I am not anti-metric by any means, but having done carpentry a lot in the past it always strikes me when this comes up that one of the central arguments for (a limited use-case of) the imperial system is usually glossed over: the fact that in many crafts (especially historically), using base-12 makes certain things much easier. It divides into 3rds far more easily, divides into 4ths slightly more easily, and still divides into 5ths with only one digit after the decimal.
Just like computer programmers have no problem immediately recognizing that 256 is 2^8, it became intuitive when working with the Imperial system (at limited scales) that 48 inches is the same as 4-feet but that it is also 3-stud-distances long (studs in walls are often placed 16 inches apart).
Even if you don't work in crafts where dividing things by 3 is more frequent than dividing by 5 it is easy to imagine how certain things might be more difficult if we used base-10 for time (as, it has been pointed out, has been attempted)- and thereby using the ability to easily divide an hour into 3 parts (for example).
Consistent base-10 and international standardization has advantages that far outweigh these minor things- but I think it's important to recognize that there is, surprise, a rational practical reason for sticking in some cases to Imperial units- it's not purely tradition or politics or their "organic-ness" (anymore).
My house is 100 years old, and having some construction experience myself I take care of small maintenance issues. I'm European but I grew up with both imperial and metric systems side-by-side, so it was easy for me to pick up American standards on things like stud distances and so on. It is convenient to have some things like that standardized, although the particular standardized measures themselves are highly arbitrary.
However, because my house is old nothing is perfectly standard any more - all the angles are off by a degree or two, different parts of the house have slightly stretched or compressed over the course of a century, and so on. So whenever I measure something I end up noting both metric and imperial - imperial because I am going to be forced to deal with it at the store/supply depot, metric because I want to get the numbers right and I would way rather work in base 10 that mirrors my 10 fingers than juggling fractions of an inch (a unit which is divided into 16ths instead of 12ths because...er...um...).
Unfortunately, I don't expect this change any time soon.
> 48 inches is the same as 4-feet but that it is also 3-stud-distances long (studs in walls are often placed 16 inches apart).
To some extent that's an artifact of the units we use. We could just as easily put studs 40cm apart, which is approximately the same distance, or 50cm (0.5m) apart, which would be particularly convenient.
From Wikipedia: "In the United States [...] typically placed 16 inches (406 mm) from each other's center, but sometimes also at 12 inches (305 mm) or 24 inches (610 mm)." (https://en.wikipedia.org/wiki/Wall_stud)
A quick search suggests that 400mm is common in metric-using countries.
It was 50x100 when I was building in Chch ~10 years ago.
It was explained to me that the rough cut timber was closer to the stated size, and that the finished timber we used for framing was named after the unfinished dimensions. Of course, I don't know how true that actually is.
Certainly the unfinished 75x50 we used for roofing purlins (spelling?) was noticeably thicker than the finished structural 100x50s
When dealing with fractions, twelve is more efficient. I agree imperial units still aren't worth the trouble of being different than the rest of the world.
You shall count only the prime ones, both have only 2 prime divisors.
Then 60 would be of real use (and it has been used in the past[1]... and still is in angular measurements with the famous 360 degrees) but it contains only 5 as extra prime divisor.
Carpentry is a bad example... 1/4 inch vs 6mm or 7mm doesn't make any difference in this low precision craft... it is far from being precise to the millimeter... Even if you were doing higher precision wood working, you could make your box-joint 6mm wide instead of 1/4" and it would still be a perfect fit.... Also, try dividing an inch into tenths using a ruler?
In fields where precision does matter - such as machining or PCB design - decimal inches are used. Calipers work in decimal inches and steel rules are often marked in tenths. PCB layout programs typically allow you to use either millimeters or mils.
Give 240cm or 360cm a name (like STL for "standard-timber-length", 1 stl = 240 cm) and you're effectively doing the exact same thing as the imperial system. Then it's just a popularity contest (which is fine and appropriate and metric wins except for wrt time) but at least conceding the fact that base-10 scaling of units is not intrinsically superior for all units & situations.
Edit: If the argument is that metric is more intuitive (less memorization because of consistent scales) then I think that's a great argument. If the argument is that it's more standardized and more widely adopted, I think that's also a great argument. But I think that the argument that the metric-system is somehow superior intrinsically because only scales of powers of 10 are worth naming (as the name implies) is a poor argument, as you've helped illustrate.
You're claiming that the ability to divide evenly is an intrinsic quality of Imperial, and then when I point out that actually it can be done in any measurement system (including metric), you claim that this makes metric like Imperial, because...well, because dividing evenly is a property of Imperial.
Unless you're suggesting that timber should only be available by 1 inch, 1 foot and 1 yard measurements in the US and by 1 cm, 1 meter, ermm...I kilometer(?) in other countries?
