A father gathers his three sons and tells them sadly

— Kids, in the night some asshole stole our cow.

Oldest son (OS): An asshole? He must be short.

Middle son (MS): Short guy? He must be from the next village.

Youngest son (YS): From the next village? Who else but Jimmy?

So the sons go to the next village and beat the shit out of Jimmy. Naturally, he takes the matter to the local court.

The judge asks the sons why the thought it was Jimmy.

OS: Well, our father told us that some asshole stole our cow, and if he's an asshole, he must be short.

MS: If he's short, he must be from the next village.

YS: If he's from the next village, he must be Jimmy.

Judge: Hmmm, that's some interesting logic there - I wonder if it's valid. You there, bring me the box sitting over there. Now boys, can you deduce what's inside?

OS: The box is square.

MS: If it's square, what's inside must be round.

YS: If it's round, it must be an orange.

The judge opens the box, takes out an orange and tells Jimmy: C'mon, man, give them back the cow!

EDIT: changed some wording, credit to /u/Lamenardo