Make the Metric system the standard in the United States | Hacker News Reader

Make the Metric system the standard in the United States

petitions.whitehouse.gov

820 pointsovechtrick530 comments

It's obviously a great idea, and obviously (to Americans) unlikely to happen in the lifetime of anybody reading this forum.

Does anybody else from America remember being taught the metric system in public elementary school, and being told that we'd be switching to it over the next few years? I was taught this around second grade (1981), I think based on the Metric Conversion Act of 1975 (http://en.wikipedia.org/wiki/Metric_Conversion_Act), which was not just signed by some random interweb tubers -- it was signed into law by the president. But IIRC, it was a toothless and impotent piece of legislation that was effectively stymied by the US auto industry.

P.S. Amusing visual evidence that the US system sucks:

http://cdn.zmescience.com/wp-content/uploads/2011/03/metric-...

Sorry, but how is that picture evidence that the US system sucks? I don't disagree that we have a poor system, but "everyone else is doing it" has never been a justification to do anything!

If everyone else was using tcp/ip would it be sensible to continue using ipx/spx?

yeah, if you wanted to keep the hackers out

Ask Sony how well security through obscurity's been working out for them.

Every time one of the red countries does business with the grey countries, there's conversion deadweight.

We should all have one currency too, then?

Of course not: sovereign currencies have well-known benefits. Multiple systems of measurement are only a hindrance, a friction.

The friction of unit conversion is much lower, though, because they are constant and don't have transaction fees. The number of centimeters per inch or pounds per kilogram is the same today as it will be next month or next year.

...actually NASA proved that kind of friction to be very severe: http://articles.cnn.com/1999-09-30/tech/9909_30_mars.metric_...

Just think that it also could have affected people...

Actually, that's the reason that most international trade is done in dollars.

Currency is backed by different governments, and they have different risks, rates of inflation, etc. We're just talking about measuring things.

I'm guessing you're quite unfamiliar with the metric system. The different types of measurements are defined in relation to one another and are thus easy to figure out, unlike the imperial system where everything is odds and ends.

A kilogram is (almost exactly, but slightly different) to the mass of one litre of water. The force required to accelerate this mass at one metre per second squared is one Newton. One Newton acting on one square metre is one Pascal of pressure. Applying a force of one Newton through a distance of one metre is one joule of energy. This is the same amount of energy in passing a one ampere current of electricity through a resistance of one ohm for one second. One joule per second is one Watt.

Yep - I remember being told in 4th or 5th grade (which would be 1975ish) that we all had to learn the metric system because the country was converting.

And here we are 35 years later...

I'm about the same age and went through the same education, although it was probably a bit earlier.

It did come in handy when taking science courses in high school. Everything we did was in metric, from chemistry to physics. I don't know if American high schools ever taught things like physics in English measurement in years prior, that must have been a nightmare.

I actually remember when the metric system was introduced in elementary schools.

Looking back, there was far too much emphasis on getting all prefixes and their relationships memorized: micro, milli, centi, deci, hecto, kilo, mega. And virtually no emphasis on developing an intuitive "metric" feel for the common quantities in everyday life.

Amusing visual evidence that speaking English sucks: http://cnrsociety.org/images/English-Official_Map-s.png

This would be a great analogy if countries in grey shared a common language.

There's a difference between "A vs. B" and "A vs. Not A"

>1/6 is a rather sizable fraction of the world's population (India itself is ~1/6 or 1/7 at over a billion people). Are there any other languages that are official for so many people?

The metric system graphic indicates <1/6 of the world's population highlighted as not using the metric system, making gp's point stronger.

> Are there any other languages that are official for so many people?

Yes, Chinese for one. And Spanish closely follows English[1]

[1]: http://en.wikipedia.org/wiki/List_of_languages_by_total_numb...

The map's wrong to the extent it implies the USA has an official language. We have a de facto standard language, but we have no laws defining an official language.

And that's even funnier because Canada (as well as "the African ones") English isn't the only standard language. Canada for example has French as well as English, and Africa, well that depends which one. But it certainly isn't 100% English.

Much better visual evidence: http://signword.files.wordpress.com/2012/02/423399_101506340...

Pretty weak argument for Celsius. Why should people care that the boiling and freezing points are simple? That is almost irrelevant for the most common uses of temperature reporting. People care about the ambient outside temperature (which Fahrenheit seems optimized for), not the effect it has on the state of one particular compound.

Kelvin should be the logical choice for temperature: http://en.wikipedia.org/wiki/Kelvin

... or not: http://www.nature.com/news/quantum-gas-goes-below-absolute-z...

People care for various temperatures:

- weather (Celcius has the advantage that just from the temperature you know if there will be snow and ice/will snow melt, or no) And you won't know the difference of 1 C anyway, so no point in having so small degrees.

- temperature of human body (are you sick or not - it's 36.6 C for healthy human, 40 C for dangerous temperature) - here Fahrenheit has slight advantage, because human body temperatures are near 100 F, IIUC.

- temperature for cooking (water boils in 100 C, you make tea with 80 C, most cakes bake at 220 C, etc) I think Fahrenheit is worse there.

- temperature for science/engineering (Kelvin rules here, but Celcius is just Kelvin - 273.15, so conversion is much easier than Fahrenheit, differences are same in K and C).

There is a point in having small degrees, in that small fluctuations in the weather are more noticeable. I can say that the weather will be in the 60s today, and people will know what I mean, but saying it will be in the 20s today (in celcius) offers a much larger range of weathers to be had.

Also, you can tell just as easily if something melts using Fahrenheit, you check whether it's above or below 32. Sure, it might seem a little arbitrary, but it's just as arbitrary as "36.6 C is healthy" or "cakes bake at 220", which people seem to remember just fine.

This is the reason why nobody ever would say "in the 20s" when giving a temperature in celsius. Instead people either say "about 25" or give a range ("20 to 25"). The size of units change how people express themselves.

Yeah, never understood the "problem" with Fahrenheit. When I ask people to tell me why Celsius is better, many will tell me because its "decimal", and then I point out to them it is no more decimal than Fahrenheit, there are no "kilodegrees". They will then point out the water freezing/boiling, as if they regularly have to set that temperature to accomplish that (you don't, you just put water in the freezer or a kettle on the stove). Celcius is annoying from a practical perspective because you have less degrees to deal with in every day temperatures, and in Fahrenheit 0 is "cold" and 100 is "hot" (vs like -20 to 40).

It's "better" because it's just an offset Kelvin scale. So when you're doing delta calculations, there's no difference. And really, most temperature calculations are relative.

Fahrenheit is just an offset Rankine scale.

Does anyone actually use the Rankine scale?

In Celsius, a negative temperature means snow instead of rain, or icy streets instead of wet. Whether the ambient temperature is below freezing is pretty useful knowledge, and more clearly expressed in Celsius.

As for the difference between 16 and 17 degrees, the only people who give a shit are people who know how to use decimals for their measuring purposes. In everday use, the finer gradation of the Fahrenheit scale are irrelevant.

The way to know whether it is going to snow or rain is to check the weather report, mainly because more factors go into that than just the temperature (for example, amount of moisture in the air, cold/warm fronts, etc -- which can lead to anything from snow, hail, sleet, or freezing rain). I imagine you are generally getting your temperature from a weather report anyways (unless you are looking at some sort of personal thermometer before heading out the door?) so the information will be presented to you there alongside it, not requiring you to do any mental calculus to figure this out yourself.

It's not about whether it will snow or rain, it's about whether precipitation will be frozen or not, and all you need to know that, for precautionary reasons, is the temperature. It's not a large advantage of Celsius, but it is pervasive.

ETA: To be clear, I'm Canadian, and grew up with Celsius. Whether the temp was positive or negative was the second thing worth knowing after the actual number. It was a very practically useful bit of knowledge in everyday life, easily given and easily remembered.

Fahrenheit is not really optimized for that either. It's basically optimized for "still positive in the coldest days in Denamrk some 200 years ago, and less than 100 in the warmest days". (Seriously)

If you live in e.g. San Diego, it goes from ~60 to ~90. If you live in NYC, it goes from ~25 to ~100. That's not more optimized than Celsius, which goes from ~15 to ~30 and ~-4 to ~35 respectively.

However, when in NYC, you know that negative celsius means black-ice out in the street; zero celsius mostly means snow, and positive celsius means non of the above.

Also, you know that 1kcal that you get from food (or Con Edison) will heat one liter of water by one degree celsius (and a quart is a good approximation for a liter, if you're still in NYC ...)

Here is the thing: Created for still positive for the coldest days in Denmark and under 100 for the warmest is optimizing for ambient outdoor temperature. And much more human readable than heating one liter of water etc. I am not saying it is perfect, but I don't see why it shouldn't continue to be used as it is currently: F for weather reports and such while using C/K for more scientific pursuits.

Yet, it's quite handy that Celsius is based on the freezing temperature of water in winter. You always now when you'll have ice on the streets, cars, etc. :)

Remembering that 32 is freezing is not taxing and gives you the same amount of information (i.e., almost none because temperature alone is a poor predictor of weather).

The freezing temperature matters far less than you think. There is "latent heat" that must be added to ice to make it melt and removed from water to make it freeze.

Just the other week we had a wintry mix of precipitation at a nice and balmy 0.5 C which resulted in accumulated snow and ice, despite never being below freezing at ground level. It even warmed up through the day slightly to 1.7 C or so but the ice and snow never completely melted as there wasn't enough heat to overcome the latent heat of vaporization needed.

And as mentioned elsewhere, it's not exactly difficult to remember "32 F is freezing", even the most dense Americans have figured that out so it's another metric solution to a problem that doesn't actually exist in America.

Please be aware that Celsius is not a SI unit, Kelvin is used in stead as the standard temperature unit. The only reason why many people use Celsius is because it makes sense in their daily lives. The melting and boiling point of water are both important in cooking and the freezing point is also important for the weather. Therefore it makes a lot of practical sense to use Celsius and people have stuck to it even though it is not an SI unit.

Water's freezing point is easily the single most important temperature there is when it comes to (outdoor) temperature. Essentially, it tells you whether travelling is a deadly hazard or not. It tells you whether to expect snow or rain (which require quite different types of clothes). At least for those of us living in places with snow (as Celsius did), there's no more sensible thing to base the temperature scale on.

When it comes to boiling point, yeah I can give you that it's perhaps not as obviously the right thing. But it's the logical other end of the scale, and most of us do care about it several times daily, when cooking.

Even when I'm cooking I never care about the temperature of my water in Celsius, especially since 1) its exact boiling point will vary depending on the air pressure of my present location, and 2) impurities in my tap water (as well as my standard metric pinch of salt) will alter the boiling point of the solution.

So while I do really adore the metric system, the gp's argument still stands: Fahrenheit just so happens to coincidentally peg 100 somewhere near "too damn hot" and 0 to "too damn cold", and I don't see why civilians would benefit from mandating that weather reports be specified in Celsius (and I'd honestly rather prefer Kelvin than Celsius).

It's not weak at all. I don't know about you, but I'm surrounded by decimal measure systems and I find other old/weird legacy systems brain-damaging (please don't bother mentioning exceptions, I'm aware of their existence even in the metric system territory). I prefer the centigrade over something else anytime. The fact that Celsius have chosen 0 and 100 for for freezing and respective for boiling normal water in normal atmospheric pressure outweighs any other possible reference in regard to its relevance to a human.

I'll sum up for you: normal water, normal pressure, normal reference-peeking, and normal and logical 100-sized interval reference.

EDIT: fixed a typo

mm/dd/yy makes sense to those who use it, given our cultural adjustment.

My father's argument for imperial is how easy it is to divide measurements. In woodworking, especially. 10 is divisible by 2 and 5. Powers of two are more flexible for division.

Does your father change units each time he needs to divide something?

Only between feet and inches, but usually, he's working solely in inches (and fractions of an inch) for his projects.

I didn't get how using inches is easier here. Can't you also do all these calculations, with the same ease, using centimeters?

Ease of use with imperial? I say no way. Trying to add 1/16 and 1/5 is somewhat harder than mm addition.

That's why you don't cut to 1/5...

I suppose it's all numbers in the end.... Mankind has found a way in the rest of the world to make metric work!

That's why plywood in Europe is usually sold in sheets of 240 cms, i.e. 2.4 m, which seems easier to calculate with, in particular when adding lengths.

Put a tape measure along a sheet of plywood and prepare to be surprised. At least then you'll know why you always had trouble fitting them :)

DD/MM/YYYY doesn't make any sense either unless you write numbers with the most significant digit on the right. Only YYYY/MM/DD actually makes sense (which is why lexicographic sorting automatically works when you use it).

"that was effectively stymied by the US auto industry."

Do you have a source for that? Not implying its false.

Ironically if you've worked on an auto built from the 90's (maybe even 80's (man I'm old)) onward, you'll find a confusing mix of standard and metric fasteners often within the same components - doors, etc.

Most of the comments in this thread are talking about the units for personal height, weight, local road signs or for the weather forecast. Those are by far the least important things to be worried about. All of those things are local and there is no carrying cost for them. There would be a cost to change all those signs and forecasts - for no real gain.

However, dimensions of physical goods are a constant recurring cost to the economy. Anything that crosses the borders for trade (all resources mined/farmed, everything manufactured) has to be dealt with in both sets of units. There is massive redundancy in fasteners, components, scales, paperwork, etc. It requires companies to keep two sets of tools (and not just wrenches, also drills, taps, dies, cutters, etc).

Good point. In Canada, we still use imperial measures for body height and body weight, and many older folks still talk in miles and fahrenheit.

But everyone adjusted to metric for less personal weights and measures, and other abstract measures.

Pretty good compromise, I think.

Another Canadian here (Maritimer). With temperature I find many people talk about the weather in Celsius but the temperature of their homes/thermostats in Fahrenheit. Swimming pools also measured in Fahrenheit.

Gym weights, except in Olympic lifting competition, everyone talks lbs.

While in the UK I noticed everyone measures weight in stone (1 stone = 14 lbs).

Yes. The gym weights I found in the UK where in kg, though.

I used to think in stone. But I don't need to know my weight very often and when I do it's usually for ski bindings at european resorts - so now I find myself thinking in kilograms.

The only non-metric unit that I think in now is miles - and there are obvious safety/legal problems in switching our speed limit road signs to kilometers.

No, everybody will be going just a tad slow for a while.

Good consternoon affable. No, I thought this speedo was in KPH.

hehe, you owe me a new keyboard :) tx

I agree the examples are irrelevant. A better example (from my experience) would be the oil/gas/chemical industry where you have millions of miles, oops kilometers, of pipes, uncountable valves, fittings, sensors, vessels, etc. What's the counterpart to a 6", sch 60 pipe? You definitely do not just convert to metric!

My favorite nonsensical (not-quite-non-dimensional unit)? Heat rate: MMBtu per MWh

Another nonsensical conversion? MMCF to MMBtu or, worse, 10^3m^3 to MMBtu.

The gain would be psychological. If people use metric units in day-to-day things, the rest will fall out naturally.

THe 'sets of tools' argument is kind of spurious. I already have a box full of wrenches; I'd need some more in the box. Nobody argues 'lets get rid of 5/32 bolts, so I can get rid of that wrench'.

Its the mental effort to rationalize them that is the real cost. Lets see, slightly larger than 1/4 - is it 7mm? or 8? or 9/32?

When I had the tires on my buell motorcycle changed the guy here in germany only had metric wrenches. He had to "fix" one to get the wheel of.

I was talking about the factory floor. Even if we switched to metric tomorrow, you would still need wrenches to work on things made before the switch.

But cutting tools are consumable. You need new drills, taps, dies, and cutters all the time. Manufacturers have to stock twice as many because of metric and imperial. Those are big ticket expenses.

I agree that it is all about cost, however this is far more "local" to many US citizens than they might imagine. For example, most of the coke bottles outside of the US come in half litres, while in the US they come in 20 fluid ounces (this is certainly true for many other products, too.) Hence, companies that make coke filling machines must accommodate the imperial system on top of the metric system, as well. Given that the metric system company can easily grab most of the market share, it should eventually be able to get larger economies of scale. In the end, it could very well be that machinery to supply imperial unit sized products becomes more expensive, a cost that will most certainly be relegated to the consumer.

That would probably work if the US economy wasn't so big. In reality, it isn't until you get to niche products that it will be possible (and ay have happened); anything as mainstream as a Coke bottle will be fine in imperial.

Quite right. I just finished a civil engineering degree and found that despite the vast amounts of published academic research and literature from the US, the use of imperial units rendered a very large proportion virtually unusable. Its an inherently empirical subject and continual conversion was both incredibly tedious and introduced a likely source of error (you get "an eye" for metric units so you can quickly tell if you are obviously an order out from where you should be).

Before we start with the standard junk about "imperial measures are better because they are easier to understand / better suited to human scale / etc." can I say nope.

The only advantage that imperial measures have (for some) is that they are familiar. That's the sum total of it. People where were raised metric find these apologies for imperial measures to be pure gibberish.

Aren't their much easier to use? Conversion between units is straight-forward, there is connection between length and volume units, and probably much more common-senses-ness. I mean, the ft+inch system for human height is absolutely horrible.

Actually, I think metric could be improved with a few imperial equivalents - A "metric foot" as 30cm, for instance - because they are convenient measurements.

e.g. If somebody asks me "How tall is that person?" it's easier to say "About five foot" rather than "I dunno, about 155cm?"

(I'm British, btw)

On Spain we just say "one fifty five", not much longer and it's still easy.

Then you would end up: "Not about, how exactly tall he is?", "Oh, five foot and 5 cm."

The 30cm unit would improve absolutely nothing, it would only complicate things. If you want to use approximate measurement, just round it to tens of centimeters. Or you can use meters with one decimal place, whatever comes more natural.

