Comment by saalweachter
2 days ago
The creators of metric weren't above buggering it to fit human scale needs.
Take the length/weight relationship.
Definitionally, it'd be way more elegant for the unit of mass to be based on the unit of length directly, a cubic meter of something, but having your base unit of mass be a ton wasn't going to fly.
So they instead tried for 1/100th of the meter and landed on the gram, but it turns out they misjudged and now your standard unit of weight is the prefixed kilogram instead, because everyone used kilograms instead.
Which is to say, if you didn't get a pretty good paper size out of the definition used for A0, someone would have found a different definition which did produce a pretty good paper size, and then declare it was the only natural one.
I don't think anybody loses sleep over the kilogram issue because, well, it's metric after all. A kilogram is exactly 1000 grams, so the gram is just as perfectly well defined. Nothing would really change if they were to promote the gram to be the standard unit of mass (not weight!) someday.
I am annoyed by it. We should be using gravs instead. Then there would not be this special unique unit with prefix as base unit.