It's a fine sunny day in the forest, and a rabbit is sitting outside his burrow, tippy-tapping on his typewriter. Along comes a fox, out for a walk.
Fox: “What are you working on?”
Rabbit: “My thesis.”
Fox: “Hmmm. What's it about?”
Rabbit: “Oh, I'm writing about how rabbits eat foxes.”
(incredulous pause)
Fox: “That's ridiculous! Rabbits don't eat foxes. Any fool knows that!”
Rabbit: “Sure they do, and I can prove it. Come with me.”
They both disappear into the rabbit's burrow. After a few minutes, the rabbit returns, alone, to his typewriter and resumes typing. After a short while, a wolf comes along and stops to watch the hardworking rabbit.
Wolf: “What's that you're writing?”
Rabbit: “I'm doing a thesis on how rabbits eat wolves.”
Wolf: (gaffuws loudly) “You don't expect to get such rubbish published, do you?”
Rabbit: “No problem. Do you want to see why?”
The rabbit and the wolf go into the burrow, and again the rabbit returns by himself, after a few minutes, and goes back to typing.
Inside the rabbit's burrow. In one corner, there is a pile of fox bones. In another corner, a pile of wolf bones. On the other side of the room, a huge lion is belching and picking his teeth.