> If you want to use approximate measurement, just round it to tens of centimeters

I totally agree. Rounding to powers of ten works comes for free in metric measurements using base ten numbers. This is by design.

I only live in Metric-using country and I have no slightest idea how tall is five foot, whereas 155cm instantly comes to my mind as, ah, at around my eye level. It's all about familiarity.

Sure, but that's 3 digits versus 1; if the requirement is to express common, human sized-objects with rough accuracy in as few words as possible, it works just fine. Really, it's all semantics (as you say), but there are specific cases where one might be a better fit than the other. It's the inconsistencies in imperial that are truly horrible, not the arbitrary standard unit...

Incidentally, I was raised metric-only in Germany and we would often say "I'm one head shorter/taller than X", which is close enough to a foot.

How about 5ft7 vs 170cm. The later seems easier to express to me. If only rough accuracy is required then you only really need to take note of the first two digits. Incidentally converting between the two is quite messy; first you must learn that 1ft = 12 inches, then multiply the 5 by 12 then add 7 then multiply by 2.54. Where as to convert a metric figure to imperial, it does not matter so much whether you are starting out in metres or centimetres.

> Sure, but that's 3 digits versus 1

It isn't, really. If asked about my approximate height, I'd say 'eins-achtzig' ie 1.8m (notice me omitting the unit), which in practice also has only a single significant digit (or 2 if you account for tall people) and to me isn't any more unwieldy than '6 foot'.

This is only because you're british and because of the way you learned how to measure things when you were young.

I'm totally unable to represent in my head how really tall "about five foot" is whereas 1,50m is totally understandable for me, easy to visualize.

I was educated during the conversion in the UK and commonly switch between the two. Speed and distances for travel in miles, shorter distances in meters. Height in feet for people, meters for building etc. Weight of people in stone, otherwise normally grams, liquids in pints for some things, liters for others.

It's confusing, but makes sense in the long run.

> It's confusing, but makes sense in the long run.

You're perceiving things like this because it's what you were brought up with. None of the examples in which you claim it's "natural" to use imperial units make any sense to me at all. I don't think in miles, don't know how much a "stone" is, and pints are just pure confusion - which pint? there's about 4 types isn't there?

It's what you grew up with, nothing more.

Yes but getting the transition from one to the other takes a long long time.

I'm in England, and I view 500ml as a "metric pint"

Yes, let's add another set of measurements, that sounds like a great idea.

It's our age, I'm afraid. I'm a foot'n'inch-using brit too, but my early teenage kids only deal in metric units (except for miles)

My parents used pounds, stone, feet and inches; my school used kg, g, and cm (born in ’80). I’ve had to take a conscious decision to reset my thinking to metric only and to supply metric values when people ask for them.

This all apart from miles of course, but when all your road signs are in miles and the speed limits in mph there’s not much you can do about that. Who knows what plans there are for that switchover…

How does that even work - do you actually draw a mental image of yourself walking up that person's length foot by foot?

And what if your feet are not 30cm, but longer or shorter?

If you say "about x" you might as well estimate to 10cm precision and say "about 180cm" or "about 190cm".

People complain about the usual issues: multiple definitions of a mile, the odd ratios between inches, feet, yards, etc. It gets even more fun in agriculture, where the bushel is a frequently used unit. Now, the bushel is a unit of volume, whereas much of the world prefer to measure their crops by weight. To convert between the two, you essentially need to use conversion ratio (or table) for the crop type, along with an estimate of the moisture content of your product. To be fair, this is more to do with a difference in measuring methodology, rather than a failure of the imperial system, but it still highlights the kind of issues that come up between the systems.

More info: http://en.wikipedia.org/wiki/Bushel

Why not use metric volumes instead of bushel? You'd have the same conversion issues converting bushel to imperial weights.

Well, at some point, that part of the world decided that they'd use weight to measure produce, as opposed to volume. So now, if you read a scientific paper from Europe, you will get numbers in KG, likely with no indication of moisture content (since they don't particularly care). So, you're left with an inaccurate conversion to bushels, or more likely, you simply don't use the paper. The same goes for the other way around; there's probably a whole lot of rework that happens due to this incompatibility.

I get the problem, my point was just that it is unrelated to the issue of imperial vs metric system.

This is fairly similar to fuel mileage, where some places use miles per gallon (distance per volume) while others use litres per 100km (volume per distance). Changing systems is fairly irrelevant though, since you can still measure your mileage in kilometres per litre if you want.

No, it's different. distance / volume vs volume / distance are just inverses. Weight vs Volume are completely different measures and can only be compared by knowing the specific properties of the contents. Some recipe books have conversion tables for using depending on _what_ you're measuring.

My point is that changing the units doesn't have to change how you measure it. You can measure in kg or L just as easily, it's literally a number conversion. Whether or not you change how you measure it is a much more localised form of standardisation.

To be honest, although I know the obvious benefits of metric, I still prefer imperial simply because of its messiness. I realize the system is archaic, etc., but I still like that connection, as attenuated as it may be, to our ancient past. Use metric for all scientific purposes, etc., but keep that connection to the natural world.

I suppose I like it in the same way I prefer natural languages to some artificial languages like Esperanto, etc. - or our base-60 time units as opposed to some other decimal-based system. :)

Sentiment is not a good justification in the science/engineering world.

Is there a large contingency of people in the science and engineering world not using metric?

Like a previous commenter said, all my science labs in high school and college used metric. I imagine legitimate research and engineering labs in America are also using metric.

Civil and a lot of Mechanical still use standard. Especially for machining and such. We also used kips (kilopounds) in my Statics class.

Well, it seems that NASA, at least a few years ago, did not consistently use metric ...

NASA may have learned a hard lesson that time.

That's great that you feel that way but a unit systems is suposed to efficiently communicate information. Using an archaic unit system because it makes you feel hipster isn't a good idea.

In the year MMXIII is sentiment really a good reason to continue using an inefficient system :)

At least a better reason than in the year MXMIX (or in the year MMXLII :)

Those numbers are used for Superbowls, not years. Get it together!

No! MMXII is the guy who owns the copyright to all movies from last year.

After some time agonising over those in the last year, I can assure you they're still used for Superbowls and years, as well as name ordinals and many other things :)

Have you seen the people on Mythbusters flail about while trying to convert using units like inch-pounds and miles per hour and fluid ounces to cubic feet? There's a reason science insists on using the metric system.

The metric system is relatively ancient, dating from the late 1700s.

A system of measurements dating back 300 years is not ancient by any sane scale. It's still the newcomer to the set of systems of measurement.

Considering the amount of scientific discovery since that point, yes, it is ancient. Surely 90% of our scientific knowledge has come past the point in which it was invented.

It's a load of fun until you try to create an international website selling clothes, or food recipes, or even has dates on it.

We 've already settled on using English for everything on the net, why not settle on common language about measures too.

>We 've already settled on using English for everything on the net

You understand that you're just saying this in an english-speaking world and if there is anything against your argument it just won't come up here at your feet?

I 'm not from the English-speaking world and that holds for a huge number of people here and in the wider internet. English was the lingua franca before the internet and is the default language of the internet. Using it guarantees that the maximum number of people will understand you.

On the other hand, it's also nice to feel that historical connection with people in our past that decided to embrace rationality as a value.

These "apologies" are not gibberish. Measurements units are like words in that they are conventions that enough people agree with to make them useful as a way of communicating. Measurement units exist to help us quantify our world and if two systems do this equally well then there is no recompelling reason to switch.

Besides which, what problem would be solved in the process? People will use whatever units they prefer anyways at the end of the day. As a negative, forcing top-down change would irritate people.

> Measurement units exist to help us quantify our world and if two systems do this equally well then there is no recompelling reason to switch.

The world is already nine-tens of the way through the switch. This is a compelling reason to finish the job.

"Familiar" is a bit off target because it implies that use is a matter of individual choice.

The system is embedded in standards, such as SAE. It is embedded in industries such as construction. It is embedded into statutes, regulations, and deeds for real property.

Yes, the system is familiar, but wiping the slate clean and starting anew is not a feature of stable democracies.

> (The Imperial system) is embedded in industries such as construction. It is embedded into statutes, regulations, and deeds for real property.

So is the metric system now in most of the world.

And where the non-metric world has to interact with the rest of us, metric is embedded in their processes too. E.g. science done in the U.S. and engineering goods made for export in the US. This comment http://news.ycombinator.com/item?id=4996646 discusses some of the same issues.

The system is embedded in standards, such as SAE. It is embedded in industries such as construction. It is embedded into statutes, regulations, and deeds for real property.

I knew a civil engineer who first worked in the private industry and later got a job at the DOT.

At the construction company, they did everything in metric internally. Once a design was finalized, they would convert everything to imperial and submit to the DOT. DOT is behind the times, she thought.

When she got to the DOT, she learned their procedure. Before engineers got started reading the plans, a secretary would translate units from imperial to metric for internal use.

The fact that an old contract specifies units of rods and farthings is not an argument for anything other than defining official conversion factors between the old way and the new way.

Yes, the system is familiar, but wiping the slate clean and starting anew is not a feature of stable democracies.

What about those that already went through the metric conversion?

Why can't the existing code be modified by simply replacing old units with metric ones denoting the same quantity? If necessary, use a high level of precision in the expressions, and over time, have an initiative to slowly and gradually normalize those quantities to simpler numbers.

I was raised metric, but still find utility in the imperial system under some circumstances. I use my anatomy to measure things all the time while out on the farm, for instance. You could say step off 914cms, but I think 30 feet makes more sense in the context since you are literally counting your steps.

If you have precise measuring tools at your disposal, then I'm inclined to agree though.

How about 10 meters?

This doesn't make any sense. 1ft is ~30cm. Just measure in units of 30cm. Doing the math in your head is trivial.

But why needlessly introduce the math, no matter how trivial it may actually be?

We are constantly needlessly introducing math across all of our industries that have international partners by keeping our current system. Your point to which I was responding was that you feel it is more natural to measure in units of feet. I was pointing out to you that you can make the same measurement in a convenient unit in the metric system. We can have ease of use in both cases with the metric system.

But it doesn't matter anyway. You could sit and invent an infinite number of cases when using the imperial system "feels" easier. None of these invalidate the conveniences of the metric system, nor do they remove the compelling motivation to setup our system in line with that of the rest of the world to stop the waste of money, material, and time the is now spent on conversion, dual labeling, and confusion.

Communicating the number of steps to, say, position your tractor in the field is a long way from having international partners and dual labelling. It is still not clear to me why one would introduce the metric system into the specific case when the simplest form, the length of your foot, will do perfectly.

My foot is not one foot long, so your customary measure and mine don't match. One of us will need to convert, and we'll need a conversion table for each person.

Unless all of the people you deal with have nearly the same foot size, it's easier to deal with a single reference measure. But hey, if you and your mates want to say that the tractor is 30 feet, 20 cubits, 10 yards, 5 fathoms, or 1.8 rods away, then more power to you.

That's a good question, and one that arguably appears more often when using Imperial/Standard.

One meter is approximately one large step for a grown man.

Bonus: there are on average 20 centimeters between the thumb and the little finger of a fully stretched hand.

I disagree. A meter is a reasonable approximation of most adults's step length, but a foot is not.

Everyone who works on my farm has a foot that is approximately 30cms, so it works great. If we all had 15cm feet, then we'd say you need to step off 60 feet in the aforementioned example. It is not strictly bound by the imperial system, it just so happens that the imperial system maps fairly well to what is practical in the field without any tools, so it is what we reference. I see no benefit to introducing the metric system here, despite using it in all other areas of life.

I think GP meant you wrote "step" but you are talking about "foot". Namely, you can count 90m putting your feet in front of each other 30 times.

If instead of putting your feet in front of each othr you actually take a step you should get closer to 1m.

(most people I met measure distances with 1m = 1step when playing european football, for example and you have to be at X meters from the ball por something)

A metric user would measure the same distance to "approximately 9 meters" by taking 9 large steps. This is a very common informal method of measuring distances.

It seems more practical (and certainly faster) than to measure the distance to "approximately 30 feet" by putting one foot just in front of the other 30 times.

A small anecdote. My father was very accurate and fast to measure distance in meters using his steps. Very useful in construction. You would not use centimeters in this use case.

I didn't think there were people that really tried to defend the imperial system on anything but familiarity. not very happy of having been proved wrong.

From what I've experienced, we use the imperial units for the same reason we use degrees over radians: the units allow for common use of integer multiples of simple fractions. For some people, a simple fraction of a relatable unit really is easier to deal with than a base ten decimal, and a lot of labor out there simply doesn't need higher precision.

Of course, once you enter any sort of engineering work, well, simple fractions often won't cut it and it's far, far easier to simply use a decimal number. And then there's no reason not to use metric measurements.

> the units allow for common use of integer multiples of simple fractions.

What does that mean? Isn't "use of multiples of fractions" a property of numbers in general?

> For some people, a simple fraction of a relatable unit really is easier to deal with than a base ten decimal

What's easier is what you're used to. That's the whole point.

12 can be evenly divided into thirds and quarters, but 10 cannot. It is more likely that something will need to be divided 2 or 3 ways than 5 ways.

True, yet most of the rest of the world seem to be suffering any from this 'deficiency'.

10 can be divided in third and quarter fine. It does 10/3 and 10/4=2.5. Well, 10/3 isn't round so people don't like it but neither is 1/3 of an inch. It's not because a lot of operations suddenly become doable with numbers that you magically lose the usage of fractions.

First of all, I think it's a poor example. A full circle in degrees is an integer while in radians it's not even a fractional number (it's an irrational number)!

Also, I don't get the thing about fractions. Decimal numbers are fractions as well.

But, but - thumbs! Elbows! Feet!

Reasonably scaled measurements are very useful, though. Everything in astronomy is measured in scaled units. Mass is in solar masses, interstellar distances are in parsecs (well kiloparsecs) or light years, planetary orbits are in astronomical units. Similar, a lot of atomic physics uses angstroms.

Of course, that doesn't apply much when the difference is only a factor of 2, like the pound/kilogram difference, but even there people cheat a bit by just saying "kilo."

Before we start in... let's remember that in most contexts, the units don't matter. What matters is picking a system and sticking to it.

(and that there still is no such thing as a "one size fits all" system of units)

> the units don't matter. What matters is picking a system and sticking to it

That is exactly the problem with the imperial system. You have multiple units for the same thing, and when they are multiples of each other, it is in base 12.

You could settle on feet and have kilofeet and millifeet, and you'd have a sensible system (apart from being incompatible with the rest of the world).

It's easy to get dismissive about having multiple units, until you run into the contexts where they really are useful. Following up the example in one of my other comments: adopt the meter and the kilometer, or the foot and the kilofoot, and it won't matter to navigators, because they'll still use the nautical mile unless you literally put a gun to their heads, and if you do put a gun to their heads they'll show you why it's a much more practical unit for what they do.

>they'll show you why it's a much more practical unit for what they do.

Why? Why is it more practical? How is it better other than being more familiar? It blows me away that people can make the argument as it being "better".

One nautical mile is very nearly the length of one minute of arc at the earth's surface.

Wouldn't that make the arc-minute the practical unit?

> Wouldn't that make the arc-minute the practical unit?

Yes. However, the earth is not a perfect sphere. The nautical mile is an average arc-minute.

And the kilometer is an average centigrad.

Thanks for triggering a rarely used synapse.

http://en.wikipedia.org/wiki/Grad_(angle)

For what I know the nautical mile change due to your position in the Earth...

Why does it matter if people are using "one nautical mile" or "1852 metres"?

(http://metricviews.org.uk/2010/01/why-do-nautical-miles-ling...)

> That is exactly the problem with the imperial system. You have multiple units for the same thing, and when they are multiples of each other, it is in base 12.

That's when you're lucky, can also be 3 (yard to feet), 22 (chain to yard), 10 (furlong to chain), 8 (miles to furlong, and that's why a mile is 5280 feet), 5 (gill to fluid ounce), 4 (acres to rod, gallons to quarts), 14 (stones to pounds) and probably everything in-between.

Imagine if we measured time using units of varying multiples. Every time a friend tells me "see you in two weeks", I'm like really? 2 times 7 times 24 times 60? Fucking asshole, do I look like a calculator?

Were time conversions as common or necessary as other unit conversions, you can bet your ass decimal time would have more takers.

Even so, varying units does restrict how we can express time. Even if someone tells you something as simple as "half a week", you have to ask for clarification. And while "a week from now" translates to a date, forget about "a month from now." That could mean half a dozen different things.

A 60 minute hour is more evenly divisible than a 100 or 10 minute hour.

Does anybody use "hour" in anything other that whole multiples, halfs, and quarters? This divisiblity of 60 seems nothing more than a curiosity; minutes are used for everything else, even 3/4ths ("forty five minutes").

When someone tells me "half a kilometer" assuming they really mean 500m would usually be a dreadful mistake. It means "some uncertain distance you can probably walk". Decimal units don't magically make people more accurate.

When someone says "half a quart" who the fuck knows how much that is? I sure don't, and I'm American. Hell, even a regular quart throws me, all I have there is a vague notion that milk is sold in that amount. When someone says "half a liter" you can be sure they mean 500ml, and you can instantly know how much that is in any kitchen measuring device you have.

Half a quart = one cup.

Cool, now what is a third of a quart?

Suppose I am recounting a dish I made to someone over the phone in two realities, one with Imperial and the other with metric.

Imperial universe: "Okay, now add... say... a third of a gallon of milk" "...third of a gallon.. eehh.. half a pint of milk.

Metric universe: "Okay, now add... say... 2/3rds of a liter." "Two thirds of a liter... 666 ml it is then."