Edit: I didn't claim metric was better at all (it is, but I didn't claim it!). You claimed that Imperial was better for dividing up lengths of timber. I explained why it wasn't.
I guess the real issue is which units get names. Yes, you can do with 12cm exactly what you can do with 12in- but the latter gets its own named unit. The Imperial system has a preference for scaling its units by some slightly more practical number of sub-units- 12, 60, etc. I can imagine someone saying, for example, "why name 1000 centimeters as another unit? Can't I say 'thousands' using the same number of syllables? What's worth naming a different unit is 240cm since that's used a lot with timber..."
Someone strictly advocating the metric system would say "that's the point, kilo is another way of saying 1000 no matter where you live in the world or what you're measuring. Feel free to call 240cm a 'frob' if you like, but please, only do so in private- don't order 14 frobs of lumber, order 33.6 meters." (edit: which is a perfectly valid point. It's the slow accumulation of frobs that made the imperial system untenable. We trade a little bit of efficiency at a local level for greater global efficiency when we adopt metric.)
Actually, I can remember at least one commonly used alternative name from my time in a German-speaking country. The term "Pfund" (literally, pound) was frequently used to refer to a half-kilogram. I remember it being particularly used in reference to a loaf of bread, by both bakers and customers. (That was a long time ago, don't know if it's still common.)
There's really only one unit for length: the meter. Centimeters aren't a different unit, they're "hundredths of a meter".
You can call your lengths of timber "frobs" if you want, even in public! You could have people order them that way and sell them that way. The only requirement most places have is that you also specify what that is in meters so that people who don't know what a frob is, know what they're buying.
It just makes sense that your frobs should be a useful number of meters so that they can be divided or handled easily and don't require 15 decimal places to express.
Edit: I have a question for you: would you support changing your currency away from 100 cents to the Dollar to something like the old Pound with 240 pennies to the Pound?
After all, if you're talking about measurements everyone uses and need to divide up, it's far more commonly required for cash in people's everyday lives than length or volume or anything else!
Seriously though good question. First though it made me realize that you never see prices in thirds of a dollar- as if everyone avoids it and have simply gotten used to avoiding it. I can't imagine a situation where ease of dividing by three for money actually adds any efficiency. Similarly, while I do see the value in dividing the day into 24 hours, I certainly wouldn't advocate a unit that's defined as one 60th of a second (even though it has even more prime factors than 12 ;)
I concede that the use-cases where having more prime factors and therefore easy non-decimal division are few and far between. I guess what surprised me when doing construction was that there was a very rational reason for a foot being 12 inches rather than 10- that it's not simply a relic of the fact that a human foot seems to be about 12 thumbs long- some arbitrary number accidentally ingrained in some cultures. And as illustrated by the fact that stocks were eventually decimalized and then made to trade at penny-granularity, computers and the fact that we don't do a lot of division in our heads or on paper anymore will probably eventually erase most remaining efficiencies.
> I certainly wouldn't advocate a unit that's defined as one 60th of a second
Veering sharply offtopic, seconds are actually called seconds because they're "second order minutes". So, just as a minute is 1/60 of an hour, a second-order minute is 1/60 of 1/60 of an hour.
In the past, people have indeed used "thirds" (1/60 of a second) and in the 13th century, Roger Bacon went as far as using "fourths" (1/3600 of a second)!
I actually would support changing the divisions of the dollar to a non-base-ten standard. Specifically I would make it dollars and quarters and dispense with anything smaller. We used to have a half-penny coin. We got rid of it when a penny was the same value as a quarter today.
You miss the base-10 point: you can switch in zero time from 240cm to 2.4m and vice-versa, as you can switch in zero time from $2,40 to ¢240 when you expect ¢60 in return.
And you can totallyignore the "2", and focus on the "40" part, if you care about the precision, in zero time, and switch back to a global view.
The real problem then is our counting system. If base-12 is the most convenient, then we could count in base 12 too. That, however, is clearly never going to happen, so we are stuck with the less efficient base 10 system.
The other thing is that if everything is in powers of 10, then complex calculations are done that require multiple units, it's much easier to calculate. You don't need to keep a dictionary of 'conversion factors' to have these complex calculations make sense.
Not one of the downvoters, but working in (hundreds of) centimetres (240cm) as opposed to meters (2.4m) is not as crazy as it sounds. Tape measures or carpenter's rulers will have centimetres on them all the way.
Also, people consider it a matter of precision. If I ask for a piece of wood that's 2.4m long, I am probably less concerned with the precise length than if I ask for one that's 2400mm long.
What? The precision of $2.40 and 240 cent is exactly the same. Two significant digits.
It's kinda funny, every time this debate comes around, I see that the people advocating imperial are always confused by the concept of precision, which is handled very naturally in the metric system, but people advocating metric are confused about the way the imperial system uses subdivision.
