Crusty Paul sat in his apartment, water lapping at his feet, when there was an insistent knock at his door.  He sighed and got up to answer it, knowing full well it was Larry, his annoying neighbor from downstairs.  He opened the door, and sure enough, there was Loopy Larry, a look of stern admonition on his insipidly righteous face.

“There’s water dripping on my head again, Paul,” he said.

“Well, I’ve told you before, just get used to it.”

Loopy Larry sighed.  “Have you let the bath run over again?”

A flush rose to Paul’s face.  “So what?  It’s just your stupid theory that that’s what’s making water drip on your head.”

“It’s not just a theory.  Every time it happens, I come up here and you’ve let the bath water run over.  Look at your floor, for chrissake, it’s covered with water!”

Paul looked at him with an expression of someone explaining some simple fact to a rather dense child, for the hundredth time.

“If you look at the past, you’ll see there are lots of times when water just falls out of the sky, for no reason.  How can you say my bathwater causes your problem, when we know that happens naturally, all the time?”