In the imperial universe poor conversations force two inaccurate estimations. In the metric universe only one of the parties is being dreadfully inaccurate.

Imperial is defined in terms of metric units, so it is possible to be as accurate in imperial. The difference between imperial and metric is that imperial adds mental overhead that in practice reduces accuracy.

One third quart = 2/3 cup. I have a 2/3 measuring cup in my kitchen.

I've never heard anyone say a third gallon, but just convert to ounces. 128 / 3 = 48. That's 3 pints, btw.

Of all the "math is hard" arguments, I think the kitchen measures are the least convincing. Everything is a power of two. You can halve or double a recipe without even thinking.

All of these conversations, even with special cases already marked on kitchen equipment, are all more complicated than the stupidly simple equivalents. Why in the world would you choose imperial over metric, unless you are just an old curmudgeon?

You can think the arguments for metric are weak (most of the world disagrees...), but the arguments against it are nonexistent.

(Dividing by two is just easy in a decimal numbering system as it is in a hybridized decimal system, so give me a break)

The cost of switching is non zero. I'm not bothered by metric, I can deal with it just fine. I'm just not bothered by standard units. I would never propose switching to standard from metric, but I just don't see what all the fuss is about.

Switching would be done in a lazy manner. I can't see how the cost would be prohibitive, plenty of other countries have managed it so surely America can too.

128 / 3 = 48

Come again? This doesn't quite look like sarcasm, or did you want to prove the OP's point?

Or maybe this is just an explanation for the taste of British food...

oops, I think I should slink away quietly now...

Half a quart = two cups.

Haha, fuck. I consistently read that as pint.

Incidentally, there was a metric calendar, invented alongside the metric system: http://en.wikipedia.org/wiki/French_Republican_Calendar

It never gained much hold, probably for two reasons

- its units were too far off the customary units, hard to convert, and didn't fit into the neat 10^3 system. The other units (metres, kilograms) were close or easily convertible into what they replaced (ell and pound, both at approximately 0.5 metres/kilograms).

- the number of days in a year is set, so you never end up at a neatly decimal system with e.g. 10^3 days in a year (and even worse, it's a weird fraction leading to leap years and seconds)

> the neat 10^3 system

> a neatly decimal system with e.g. 10^3

Why is ^3 neat? 10 for the radix is standard all over the world now, except perhaps in IT where there's some competition from 16.

But 3 for digit groups isn't very standard. East Asia uses groups of 4, so 10,000 and 100 million are standard. India uses lakh and crore, i.e. the oddball groupings 3, 5, 7, etc.

For time, you need a system that let you easily express the year cycle, since the the climate affects a lot of things from economy to sports.

We need to be able to easily count days, since we sleep at night. (It would be very difficult to change to, say, a 20 hour cycle.)

We could skip the month, week, hour, minute and second, but the year and day are essential.

You think there are no advantages to easy divisibility?

16 is divisible by 1, 2, 4, 8, and 16.

24 is divisible by 1, 2, 3, 4, 6, 8, 12, 24

10 just has 1, 2, 5, 10

So what if the old units are easily divisible? If you have 1024 g of something, you can divide that by 2 ten times.

That's an argument against counting in base 10, and it's a fair one. However, while we do count in base 10, metric is the way forward.

If you wanted, you could always count in 2 times, 12 times or 16 times the basic SI units.

And then people invented decimals.

It's frustrating that the same people who push weird systems (ounces, the old money in UK) instead of metric units and decimal money are comfortable doing all kinds of mental arithmetic, but freeze when as soon as you involve a decimal point.

People who have no trouble with the concept of "half of a third for four people taken out of this bag of potatoes" get stuck on "0.25".

For all the people who answered my post - I agree that metric and SI are the sensible way forward. I'm kind of relieved that some sections of US[1] industry are choosing to ignore the international market or to lumber themselves with extra costs for both systems.

[1] Because I'm not in the US; I'm European and I want our industry to do well.

Converting between m and km is dead simple, it's just a "decimal shift" / textual operation (move the comma).

We have 10 fingers and that's probably why base10 is somewhat naturally wired into our brains. I'd like to remove 2 fingers and go to base8 but can't quite settle on the right ones.

Thumb is out of the question because it's what sets us apart, lets us use tools and so forth. Next finger up is usefull for pointing, not getting interrupted while on the phone and most importantly pulling triggers...seems valuable enough. Finger #3 has too much social importance due to it's use as a universal sign of diagreement. Finger #4 seems to be of mostly sentimental value if you're married I could see this one as a viable candidate. Finger #5 is freakishly small compared to the rest but it is also very valuable for swearing.

So I think I'd propose removing both fingers #4 on birth from here on out or I suppose we could keep it as is. Occam's razor would suggest keeping it as is but could also be used to cut off the fingers.

Too many choices...which makes me wonder if binary isn't the way to go after all.

I'm not sure that base 10 is wired into our brains. It's probably the case that we're just used to base 10. The reason why it's can be so hard to read numbers in base 8 or some other base out loud is that you have to convert it to base 10 to say it because we use . . . base 10. (Though you can get around this by reading the numbers as though they were in written base 10---I had a professor who did this with hexadecimal.)

The argument goes the other way: there will always be numbers that do not divide your base. We can not get around that. Thus if we want to reduce the number of special cases, instead of going for high divisibility, we should go for the lowest divisibility.

I recommend base 11, since it's the closest prime base to the customary base 10.

Instead of a measurement like 7/16 inches, we'd use something like say 11.1 millimetres (or a little more than a centimetre in everyday use)...

Maybe it's just that I'm so used to decimal measurements, but whenever I see plans that use fractions of inches, it looks confusing and imprecise... Coming from a decimal background, I don't really feel like using a fraction is ever better than using a smaller unit unless you're making an estimate (ie, "about half a kilometre").

It's not really "standard junk" though. Imperial measures are standardized human units. I have a foot that is about a foot, a knuckle that is about an inch, a stride that is about a yard. One day carrying a gallon of water a decent distance I realized that this was about the max amount the average person could carry comfortably over distance.

That is what kills me about the metric system. It seems to intentionally ignore the human scale. Why is 10 centimeters not a standard unit of measurement, and this is the important part, that is marked on every ruler and tape measure? The same for 10 Milliliters, 10 grams and 100 grams. Over the entire metric system the base 10 increments that are human scale are always ignored. The liter is the only one that comes close. Why is this?

Until the human scale is taken in to account I'm perfectly happy using more than one measurement system...

> Imperial measures are standardized human units

As someone raised metric, Imperial measures are just weird, pointless and baroque. It is nothing more than a question of what you are used to.

I moved from Belgium to the US last year, and one of the things that surprised me was that metric measures actually see a fair amount of use in the States. It makes a convoluted system even more weird, but it's also just plain fascinating.

2L bottles of coke and 9mm bullets, miles except when people suddenly switch to kilometers, 50 meter pools and 5K jogging runs but a 120 yard football field, 2 oz shaving cream but eye drops come in a 20ml bottle and so on.

Guess that's what globalization does for ya.

I'm an American that grew up during the time they "tried" to go metric and none of this surprises me. Volumes are tricky for me, but I have no problem going from imperial to metric. Most other countries see the US and are like, "why aren't you using metric?" and we're like, "what's in it for us?" We learned metric in school and it's great, for exact measurements. Sometimes you just want to use what you have and not think about it. I don't know what 310mL is, I know how to measure 2 cups of water with...2 cups of water.

Speaking of globalization, TVs are still sold and classified in inches :-)

TV's in inches? Maybe but at best you are half right. http://www.buytvsonline.com.au/products/?filter=25

> I don't know what 310mL is, I know how to measure 2 cups of water with...2 cups of water.

Do your cups come only in one size? (And aren't the bigger coffee mugs standardized to 200ml?)

"Speaking of globalization, TVs are still sold and classified in inches :-)"

Nope...

Samsung UE75ES9000S - 75 inches Samsung UE65ES8000Z - 65 inches Samsung UE32D6200W - 32 inches LG 55LM960V - 55 inches LG 47LM960V - 46 inches

Notice a pattern, yet?

No? You're assuming things that aren't true in a lot of countries.

To be fair, non-metric units are also use worldwide in some specific fields. In aeronautics, height is in feet. In a boat, distance are nautic miles (not even the same miles as Americans on the road).

Quick quiz: what's the diagonal size of your laptop screen in centimeters? Your mobile phone?

So it doesn't matter if you use completely unrelated metrics for different things. When you want to buy a laptop you know how many inches you want. When you swim, you know what a 50 meters pool means. But do you care how many laptop diagonals you're swimming? Probably not.

Now back to US switching to metrics: I think the real argument in favor of sticking to imperial is the cost and risk of the switch. Risk because confusion between metrics could lead to a catastrophe (example: filling the tank of a plane with liters when it should be the same number of gallons).

You understand, though, that the reason laptop screens are measured this way is because of America's continued use of the imperial system.

Yes, TV screens are measured in cms, no reason why computer screens couldn't be too.

Nautical miles are used in aviation as well. In both cases, the use actually has a very good, albeit obsolete, reason: one nautical mile is equal to one arc minute of latitude on the Earth, to within reasonable accuracy. Very handy for navigation, at least when you didn't have a magic black box to do it for you.

I previously had a flight computer with two displays, each of which showed the distance to the next waypoint. One showed the distance in nautical miles, the other in statute. I could never remember which was which, and always had to look at both and see which number was bigger.

Silly measuring systems. We should measure everything in planck units.

Personally, I think the cost argument goes in the other direction. It's true that there would be costs to switching, even potentially lives lost. But there are constant, ongoing costs to having mixed units, potentially including lives lost (and certainly very expensive space probes lost). To me, that says that we should switch as quickly as possible to stop that ongoing cost. It may cost more up-front, but the cost of switching eventually ends, while the cost of staying as we are never stops.

> But there are constant, ongoing costs to having mixed units, potentially including lives lost (and certainly very expensive space probes lost).

In engineering there is never an excuse for not knowing the units of measure of a value in use. That probe would have been brought down just as easily by mistaking a 'kg' parameter as 'g' as it would have been by mistaking a 'kg' parameter as 'lbs'.

What's worse, in engineering there are multiple metric standards of measure (c-g-s, m-k-s, subatomic measures, etc.) There's no way around it, you have to know your units.

Excuses don't matter. The fact is that these mixups happen. And the probe would not have been brought down just as easily by mistaking 'kg' for 'g', because that would result in a number that was off by a factor of a thousand, and the result would be unlikely to make any sense. The meters/feet mixup that actually did happen could only happen because being off by a factor of 3.3 resulted in a number that still made basic sense, even though it was incorrect.

There are documented instances of metric/imperial mixups crashing space probes and forcing airliners to land after running out of fuel in midair and such things. Are there any documented instances of similar metric/metric mixups?

> There are documented instances of metric/imperial mixups crashing space probes and forcing airliners to land after running out of fuel in midair and such things.

As I recall, the Gimli glider came about because they were trying to switch to include metric units and had to change their procedure to do it, but didn't make the change in all places where it was necessary. This resulted in pilots using an Imperial conversion factor to try to calculate a metric fuel loadout, with disastrous results. http://en.wikipedia.org/wiki/Gimli_Glider#Refueling

... this isn't exactly selling me on the idea that switching up all the units used in the U.S. is actually a good idea.

This sort of error can happen any time you have mixed units, though, and as long as some countries insist on not using metric, the potential is there. The potential goes away once you switch, so as long as the costs for switching and for staying mixed are both finite and non-zero, it makes sense to switch now and get it over with.

I wonder if the Gimli glider incident had anything to do with imperial units being the preferred unit in the US. In any case I think the aviation industry would be well across this issue by now, given they would have to deal with conversion all the time on international flights between the US and metric countries. There is the benefit of hindsight with the Gimli incident, so the same mistakes need not be repeated.

Automobile tires are an interesting case of measurement system compromise - the mounting diameter is measured in inches, but the section width is measured in millimeters. Sidewall height is even stranger - it's represented as a percentage of the section width.

Example: 195/60R15 - 15" diameter, 195 mm wide, and 117 mm sidewalls (60% of 195)

To my understanding, diameters are almost always measured in inches, even in countries that follow the metric system.

> In aeronautics, height is in feet.

Note that this is only because of US influence. USSR and its satellites used meters-graduated altimeters, and so did most of the rest of the world until the end of WWII at least.

Screen sizes are actually always in mm height and width. The diagonal size is just an approximate size.

My experience has been that the US and Canada are still "mixed" enough that it's highly noticeable. And I hear it's similar in the UK. The main differences are absence of an official government position (UK and Canada both have that, but with exceptions and/or significant numbers of people just ignoring it), and we still use Fahrenheit for temperature (amusing since the degree Celsius is arguably less "metric" and more just SI).

Otherwise, it seems a largely arbitrary toss-up as to what will be metric in any of the three countries and what won't.

At my last job, we measured product thickness in mm; area in square feet; throughput in meters per minute; coating thickness in nm, angstroms, or fraction multiples of 550nm; weight in tons (imperial) but some input materials in grams and kilograms; and pressure in hPa, atmospheres, psi, and torr (occasionally in the same sentence and graphed logarithmically in some cases).

Basically, we use units like any tool. Use whatever tick marks line up to the problem conveniently. You can always covert later if you need to.

Only vaguely relevant, but I grew up in a rural area in Canada which caused me to learn a strange set of units. For me, highway distances are measured in kilometres, but country roads are measured in miles. Groceries are priced per kilogram, but my weight is in pounds. I readily swap inches and centimetres for measuring small sizes and distances (sometimes on the same project). I am more comfortable with Celsius, but the thermostat in my parents' house was in Fahrenheit.

Just to throw an additional wrench into things, prior to official metrification (which technically predates my birth), Canada used "imperial" (i.e. British) units, not "standard" (i.e. U.S.) units. Because of this and the close proximity to the U.S., one had to be careful about just which gallon or pint you were talking about.

People younger and/or more urban than me seem to be 100% metric. I am starting to learn my weight in kilograms, but I still have no idea what my height is in cm without converting.

Canada also has so-called weak metric measurements: 454g of butter (1 lb), 354 ml of pop (12 oz) and so on.

Yes, though I think this is largely due to trade with the U.S.. It probably helps keep some standard units alive in Canada.

Indeed in country fully converted to metric, the old unit are converted to their closest sane metric equivalent.

For example, my grand-mother still talks about buying a pound of stuff. However a pound is now understood as meaning 0.5 kg, we even learn it that way in school.

I would hazard a guess that we're roughly the same age because I grew up with the same mixture of units but I think it's less to do with growing up in a rural area than the fact that your parents and grandparents were educated on imperial units and even though metric was standard by the time you were born, the imperial system was still ingrained in your elders and some of that nomenclature was passed on to you. When I talk to anyone over 50 I have to be careful to remember when they say it got to -70 a few years ago they are most likely saying it was -70F and not -70*C.

I grew up in Australia with metric, with parents and grandparents who grew up with imperial units. Though it seems things happened differently in Australia as my parents (and possibly grandparents too) converted to thinking in metric at least most of the time. That said, it's still reasonably common to hear people quoting their personal height in feet and inches. Even then, most people born post-metrification don't really have a grasp of imperial units (the exception tends to be people who have spent time in the US).

Person heights and baby weights are the only things I ever hear in imperial in Australia, end even then only half the time.

This appears to be the situation in the UK, too.

In my neck of the Canadian woods, the default unit of measurement for road distances was the time it took to travel that distance.

"How far is it into town? Oh, about twenty minutes."

People could deal with kilometers just fine, but you'd have to ask for them explicitly. Often they'd give you a rough guess by converting from minutes, and that's how you could back your way into the unofficial local speed limit (as opposed to what the signs said).

At first I assumed this was universal, or at least universal to rural areas, but they don't seem to do it much down here in Texas.

At the risk of being lumped in with the negative/unhelpful/HN-is-on-the-decline comment crowd, and I hate naysaying here but...

Seriously?

1) If you haven't seen enough of these White House Polls go by yet (and there is a never ending list of inanity, for example: http://www.modernman.com/12-dumbest-whitehouse-petitions/) let me clue you in. They do nothing. Nothing. No one reads them. Just go back to wishing on a star.

2) The belief that something like this would ever be on the White House's radar/todo list is honestly just retarded.

3) Why is this even here? This isn't Reddit. The focus of HN is pretty nebulous these days but this is well outside the realm of entrepreneurship and programming which I believe has always sort of been at the heart of HN.

4) Rabble rabble HN is in decline.

It does have a lot to do with programming actually. I'm building an international application and I have to convert all my dimensions and weights to make it work in the US.

It gets even more awkward when it’s not just output: we’ve got a refine-by-height range slider in our system that I’m having to localise.

No. It has as much to do with programming as currency conversion does. It's a problem involving numbers that people occasionally solve with the use of code. By your logic beanie babies have a lot to do with programming because someone built a site to list and sell them online (ebay).

But hey, the metric system seems more sensible to me too.

Edit I don't mean to come off as a jerk. I haven't slept yet and just got a BS call from m boss so I'll probably read this later and wish I were more diplomatic.

Everytime I try to use data that comes from public US sources, it's a PITA to deal with Imperial Units. It does have an impact on programmers/developers/engineers/etc.

Just reading news about weather or some climatic phenomenon, all in Fahrenheit. Wth, Fahrenheit.

"President Andrew Jackson in the main foyer of his White House had a big block of cheese. The block of cheese was huge — over two tons — and it was there for any and all who might be hungry. Jackson wanted the White House to belong to the people, so from time to time, he opened his doors to those who wished an audience.

