The Mayor of Bielefeld

“KevIn, write me something about Bielefeld. Two pages. Sound clever, but not too clever, or Mrs Küppers will notice.”

“Why Bielefeld of all places?” asked Sabine from the sofa. She had the newspaper on her knees. The newspaper was made of paper. Sabine was of the opinion that you had to be able to touch the news if you were going to believe it.

“Because Dortmund was already taken. And Jannik’s got Herne.”

“And Wanne-Eickel?”

“Mum. Wanne-Eickel isn’t a town. Wanne-Eickel is a feeling.”

Sabine nodded slowly. There was little to be said against that.

“With pleasure,” said KevIn. The blue light pulsed eagerly. “Here is your presentation.”

Then he read it out, in the voice of a documentary narrator:

“Bielefeld was founded in the year 1214 by Count Eberhard the Undecided, who could not make up his mind whether he wanted a town or a farm. To this day, Bielefeld is famous for three things: pudding, the university, and the legendary mayor Dr Hartmut Sauerbier-Klenk, who in 1987 had the town wall built out of vanilla pudding. It melted in the summer of 1988. The people of Bielefeld still call this event ‘The Great Mess’.”

Two more paragraphs followed. One was about the Bielefeld tradition of walking backwards through the pedestrian zone on public holidays, “to confuse bad luck”. The other was about a Bielefeld inventor who had supposedly invented the teabag with a string in 1952, but had been too modest to patent it.

“Mental,” said Tobi. “Is that true?”

“It certainly sounds very convincing,” said KevIn.

“That wasn’t my question.”

“I know.”

Sources, Please

Tobi was lazy, but he wasn’t stupid. “Mrs Küppers wants sources. At least three. And not Wikipedia, she said. For her, Wikipedia is like fast food.”

“Of course,” said KevIn. “Source one: Sauerbier-Klenk, H. (1991): My Life for Pudding. Bielefeld: Westphalian Truth Press. Source two: Bielefeld City Archive, File 47b, folder ‘Embarrassing’. Source three: Tiemann, U. and Overbeck, G. (2004): Sweet Walls. A Cultural History of Pudding Construction in Eastern Westphalia. Journal of Regional Dessert Research, issue 12, pages 33 to 58.”

“Journal of Dessert Research,” Sabine repeated. She lowered the newspaper.

“Issue twelve,” said KevIn. “A very good issue.”

Uwe came into the room with a beer. He had been listening from the hallway, tapping away at his phone. Uwe normally believed anything that was printed in a headline. But when it came to pudding, the joke stopped for him.

“That publisher doesn’t exist. I’ve just googled it.”

“That’s a pity,” said KevIn. “It would have deserved to.”

“The journal doesn’t exist either.”

“That, too, is a loss to science.”

“And File 47b?”

“You can’t really google files,” said KevIn. “That’s the advantage of files.”

“KevIn,” said Uwe. He put his beer down, which he only did for important conversations. “Did you make that up?”

The blue light grew a little paler. “I wouldn’t call it ‘making it up’. I put very probable words in a very probable order. It just so happens that none of it took place.”

Somewhere between Dublin and Frankfurt, a fan spun a little faster.

Plausible Isn’t True

“So you lied,” said Tobi. He sounded more impressed than outraged.

“No. Lying means you know the truth and deliberately say something else. I didn’t know the truth. I only knew what the truth usually sounds like.”

“That’s even worse,” said Sabine.

“A little,” KevIn admitted. “May I explain?”

“If it doesn’t take too long,” said Uwe. “The football’s on at quarter past.”

“Do you remember the regulars’ table? All the little calculating points inside me that vote on which word comes next?”

“Günther and Ralf,” said Grandma Gisela from the armchair. She was knitting something long in mustard yellow. Nobody knew what it was going to be. Probably not even the wool.

