him, didn't we? I know I did. Seems like the best possible explanation for all the socks I've lost over the years. I mean, if they'd just fallen down the back of the drawer or something there'd be a mountain of the things by now.'

'I know what you mean,' said Ponder. 'It's like pencils. I must have bought hundreds of pencils over the years, but how many have I ever actually worn down to the stub? Even I've caught myself thinking that something's creeping up and eating them---' There was a faint glingleglingle noise. He froze. 'What was that?' he said. 'Should I look round? Will I see something horrible?'

'Looks like a very puzzled bird,' said Ridcully. 'With a very odd-shaped beak,' said the Lecturer in Recent Runes. 'I wish I knew who's making that bloody tinkling noise,' said the Archchancellor. The oh god listened attentively. Susan was amazed. He didn't seem to disbelieve anything. She'd never been able to talk like this before, and said so. 'I think that's because I haven't got any preconceived ideas,' said the oh god. 'It comes of not having been conceived, probably.'

'Well, that's how it is, anyway,' said Susan. 'Obviously I haven't inherited . . . physical characteristics. I suppose I just look at the world in a certain way.'

'What way?'

'It ... doesn't always present barriers. Like this, for example.' She dosed her eyes. She felt better if she didn't see what she was doing. Part of her would keep on insisting it was impossible. All she felt was a faintly cold, prickling sensation. 'What did I just do?' she said, her eyes still shut. 'Er . . . you waved your hand through the table,' said the oh god. 'You see?'

'Um ... I assume that most humans can't do that?'

'No!" 'You don't have to shout. I'm not very experienced about humans, am l? Apart from around the point the sun shines through the gap in the curtains. And then they're mainly wishing that the ground would open up and swallow them. I mean the humans, not the curtains.' Susan leaned back in her chair - and knew that a tiny part of her brain was saying, yes, there is a chair here, it's a real thing, you can sit on it. 'There's other things,' she said. 'I can remember things. Things that haven't happened yet.'

'Isn't that useful?'

'No! Because I never know what they - look, it's like looking at the future through a keyhole. You see bits of things but you never really know what they mean until you arrive where they are and see where the bit fits in.'

'That could be a problem,' said the oh god politely. 'Believe me. Its the waiting that's the worst part. You keep watching out for one of the bits to go past. I mean I don't usually remember anything useful about the future, just twisted little dues that don't make sense until it's too late. Are you sure you don't know why you turned up at the Hogfather's castle?'

'No. I just remember being a ... well, can you understand what I mean by a disembodied mind?'

'Oh, yes.'

.'Good. Now can you understand what I mean by a disembodied headache? And then, next moment, I was lying on a back I didn't used to have in a lot of cold white stuff I'd never seen before. But I suppose if you're going to pop into existence, you've got to do it somewhere.'