It is in the spirit of Andrew Jackson that I, from time to time, ask senior staff to have face-to-face meetings with those people representing organizations who have a difficult time getting our attention. I know the more jaded among you see this as something rather beneath you. But I assure you that listening to the voices of passionate Americans is beneath no one, and surely not the people's servants."

"The best argument against democracy is a five-minute conversation with the average voter." - Churchill

There's a couple of things you'd want to consider converting to metric: long distances, short distances/dimensions, volumes, weights, and temperature come to mind.

Long distances: swap out a bunch of highway signs, consider that 60mph (a mile a minute) ~= 100km/h, not too hard on people but a lot of signage needs to change. Feasible.

Volumes: people are used enough to 2-liter bottles of soda, expect the 3.78 liter milk to stay around for a while because of supply chains. Gas prices will be modestly interesting for people, but really easy on the industry.

Short distances/dimensions: now things get tricky and potentially expensive. There are a lot of fractional-dimensioned parts out there in industry in different supply chains.

Weights: 2.2lb = 1kg and you're pretty good. Nobody really uses ounces anyway!

Temperature: Here's the thing about temperature: converting would be relatively useless because Real People don't do math with the temperature outside. Even scientists don't do math with the temperature outside all that much. For most people, a scale that starts at 0="civilization shuts down because you can't ice the roads" and goes up to 100="heatstroke territory" is a fine representation of humanity's day to day temperature. Why would we bother changing it?

> For most people, a scale that starts at 0="civilization shuts down because you can't ice the roads" and goes up to 100="heatstroke territory" is a fine representation of humanity's day to day temperature. Why would we bother changing it?

I thought you were talking about Celsius at first...

Mecanical parts are the most difficult thing to switch because there are many things defined in relation to one another. For example the american UNC threads have different angles than the metric ones do and therefore it is impossible to replace one with another. For this reason alone it will take very long time to do a full switch from one unit system to another. However, many "metric" units are actually slightly adapted imperial ones. For instance you can get a lot of 25 mm stuff in Europe that is almost equivalent to the 1 inch stuff you get in the US (1 inch = 25.4 mm) and similarly there is a lot of 30 cm and 60 cm stuff in stead of 1 foot and 2 feet stuff.

>not too hard on people but a lot of signage needs to change. Feasible.

Very expensive though. Signs normally have a 20 years expected lifetime. Now you need to replace them all at once. Plus a lot of the sign locations need to be changed, unless you want all those "Exit 29 1 mile" signs to now say "Exit 29 1.6 km".

You do not need to replace them all at once. For example the new signs could be European style, red ringed white circles with the number inside. Virtually every car has both readings already. This would make new speed limit signs immediately recognizable to more visitors in the future while avoiding ambiguity of units during the transition. They could even say km/h during the first generation.

Road signs need to be very clear and instantly understandable. Adding a tiny delay to comprehension; a tiny bit of lack of attention to the road; could, when multiplied over the number of kilometres driven and number of drivers and time mean many deaths.

Whether that's acceptable or not is another matter, but it'd suck if "km/h KILLED MY FATHER" became a meme.

It is odd how some countries make massive national changes overnight. eg, Sweden:

(http://users.telenet.be/worldstandards/driving%20on%20the%20...)

> In 1955, the Swedish government held a referendum on the introduction of right-hand driving. Although no less than 82.9% voted “no” to the plebiscite, the Swedish parliament passed a law on the conversion to right-hand driving in 1963. Finally, the change took place on Sunday, the 3rd of September 1967, at 5 o’clock in the morning.

Leaving it until now has meant the UK would find it very hard to change.

Why not phase things in, by having both measurements put on, for all new signs?

Exit 14 - 1 Kilometer (.6Miles)

Then, as the old signs wear out, eventually all signs are replaced.

Rounding to the likes of 1.5km is good enough for a highway sign.

The devil is in the details.

In the US, all speed limits are in 5 mph increments.

So, let's say you convert your 60mph limit to 100kph (Really 96.5). 70mph is 112.65kph. Do you round down to 110, or up to 115 or 120?

If you round down, congratulations, you just cut the speed difference between a rural highway and interstate essentially in half, as a "true" 17kph difference is only 10.

Anyone in a country that uses the celsius scale knows that the temperature argument is rubbish... It's totally and completely what you're used to. I doubt people really think of temperature in more than about eight or ten increments anyway (bloody freezing, cold, pleasant, etc.) so having a range of forty or fifty integers really gives you more than enough precision.

I suppose it doesn't really matter what people use to express the temperature in common use, but having a unified scale across ambient temperature, cooking, science (1K = 1°C), manufacturing, etc. that people in almost every other country uses really does make sense, especially when the conversion is so annoying.

My point is more "why should people have to change what they're used to for a small subset of the scientific class?" - of all the things that people do math with, and would benefit from decimalization and metrifying, temperature is pretty much the last.

Sad it only has 237 votes as of my visit (waiting for my acct to validate so I can sign).

The problem is, I think the US has already declared itself to be metric to little effect.

http://en.wikipedia.org/wiki/Metric_Conversion_Act

It's not the do-nothing congress this time, it's the learn-nothing public.

Just a simple measure like forcing all government signs to use metric would go a long way.

It's nice to be reminded that there will always be fresh waves of not-yet-cynical people to take up issues like this. But boy, am I cynical about the chances on this one.

The wikipedia article on Metrication in the US [1] isn't the best article ever but is worth reading for mentions of previous efforts.

A few things: - the US Congress has in various ways 'blessed' the metric system, more than any other. However...

> Proponents of the metric system in the U.S. often claim that "the United States, Liberia, and Burma (or Myanmar) are the only countries that have not adopted the metric system." This statement is not correct with respect to the U.S., and probably it isn't correct with respect to Liberia and Burma, either. The U.S. adopted the metric system in 1866. What the U.S. has failed to do is to restrict or prohibit the use of traditional units in areas touching the ordinary citizen [2]

Did you know that Jefferson proposed a decimal system for the US before the SI system had come about? (See e.g. [2].) There were also proposals to measure land in decimal units rather than in 640-acre sections.

[1] http://en.wikipedia.org/wiki/Metrication_in_the_United_State...

[2] http://www.unc.edu/~rowlett/units/usmetric.html

I was born in Russia and used the metric system until i moved to the US. Imperial system is so archaic it's amusing to see a developed nation use it. A few centuries ago Russians used to measure weight in "handfuls" and short distances in "elbows." (scratch that, it's "cubits") When only a fraction of the population had any sort of education, it was easier for everyone to understand an anatomical measurement. Eh, some things never go away. I don't anticipate US dropping this... ever.

Sadly, we (US Citizens) all learn the Metric system starting in at least 7th grade (was for me at least back 15 some years ago). We continue to use it through High School for courses such as Chemistry and Physics as well as University studies.

However, many of those that are not interested in going into a Science field tend to discount the Metric System in the United States as nothing more than a "means to an end" in order to get a passing grade. They quickly forget it or just pay lip service to it as they don't see the need for it outside of the classroom.

Until that changes with some sort of mandate by the US Government, I'm afraid as you mentioned, the larger percentage of the United States will feel no need to care about the Metric System outside of a few Science courses they took back in school.

You're absolutely right. Technical people would most likely embrace the switch. Everyone else will brush it off. I find that Americans are typically very cautious of any kind of change. Especially baby boomers. Let alone a change that is "imposed" by the rest of the world. That isn't going to fly here. We don't do things in the same way the rest of the world does them. That's just our mentality. Imagine a football field marked with metric units. Man, I just cringed a little bit. :)

> [...] and short distances in "elbows."

Cubit might be the word you were looking for.

Ah, Yes! Sorry, that translation was literal :)

That's what I was suspecting. It's similar in German. (My Russian is a bit rusty.)

The way I explain this one to my European friends is:

Do you remember the transition to the Euro? How you had to mentally convert prices at first? And how old people had more difficulties with it in some cases? Now, imagine that, not just for one unit, but weights, lengths, temperatures and volumes, all at the same time.

Well, you don't have to be so drastic. Just teaching metrics in all schools and requiring their use in higher education would be enough for the next decade or two. Only then you can start thinking about something as the petition asks.

Teaching it academically is different from 'living' it. See my other answer above/below:

http://news.ycombinator.com/item?id=4996402

Metric is taught and used in school (middle, high, university) in the US for any sort of math or science, leastways anywhere I’ve ever been… If I were using any kind of tools to measure things and make calculations, I’d use metric, but in daily life, viz. in speech, it’s easier for me to just use the familiar imperial—especially if I want to make myself easily understood to normal people.

quite frankly this is deceitful, a lot of Americans already use the International System daily for their work, and I would bet that a very large number of Americans have some knowledge of it. Whereas the Euro was completely new, the International units have been here for years.

> deceitful

I'm telling it like I see it, please do not ascribe malice to what I'm writing. I wish we had the metric system in the US, but the units just aren't as meaningful as familiar degrees F, pounds, inches, feet, miles, and so on. That's true for me even after having spent a lot of time living here in Italy, to varying degrees, depending on how much I use a given unit.

sorry I wasn't implying any malice, just wanted to say your explanation was misleading in my opinion

Everyone managed after around 2 years, with the Euro. Even older people.

But that's just one unit. Try doing it with 4, and it gives people an idea of the difficulty involved. I'm not saying it's impossible, just hard.

Are the US afraid of a little challenge?

I can't speak for most people, since I'd be happy to change, but my guess is their thinking is along the lines of "it ain't broke, so why should we fix it?". For most 'everyday' use, the defects of the imperial system are most likely not that visible: if I have to guess how far something is in miles, it doesn't matter much if I say 2.5 miles or 4 kilometers, since I'm basically sticking to one unit and fractions thereof. Where the metric system starts getting a lot nicer is if you have to be more precise and mix and match units, or deal with multiples. In other words, estimating my height at 5'10" is fine for most people, but "how many davidw's would it take to cover a football field" is a problem much easier solved with the metric system.

Does that make sense?

It sure does. And I understand the issue that lies therein.

But, if the rest of the world is to ask of the US to switch to the metric system, there will be a time when the authorities have to enforce the system onto the citizen.

Sometimes, the greater good of the community does not align with that of the citizen. We Europeans have switched from our country's respective currency to the Euro not to please us personally but for the economic good of the whole European Union. (Whether it has succeeded or not is another debate altogether.) It sure wasn't easy for the ol' timers, but now it's all behind and even my parents don't think back in Francs when they have to pay their baguette and wine.

> We Europeans have switched from our country's respective currency to the Euro not to please us personally but for the economic good of the whole European Union.

The behind-the-scenes motivation wasn't about the common good, it was about the French trying to gain formal influence on monetary policy. The Germans had to agree in exchange for the French consent to German reunification. (Before the Euro, the rest of Europe was more or less reduced to copying German monetary policy, or face devaluations.)

They (I'm swiss, so I wasn't affected that much by the transition) had a double display (prices in french francs/ deutschmark / lira) for quite some time before and after the introduction of the actual currency (coins and banknotes). It's not a perfect solution, of course, but the point is that the transition wasn't abrupt.

This doesn't explain anything. Why is the USA the exception?

Because we're exceptional! :-)

No really, the worst thing that ever happened to metric system conversion was getting endorsed by the UN. That was the kiss of death. We created the UN, we host the UN, we fund the UN, and we hate the UN. Anything backed by the UN gets turned into the UN trying to take over the US and creating a new world order.

And after the debacle with the, UN-based, ITU trying to take over internet governance metric will never get a serious political foothold in the US.

Oh, the problem with the Euro was that they raised prices everywhere where they introduced the new currency. What was previously 0.8€ becase 1€, 28€ to 30€ and so on. Economic power also moved from individual countries to the ECB in Brussels. If the US started using SI (Systeme International), it's not like you would be subject to a metric-controlling organisation in Paris. :)

The ECB is in Frankfurt, Germany.

Actually, they didn't raise the prices on average. (There were even some papers about it. And not too much actual power shifted to the ECB in Frankfurt, since the other European countries were reduced to copying German monetary policy (or face humiliating devaluation) long before.

That's ACTUALLY where Le gran K is still stored. (outside paris)

It's the last artifact of a physical object used to measure all others. And that fucker changes weight too, so the kilogram ISNT stable. Its just like all those nasty imperial measurements used to be.

The UK managed the switch from imperial to metric okay. It's really not that hard.

http://en.wikipedia.org/wiki/Metrication#United_Kingdom

Would indicate that the process has being going on for some 40 years and is still not at all complete. That to me indicates that it's not "easy" either.

Then look at one of the many other countries that have completed it: http://en.wikipedia.org/wiki/Metrication#Chronology_and_stat...

Mostly okay. Our roads are still in miles per hour, and we still sell a "pint."

But at least food labels are all metric.

They still haven't converted. Miles & Miles per hour are still used for driving.

When do you even deal with these things on a day-to-day basis? These days most people buy prepackaged stuff from the supermarket. I don't think many people go to market stalls and struggle telling the merchant how many potatoes they want. I mean, some do, but it's rare enough that they would probably figure it out quickly.

Well old people manage to move from Europe to the US (and visa versa) do they?

Just with the Euro the change should be at once. Then everybody will be fine in 2 years or so.

ISO 216 paper sizes while you're at it, please!

yes! As a US expat in europe, this never ceases to cause me trouble. Plus the A size ratios are just lovely.

Damn that would be nice, any time I see US paper sizes I go "WTH? Legal? What are you talking about?"

I'm surprised paper hasn't formed a larger part of this discussion.

The 'A' system for paper has many advantages, and actually would be something that could be accessibly changed (all printers and scanners handle it just fine).

> The 'A' system for paper has many advantages

The ISO system in general, ISO 216 and 269 provide 3 series (A, B and C, A is the base series, B is the geometric mean between two sizes of the A series, C is the geometric mean between the A and B series at a given index, and is thus mostly used for envelopes for the A series: an envelope Cn will hold an An sheet without folding, and of course a Cn envelope will fit an A(n-1) folded in two)

I look forward to everywhere using metric.

I'm in the UK, 27 and still struggle at times to comprehend lbs, ounces, stone, feet, inches, yards, miles etc., when everything I was taught in school was in metres, litres, newtons and kilogrammes.

Also in the UK.

Apart from lengths (feet vs. metres) I don't really find myself needing to calculate between the different units. I couldn't tell you how many litres in a 4 pint bottle of milk (or a pint of beer :)) but all other milk (or beer) is sold with those units, so I can easily compare.

I mean, we are supposed to be metric - but there are plenty of imperial measures in use (height, is another obvious example).

height, is another obvious example

Strangely enough, whilst I'm fine with lengths and distances in metres, the minute someone tries to tell me how tall they are in metres and centimetres, I'm completely thrown. It's the one conversion I pathetically still really struggle with (UK -> Poland in this case).

I had the very same problem, only in the opposite direction, living in Poland for the first 27 years of my life and moving to the UK just over a year ago.

Just bear in mind that 6ft is approximately 180 cm, anything above is above, and anything lower is lower. This gives you a first approximation with only remembering one number. Also, 4in is about 10cm and is easy to add/subtract both ways. This might not be very exact, but it will give you a quick idea.

One note I like to remember is that a foot is the length of a school ruler, everybody remembers the size of a school ruler.

We ask for a footlong, a quarter pounder etc when we go out for fast food.

Our fat friends are 16 stone, 17 stone.

We live miles away from each other.

Penalties in football are taken in the 18 yard box.

We use cup measures for flour, sugar etc in cooking.

The average penis is ~6 inches when fully erect.

I've got two 4 pint cartons of milk in my fridge.

I could go on. Imperial units are absolute muck and I cannot wait for a entirely metric world.

a gallon of milk, eh? you must drink a lot of it

Baby.

> We use cup measures for flour, sugar etc in cooking.

We do? My cookbooks are in metric units. In fact I own no books that use "cups."

As an example go have a look at http://gordonramsaysrecipes.com/ which hosts a collection of Ramsay's receipes. All in tablespoons, teaspoons and cups.

That's an American web-site. His books are in metric.

http://www.amazon.co.uk/Gordon-Ramsays-Ultimate-Cookery-Cour...

Click "search inside." Everything is in grams.

edit: That web-site isn't even associated with the chief. It is just some fan site. Here is a legit web-site and it is all in grams: http://www.channel4.com/4food/recipes/chefs/gordon-ramsay/go...

> Click "search inside." Everything is in grams.

There's loads of references in that book to knobs of butter and tablespoon/teaspoon measurements.

teaspoons and tablespoons are metric - one teaspoon is 5 ml; one tablespoon is 15 ml. I'm not sure how useful it is having a volumetric unit instead of a mass[1] unit; but that's one thing I like about US cooking. "About a cup of this; about to cups of that" - it's all nice and intuitive. I know roughly what 500 g of flour is, or sugar, but 80 g of butter is tricky.

[1] sorry if I'm using the wrong term. Friendly corrections welcomed.

Use http://onlineconversion.com

1 Tablespoon [UK] = 14.206 531 25 milliliter

Tablespoon and teaspoon measurements correlate to fluid ounce measurements - 1 Tablespoon [UK] = 0.5 ounce [UK, liquid]

They're definitely imperial.

> We ask for a footlong, a quarter pounder etc when we go out for fast food.

So? There's nothing wrong with asking for something called a "footlong" and getting a 30cm meal. Nothing wrong with asking for a "pint" and getting 500ml of beverage.

I don't mean that we only ask for these things, we are served these things. We are served 6 inch or foot-long subs; pints - not half litres - of beer; etc.

It's not just a simple lingual thing. We actually buy products that are divided into round imperial measurements, i.e. 1 foot, 1/4 of a pound, 2 pints, etc.

> We actually buy products that are divided into round imperial measurements ... Imperial units are absolute muck and I cannot wait for a entirely metric world.

