The belief is believed to have arisen after the black death, about a century after many other simalar snezing superstitions. As such, it is one of the few that doesn't involve bad luck.

Although its exact origion is obscure, it is believed to have evolved from an earlier superstition, that of when your right ear burns someone is speaking good of you, left ear, bad. [I gues Devan's lucky he's a turtle or he'd have a permenant earache.]