Once upon a time a man of a certain age, who lived in a certain town, met a dragon.
"Dragon," he said, "May I take you home and keep you as a pet?"
"O honored sir," said the dragon (for dragons are very polite), "I think, rather, I will tear your flesh, splinter your bones, and scatter your limbs across the valley floor."
This gave the man some occasion for thought. "Dragon," he said, "Perhaps we could be friends, like, instead."
The dragon answered, "Perhaps we could, honored sir. But I am rather hungry and it might be thought that your respected self was not altogether polite. So I think on the balance it would be better for me to eat you."
"Honored Dragon," said the man, "Maybe I have not understood things very well. I am an ignorant man and one does not meet many dragons, in my trade. Maybe you could take me home as a pet, instead?"
"I am infinitely obliged to you for the offer, sir, but my circumstances are not such as conduce to the care of pets. You would pine, I think, honored sir, without proper feeding and exercise; and I should hate to see you grow thin and stringy." The dragon licked its lips.
"Most Reverend Dragon," said the man, "I think I have been mistaken about a great many things."
"That may well be so," said the dragon. Then he tore the man to pieces and ate him.
"Not a clever man," he mused, as he cracked the last bones to suck the marrow. "But at the end there he was learning to be polite."