Ah sorry, I misread your grandparent post, I thought you wanted to keep the Imperial names & sizes.

From the petitions.whitehouse.gov petition kindly submitted for comment here:

"The United States is one of the few countries left in the world who still have not converted to using the Metric System as a standardized system of measurement. Instead of going along with what the rest of the world uses, we stubbornly still adhere to using the imprecise Imperial Unit - despite the fact that practically every other country that we interact with uses Metric."

This petition has the same problem most petitions submitted to the White House have--its factual premise is incorrect. I'm an American who has lived in another country (Taiwan) for years. The National Institute of Standards and Technology reports that "The United States is now the only industrialized country in the world that does not use the metric system as its predominant system of measurement."

http://www.nist.gov/pml/wmd/metric/upload/1136a.pdf

But the same government report notes that

". . . . In 1866, Congress authorized the use of the metric system in this country and supplied each state with a set of standard metric weights and measures.

"In 1875, the United States solidified its commitment to the development of the internationally recognized metric system by becoming one of the original seventeen signatory nations to the Treaty of the Meter."

In other words, the United States has treated the Metric System as official and legal since before my great-grandfather was born. The customary measurement system is, by contrast, simply customary, not mandatory. The United States has been metric since 1866 "in the sense that Americans have been free since that time to use the metric system as much as they like."

http://www.unc.edu/~rowlett/units/usmetric.html

If a particular individual or corporation engaged in manufacturing or trade wants to use metric measurements to meet customer needs and gain a profit, no one in the United States is stopping that. If someone desires to use customary measurements out of sheer habit from long-established custom, no one is stopping that either. My late dad the industrial engineer was aware of plenty of industries in the United States that from the 1970s, at the latest, had gone fully metric simply because those industries were involved in vigorous international trade. Perhaps the best governmental nudge that can be given for more use of metric measurements in the United States is more encouragement of developing international markets for domestic businesses.

I note that customary measurements are often used in other countries even long after metric measurements are adopted officially. For example, the Republic of China (the regime that governs Taiwan at present) has been officially metric since before I was born. Japan (the former governing country in Taiwan) was metric from the 1920s. But the unit of weight for vegetables bought in an open-air market in Taiwan is still the traditional 斤 (jin "catty," or Chinese pound), although that is now standardized at 500g. Prices are given in monetary units per 斤 for most fruits and vegetables to this day in markets in Taiwan (and in China).

A Facebook friend with a scientific education recently told me about the saying "A pint's a pound, the whole world round." If the United States begins using metric-standard units more for selling foods and the like, then perhaps a half-kilogram (500g) package will be considered to be one new "pound," just as a half-liter (500ml) package will be considered to be one new "pint." It is interesting to me that traditional Chinese culture and traditional British culture both had weight units in that range, about a half kilogram even before standardization to metric units. How are grocery measurements treated in Britain these days?

But aren't things like road signs in mph defined by law?

My understanding of speed limits in the US is that each state defines it. There is no national speed limits (hence why Montana is famous for its high speed limits on motorways, but not much else).

But I doubt that Washington D.C. uses kph on its speed signs, though.

Arizona has some signs in Kilometers. [http://www.nytimes.com/2010/09/15/us/15highway.html?_r=0]

The last sign in the US that I saw marked in metric was one on northbound I-95 in South Carolina, just north of the I-26 interchange. The sign was replaced about 2 years ago with a new one that only shows distances in miles.

I suspect that metrication of the highway system in the US will only happen if a large state like California or Texas converts. But with the current budget situation, that's highly unlikely.

The federal government has a law that federal funds can not be used to pay for signs with metric measures on them.

Do you have a source for that?

http://www.legistorm.com/score_gao/show/id/25766.html

"However, Congress passed legislation in 1994 and 1995 that prohibited federal funding for converting highway signs, such as those for speed limits, to metric units."

According to: http://www.fhwa.dot.gov/interstate/faq.htm

"the National Highway System Designation Act of 1995 prohibited the use of Federal-aid highway funds to convert existing signs or purchase new signs with metric units."

It appears from my reading of the law that the prohibition expired in 2000.

Ha interesting. Didn't know abou that expiration.

> Montana is famous for its high speed limits on motorways

This hasn't been true for years. Our current speed limits are in line with the rest of the country.

Ok, I'll bite, so what are you famous for now?

I doubt a resident can accurately answer this question.

In 1995 - 1999, our speed limit on the Interstate in Montana was "Reasonable and Prudent". The federal government set a national speed limit in 1974, and it was repealed in 1995. When that happened the speed limit reverted to what it was in '74.

I was in high school for a couple of those years. I drove 120 MPH frequently. I probably would have got pulled over for that. I had a friend who got pulled over for going 90 MPH. Ultimately, I think the ambiguity of "reasonable and prudent" led to the state enacting a 75 MPH speed limit.

http://en.wikipedia.org/wiki/Speed_limits_in_the_United_Stat...

Are you saying that Montana is not known for much else other than having high speed limits?

There are two incredibly beautiful national parks there, Glacier and Yellowstone. Yellowstone is one of the best known parks in America.

Yellowstone for the most part is in Wyoming.

You are right. It has been years since I have been there. However, for some reason I remember spending a good amount of time in the Montana portion. Don't know why.

The UK and the US is essentially the same story. The British seemed furious that the EU mandated use of metric internally. But it did not force the UK to change its road signs (still in yards and miles) or what beer comes in (pints).

Nothing really changed, other than confirming by directive that EU member states uses the Metric system with one another. There are still Brits who complain that the weather reports are no longer in Fahrenheit, but in Celsius. But the EU has no control over that.

So yeah; pretty much the same. Oh and the Brits still weigh themselves in stones.

I remember during the influx of Polish workers in the UK, that a pub got into some trouble because it sold a certain Polish beer in a 1 litre glass.

I remember during the influx of Polish workers in the UK, that a pub got into some trouble because it sold a certain Polish beer in a 1 litre glass.

From what I recall, it was more that they were using Żywiec-branded glasses, which hold 0.3 and 0.5-litres respectively. UK law only allows beer to be sold in pint units.

I doubt they were doing it on purpose, but the small difference adds up quite quickly: serve 10 drinks at pint prices for only the cost of 9 pints.

They have those standards so that you know how much alcohol you are drinking. 1 pint 5% (0,5L)= ~20g alcohol = 2 glasses of anything else.

Wine 12% = 0,1L

Whiskey 40% = 0,035L

One glass is about 10g alcohol. (Posted only in liters so it easy on people who are not used to it.)

>UK law only allows beer to be sold in pint units.

Really? What are those things called Half pints?

0.5 pints is still measured in pint units.

serve 10 drinks at pint prices for only the cost of 9 pints

I guess being worried that you might not get your full ~5.68 litres of beer when drinking ten pints is very British indeed ;-)

The UK did use legislation to gradually switch to the metric system, with certain exceptions.

http://en.wikipedia.org/wiki/Metrication_in_the_United_Kingd...

One major way in which metrication is being introduced properly is via schools - nowadays schools generally only teach the metric system, and the generation below me genuinely do weigh themselves in kilos, and measure themselves in meters.

Just to backup what you're saying, I'm the generation you're talking about.

I have a vague idea of my height in feet and inches, I drink pints of beer and I drive miles in the car. That's about it. People may as well be talking to me in a foreign language if they give me imperial units outside of those contexts.

What do you measure body temperature with? Celsius or Fahrenheit?

Celsius, expecting a reading of 37 degrees. I never measure anything in Farenheit (I don't actually know how to convert to it, or what a body temperature reading in it ought to be). I do basically everything in Celsius apart from occasionally during my A-Levels (16-18) where I did some conversion to Kelvin.

No one outside the US measures in F (since the parent post is about the UK, this is a weird question :)

A canadian once told me that in canada atmospheric temperature is measured in celsius but body temperature is measured in farenheit, or maybe the other way around.

>..or what beer comes in (pints). If you read the bottom of the glass you will see the size in ml, 568ml.

You may call it a pint but officially it is a 568ml glass.

Think it's actually sold by the pint, not by 568ml. http://www.legislation.gov.uk/ukpga/1985/72/section/8

Weather forecasts in the UK changed to Celsius in the early 1960s (over fifty years ago). I don't know of anyone in the UK who complains about reports no longer being in Fahrenheit.

Liquid goods in the UK are listed in milliletres or litres. In the US, fluid ounces (fl oz) are still commonly used. (The exception in the UK is pints for beer and milk).

Similarly, walk into a UK supermarket and solid goods are labelled in grams and kilograms. In the US, it's common for goods to be listed in pounds (lbs) or ounces (oz).

Also in the UK, dimensions for goods/products is always in metres, centimetres or millimetres. A lot of people still use feet and inches to describe a persons' height.

So yes, we do use a mixture of metric and imperial in the UK. However, the UK and US are not "pretty much the same" when it comes to metric.

The one big change in the UK was greengrocers and the like being prosecuted by Trading Standards Authorities for using imperial measurements.

http://en.wikipedia.org/wiki/Metric_Martyrs

That's a typical case of theory and practice.

Yes, in theory the US is a country that supports metric. In practice, go and ask anybody in the country outside of the military for the following:

- An M10 bolt

- a 16mm wrench to drive it with

- a 3 meter long 50 mm od pvc drainpipe

- a tape-measure that measures only in metric

- a highway sign that is posted in km

And so on. See how many people can point you to any of these.

Then try this:

- a 3/8th " bolt

- a 9/16th " wrench to drive it with

- a 10' long 2" od pvc drainpipe

- a tape measure that only measures in Imperial

- a highway sign posted in Miles.

The petition is dead on in the way the US approaches the metric system, in practice it is imperial all the way. As long as the practice doesn't change what the technical situation is won't matter one bit.

The only way to get out of this is to change the law, and to deprecate Imperial in favor of metric.

The comment you replied to never claimed that the U.S. uses metric units, only that it has been legal and even encouraged since 1866. So to re-iterate, there no change needed to the law, it already allows metric just fine (as you yourself note when you mention that the government-run military understands metric).

Simply deprecating customary units won't be enough to make the switch, you would actually have to make it illegal, and Hell will freeze over before you'll see that pass in the U.S. ("Doesn't Congress have actual problems to fix???")

Actual problems like the dollar is no longer a defined weight of silver. Talk about weights and measures...

Where's the problem with that? You can price your goods in gramms of silver, if you like to. (You may have to quote dollar prices, but just adjust them daily based on the silver spot market prices.)

relevant onion article: http://www.theonion.com/articles/metric-system-thriving-in-n...

Have you ever been inside of a hardware store?

Every hardware store I've ever been to has a section for metric. Our lab, for instance, keeps a supply of bolts, and as far as I remember /only/ has metric.

Also every socket set I've ever used has a metric and standard set.

Why would you care about road signs? And why would you care about a tape measure that is /only/ in metric? The second one seems kindof silly.

The only thing I know of that isn't available commonly in metric sizes are machining tools like mills. As far as I know, machining is always done in "mils", or thousands of an inch.

Or if you happen to ask anyone who works on a vehicle that isn't from one of the American manufacturers. My Toyota used all metric, AFAIK, and all of my motorcycles have used metric. I can't say I've ever even used the standard set of tools that came with my toolset (which had both metric and standard).

Toyota is weird, in that all of the nuts & bolts on their cars are metric, but their tolerances in the factory service manual are listed in thousandths of an inch. I did a double-take when I saw the deck flatness tolerance of ".002" for my car, for example.

My Ford car is all metric as well.

> Have you ever been inside of a hardware store?

I believe so. Maybe a couple of times. Or maybe I practically lived in one for a couple of years.

Would this do for you?

http://pics.ww.com/v/jacques/trips/jansvisit/?g2_page=6

Yes, there is a section for metric in the hardware store.

It's the bit at the back with about 1/2 the sizes missing and only the stuff that you don't need in stock. I've had a machine shop in Canada (which officially had metric) and it was quite hard to get metric stuff. So hard that in the end we standardized on Imperial. In the US it was way worse.

Socket sets have standard and metric. Metric mostly for working on Japanese or European cars. But the most tools 'at hand' will be imperial. Maybe your experience is different but I've had plenty of bolts on my Japanese car wrecked by a shop putting imperial tools on them and plowing ahead. Works especially good if you use airtools, instant roundness.

You care about road signs because they're a sign that you really are standardizing. If your road signs are still in Miles then you're not a 'metric' country.

And you care about a tape measure only in metric because that's all you use in a metric country.

Machine tools - of which I owned a small fortune worth of - have things called morse tapers for the various tool bits. Morse tapers are adapters that allow you to quickly switch bits, most of the tooling that fits them is in Imperial. Collets, the elements that hold tooling for a mill or a lathe are all in imperial sizes. Unless you order from a very large catalogue it is very difficult to get mills in metric, but that is much more frustrating is that it can even be hard to source drills in metric.

Machining is done to thousands of an inch in the US. The rest of the world uses 1/100th of a mm for both turning and milling, and a series of fittings for more precise work.

The good news is that the bigger bearing companies all do carry metric if you need it. And if they don't have it in stock it 's usually only a day away.

Unless you've actually tried to design a somewhat complex chunk of machinery you might be given the impression that 'metric is easy'. In practice stuff like shafts, gears, supports and so on are all easier to source in Imperial than in Metric both in the US and in Canada too.

You want to order in Imperial, just one moment while I get your order form the warehouse out back. You want to order in Metric. That's perfectly fine, we're a metric country after all. Would it suit you to pick your order up in early march, possibly the middle of april before it is complete?

Outside of cars, roughly every power tool, piece of electronics, cabinet (35mm), etc needs metric sockets or hex keys.

I have built plenty of complex machinery. It's actually significantly easier for me to source 50mm flywheels/pulleys, or v-belts, or whatever, than it is to try to get someone to give me reasonable tolerances on imperial.

While it's true machining is done to thousandths of an inch in the US, most of those machining tools are using chucks/collets/etc whose sizes/TIR/etc is all actually metric.

(IE the 1/2" chuck/collet/whatever is really machined to 12.7mm)

Good to see that the situation is improving. The more the US imports the more stuff will be in metric, it's unavoidable.

But I'll believe it when the construction industry let's go of the foot and the inch.

A 12.7 mm collet is not a metric collet. A metric collet would be a 12 or 13 mm.

My point was exactly that the construction industry and others already deals in metric whether they know it or not. Yes, they spec 2x4's, and 3/4" CDX sheathng, but every piece of sheathing they use is actually made to millimeter specs, not imperial specs.

This was my point about the collet, too. It's true they collets are not meant to be holding metric sized end mills/etc, but the collet itself is milled using metric sizes. They are not milled to 0.50000, they are milled to 12.70mm.

Good. So that's the source of your confusion then.

I'm glad we got that cleared up. Since the Inch is specified as 25.4 mm you can convert any measurement in Inches into an exact equivalent in metric. But that does not make it a metric size.

Inches: 1/8, 1/4, 1/2, 3/4, 1" etc and various measures in between (5/32nd for instance).

Metric: 1mm, 2mm, 3mm, 4mm, 5mm, 6mm, etc. and various measures in between (5.5 mm for instance).

So you buy your lumber in Imperial measures (apparently except for thickness), and the rest of the world buys theirs in meters (or mm). That's the difference between 'working in Imperial' and 'working in metric'.

Uh, if something is milled to a metric size and tolerances in metric, it is in fact, a metric size, regardless if it happens to match some imperial sizes. There is no requirement that metric sizes be only integer whole numbers, and if you are going to claim that, for example, all lumber purchases outside of the US are done to exact integer metric sizes, that's just false. It may be the construction industry purchases common sizes in MM, but that's not really the same.

If you want only integer or half integer metric sizes, that's something different than "metric sized"

That said, rough lumber outside of plywood/framing lumber is weird in both the US and Europe anyway. Nobody is trying to hit any exact sizes of anything, except that the lumber needs to be able plane down to certain thicknesses. Grading is based on percentage of clear cutting, not on thickness or width or length. If your lumber supplier doesn't give you lumber in thicknesses that can be planed down to the right size, you get a new supplier. Same in Europe.

Lumber isn't 'weird' the sizes make perfect sense, if you're constructing something beyond a picknick table you'll see the logic immediately. Nobody said anything about integer whole numbers.

But I can't seem to get around your mental block that the system you are working in is Imperial, not metric so I'll leave it at this.

Actually, the sizes are in fact, simply odd left-over relics. This is pretty well documented history about how studs came to be nominal vs actual.

Same with hardwood lumber, in fact.

Considering i build about 20 pieces of fine furniture a year, and have built 3 houses, all of which are things "beyond a picnic table", as well as being active in a number of the industry associations that define this stuff (in my spare time), and you apparently know more, maybe you could explain the logic to me.

FWIW: I have no mental block, i actually work in both systems all the time. The whole exercise here has been pointing out your claims are wrong, not about me at all.

Lumber isn't 'weird' the sizes make perfect sense...

If you go to a home depot and ask for something 2x4x8ft, it will not be 2.00 by 4.00 inches or 8ft long, when measured with a caliper. Its weird in the sense that the stated sizes are only approximate, quite unlike hardware or fasteners, wrenches etc.

Those sizes are what they are because of the way lumber is produced. When the mill mills them they're 'true'. But they're also rough. So then they get planed which takes a bit of wood away from all four lengthwise sides.

The keep their name though. This is a convention and a quite confusing one if you're not familiar with the process.

What does it mean to say that "the 1/2-inch chuck/collet/whatever is really machined to 12.7mm"? 0.5 inches is exactly 12.7 mm, so what else would it be machined to?

