"Well, the Earth Mark Two in fact," said Slartibartfast cheerfully. "We're making a copy from our original blueprints."
There was a pause.
"Are you trying to tell me," said Arthur, slowly and with control, "that you originally ... made the Earth?"
"Oh yes," said Slartibartfast. "Did you ever go to a place ... I think it was called Norway?"
"No," said Arthur, "no, I didn't."
"Pity," said Slartibartfast, "that was one of mine. Won an award you know. Lovely crinkly edges. I was most upset to hear about its destruction."
"You were upset!"
"Yes. Five minutes later and it wouldn't have mattered so much. It was a quite shocking cock-up."
"Huh?" said Arthur.
"The mice were furious."
"The mice were furious?"
"Oh yes," said the old man mildly.
"Yes well so I expect were the dogs and cats and duckbilled platypuses, but ..."
"Ah, but they hadn't paid for it you see, had they?"
"Look," said Arthur, "would it save you a lot of time if I just gave up and went mad now?"
For a while the aircar flew on in awkward silence. Then the old man tried patiently to explain.
"Earthman, the planet you lived on was commissioned, paid for, and run by mice. It was destroyed five minutes before the completion of the purpose for which it was built, and we've got to build another one."
Only one word registered with Arthur.
"Mice?" he said.