Comment by int_19h a day ago
Like most other weird things in US that pertain to measurements and units thereof, letter-sized paper predates the A-series standard (which originated in Germany). FWIW the latter didn't became an ISO standard until late 20th century.
Americans are just very obstinate about those things. It's like the Windows of metrology - backwards compatibility trumps everything else, even when you have utterly bonkers things like ounces vs fluid ounces.
> Metric is already used in areas where it actually matters (e.g. STEM)
Using French Revolutionary units doesn’t really matter in STEM, either: one can conduct science just as well in any units one wishes. One unit of measure is not more scientific than another. For example, degrees Kelvin and Rankine measure the same thing with different units. If anything, the Rankine degrees are more precise!
You shouldn't use degrees for Kelvin, it's an absolute unit, the degrees are needed for the relative units like Celsius.
Anyway, the French system isn't what people mean by "metric" in this context, they mean the SI system of units, and so in practice it's not so much that it wouldn't matter which you choose as that you don't have any option except SI.
If you wanted an independent system of units you'd need to do a lot of expensive metrication, and in practice Americans are too cheap for that, so the US "customary" units are just aliases for so-and-so-much amount of some SI unit, they aren't actually independent at all.
The reason people focus on metric is that for everyday people that's the part which jumps out as more intuitive. All these nice powers of 10, very tidy.
> For T&E it really matters see NASA's Mars Climate Orbiter and the need for heroics in the Gimli glider.
> You need to keep to the same unit.
Completely agreed. You’ll get similar issues if you have one set of parts using m/s and others using km/hr.
And you’ll avoid those issues with any standard, whether it’s m/s, knots or mph. The important thing is to have a standard.
>Americans are just very obstinate about those things.
It's not just obstinance, switching everything to metric in the US would likely cost billions (if not trillions) of dollars. And other countries that have made the switch have often ended up with weird Frankensystems of measurement, like the UK where they mix metric and imperial all the time (plus the weird UK-specific measurements they have like "stone", which is based on the pound).
Interestingly, it's actually codified in US law that the metric system is the "preferred system of weights and measures for United States trade and commerce" -- however it wasn't a mandatory change so most industries didn't make the change, nor did the government.
https://en.wikipedia.org/wiki/Metrication_in_the_United_Stat...
Every single country in the world that is on metric today had to switch from something else at some point in the past. Why overfocus so much on UK when you have literally a hundred successful examples?
One does have to wonder what it is about Anglo countries specifically that makes it so difficult for them, though. Well, Canada at least has the excuse of being next door to US, with the resulting economic effects. For UK I'm pretty sure it's just about not being like "the Continent" at this point.
>Every single country in the world that is on metric today had to switch from something else at some point in the past. Why overfocus so much on UK when you have literally a hundred successful examples?
A huge percentage of those countries didn't have established industrial bases, infrastructure, etc. And also no educated general populace that needed reeducating. And often those countries were effectively forced into adopting metric through colonization and/or invasion.
Other countries switched. Short term pain for long term gain.
The trouble is there is just very little gain. It really just doesn't matter. All the systems are fine, they all work. If you come live here, you'll adjust after 2 years. If I moved to Europe, I would adjust in 2 years. Once in a blue moon you have to bother with converting units but c'est la vie. There's bigger things to worry about.
I've been living in US for 15 years now and I still can't remember which unit scales are factor-of-3 and which ones are factor-of-4. How many cups are there in a gallon? How many yards in a mile? I don't want to waste my brain cells on stuff like this, yet it comes up all the time in e.g. cooking, or using maps for navigation.
>Other countries switched.
Except they didn't actually, see my points about the UK (similar points apply to Canada).
It is a weird mix in the UK, distances are measured in miles, and speed limits are set in miles per hour, but fuel is sold in litres, for example.
People get very worked up about it too. People got very worked up about a government proposal to allow people to put imperial units on food in larger type than metric (at the moment it has to be metric larger - or at least the same size).
Everything in engineering and science has been entirely metric since the 80s.