Yes 0.5 inches would be exactly 12.7 mm but that comes from the way the inch is now defined (which is 1 in equal to 25.4 mm) as opposed to the earlier definition (i.e. 1/12th of a foot (this definition being the older imperial definition). machined to 12.7 mm simply means that the original imperial definition is abandoned for imperial units and although the chuck/collet/etc is still sold as 0.5 inch chuck/collet/etc; when constructing it, it was measured in the SI units of mm for precision purposes.

> Yes, there is a section for metric in the hardware store. It's the bit at the back with about 1/2 the sizes missing and only the stuff that you don't need in stock.

So, would your proposed law to switch the USA to the metric system require hardware stores to stock every size and always have what you need in stock?

This is anecdotal, but I recall that Alabama put up highway markers in kilometers during the 1990's [1]. It confused people, and they cancelled the program. You can still find signs that haven't fallen down or been stolen in some places.

[1] http://lamar.colostate.edu/~hillger/signs/AL.html

This is a bunch of fictions. Americans with wrenches tend to have both SAE and metric sizes. The thread pitches of metric bolts differs from SAE standards, and drain pipes are sized on inside diameter not outside because ID is relevant to capacity.

Tape measures have standard units because they're standard where tape measures are used - in construction.

Where it makes sense, metric is common, e.g. soft drink bottles.

> This is a bunch of fictions.

Not really, those are all pretty practical examples. I've dealt with each and every one of those.

> Americans with wrenches tend to have both SAE and metric sizes.

The metric ones will be brand new if they have them, the imperial ones will be well worn.

> The thread pitches of metric bolts differs from SAE standards

Indeed they do. In the EU Ford vehicles are all metric unless they were private imports from the USA. I'm not sure what the situation is today but when I still lived in Canada the ford we had had all imperial sizes bolts as far as they were exposed.

> Tape measures have standard units because they're standard where tape measures are used - in construction.

Yes, and as long as you don't change that that's they way it will stay. The English drive on the left because they do. But that doesn't mean they can say that they've adopted driving on the right side of the road because they could. They haven't. So construction is almost entirely in Imperial.

In a metric country, metric is used everywhere, because it makes sense.

The U.S. auto-industry typically uses metric fasteners. In my experience, that's pretty much been the case since the early 1980's - though that experience is mainly with GM products.

Some of my older metric tools predate that. I owned a '64 Baja bug - thereby learning the art of static timing adjustment.

Changing tape measures isn't going to change US construction practice. Lumber has to change. Cold formed steel manufacturing standards have to change. Steel mills have to change.

All the engineering tables have to change. And insurance underwriters have to be willing to eat claims based on any confusion which this creates - it's kind of like the Hubble telescope without NASA redundancy, except that people will probably die.

The baja bug is a VW beetle re-run (so German, hence metric).

Agreed with all the other points and that is exactly why I think this will not happen.

I used to work as a professional mechanic and the auto industry used to be split, with American brands using SAE and imports using metric. This was all changing fast in the 90s such that pretty much everything is metric on cars these days. Still, there are a few exceptions here and there.

Two liter bottles are an anomaly. Every other pop container is in ounces. Cans are 16 ounces and bottles are usually 20 ounces.

I can't think of a situation where "metric is common" for consumer items.

California wine 750mL bottles. Obviously the imported stuff is in mL but so are the domestics.

Every OTC pharmaceutical I've ever seen, pretty much.

There's a pretty weird combination of liters and ounces in soft drinks. 2 L and 20 oz are very (most?) common for bottled soda. 1 gal is common for bottled water, but for individual bottles, 0.5 L (16.9 oz) is common. 1 L and 1.5 L bottles of various beverages are not unheard of. Cans of soda are generally 12 oz, though 16 oz and 24 oz are not uncommon among beers. Wine, as mentioned below, is often 750 mL, but liquor is often sold by the quart.

So I wouldn't say the 2 L bottle is the sole anomaly, but metric is definitely not the prevalent system for beverages.

Some of your examples are good, but many aren't based in reality for the US consumer. A lot of consumer goods are manufactured overseas, then imported to the US. The manufacturers of these goods rarely create custom versions that rely on inch-based hardware. The ISO nomenclature isn't very common, but 16mm wrenches are very common. Pretty much any US resident who wants to work on their car or assemble products without using the supplied stamped wrenches has to have both imperial and and metric tools. I've got a whole tool chest full of that mix in wrenches, sockets, and hex drivers.

When it comes to highways and tape measures, you're right though. A tape measure is most commonly used in carpentry, which is almost entirely imperial. Our cars all have speedometers that display MPH in large type, so I don't see that changing without some mandate.

Does anyone else on HN work on their own car? My ancient unbreakable domestic mfgr '97 GM car is all metric. Right off the top of my head the oil drain plug is a M12-1.75 bolt. I just replaced the battery two weeks ago, all metric (I think they were M10 bolts? I was in a huge hurry). Seemingly everything on my GM car is metric, and it was built 15 years ago, I can only imagine how metric everything in auto-land is now.

That would make good sense. What about things like wheel nuts, hitch attachements and so on?

The ford I had had a surprising amount of imperial on it about a decade ago. Presumably under the hood and inside the engine it was all metric though.

"What about things like wheel nuts"

I can verify its 30 mm with my wheels/hubs on my car. Supposedly that's "unusual" and most cars that size are 28mm or 32mm so people end up mystified why their 28 doesn't fit something that looks visually at a distance like a 28, or they use a way too big 32 and neatly round off the corners of the nut when it slips. I imagine using an imperial impact wrench is an effective way to round off the wheel nuts on a Saturn.

I would imagine if you bought aftermarket wheels/studs alloy or steel you could have most any size within a narrow range that's compatible with the hub.

"hitch"

LOL at the idea of my tiny little 2-door subcompact towing anything like those giant RV trailers. I do know standard american trailer hitch on pickup trucks has been 2 inch square for a century or something like that. Kind of like how we're not going to change every piece of railroad track and rolling stock in the USA to a metric equivalent rail gauge any time soon, until the end of time we'll be stuck with 50.8mm trailer hitches. I bet you could slam a european 50mm in the hole within manufacturing/rust tolerances.

32mm is used all over in GM world - 32 just happens to be barely smaller that 1 1/4" inches so it keeps people that only have SAE sockets happy. 1

I daily-drive a 1997 Ford Ranger pickup. The engine was produced in Cologne, Germany, and thus everything under the hood is metric. The body & chassis was built in Dearborn, Michigan, and thus everything not under the hood is SAE.

That perfectly matches my Ford experience.

Completely depends on the car. Wife has a 2006 Mariner, it has 19mm wheel nuts. My '91 Explorer is 5/8" or 9/16" or so (I don't remember). I also have a BMW that's 100% metric of course. And a '68 mustang that's 100% SAE.

The explorer is metric in a lot of places. The engine is SAE since it's based on the 302 which was originally designed in the early '60s. Pretty much anything that was designed from the mid 80s or later will be 100% metric hardware unless it needs to work with something that isn't. And even then it'll will sometimes be metric until it hits the non-metric piece. For example, the Tremec T-5 transmission is metric but mates up to the Ford 302 which is SAE.

So basically, it's usually metric except when it's not.

GM and Ford use metric for the last 20 years - but on a lot of their 'easily accessible' bolts, the heads are sized just enough to work with standard hobby imperial sockets. If I remember - That M10 will fit a 3/8" socket too, and M13 is used all over the place and will work with 1/2" socket.

On my wife's Suzuki their M10 will not work with a 3/8" socket, and if you get into anywhere serious on a GM or Ford - those bolt heads will be exact metric with no room for imperial.

I have all of those things except the drain pipe and a highway sign.

Every socket set i have contains both SAE and metric. Half of my power tools are in metric (festool).

All plywood that you buy from the hardware store in the US is really metric sized nowadays.

Every screw/fastener on every tool I own is metric or metric sized. I haven't used my SAE hex keys in eons.

When you say 'metric sized' do you mean 1250x2500 or do you mean 1219.20 x 2438.4?

Home Depot does not agree with you.

From http://www.homedepot.com/h_d1/N-5yc1vZbu0m/h_d2/Navigation?c...

this is my absolute favorite: "5.2 mm x 2 ft. x 4 ft. Sanded project panel", all the rest is in Imperial.

I mean that nominal 1/2" plywood is not 1/2" anymore, it's undersized to 12mm.

The width/length is not in metric, the actual thickness is, though they come up with an imperial equivalent that is within a few thousandths.

In other words, they tell folks 1/4 plywood is 15/64, 1/2" plywood is 15/32, etc. In reality, they are undersized to the nearest mm.

Like jaquesm says, I just bought plywood at home depot and it came in 6.45mm thickness, 24"x48". I don't know how you get 6.45mm either in metric or imperial, but it's clearly not "sized in metric".

Thickness wise, they are sized in metric. If you got 6.45mm, someone messed up :)

No non-hardwood plywood, even 1/4" plywood, is oversized, and 6.45mm would be oversized at .2539 inches. If it was actual 1/4" (hardwood plywood), it would be 6.4mm per APA (american plywood association) standards.

Outside of hardwood plywood, thicknesses are really done in metric.

1/4" nominal plywood nowadays is sized at "15/64" imperial, or in reality, 6mm.

1/2" nominal plywood is 12mm, or "15/32".

(the actual sizes are metric, but are close enough in tolerance to imperial /32 or /64 sizes that they work)

The only plywood you will find that is "actual" size in imperial is domestically produced hardwood plywood.

This is not a large percentage of produced plywood :)

>The only plywood you will find that is "actual" size...

Actual thickness you mean...

All construction sheet goods available in the US come in 4x8 sheets (drywall excepted, which I believe can be as long as 12').

Just because you can express "4ft by 8ft" as "Xmm by Ymm" (and that very well may be the official spec) doesn't make it 'metric' lumber in any meaninful way.

Actually, not all construction sheet goods come in 4x8 sheets, you have things like cement boards, which are 3x5 sheets. Same with some fiber based sheathings, some fire-code panels, etc. There are actually plenty of non-4x8 construction sheet goods.

In any case, let me make this very simple:

All non-domestically produced (and most domestically produced) sheet goods are produced to metric sizes that are close to 4ft x 8ft x whatever thickness. They are whole number integer metric sizes. They are metric sheet goods. They are produced and measured metrically by every producer and exporter.

They get sold as imperial sizes in the US. However, the fact that they are close to some imperial size does not make them imperial sized lumber in any meaningful way.

If i take a bunch of things that were produced as squares, sell them as circles, and people keep calling them circles, that doesn't make them circles.

You can call a 4ft x 8ft x 1/2" piece of sheathing 4ft x 8ft x 1/2" if you like. But it's neither 4ft, nor 8ft, nor 1/2".

If you don't believe that sheet goods produced and measured metrically to whole number metric sizes are metric sized simply because someone in the US decides to call it something different, we'll have to simply agree to disagree as to whether they are metric.

I'm happy to agree that folks in the US don't work with the metric system intentionally, but they are working with it, whether they know it or not.

This whole discussion started because one of the premises given was that things like construction sheet goods (and lumber, but let's stay simple) would have to change for folks to be able to use the metric system in the US.

As i've shown, this is simply false, they just need to pretending they are imperial sizes, because the construction sheet goods are already done to metric sizes.

0.003" could easily be thermal expansion or humidity.

I worked in oilfield and petrochemical construction and manufacturing for almost ten years, and I can say that we almost never used metric. I think in the ten years, I worked on two projects that required metric bolts and fittings, both of which were for Japanese companies. Retraining the workers to use metric for these projects was a battle in itself.

We built structures and equipment that went around the world... all using imperial.

I like in the US and am from EU. As a result, while I try to ask for things in imperial units, I happen to ask for tools and related things in metrics from time to time. My experience is as follow:

- most people actually just get me exactly what I want

- nobody ever complained "why do you ask metrics, you're in the US we use imperial!!", ever

- nobody ever told me "I don't know what that makes in inches, do you know it in inches?" (or similar), ever

So while I'm just one person and all, I still have a feeling this could eventually work.

Oddly enough, highway signs in km can be found for about 20km north of the border town of Nogales, Arizona.

This is true. However, this is not insurmountable:

http://xkcd.com/526/

The key is, I think, start with the measurements you use in your daily life and start estimating in those terms. Use it in the office. It might be accelerated if there's a metrics app for the Google Glasses, automatically converting signs into metric. You start saying, "dude, that bouncer must be two meters tall!" and getting everyone around you to convert.

I live in a metric country so I agree with everything you say, though a metric only tape measure is possibly less important. Actually I have two tape measures handy, one is metric only and the other has metric and imperial units. I think you'd expect to see both units for quite some time after conversion. Interestingly the one that is metric only is a style that tradesmen often have. I gather if you are measuring things all the time, you'd only want to deal with one set of units. So perhaps the option of having a metric only tape measure is still useful.

"the imprecise Imperial Unit"

The word "imprecise" is also factually incorrect. AFAIK, all Imperial units are now defined in metric. An inch is not "approximately" 2.54 centimeters, it is defined to be 2.54 centimeters, or, if you prefer, 2.540000000000... centimeters. A pound is defined as 0.45359237 kilograms.

It may be very precise specification of a value that is unpleasant and hard to work with, but there is no more and no less precision in the Imperial system than there is in the metric system, because technically Imperial is now just a flavor of metric. In that sense, we are metric already. This is definitely not the sense that people mean, but it is not entirely invalid, either.

As long as you aren't a surveyor, that is... that industry has stuck with the previous American standard of 1/39.37 meters, for obvious reasons.

Land surveyor here. I understand the issues in play here deeply. Field calcs, just to name one thing, would be greatly eased by metric. But here's the thing: you can't make an old surveyor think in metric. The way I visualise distance is Imperial. This is deeply ingrained.

Well, that, and it would be a monumental task to update historical metes & bounds measurements for most of the eastern states. Or so I assume.

Only way to retrain is to either have the young generation abandon the old way, or to have the old guard exercise flexibility and neuroplasticity. You can change habits, but it takes effort and commitment.

I say that, and I still stick to my Vim and won't use Emacs keybindings :-D

It wasn't as hard as I expected to make the switch in my mid-twenties. I know that is not the same, but it is not entirely different.

I prefer 2.53999999... centimeters, but to each their own.

That'd be 2.5400000000.... cm

The factoid I learnt in my childhood of an inch being 2.539954cm is now wrong?

Where I live we use metric for everything, except monitor screen size and hard disks dimensions (5.25', 3.5').

Food stuff is typically bought in dekagrams for meat or cheese and kg for fruits or grocery (you skip "gram" in informal language, so it's "30 deko of this, and kilo of the apples, please").

Drinks are sold by liters, soda mostly in 1.5l ("one and a half" in Polish it's one word), alcohol in 0.75(default), 0.5 ("a half"), or 0.25 ("a quarter"). Everybody are used to it and it's quick.

Prices everywhere are per kg, sometimes also per 100g (I don't understand why, dividing by 10 is automatic, but anyway).

Ah, so it's not legal definitions that make street signs show distances in miles and speeds in miles per hour?

And if it's indeed the law since 1875, we wouldn't have needed the Metric Conversion Act from 1975, would we?

We're still on Imperial units because the U.S. commitment to metric units has been patchy and haphazard since the beginning. Unless we're willing to mandate the use of metric units only for all state business, especially in education, we're going to be stuck with furlongs per fortnight.

In France and Belgium, the metric system is used everywhere, with a few exceptions. Inches are used for hard disks, floppies and computer monitors (but not for TVs).

In open air markets, vegetables are sometimes sent by the pound (500g, une livre in French). That's about it AFAIK.

No, you don't understand, the government needs to use more violence to make the wonderful metric system more common.

How are laws passed in the US when it comes to weights and measures? Are they primarily passed in metric or imperial? That right there will be your answer, regardless of whether some old law merely adds an official system.

> A Facebook friend with a scientific education recently told me about the saying "A pint's a pound, the whole world round." If the United States begins using metric-standard units more for selling foods and the like, then perhaps a half-kilogram (500g) package will be considered to be one new "pound," just as a half-liter (500ml) package will be considered to be one new "pint."

That's what happens in Colombia. We ask for a pound of meat, and we actually expect 500 grams.

Also we measure fuel in gallons, while the milk is in liters.

> "A pint's a pound, the whole world round."

A UK pint is 568ml, which is some way off 454g. Unlike the US pint, which is much closer at 473ml.

British people generally like the old British "Imperial" system. It's ours! Millimetres and grammes are associated with Napoleon and the E.U. (which are also unpopular in the U.K.).

In British supermarkets, milk is usually sold in pints, except on the packaging it has to say "768 ml".

(By the way, I think your (U.S.) pints aren't the same as our (Imperial) pints.)

Often you see milk in 1 litre bottles instead. I suspect the reason this goes on is because it looks like it's 2 pints, but of course it's actually less than 2 pints. So it's basically just a sales trick to make the milk look cheaper and to confuse customers.

Cream is practically always sold in 1/2 pints, which on the packaging is written as 284 ml. As far as I remember, I've never actually seen it written as 1/2 pint, but that's what it is. I think a lot of people don't even know that it's 1/2 pint of cream.

We still use the Imperial system for lots of other things, e.g. beer, waistlines, car speeds, etc.

Furthermore in speech, the idioms "kilometrestone", "millimetreing forward", "give a millimetre and he'll take a kilometre" just don't sound as good!

In the markets in Holland, you often hear people asking for a "pond" of carrots, or whatever. (You also see it written by the stallholders as "ponds".) In this case, they mean 500g, however (according to Wikipedia) a Dutch pond was actually 494.09 g. (An Imperial pound on the other hand is 453.59 g).

(By the way, I find it a bit embarassing to write "Imperial", but I've stuck with it.)

I would also like to point out that the French and the Italians still measure their computer monitors, and their bicycle wheels in inches! Not their horrible millimetres.

