Occasionally it has fallen upon me to ask people what hand they use to get about in life. Typically this is in the context of trying to determine someone’s handedness prior to teaching them to fence.
The answer is never simple. “I write with my left hand but eat with my right hand.” “I do everything right handed except for dealing playing cards.” “Oh, I’m ambidextrous. Except for writing, using tools, picking my nose, scratching, picking things up, carrying things, and a couple other times — then I always use my right hand.”
That kind of thing.
So — at least in the context of determining handedness for using a sword, I’ve come up with what I hope is a simple and definitive line of inquiry:
“What hand do you use to brush your teeth?”
I’ve found this is a pretty good one, for a few reasons. First, it’s simple. There’s always a clear and unambiguous answer. (Almost: see below.) Second, my assumption is that there isn’t a lot of direct instruction given in hand selection when it comes to brushing teeth. So you’re likely to get a more accurate assessment of true handedness than you do by asking what hand the person writes with. (A lot of people have historically been forced to switch to right-handed writing even if they’re naturally lefties. But I’d assume that in tooth-brushing one would be naturally inclined to use the hand that is most capable overall.) Third, the action of brushing teeth requires a balance of strength, endurance, and dexterity that — no joking — I think is a reasonably good model for fencing, so the hand they use for brushing their teeth is a good choice for using a sword.
Finally, back to the “almost” above. When I asked my Dear Wife this question, she looked at me like I had two heads, and said, “What are you talking about?” So I repeated the question: what hand do you brush your teeth with?
“Whichever hand it’s easier to reach that side of the mouth with, duh.”
And that’s how I discovered that my wife is truly ambidextrous.
So there you go. One question you can ask that will identify fencing-appropriate handedness without confusion, and which will also accurately identify the natively ambidextrous. It’s great fun at parties, I’m sure.