Ruth This one

“We're dealing here," said Vimes, "With a twisted mind."
"Oh, no! You think so?"
"Yes."
"But... no... you can't be right. Because Nobby was with us all the time."
"Not Nobby," said Vimes testily. "Whatever he might do to a dragon, I doubt if he'd make it explode. There's stranger people in this world than Corporal Nobbs, my lad."
Carrot's expression slid into a rictus of intrigued horror.
"Gosh," he said.”
― Terry Pratchett, Men at Arms: The Play

“Don't wish, Miss Tick had said. Do things.”
― Terry Pratchett

“Why do you go away? So that you can come back. So that you can see the place you came from with new eyes and extra colors. And the people there see you differently, too. Coming back to where you started is not the same as never leaving.”
― Terry Pratchett, A Hat Full of Sky

“Silverfish looked down.
"Oh. Are you a dwarf?"
Cuddy gave him a blank stare.
"Are you a giant?" He said.
"Me? Of course not!"
"Ah. Then I must be a dwarf, yes.”
― Terry Pratchett, Men at Arms: The Play