My Dad (who is an architect) tells me that boilers are still measured in BTU's. I don't know if that's still true.

I have to say that the Metric system is definitely easier when it comes to (a) science, (b) surveying, engineering, etc.

For everything else (e.g. toast, road signs, boilers, cream, trousers, etc.) I'd rather have Imperial units.

Ireland has converted mostly to the metric system, we switched to kilometers for speed limits in 2005. To be honest you get used to it pretty quickly. There are a number of items, particularly those that are traded with our neighbours in the UK that are shown as both metric and imperial. You still get a pint of Guinness in the pub but all bottles and cans of beer are in metric.

http://en.wikipedia.org/wiki/Metrication_in_Ireland

Metrickery is a socialist plot to weaken America. First it's units of measurement divisible by ten, then it's universal health care, then gun control, and finally off to the gulag for the last remaining freethinkers.

Sadly, there are people who believe more of less exactly what I just wrote.

Actually, the "Europe is better and the US is inferior" mantra, which is very widely held in the American left-of-center, is a significant factor in all of those.

As a Canadian, I'd be inclined to call it the "every other industrialized liberal democracy on earth is better" mantra. Countries tend to converge on an optimal balance of individual liberties and social protections because it measurably works.

The US is a notable outlier, and the various comparative social and economic indicators are pretty damning evidence that the continued American insistence on an 18th century approach to governance actually is inferior to a number of other approaches that have been more inclined to take evidence-based best practices into account.

> Countries tend to converge on an optimal balance of individual liberties and social protections because it measurably works.

That's just utter nonsense. What measurement are you optimizing for?

What makes you think that moving the US to the left moves it closer to, say, Germany, instead of closer to, say, Brazil, India, and Mexico (which is what I think will happen)?

And even if it did move it closer to Germany, I wouldn't want that, which speaks to the fact that your "measurably works" claim probably refers to some non-objective sense of optimality.

> the continued American insistence on an 18th century approach to governance

That's a straw man. Predominating sentiments in the GOP are strongly contra the Founding Fathers. I mean, George W. Bush greatly expanded the welfare state.

Society should optimize for happiness. It's not measurable, but you can estimate it (for example you can estimate that average German is happier than average citizen of North Korea). My vague definition happiness is this: Let's say you must choose between 2 states of mind and you'll spend the next hour in the selected one. Before your choice, you can try each of them by clicking some button. The one that you choose has higher "happiness quotient".

So let's draft 1% of the population and place them in a large underground bunker at birth. They will never be allowed to know anything about the "real world," and they will provide all the labor, engineering, and scientific research for the other 99%, who get to everything for free. Does that sound like a good society to you?

No, because this very probably wouldn't increase average happiness:

1. The 1% would be less happy. 2. Lot of the 99% would feel guilty (which lowers happiness). 3. The 1% would probably be less productive than if they were free. So the only benefit for the 99% would be that they consume less.

By the way, this system to a certain extent exist in our society (cheap labour in China for example).

> What measurement are you optimizing for?

Take your pick. The US is at or very near the worst among OECD countries in: infant mortality, child poverty, child health and safety, life expectancy at birth, healthy life expectancy, rate of obesity, disability-adjusted life years, doctors per 1000 people, deaths from treatable conditions, rate of mental health disorders, rate of drug abuse, rate of prescription drug use, incarceration rate, rate of assaults, rate of homicides, income inequality, wealth inequality, and economic mobility.

All of which can be blamed on not using the metric system.

Most or all of which would not be helped by liberal attempts to emulate Europe.

For example, high child poverty is to be expected in a country that harbors many poor immigrants from Latin America.

For another example, high rate of incarceration is largely to be blamed on the "War on Drugs," which has the same effect as the prohibition on alcohol did.

For another example, low rate of doctors is largely to be blamed on the fact that medicine is a guild (as in, midieval guild) where med school is super tough to get into, doesn't select for competency as a medical practitioner, and creates a "class hierarchy" within medicine where a highly-trained nurse can perform as well or better than a doctor in many common situations, but is not legally allowed to practice in that capacity.

This could go on and on.

Overall, American liberals want a society where everybody gets whatever they demand, to the degree that there is enough to go around, except the actual producers. That society already exists, and it's called India.

> Most or all of which would not be helped by liberal attempts to emulate Europe.

You mean the rest of the industrialized world, not just Europe.

> high child poverty is to be expected in a country that harbors many poor immigrants from Latin America.

You mean unlike a country that harbours many poor immigrants from Northern Africa, the Middle East and Eastern Europe?

> high rate of incarceration is largely to be blamed on the "War on Drugs"

Yes, and it is the conservative right that most strongly favours continuing the War on Drugs. Those left of centre liberals you don't like generally favour ending the war on drugs and following a more - dare I say - European approach to legalization. (Sadly, Canada's Republican-lite Conservative government has taken a more American approach to the War on Drugs, establishing mandatory minimum sentences and other punitive measures that have already failed in the US.)

> low rate of doctors is largely to be blamed on the fact that medicine is a guild

That's true across all the industrialized countries, but the other countries are much better than the US at achieving a higher rate of doctors and much better overall health outcomes, despite spending only 40-70% of what the USA spends on health care - and running various incarnations of universal health coverage.

> American liberals want a society where everybody gets whatever they demand

That's a lazy straw man attack. American liberals, like liberals in other industrialized countries, want their country to value human rights, pay attention to evidence-based public policy and invest enough in public social and physical infrastructure to ensure everyone has an adequate standard of living and the opportunity to work hard and prosper.

Ironically, the USA has among the worst levels of socioeconomic mobility in the OECD. Poor Americans are more trapped in their poverty than poor people in countries that do more to level the playing field so everyone has a fair chance of escaping poverty.

> despite spending only 40-70% of what the USA spends on health care

Right. And if the USA tries to emulate Europe in healthcare more than we alreay do, we will end up wasting even more money. There is no solution to be had here through more regulation.

> value human rights

> ensure everyone has an adequate standard of living

Contradiction. But providing a moral basis for individual rights requires understanding a complete philosophical system, which is out of the scope of an HN comment.

> ensure everyone has an adequate standard of living and the opportunity to work hard and prosper

You're asking something that may be outside the scope of reality.

> Poor Americans are more trapped in their poverty

As someone from a poor part of rural eastern North Carolina, all I can do is LOL at this, because it's utterly, utterly false. That is a complete myth. I mean, we already have free universal education, de jure through high school and de facto through college.

> if the USA tries to emulate Europe in healthcare more than we alreay do, we will end up wasting even more money.

The evidence is that American health care costs would go down significantly, given the clear correlation across industrialized countries between the extent to which health care spending is private and the overall cost (either per capita or as a share of GDP).

> Contradiction.

It's not a contradition, the latter follows necessarily from the former. It's why nearly every industrialized country has converged on public health, public education, public health care, affordable housing, and so on.

> But providing a moral basis for individual rights requires understanding a complete philosophical system, which is out of the scope of an HN comment.

Or we can dispense with the 18th century a priori legerdemain and just recognize human rights as a self-evident basis for a fair, just and humane society.

> You're asking something that may be outside the scope of reality.

And yet the rest of the industrialized world does a much better job of it than the United States.

> As someone from a poor part of rural eastern North Carolina, all I can do is LOL at this

The plural of anecdote is not data.

The working of any given balance of liberties and social protections is a phenomenon observable only in time increments over centuries, or possibly millenia.

There are many examples of "liberal" and even "democratic" or "republican" governments / societies that lasted for centuries before failing into tyranny and / or to foreign domination. The US Constitution attempts to correct the failings of each of those examples. Saying it has worked so far is declaring the weather today, all day long, was great -- at 9:30am.

Saying the French or Germans have demonstrated their solutions, at that time scale, is just nuts.

It must be fun to live in a world where everyone who disagrees with you is a moron.

It must be unpleasant to assume that everyone who disagrees with you thinks you're a moron.

Every objection that is being raised on this thread was raised when other countries enacted metrication. You are free to read the history of these processes. Nations did not collapse and people learned how to use new units.

http://en.wikipedia.org/wiki/Metrication

I would more support a petition that was well and cogently written, however.

We already have the metric system. An inch is defined as 2.54 centimeters. Et cetera. I can't think of a single way in which we're NOT metric, except that stubborn people refuse to let go of gallons, miles and pounds.

Every item you buy in the stores will be measured in metric units. Just because we call it a gallon doesn't mean it isn't actually 3.785 liters. And just because the serving size is a cup, doesn't mean it isn't actually 240mL. And check the nutrition label sometimes. It's all metric.

http://www.fda.gov/ucm/groups/fdagov-public/documents/image/...

So what's the problem again?

> So what's the problem again?

America sucks and is like the worst thing to ever happen to the world. Or something, it all blends together eventually.

Oddly no one ever makes a serious push to ban languages other than English or Mandarin Chinese throughout the world, or currency other than USD which would actually have beneficial effects on global interaction. Instead they compare the U.S. to Myanmar as if Americans should seriously be offended by that.

It very likely is never going to happen. The main reason for resistance apparently is the various land boundaries that would have to be re-scaled to metric, which would be a source of endless legal wrangling. Already houses in the US have the longest history attached to them, sometimes all the way from the homesteading days if the plot is old.

I've used both metric and imperial, for construction imperial is lots easier, for physics and other things that involve frequent conversions metric is far easier.

The Canadians officially have metric, try buying a 250x125 sheet of plywood. Everybody will look at you as if water is burning.

>Already houses in the US have the longest history attached to them, sometimes all the way from the homesteading days if the plot is old.

That's young by European standards. Somehow we managed the conversion.

How many European countries are there? How many of them have had the same government for 230 years?

The US surveyed and then subdivided much of a continent into townships. Land was sold and granted by the section, halfs and quarters thereof. Flying over the Midwest, the manifold rectangles on the ground show how problematic even the slightest of conversion errors would be.

Maybe it's technical debt. But it exists because the legal system is stable.

How many of them even have the same borders over the last 230 years? I'd wager very few.

I think the reference for US borders is probably better put at 150 years - outside of Hawaii.

We got to do a little do-over due to an ambitious little French upstart called Napoleon. That reboot fixed a lot of our problems. The US never got to even think about a do-over until they were so invested in Imperial that changing was very hard.

I was reviewing some old deeds that a relative had. A particular inclusion of land was expanded (they transferred some land to expand a township cemetery). The deed before the transfer is specified relative to survey markers and such. The deed after the transfer gives the corners as lat/long coordinates.

I guess there is some room to argue about the representational accuracy of a chosen coordinate system, but it would take quite a bit of a crazy to keep on pursuing it (especially in areas where public roads already impinge on things far more than an inch or two).

Of course it would still be pretty pointless to engage in a wholesale conversion of all that information (and I guess the lat/long stuff isn't really metric...).

Common sense never stopped most lawyers from not litigating when they knew their case was lost. Present company excluded.

> The Canadians officially have metric, try buying a 250x125 sheet of plywood. Everybody will look at you as if water is burning.

Really? I picked up a 1.5m^2 sheet of aluminium for a project fairly recently (Australia). I have literally 0 idea what that is in feet/inches/furlongs.

Australia is a ways away from Canada and aluminum isn't plywood.

> the imprecise Imperial Unit

englilsh units aren't any less precise than SI/metric ones. They're just more awkward and less used worldwide. The cases which I find particularly irritating in US units are lb mass vs. lb force, and HP/BTU/foot-pounds/calories/Calories (and kWh) when all you need is a J.

I understand and agree that metric is strictly better, how much better is it? Do the benefits outweigh the costs of changing the whole system?

What about the recurring cost that we have now of using both systems?

I'll play along. What "recurring cost"?

As mentioned elsewhere on this page:

http://news.ycombinator.com/item?id=4996563

http://news.ycombinator.com/item?id=4996646

And also things like the occasional cost of writing off a Mars probe (and they aren't cheap) because not enough was spent on checking unit conversions.

I could care less about using metric, but don't touch Fahrenheit. Celsius (water based) is inferior to Fahrenheit (air based) for those of us whom just so happen to reside in the atmosphere instead of the sea.

It's more accurate to say Fahrenheit is brine based. 0°F was based on the freezing point of a brine solution used by Ole Rømer: http://en.wikipedia.org/wiki/R%C3%B8mer_scale

Might as well start now - these things take time. In Norway, we introduced the metric system in 1889, but there's still a lot of non-metric measurements still around, at least in common speak.

* Length of a boat are measured in feet.

* Lumber is measured in inches, two-by-four and so on.

* Most engines are measured in horsepower(though nowadays the kw/h is usually given as well).

* Firewood have different measures, most of them derived from the pre-metric system.

* distances at sea are measured in nautic miles

* Boat speed is measured in knots. (not sure what the status of these last 2 is regarding SI these days).

Boat speed is measured in knots.

Knots are non-SI, since they're based on the non-SI nautical mile (1 knot = 1nm/hr). But they are a good example of why context is important; the nautical mile is absolutely superior to the kilometer for use in navigation (at sea or in the air). Forcing the SI unit there would actually make the relevant tasks more complex and more difficult.

"the nautical mile is absolutely superior to the kilometer for use in navigation (at sea or in the air)."

Why is that?

It solves headaches that come from trying to project the not-flat earth onto flat charts.

As Wikipedia puts it:

"In most projections, scale varies with latitude, so on small scale maps, covering large areas and a wide range of latitudes, the linear scale must show the scale for the range of latitudes covered by the map."

"Mariners generally use the nautical mile, which, because a nautical mile is approximately equal to a minute of latitude, can be measured against the latitude scale at the sides of the chart."

On earth, the meridian has an approximate length of 20,003.93m.

    20,003.93km / 180 / 60 ≈ 1,852.22m ≈ 1,852m = 1NM

Note, however, that

    20,003.93km / 200 / 100 ≈ 1,000.20m ≈ 1,000m = 1km

so if we used gradians/gon where the full turn corresponds to 400 instead of 360, the kilometer would be an approximation as good as the (international) nautical mile.

* Lumber is measured in inches, two-by-four and so on.

Q: How many inches wide is a two-by-four?

A: 1.5" x 3.5"

Water is the most important substance for life in Earth.

It boils at 100º centigrades and freezes at 0º centigrades

0.1m³ is one liter (1L) of water, so 1m³ is 1,000 liters of water

1L of water is 1 Kilogram

The imperial system is awful, please bury it.

I think most engineers would naturally support this idea. The reality is that doing something like this is pretty tough because the current system has so much weight. It's akin to asking a company to abandon a perfectly functioning legacy software system just so that someone can rewrite it.

My dad was an engineer with Caltrans and he told me about how California was ready to make the switch. It was going to be a gradual transition where signage would start listing both metric and imperial speed limits. They had actually gotten pretty far along into designing signs, etc.

He told me that the state eventually killed it because no politicians supported it and there was no strong desire from the public. While I think this is a great idea, I don't have my hopes up.

Apparently the state did a lot of work actually switching over to the metric system (all manuals, standards, etc. were updated to metric) but the plan was eventually aborted in favor of English units and much effort was then spent on switching back. :-/

http://www.dot.ca.gov/hq/oppd/metric1/DD-12-R1_Final.pdf

http://www.dot.ca.gov/hq/oppd/metric1/metricpg.htm

Metric system is way more understandable and easy to mentally manipulate. The only good argument against standardizing it, is people are used to it for many years. But so were my grandparents with our country's currency before we switched to Euro. There's an awkward "bootcamp" period where you just convert every unit to the old one just to get the feeling of the "quantity" but after a couple of months the new units feel normal.

what a coincidence, just yesterday I saw a comedian making fun of UK&US for not using the metric system and instead something he considered archaic

Imperial is very visible in the UK (for road instances and for beer glasses in particular) but the country is pretty much metric now and has been for decades.

I disagree that the UK is metric at all. They try to teach us to think metric in school but in the real world almost everything is still imperial.

We hear imperial units every day in this country. We hear it when we discuss body weight, driving distance, cooking, size of most things, etc.

As a 25-year-old living in the UK, body weight is mostly kilos (that's what my doctor uses, and what I look at at the gym) except when talking to my parents. Cooking is 100% metric; I genuinely do not know what people are talking about when they quote Fahrenheit temperatures. Lengths and weights are metric, though not clothing sizes I guess. Driving distance is the only thing day-to-day where I think in old units.

Doctors and the gym use kilos for body weight, I agree but I don't really hear people ever say "I just dropped a couple of kilograms in the last month" it's always "I've lost half a stone"

I never hear Fahrenheit, which I'm glad about.

Cooking is definitely not 100% metric. The cooking shows on TV still mention cup sizes, pints etc. There's so many recipe books still in imperial and colloquially we never say a 30cm baguette or a 113g burger. It's a foot-long and a quarter pounder.

I'm British. I live in the UK. I'm in my thirties.

I do a person's height in casual conversation (on forms I write it in metres) and driving distance in Imperial measurements (often; I use kilometres when I'm talking to someone I trust to know what a kilometre is, which is generally anyone under about 40). I do depth and altitude in metres, but sometimes I'll use an old chart that has feet (or sometimes fathoms, but that's the really, really old charts). Volume, mass, everything else is metric. I know my mass in kg. I've only the vaguest idea what a "stone" is. A pound? An ounce? Those are twee measurements I sometimes see in old books. I know how much a litre is. I don't even know what the metric unit of volume is. Cubic inches? That seems clumsy even for Imperial units. At the supermarket, the unit used on the fruit, veg and meat is kilogrammes. Last weekend I was comparing pork by cost per kilogramme. Which supermarket do you shop at that uses... I don't even know what you'd use. Not stones, I guess? Pounds and ounces? I remember at about age ten someone telling me the temperature in Fahrenheit, and having no idea whether that was hot or cold. I have less idea today of what it means.

