So my friend Dave went to San Francisco for a few weeks, and while he was gone he asked our mutual friend Pete and I to check in on his cat--feed it and all that. Pete was the primary champion of this cause.

About the fourth day, Pete called me at my office, which was just down the street. "You're not gonna believe this," he said. "Dave's cat is gone."

I rushed up there and we canvassed the apartment, and sure enough, the cat was gone. We went over the facts: the door had been locked when Pete had gotten there--logical since he had locked it when he'd left the day before--all the windows were closed, and there was no other way out of the second floor apartment. We performed an exhaustive search to locate the missing feline, but it became evident she was no where to be found.

Finally, when all seemed lost, I noticed the ceiling tile above the refrigerator was slightly askew. Fearing the cat somehow had climbed up there, I investigated. I could see the expansive array of pipes and wires across the huge second floor, covering many apartments. No sign of the cat.

Of course, it was the only way the cat could have escaped. We left, and Pete called Dave. Dave called me right after, all upset. He was convinced Pete had left the door unlocked the day before and the cat had gotten out--that, or the landlord had come in without notice and let the cat out. "Dave," I said, "the cat went out through the ceiling. I'm sure of it."

He argued it. "That fat cat couldn't possibly have gotten up on the fridge," he said, and it seemed sensible.

I paraphrased Holmes: "I'd normally agree, but when all else has been eliminated, the only possibility remaining, no matter how improbably, must be it."

"No, Pete left the door open," he said stubbornly.

Neither Pete nor I could convince him otherwise. Pete and I knew the truth, and posted a sign in the lobby of the building. Within two hours, the lady in the next apartment called my office reporting she had the cat--that she had heard a tremendous crash in her bedroom closet and when she opened it, there was the cat and the ruins of a ceiling tile.

Needless to say, Dave could hardly believe it, and he was at least humbled by the fact he had insisted Pete had to have messed up. We enjoyed teasing him immensely. However, I took the cat home with me to keep a close eye on her. She had my two cats for company and was able to attack my dog, so things were better.

But, of course, it couldn't end there. The second day the cat was at my house, I found Dave on ICQ and sent him this message:

"I don't quite know how to tell you this, but... Your cat disappeared from my apartment, Dave."

"You're kidding me" he typed back.

"No, I'm not. We're pretty sure she escaped using a circular saw to cut through the back room wall.  There is a big hole there and lots of sawdust, cut from INSIDE the bedroom... outside, on the grounds, six estate guard dogs--three Dobermans, two Rottweilers, and a toy poodle--were found mauled to death by some sort of feline."

"Very funny," he replied.

"All that obvious evidence aside, though, I think Pete came over to my house and accidentally cut the wall out himself.  He has a habit of doing that."

"Okay, Dave," he said.

"Pretty @&*$ing irresponsible of him, but that's just the way he is. I've seen him do it before. We'd stop over to a buddy's house, and Pete, while carrying on a conversation, would suddenly pop his goggles on, plug in his portable pocket circular saw, and start cutting away. Never even realize he did it, either."

"I GET the POINT, Dave!"

But who could resist keeping it going? The next day, on ICQ, I found him again.

"Your cat has escaped from a maximum security stockade.  She's baffled all the authorities... apparently she has some sort of latent super power that enables her to cut through solid steel with just a look. Heat vision, I think."

"Right..." 

"But Pete had just been in during visiting hours and I think he probably just left the cell door open when he left."

Dave was not amused. I dared to try for a third attempt, the following day.

"Dave, your cat is on the news.  Apparently she grew to the size of a 12-story building and clawed up City Hall and ate the mayor.  They're mobilizing National Guard troops now ... it was that Pete, you know... he was absent-mindedly spraying a hose full of Miracle-Gro on her, the dumb bastard."

It was at that point that Dave officially ceased being even the tiniest bit amused—or patient, or a good sport—and who can blame him?

And the moral of the story is: don't make assumptions, lest your friends tease you forever.