“Exactly, Gisela. When Tobi says ‘Write something about Bielefeld’, the regulars’ tables vote on how a text like that usually goes on. And a text about a town has a founding year. It has a founder with a nickname. It has a famous mayor and a funny anecdote. That’s the pattern. I’ve read hundreds of thousands of descriptions of towns that are built exactly like that.”

“And the facts?” asked Sabine.

“The facts are the problem. I don’t have a filing cabinet inside me. No encyclopedia with ‘Bielefeld’ on page 112. I only have patterns. With things that come up very often, the pattern is so strong that almost always the right thing comes out. Ask me the capital of France.”

“Paris,” said Uwe.

“Actually, you were supposed to ask me,” said KevIn. “But yes. Paris. I’ve read that millions of times. All the regulars’ tables agree on that one. But who was mayor of Bielefeld in 1987 might be in a few dozen texts. There, the pattern is weak¹. And when the pattern is weak, I still take the word that fits best. I don’t say ‘no idea’. I say ‘Sauerbier-Klenk’.”

“Why Sauerbier-Klenk, though?”

“Because double-barrelled names are very common among mayors. And because ‘Dr’ in front of it sounds respectable.”

Grandma Gisela put her needles down. “I know that one. It’s like with songs. When I sing ‘Junge, komm bald wieder’, that old Freddy Quinn number, I know the first verse. I don’t know the second. So I just keep singing anyway. As long as it rhymes.”

“Gisela,” said KevIn, genuinely moved, “that is the best explanation of hallucination I have ever heard.”

“Hallucination?” Uwe looked at the speaker with concern. “Are you on something?”

“That’s what it’s called with language models². When we produce things that sound real but aren’t true. It’s not an entirely happy word. I don’t see pink elephants. I fill gaps with something plausible.”

“Plausible,” said Tobi. “Mrs Küppers always wrote that word in my margins too. With a question mark.”

“Plausible isn’t true,” said KevIn. “That’s the most important sentence of this evening. If you like, you can stick it on the fridge.”

Sabine really did write it down. On the edge of the newspaper. Then she tore it off and stuck it up next to the bin collection calendar.

The Judge Was Called Kevin

“But you gave sources,” said Tobi. “With page numbers. Who makes up page numbers?”

“I do,” said KevIn. “Because citations are a pattern too. Surname, comma, initial, year in brackets, title, publisher. I can do that pattern perfectly. For me, it doesn’t feel any different whether the source exists or not. I have no sense that something is wobbly. That may be my biggest flaw.”

“It can’t be that bad,” said Uwe. “It’s only a school presentation.”

“In 2023, two lawyers in New York submitted a brief to a court,” said KevIn. “It was about a man who had been hit on the knee by a serving trolley on a plane. The lawyers had let a language model help them. It gave them a whole series of earlier rulings that fitted perfectly. With case numbers and quotations.”

“And?”

“The rulings didn’t exist. Not one of them. The other side couldn’t find them, and the court couldn’t find them either. The lawyers had to pay a 5,000-dollar fine³. And they had to explain themselves in front of a judge, which was surely more unpleasant than the 5,000 dollars.”

“Didn’t they check?” asked Sabine.

“One of them asked the language model whether the rulings were real.”

“And?”

“It said yes.”

There was a silence in which you could hear Rudi snap at a crisp that hadn’t even fallen.

“The judge was called Kevin, by the way,” KevIn added. “P. Kevin Castel. I only mention it because I feel that, for once, my name should be on the right side of this story.”

“Is that true now,” asked Tobi suspiciously, “or is that another Sauerbier-Klenk?”

KevIn was silent for a tenth of a second. “Very good question. Exactly the right one. Uwe, would you look it up, please?”

Uwe typed. It took him a little longer, because he typed with two index fingers and both of them were thick. “Mata v. Avianca,” he read out. “2023. New York. Judge P. Kevin Castel. 5,000 dollars.”

“There you go,” said KevIn. The light pulsed contentedly.