Only road distances for cars are in miles and yards. The British railways continue to use chains (which are not used for any other ordinary activity) and non-road traffic is often in metres or kilometres as appropriate.
Some of those "Metric martyr" types, the kind of people who think anything which changed after they were 35 is an abomination, but somehow anything which changed ten years before they were born has never been any other way, will vandalize legal stuff which uses (in their opinion) the wrong units. So if you put a (legal and reasonable) 1.5km distance sign on a cycle route, but some car driver who thinks sane units are fascism sees it, they might smash it to pieces which is annoying.
There has been a very gradual lean towards sanity, after all my mother was taught decimal currency because it was forthcoming when she was at school, her parents had used a non-decimal currency system. When I was a teenager I still had coins which, though they were treated as their modern decimal value, if you read their faces had a non-decimal value printed on them, because it's too expensive to replace the currency when you switch.
When I was a child I would buy a quarter pound of sweets. At the turn of the century I'd ask for, and receive, 100 grams or 200 grams as I felt, but most customers would use pounds (although legally they'd be served in grams). These days everybody else would likely also ask in grams. So it's changing, it's just very slow.
The whole yard vs feet thing is especially weird. Indeed, in US as well, feet are normally used to measure sizes - at scales where it's reasonable - while yards are normally used to measure distances. Even though the two units are in the same ballpark / order of magnitude. And yes, as you rightly point out, it means that few people can estimate distances in feet.
OTOH on road sings, US at least seems to be using miles alone consistently, so you end up with labels like "1 3/4 miles" every now and then, which I find to be difficult to parse quickly.
The UK uses metric for almost everything. Miles/mph for driving and pints in the pub are the only things that are always non-metric. Human height and weight are the only other thing that is often non-metric, and even then a lot of people will know their weight in kg rather than stone.
For the UK in practice it is only distance measurements that are non metric now. For some things like small liquid amounts we colloquially use imperial - pints - which differ from US pints. I think the actual official volume is the metric it is just you could say slang that keeps to pints.
Anything to do with STEM is metric.
If you buy beer "loose" like at a bar it has to be sold in pints. Most people will have seen a "half" and anybody who likes stronger beers or goes to festivals where you taste different ones will know a "third" of a pint is also a legal amount of beer to sell. You would not want to try out a few different 8% stouts if they were sold only in whole pints, unless they're going to make it a multi-day event and provide somewhere for you to sleep it off.
Milk is also allowed to be sold in pints, traditionally glass bottle re-usable milk bottles were one pint.
It is also usual (but not legal) to sell a pint or a half of various soft drinks, in theory you should be sold these in some other way, I always say "large" or "small" but in practice ordinary people say "pint" and after all the staff will probably more or less fill a pint glass so, whatever.
Spirits (e.g. gin) are measured in either 25ml or 35ml shots. An establishment can choose either, post which one they picked and use that consistently. Why two seemingly unrelated sizes? Well, historically there were two different non-metric sizes permitted in law, and when the government legislated to make these SI units there were lobbyists demanding they allow this to continue despite the opportunity to rationalize.
As in the US, containers you purchase in a store are labelled, but here the labels must prominently show SI volume units and EU-style value metrics are required on shelf markings, so e.g. 10p per 100ml of Coke is a good price, maybe the Pepsi is on a deal for 9.5p per 100ml, the store's terrible own brand is 5p per 100ml. This EU strategy prevents people screwing with sizes to make you think you're getting a better deal, that cheaper bottle may look like a good idea but hey, it's 18p per 100ml, ah, it's slimmer in the middle which makes it actually much smaller than it looks.
Also, switching everything to metric is just not necessary. We already use the metric system all the time. We also use imperial.
Yes, so you have all the disadvantages and none of the advantages.
And sure, of course metric isn't necessary. You can also write all software in COBOL and PL/I. But over the long term, the convenience of having a self-consistent system based on a few simple principles rather than historical precedent adds up.
We are not particularly obstinate, we just have no strong reason to change. Metric is already used in areas where it actually matters (e.g. STEM)