Last week I was struggling to put a stack of papers into a three-ringed binder and found myself wishing I had an extra hand. Then I got to thinking if I had an extra hand (or really an extra arm with a hand attached), where on my body would be the best place for it?
As a SF writer I can create a character who has three arms/hands, but where would be the most practical place for that extra appendage? In the center of the torso, front side? That would be handy (sorry for the pun), but it would make sleeping difficult for tummy sleepers. That would be the same problem for a third limb on the back. And if my character needed to use it in front of him, it would have to be longer than side arms to reach around his body. Think however, how easy it would be to scratch your back (or bum).
So where else–two on one side? I wouldn’t mind having two dominant hands, so have two arms on the right side would be fine with me. Ideally, I’d like to have a dominant hand on each side. Then I could use both sides of my brain at the same time. Can people who are completely ambidextrous use both both sides of the brain concurrently?
Can you imagine a character with a third arm attached somewhere else, say hip or head, or knee? Not sure of any advantages with any of these places, and frankly, it’s hard to imagine.
I can hear you asking, why not a character with four arms; two on each side? And why not; it’s SF after all.