In the column Why do we say a pair of pants when theres only one of them, I don’t think Cecil actually answered the question.
The closest he comes is saying
The obvious next question is why pants are in this category, but Cecil ignores that, and goes on to discuss “pairs of rosary” and “a pair of stairs”.
Early pants/trousers/breeches were paired leggings; sometimes they could be nothing but stockings, depending on how far the upper garment descended below the waist. Modern trousers that, at first glance, seem to be a single piece of cloth are quite recent.
Wouldn’t it have been a good idea for Cecil to mention that in the column?
Some of the other “pair” objects were originally in two parts, and only later were permanently fastened together, such as tweezers (evolved from two sticks used like oversize chopsticks, to two sticks tied together, to various wood/metal items permanently fastened into a single object).
…and the “pair of stairs” bit is oddly coy for Cecil. I am left to assume (with a little help from Slug’s illustration) that the theatrical feature in question is the same one referred to in the Firesign Theater gag “She’s got a balocony you could do Shakespeare from!”
No, “pair of stairs” was definitely common in the early modern period and into the 19th century or so. It is usually explained by staircases of the sort that go up half a story, turn around, and then go up the other half.
What about scissors? It’s hard to imagine they could work without being joined, and we always call them a pair too.
You can’t imagine a use for a single shearing blade?
Powers &8^]
Stabbing someone?
Shearing is something that kinda needs two surfaces. Cutting only needs one blade, but scissors don’t necessarily have cutting edges.
The earliest scissors were spring scissors made of a single piece of metal (old-fashioned sheep shears are the last survival that I know of), but pivot scissors have been around for thousands of years. They are at least made in two parts that are then joined.
Well, consider an old-fashioned tabletop paper cutter, which has only one blade but shears rather than slices.
Regardless, I’m sure it developed as a plural because there are two blades, even if the applications for just one of the blades in isolation are limited.
And contrary to Allan Sherman, there’s no such thing as “a single scis.”
Powers &8^]
The ones I have seen have two blades - one blade is on the swinging arm and one blade is on the platform, but the two edges work in concert to shear.
For a cross national view on the matter, in Norwegian pants come in pairs, scissors and tweezers do not.
Outside of primitive agriculture methods or collecting souls, no 