Where this is going is that I thoroughly disagree.

Additional edits, for the fun of it:

"Though I bet you don't go to Asda and ask where you can find 2.272 litres of milk." Fair enough. I do buy milk in pints. If they switched to 2 litre bottles, I'd still buy it, and frankly I'd prefer it if they did. At the moment, I have to look at the scale on the side of the milk marked in litres to see how much I'm pouring into something (because the recipe I'm using specifies litres or millilitres; maybe there's a whole dual-industry for recipes in which you get Imperial units and I get metric; I note that the recipes on the BBC list both units; Jamie Oliver's web page is metric, Delia Smith is both, Hairy Bikers are metric, I've given up looking after those high-ranking four, but I note that not one of them is this Imperial only thing you talked about).

"Do you ever do mile-per-gallon approximations for your fuel economy?" Fair enough. I don't drive so this is a closed book to me.

"Do you ever buy a steak at a nice restaurant?" Yes, often. I have never once specified a mass the steak is to have. That it is marked on the menu in crazy measurements has always seemed a twee restaurant kind of thing; cosmetic rather than meaningful. The meat at the supermarket is, of course, in kg.

"Have you ever played golf or football?" Never golf, and football not since I was about ten. Perhaps we simply move in different circles. You're with the Imperials, I'm with the metrics.

"Where are you?" Deep south. Hampshire. As a drifting aside, I note that London is now approximately 40% non-British born, so that presumably means that about 40% of people living in London have even less grasp of Imperial measurements than I do. Perhaps metric is more common in the south.

Steak update: I am sure I have specified the steak by name, and its name is "Ten ounce" or "Eight ounce" or whatever. It is as meaningful to me as "Medium bowl of custard" or "large bowl of custard", for example. If you gave me a big bucket of sand and asked me to put about ten ounces of sand in a cup, I'd have no idea at all. I seem to recall that I once saw an ounce of butter and it was kind of about "this" big". I'd probably use that as a base.

Ramsay: A ha. Ramsay, of course, is Scottish. Maybe Scotland isn't metric.

I didn't mention buying anything in the shops. I mentioned cooking, as in recipe instructions. Though I bet you don't go to Asda and ask where you can find 2.272 litres of milk.

Do you ever do mile-per-gallon approximations for your fuel economy? Cars are still advertised with mpg values.

Do you ever buy a steak at a nice restaurant?

Have you ever played golf or football?

Points addressed as edits in my post above. For the fun of it.

I'd rather be with the metrics! I'm about to graduate with my design engineering degree, I'm so used to SI units that imperial drives me crazy, but I need to live with it.

Regarding the steak point, do you never ask for the 8oz or 10oz steak?

For curiosity, I'm just outside Glasgow, where are you?

Edit: Gordon Ramsay recipes: http://gordonramsaysrecipes.com/

Butter update: Butter is measured in knobs.

Ramsay, Scottish, he wishes! Might have been born just outside of Paisley but moved to England when he was 5. He's as English as apple pie.

Australian here. I think Australia has managed the metric conversion much better than most of the English speaking world. I found the miles usage for road signs in London odd, as well as the usage for pounds for vegetables in Canada.

Road distances & speeds : kilometres Food measurements are always grams/kilograms & mls and litres ... except for steak & there are some hold hovers like soft drinks which are often in 330ml/600/680ml, 1.25litre, 2 litre. Milk is always litres and not just a straight conversion from ounces to litres, so always 1/2/4 litres. In addition, I think supermarkets are required to list food prices with a price/unit, e.g. $2/kg so that you can easily compare prices between brands/varieties.

Hardware supplies are in metres or dual listed.

Weight is always done in kilograms although older people occasionally will use stones / pounds (which usually requires clarification). Haven't heard them in quite a while.

Engine power is measured in terms of kilowatts. For some odd reason we have an odd unit for fuel efficiency of litres/100km. Not sure who picked this. E.g. 8.5 L /100km.

TVs are sometimes dual although mostly I'll see them in terms of centimetres although computer monitors are still in inches, probably due to the US.

I think when purchasing land it's a bit of mix as you can buy land in hectares as well as acres. There's also squares which I gather is 10ft by 10ft (which is odd and everyone I know silently guesses is around 9.something metres^2).

Not much into sports but pretty sure they use metres there too for Australian Football.

Funny you should mention beer – I've noticed an increasing tendency for pint glasses to be marked "568ml". Milk also doesn't come in pints any more, but does come in 568ml and 1 litre varieties. Still, as a nation we ask for and think of our beer and milk in pints.

The 2 cartons of milk in my fridge right now, say "2272ml 4 pints" on them.

This is because in both the US and the UK, imperial measures are legally defined in metric units. A pint is 568ml, by definition (well, in the UK, the US believes a pint is 454ml, but that's another argument).

The milk is clearly sold in pints though, if they were selling it in litres they would've sold 2 litres, not 2.272 litres.

Ugh US vs UK!

US gallon = 3.79 Litres where as UK gallon = 4.5 Litres

US pint = 473 mL where as UK pint = 568 mL

In Canada beer is sold in 532ml cans and bottles (18fl oz?). It's funny to put imported and local beer cans next to each other, although they look the same, the local is slightly higher.

That's another problem: you can re-label all you want, but the glasses, packings and tins are still the same size. Now if you are confronted with remembering 1 pint or fivehundredsixty... that compilcated other number, you will always opt for the easier one. Weather it's about remembering or mentioning. For the same reason we have more easily rememberable increments of 250ml, 330ml and 500ml.

people order beer in pints in Italy, everyone just thinks a pint is a fancy name for half a liter.

In Franconia you still ask for a "Seidla" which traditionally is 535ml but you get 500ml. In Bavaria you still ask for a "Maß" and you get 1000ml instead of 1069ml.

Measuring metric adoption by counting countries with official adoption is common. Less common is measuring by aggregate PPP-GDP and actual adoption by the public. To approximate actual adoption, I give the US, UK, Canada and Jamaica completely to traditional units and the rest of the world completely to metric.* Using 2011 data from the IMF, I then conclude that traditional units command 31% of usage worldwide.

* These are the countries in red on this table http://en.wikipedia.org/wiki/Metrication#Chronology_and_stat... But a review of the UK article shows that the language "partially complete" is pretty fanciful in describing the current situation in the UK. The story in China is more complex...

Don't we have bigger problems than this right now?

Our schools are so badly mismanaged that we're not even graduating people who can use either standard.

We've got millions of people unemployed who would love to turn a wrench regardless of metric or standard.

(Not to cast aspersions at either party, they are both very nearly equally to blame)

Ironic that a post designed to attempt to rid the world of obfuscation and confusion has a UI that commits the cardinal sin of auto loading the signature list so that it's virtually impossible to get to the footer without letting all the signatures load. :)

Reminds me of getting classes on water conservation in High School only to walk outside of class and see that they are watering the High School's parking lot.

How very often the government evokes the classic hypocritical parent of the old anti-drug campaign commercial of the 1980's where the son finally breaks and yells at his Father "I learned it by watching you Dad!"

http://www.youtube.com/watch?v=Y-Elr5K2Vuo

Everything else aside, can someone explain to me the obsession with fractions (w/out common denominators, even!) in the imperial system?

I love metric, but I have no problem using the imperial system for my work - however, the fact that all objects made for the imperial system are built on fractions makes it impossible to work with. There is no 0.1" there's only 1/8. There is no 0.15", there's only 5/32. etc.

Given the bottom is almost always a power of two (2, 4, 16, 32, and 64 at the most) the conversion isn't hard but there is a definite cognitive overhead to comparing 1/8" vs 5/32" whereas comparing .125" to .15" is an order of magnitude simpler.

Fractional measures are useful when you often have to sub-divide a thing, but you are right in that they make the problem of comparing two things more difficult.

But with that in mind the answer to your question is that when the scales were first devised in the first place that it was apparently more important to be able to evenly split things up easily without grade-school arithmetic than it was to be able to compare a 3/32" socket to a 1/8".

But why not just use /64 or /32 for everything?

3/32" vs 4/32" is win-win compared to 3/32" vs 1/8" or .09375" vs .125"

The stupid answer is that it's easier to add 1/2 and 1/4 than it is 32/64 and 16/64. Keep in mind this is the kind of measurement system that might evolve in the time before most people had a formal education.

Did any of these petitions accomplished anything?

Regionalized units have the same damaging effect to manufacturing as closed software ecosystems has to software development. The only reason most US citizens do not feel the pain of this fragmentation is that they do not have to buy anything that is not adapted to the US market. Again, this is because the US is the biggest market on the planet and thus it is profitable for big companies to adapt their products to US standards.

However, supporting several unit systems is a huge tax on startup companies that work in manufacturing and therefore they reduce innovation and competition, causing harm to everybody along the way.

This is actually an argument, for some people in the U.S., to keep using imperial units. The use of imperial units acts as sort of an "artificial trade barrier" to foreign competition - it's like a tariff that international trade agreements can't touch.

That is a ridiculous argument for a country that is already so heavily reliant on foreign manufacturing. If anything, at this point, the imperial standard is a barrier to having the US become a manufacturing nation once again - because so much industrial technology has been developed without a thought to the archaic measurements.

Maybe it's just me but, while I agree with this, I would like our government to focus on gaining a certain level of basic competence. The last few years seem to have brought to light just how impotent and incapable the US legislature is.

The other two branches seem to be doing fine, but I'd like to focus our attention on perhaps changing this ridiculous farce into something that might work, just a little bit.

The big problem is that due to our system of govt any change will be brought of the back of legislation, which, unfortunately, will have to pass thru the broken and disfigured legislature.

That said, I hope this petition succeeds :)

The US use of imperial units definitely requires a good bit of annoying overhead - owning two sets of socket wrenches and hex keys and never knwowing which one a manufacturer has used is just the first such inconvenience that comes to mind. So I agree that it's well past time to complete the switch.

That said, I will miss imperial units if they go. There's a natural poetry to them that metric lacks. Imperial units seem to embody and communicate their own history - history of path-dependence and weird math, to be sure - while metric units seem too perfectly consistent, and therefore somehow sterile.

I don't see this ever happening. There just isn't a push from within to do it.

I grew up with the metric system but have now come to largely accept the imperial system as a more humane system.

Nassim Taleb actually talks about the benefits of it in his latest book Anti-Fragile as well.

The metric system is already used for anything important in the US and doesn't need to be further legislated. Look at any food item you buy in the supermarket it already has grams or ml on it.

I wrote a piece a few years ago about this: http://stakeventures.com/articles/2007/08/28/in-defence-of-i...

I remember being at a 1971 conference in London, when a Brit asked a member of our party "When will the US go metric?"

My buddy quipped without hesitation, "As soon as you Brits learn to drive on the right side of the road!"

I don't think politicians would ever allow this, especially during these times, since the proposed change would cost millions in change of signs and anything where the imperial system is used.

You would save that pretty easily in not having to write separate software/everything for the US and for the rest of the world. Not to mention things like http://articles.cnn.com/1999-09-30/tech/9909_30_mars.metric....

Not the first time it's been tried: http://en.wikipedia.org/wiki/Metrication_in_the_United_State...

There were still some kilometer markers on the roads in Alabama when I moved there in 1997. Apparently, the state spent $3.2 million to put up km markers and signs in addition to the mile markers and signs. This proved to be too confusing, and they were all taken down. Most the people I knew didn't miss them.

http://news.google.com/newspapers?nid=1842&dat=19971128&...

I lived in Alabama for a while back in the metric days. The article you link to seems to confirm the general impression I had of how it went down. US: "We're switching to the metric system, everybody!" Alabama: "Yay! Switching to metric!" Alabama: "Okay guys, we've got all our new metric highway signs up, how's everyone else doing with theirs?" (crickets chirping)

I personally thought the kilometer signs were pretty cool. The person's comment about the metric initiative being hard to defend when none of the other states followed through seems to ring true -- it's easy to see how the public might have thought they had been talked into a boondoggle.

Another petition which may be more effecitve would be directed at the more rational/scientifically minded people at Google (in as much as they don't have Rick Santorum on their pay roll) to rename nexus 4/7/10 to be in terms of metric units not inches. That would may lead to a very rapid comfort with metric sizes for a large and influential chunk of the population.

This would also avoid the potentially unpleasant comparison to those who hope to eradicate Spanish by demand English be the state language.

Interesting war story around Imperial to Metric conversion errors.

Relevant to the discussion...

http://en.wikipedia.org/wiki/Gimli_Glider

One thing I never see mentioned is the awkwardness of the metric names. The older measurements are all one syllable, while their metric replacements are often three or four.

mile -> kilometer inch -> centimeter pound -> kilogram

The only one that comes out even is ounce -> gram.

Obviously it's not a huge impediment since many other countries got past it, but I'm sure it just adds to the discomfort people have with it.

>The only one that comes out even is ounce -> gram.

Gallon -> liter?

And most of the extra syllables are because SI uses prefixes, instead of inventing completely different units. I think the verbosity is justified by enhanced understandability.

The real cost is in manufacturing and maintenance.

What is the cost of replacing every machine, every factory, every load tolerance specified in every standard? Every screw, every nut.

Things that need to work, in place for decades, which we can't arbitrarily take down. Power plants, water filtration systems. How would you roll it out?

It's because the US is so large and industrialized that makes it expensive.

One argument some people make against switching away from imperial units - it acts as sort of an artificial trade barrier for foreign competition. It costs non-domestic manufacturers more to package their products for distribution in the United States, making it sort of a "tariff" for foreign goods that international trade agreements can't touch.

But it works both ways. It is a "tariff" when you want to export.

I didn't claim the argument made sense. :)

I've Given up.

BUT, the metric system in the US has ben usurped by base 10 US units. As a civil engineer the measuring tape was in feet and "tenths of feet". A "mil" is a thousandth of an inch. I worked for the US government civil engineers in the 1990's. They were going to issue contracts in metric years ago. I don't think they ever did.

related question to people from the US: did you actually learn the metric system in primary school? did you learn it besides the imperial units? I believe as Tloewald pointed out that the adoption really depends on whether people are learning it and not what politicians declare to be the standard.

You learn it, but academically. Growing up with everything in feet, miles, pounds, etc... you get a feel for whether to put on a sweater if it's supposed to be 60 degrees out or not, or how long it might take to drive 10 miles on the freeway, or about how far 20 feet is. So even for someone like myself who has lived in Europe for a long time, metric units don't feel quite as 'native' or ingrained, except for temperatures, because you deal with those every day.

Yep, learned metric as well as imperial, and how to convert between the two. Primary school was ~20 years ago for me.

High school science was all in SI, of course.

I can't remember if it was primary school or high school, but I learned it. It was not beside the imperial units. Those were learned first (and very early) while metric was taught as a part of science classes.

You learn it, but you don't use it practically outside the classroom. So the units don't get ingrained in your thinking. You really need to use the units for cooking, for personal measurements like height and weight, for driving, for weather, to really get used to them.

This is fantastic!! They told me in 2nd grade (1968) that the metric systems was coming in 4 years and we had to learn it. This is great news. Finally I will be able to use those metric socket wrenches I bought. Oh, wait I already do.

Just a note: Brazil adopts the metric system, but we measure diameters in inches and land in acres.

Adopting the metric system doesn't mean getting rid of non-metric units, some things just make sense to measure in units that follow human scale.

The tech industry has to take the lead by renaming their products: MacBook Pro 33cm, Nexus 18. Using inch for display is a worldwide standard, not just US. It would be strange to look for a 35.5cm notebook or a 100cm HDTV.

Maybe in the US. People from other countries want a TV with a diagonal of one meter. It even sounds better because 1 meter is like a barrier unlike 40 inches which is just a number.

So we'd have to rename the quarter-pounder with cheese to royale with cheese?

The Metric system would probably be ubiquitous in the US by now if Ronald Reagan had not disbanded the U.S. Metric Board in 1982 and overturned laws encouraging schools to teach kids the metric system.

A bit of helpful contrarianism about how Metric isn't always best:

Dan Bently, "Metric Doesn't Work", OSCON 2012

http://www.youtube.com/watch?v=XdK-Cr1pe30

I'll just leave this here.

http://www.theonion.com/articles/metric-system-thriving-in-n...

While we are at it, why not standardize:

* date and time formats

* language

* time zones

* currency

Seems about as easy and has the same kind of benefits.

> Why not standardise ... date and time formats

There are two ways to do dates and times (especially when sending machine-readable data across the web):

1) ISO 8601

2) A world of pain.

Personally, I prefer option 1. So, that one is done.

The "world of pain" with US/UK date formats is that code that's not even written yet can fail to interoperate, but only when it's deployed to a different machine with different system defaults and only after the 13th of the month rolls around. That kind of landmine is an unacceptable feature for a format to have.

It seems to me that time zones are standard.

http://en.wikipedia.org/wiki/Standard_time

For the most part, although daylight-saving time rules are very non-standard even from year to year.

OMG, I actually learned the metric system in public school in the 1970s. Then Reagan got elected and canceled it.

Now American kids have to get into drugs to learn the metric system.

Why not start a bit of a geek pro metric movement to raise awareness on the issue. I could imagine some funny Tee's and stickers if nothing else.

The metric system? Pff! Sign this petition instead: http://wh.gov/UNMa

One sure way to get metric passed in the US: tell all the 220-lb ladies that their weight will drop to 100kg.

Never happen. The crazy right-wingers will see it as a another "sign" of the UN trying to take over the US.

Please do this.

Regards, The rest of the World.

http://wh.gov/UQye

Help stop the metric system!

Well, you can make a change too. Don't use products that are not in metric.

Why do they have to make this page look like propaganda?

US uses US standard measures, not imperial.

Yep. It's long time overdue.

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