Moving counterclockwise was considered moving in "the wrong direction." The Scots called this withershins, a movement associated with witchcraft.
Even today, when we're supposedly beyond superstition, our language is full of left-handed compliments--that is, insults--for southpaws. How do you describe someone who is really trusted and valuable to you? He's your right-hand man. What if you're a bad dancer? You have two left feet. Have you ever said, "How gauche" to describe something tactless? What you're really saying, in French, is "How left-handed." My favorite word for left, the Romany word bongo, means crooked or evil.
Even in English, though, we punish the southpaw. Take a moment to look at the Encarta dictionary entry for left-handed. Does it surprise you to learn that "clumsy" is one of the definitions of the term?
There are exceptions, of course. The Boy Scouts shake with their left hands. The official explanation for this is that it comes from an Ashanti custom where the bravest men shook left-handed, because it required them to put down their shields. But some experts in handedness point out, perhaps rightly, that the Boy Scouts' founder, Lord Baden-Powell, supported the Ambidextral Culture Society in England. He might have had an ulterior motive for encouraging the left-handed greeting.
When you stop to think about all of this, it's really bizarre. Our left and right hands look more or less alike. It takes several years of practice for most of us to even distinguish between left and right. I can distinctly recall going to kindergarten with my shoes on the wrong feet. So, why the bias against the left hand?
I have no idea. But my thinking did lead me to some very interesting tidbits of information.