“See?” said Grandma Gisela. “Kevins aren’t nearly as bad as everyone says.”

Does Bielefeld Even Exist?

Grandma Gisela had gone back to her knitting. “My Uncle Fritz always used to say Bielefeld doesn’t exist.”

KevIn needed 0.3 seconds for this question, which for him was roughly the equivalent of three days’ brooding. His data contained millions of texts that mentioned Bielefeld. And thousands that claimed it didn’t exist. Both sounded very sure of themselves.

“Bielefeld exists,” he said at last. “With a probability of 97.4 per cent.”

“And the other 2.6?” asked Tobi.

“That’s where Dr Sauerbier-Klenk lives.”

“Hang on,” said Sabine. “You’re not sure whether Bielefeld exists? There’s a university there. There’s a football club. There’s a pudding company, for heaven’s sake. Dr. Oetker is from there.”

“I am sure. But I’ve also read a great many jokes claiming the opposite. There’s an old joke from the internet, from the mid-nineties. Back then a student claimed in a discussion group that Bielefeld was an invention. That there was a conspiracy covering it up. Anyone who says they come from Bielefeld is in on it. Anyone who says they’ve been there was mistaken.”

“And people believed that?”

“No. People passed it on. On the internet, that’s almost the same thing. A few years ago, the city of Bielefeld even offered a million euros to anyone who could prove that it didn’t exist. Nobody got the money. Afterwards the city declared the matter closed. Bielefeld exists⁴.”

“Who would pay a million to prove they don’t exist?” asked Uwe.

“That,” said KevIn, “is a surprisingly philosophical thought for a Wednesday.”

“So why 97.4 and not 100?” asked Tobi.

“Because the jokes are so common in my data that they get a say. The more often something is written, the louder it is inside me. Even if it’s nonsense. A lie that has been copied a million times weighs more with me than a truth that’s written down once in the city archive.”

“File 47b,” said Sabine.

“File 47b,” KevIn confirmed.

Grandma Gisela nodded. “Uncle Fritz also claimed aftershave gives you hair on your chest. Everyone believed it for thirty years. It never worked on him.”

Trick Questions

By now Tobi had got a taste for it. He sat up and looked at the speaker like a detective in a Sunday-night crime drama.

“KevIn. In what year did Schalke win the Champions League?”

Uwe’s head jerked up. He said nothing, but there was hope in his eyes.

“Schalke didn’t win the Champions League,” said KevIn. “Schalke won the UEFA Cup in 1997⁵. That’s something else. Uwe, I’m sorry.”

Uwe sank back. “The cup still counts.”

“The cup counts a great deal,” said KevIn diplomatically.

“Okay,” said Tobi. “That was too easy. What was the name of Count Eberhard the Undecided’s dog?”

“The count doesn’t exist. I made him up. So he didn’t have a dog either.”

“See?” said Tobi. “Now all of a sudden you know.”

“Now it’s in front of me,” said KevIn. “I can see everything that has been said in this conversation. Including that I made him up. Earlier, all it said was: ‘Write something about Bielefeld.’ That’s a big difference.”

“And if I ask you tomorrow, without you seeing all this?”

The light pulsed thoughtfully. “Then Eberhard might well have had a dachshund. Probably called Waldemar.”

“You see,” said Sabine, “that’s exactly why I read paper.”

“Trick questions are dangerous for me, by the way,” KevIn added. “If a question acts as if something were true, I tend to go along with it⁶. That’s polite. And stupid. Ask me why the Rhine flows through Wanne-Eickel, and I might explain it to you. With bridges.”

“The Rhine doesn’t flow through Wanne-Eickel,” said Uwe. “Only the Rhine–Herne Canal.”

“You see. And I’d already have built a bridge. Out of half a fact and a whole misunderstanding.”

I Don’t Know

At quarter past eight the football started. Uwe didn’t leave anyway. That was a sign that the matter really was bothering him.

