In retrospect the gram / kilogram thing is clearly a design flaw. Interestingly the basic unit is the kilogram; and if Wikipedia is correct in an early version of the system the basic unit was the grave (about 1 kg.) Too late to change it now!
I didn't know about the grave ! Interesting !
Ares and hectares are horribly confusing. I think they made sense in a largely agricultural society (such as 1790s France.)
Maybe it has something to do with how measurements of area work well when the exponent is 2, but not with 3. sqrt 100 = 10, but sqrt 1000 = ~31.622. So the are was chosen so e=2 (hectare) would be useful for farming, and e=-2 (centare) would be useful for carpentry.
That reminds me of two more complaints about the are (Note: Did you read "are" wrong ?):
(1) It's abbreviation "a" looks like a common english word.
(2) The capitalized version "A" is already the abbreviation for amps.
(...) mills (...)
I didn't know that "mills" were a thing. That reminds me that in japanese, "senchi" are used as a shortening for centimeters (
https://jisho.org/search/senchi )
- Litres are a bit too big; having a drink-sized unit is useful
I'm not so sure. To this day, despite being American, I still have only a vague sense of how much a tablespoon, (fluid) ounce, or pint is (a cup somewhat more so), and definitely couldn't tell you how many of each make up the next largest measurement, but I've done enough chemistry and science to have a good sense of how much 1 milliliter is, and prefer to measure things with it. Perhaps this would be good enough motivation to start using centiliters? (1 oz = 2.957 cL)
A tangent: The glass I'm drinking out of at this very moment lists its size on its bottom as "20oz / 600ml". Note the incorrect use of small "l" for liter. It's more proof that making units and prefixes case sensitive was a bad idea. Case is not respected often enough in non-scientific/academic contexts to rely upon it to differentiate critical things like units.
Pre-submission Addendum: According to this (
https://www.bipm.org/documents/20126/41 ... hure_8.pdf ), apparently lower case "l" is fine for liters now!??? Maybe this is a recent change ? I remember being explicitly strongly taught in middle school that it's *always* *upper case* "L", so it doesn't get confused with "1".
5/6/7/ are and ton are not international system units (m² and 1x103kg)...
It's not SI, but it's still metric, and widely used.
Before I read your post, I didn't even know about the m/M distinction, and I've used the metric system for all my life.. And how does the sign in the photo you posted cause confusion? What else could "KM" mean in that context?
Sure, it's clear for "KM", but what about "MG"? Does it mean milligram or megagram? Taking a milligram of a drug vs a megagram is quite the difference. Sure, you'll probably be able to tell the difference by context, because a milligram is so light that you don't feel it, and a megagram is so heavy you need at least a dolly to move it, but if you're designing a system of measurement, surely you want to make it clear and avoid relying on context at all.
Outside of engineering, who ever uses "micro"?
Medicine, nutrition, computing.
I think some of the smaller things in daily live, such as individual pieces of small consumer electronics, are closer in scale to grams than to kilograms. Anyway, a lot of food is sold in amounts smaller than a kilogram, so grams are practical measurements for it: The phrase "a 750 gram bread" is shorter than the phrase "a 750 milligram bread".
Think of something that's about a meter or two long. Is it closer in weight to a gram ?, or to a kilogram ?
You mean, as opposed to the words "foot" and "yard", which have no meanings outside of measurements? Anyway, as far as I can tell, few people ever use "ares", so I don't see where the problem is.
But they're pronounced the same, and are the same part of speech as the unit, so you don't get led down a garden path.
I have never heard this. Kilometres are shortened to "kay"s.
I suppose I've heard this in America too: The "5K" race, which means 5 kilometers, which is about 3.1 miles. It applies to other race lengths too: 10K, 20K, but I thought it was a racing thing, not a general length thing; I wouldn't expect somebody to say they're driving "sixty-seven kays" to their grandma's house for a holiday, for example.
"klicks" in US military slang.
I remember hearing that. If metric ever catches on in America, I hope it becomes more popular. "kilometers" is a chunky 4 syllables to say, but "klicks" is a quick 1 syllable.
I don't know anyone who can reliably feel the difference between 22C and 23C
I don't know if I could tell the difference between 22 C and 23 C, but I can definitely tell the difference between 20 C and 22 C. Last year, I would set my apartment to 72 F (22.222 C) (the perfect temperature, imo), then my roommate would change it to 68 F (20 C), and I would get cold and wonder why I'm suddenly shivering, and go look at the thermostat and see that it's been changed, so I'd change it back.
That said, I wouldn't mind if America switched from using fahrenheit to celsius. Of all the possible units that could be switched, temperature would probably be the easiest. The reasons about being unable to switch because of "precision" strike me as just making up "reasons" when the real reason is because they're just used to fahrenheit. (Is there a pithy term for this kind of "reasoning" ?) After all, with this kind of logic, shouldn't Americans be eager to start using centimeters instead feet and inches to measure their height? ~~Centimeters are more precise, after all!~~
Another thought: The naming of paper sizes in ISO 216 is confusing: An A4 paper fits into a B4 envelope. All good. Therefore, a B4 paper fits into a C4 envelope, right? Wrong! C4 is actually larger than A4, but *smaller* than B4. But at least I understand the reason why: the A and B series were invented first, and it wasn't until 100 years later that someone invented the C series, when they realized that they wanted a size inbetween the A and B series. It's still slightly annoying, nevertheless.
Also, wouldn't it make more sense for the larger sizes to have the larger numbers, and the smaller sizes the smaller numbers? It would also make the system extensible. Right now, it's the opposite: A0 is larger than A1, A1 is larger than A2, etc. What if I want a paper that's twice the size of A0? What do I call it? A negative one?
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Please note that my criticisms of the metric system are not meant to imply that I see America's current system of measurements as superior. They are just an honest criticism of a system, which like any other system, is imperfect and full of vestiges and compromises. Indeed, I wish America did use the metric system on a wider scale, though I doubt it will ever fully switch.