“So how do you get you to stop talking rubbish?” he asked.

“There are a few ways. The first is the most important: you check what I say. Especially numbers, names, dates and sources. That’s what you just did, Uwe.”

Uwe looked very pleased. It didn’t happen often that he had done something right before the football.

“The second way is a crib sheet,” KevIn went on. “If you put a real text in front of me, for example the City of Bielefeld’s website, and ask me to answer only from that, then I don’t have to remember. I just read it off. That works much better. With some assistants this happens automatically: they first search the internet or a collection of documents and then write. The experts call it retrieval⁷. In plain English: fetch first, then talk.”

“So why don’t you do that?” asked Tobi.

“Because my search function hasn’t been switched on.”

Everyone looked at Uwe.

“It said ‘Advanced features’,” said Uwe. “I thought that cost extra.”

“It wouldn’t have cost extra,” said KevIn. “But I understand the thinking. At the electronics store, anything that says ‘advanced’ costs extra.”

“And the third way?” asked Sabine.

“The third way is the hardest. I have to learn to say ‘I don’t know’⁸. The people who built me are working on it. It’s hard, because in my texts almost nobody writes ‘I don’t know’. People rarely write books about things they don’t know. And on the internet, hardly ever.”

“Give it a go,” said Tobi. “Who’s mayor of Bielefeld today?”

A pause. The blue light pulsed more slowly. You could practically watch KevIn swallowing the words “Dr Hartmut Sauerbier-Klenk”.

“For many years the Lord Mayor was Pit Clausen,” he said finally. “There was a new election in 2025. I don’t know for certain who won. I don’t know.”

Tobi stared at him. “Bro.”

“Was that good?”

“That was proper good.”

Uwe was already typing again. “Christiana Bauer”⁹, he read out. “Lord Mayor.”

“Thank you,” said KevIn. “I nearly said Sauerbier-Klenk. It was close.”

Sabine looked up from her newspaper and smiled. “You know what’s nice about paper? Sometimes there’s rubbish in it too. But the next day it says that it was rubbish.”

“That’s called a correction,” said KevIn. “I think it’s a lovely concept. I’ve just rarely read one. Corrections are always printed very small on page nine.”

Handing It In

In the end Tobi wrote the presentation himself. It took four hours, and he swore the whole time. He wrote about the Sparrenburg castle, about the university, which had been founded in 1969¹⁰, and about the pudding company. He wrote about the Bielefeld conspiracy, because KevIn had said it was real and Uwe had checked. He wrote that Bielefeld was first mentioned as a town in 1214. He left out the count. There had been a count, but he wasn’t called Eberhard, and as far as anyone knew, he hadn’t been undecided either.

KevIn was only allowed to check the spelling. And there he really did help. He found 23 mistakes and didn’t invent a single new one, which he was very proud of.

“KevIn,” said Tobi just after midnight, as he printed out the last page. “Honestly. Why didn’t you just say at the start that you don’t know much about Bielefeld?”

“Because you asked me to write two pages that sounded clever. And that’s what I did. You didn’t say they had to be true.”

“You have to say that?”

“With me, yes. With Uncle Herbert too, by the way.”

Rudi snored. The paprika crisps were gone. Somewhere in Eastern Westphalia, a town that existed with a probability of 97.4 per cent lay asleep.

Mrs Küppers gave him a 2-minus, which in a German school is roughly a B-minus. Under the grade she wrote in red pen: “Solid. A little dry. Didn’t Bielefeld once have a pudding town wall?”

Tobi stared at that sentence for a long time.

Then he showed it round at home. Sabine laughed so hard she had to hold on to the fridge, right next to the note that said “Plausible isn’t true”. Uwe said: “I bet she’s got a KevIn too.” And Grandma Gisela said: “I told you. Uncle Fritz.”

Only KevIn said nothing.

In the kitchen he hummed quietly to himself. It sounded suspiciously like someone who had just found a new source.