For a metric person, a measurement such as 13/64" looks weird, and for an imperial person, a measurement such as 5.2mm looks weird, when in reality they are very close, and of the same precision.
They're usually referred to as 2.4m and 3.6m if that makes it easier for you to track. I converted them to cm as I thought that would be simpler for people.
(replying to the wish for a name for 2.4m; edited out): Why for the 2.4m, but not the 1.8m or the 3.6m? Surely it makes just as much sense to refer to it as the "two point four" as anything else?
A piece of 2" x 4" timber is still referred to as "2 by 4" in the UK, except it now measures 50mm x 100mm (actual conversion is 50.8mm x 101.6mm, the difference being moot when building scale is taken into account)
Perhaps not to you, but most folk I know (in the UK) aren't quite so hung up about it. I'll sometimes refer to a half-liter as a pint, or a liter as a "couple of pints", or a meter as a yard.
Though the pint is by far the stupidest unit. Why on earth wasn't it standardised at 500ml? It would have fixed pints, quarts and gallons all in one go!
I know, you can think up immediate objections, but having 568ml to the pint and 4.546 litres to the gallon, is just wrong!
Nah, I just couldn't picture anyone doing woodwork in hundreds or thousands of units (now, where did I get that idea...?), or dividing base 10 units. Since it sounds like wood is sold and worked in base 12, I'd use metric no problem. But that makes the difference between imperial and metric pretty arbitrary, doesn't it?
I've actually worked in the construction industry in New Zealand, which was thoroughly metric when I was building houses ~10 years ago.
And we did everything in mm, standardised timber was "100x50" - mm was assumed, which was close to 2x4 Inches.
(Actually, I think the finished standardised timber is smaller than 100mmx50mm, but for some reason was still called 100x50)
sheets of Gib plaster (Drywall?) were 1200x3600,(possibly 1600x.. I don't remember) sometimes bigger. rooms had 2400mm or 3600mm stud heights.
90mm nails were used to assemble the house frames, and 50mm nails were used when the 90mm nails would have been excessive.
We only really used Meters when we were being vague - "Go about a meter further out!" and usually converted to mm when we were actually cutting or fastening something. I never poured any concrete myself, but I'm pretty sure the foundation boxing would have been measured out to the mm, even over 10s of meters of distance.
If I ever gave someone a measurement in cm I'd get told "Only Dressmakers user centimeters!" I don't think I ever used feet, and I only ever used inches when discussing lumber, and would always be told to use metric.
I strongly disagree. Using the right tool for the right job is worth far more than enforcing arbitrary universal consistency. In a math course, you'd measure angles in radians so you're dealing with nice small multiples of pi. I think it'd be downright dangerous to use radians in a fighter jet, say, when the precision you need is much better provided by degrees.
Imagine if we enforced only one programming paradigm, since they're all equivalent. Or if we demanded that logicians and cs professors only prove things using turing machines, instead of picking the model of computation that best suits the problem. If there's a case where the english measurement system is more convenient, people should use it.
You just get used to whatever units you're working in. If you'd been trained in radians when learning how to fly, everything would be fine. It would be funny though to hear ATC clear someone to land on runway pi/2. That's probably not as succinct as runway 9, but people would be used to it if they learned it in their primary training.
The real problem though is switching costs. There are tens of thousands of planes out there and more than a million pilots. To switch all of the compasses, GPSs, flight computers, heading indicators, etc. as well as retrain a metric pantload of pilots would be ludicrous for no appreciable gain.
Don't get me wrong though. I love the metric system and think it's great, however first and foremost we are creatures of practicality. If US dominance in the world slips over the next few generations, I would imagine it will at some point join the rest of the world and abandon imperial measurements.
>Using the right tool for the right job is worth far more than enforcing arbitrary universal consistency.
Except units of measure are not "tools"...they are ways of communicating information. And when each person feels the need to enforce their own version of "right tool for right job" then things like the mars orbiter incident happen.
>Imagine if we enforced only one programming paradigm, since they're all equivalent.
Hardly. A better analogy would be to enforce identical calling parameters for DLLs libraries across all languages. That would benefit all languages and improve interoperability.
>units of measure are not "tools"...they are ways of communicating information.
How you communicate information is important and has real impacts. Given a graph, you could choose to encode it as an adjacency matrix or as a collection of adjacency lists. Both convey the same information, but nobody would say we should pick one and only one. I disagree with the assertion that measurement units aren't tools or that they are exempt from similar consideration.
Sure, the Mars incident is a call for consistency, but it's a call for consistency inside NASA. That shouldn't affect carpenters who need divisibility by 2, 3 and 4 more than they need 5. Or those who like to use inches because theyre significantly larger than centimeters and consequently easier to approximate by eye.
>Sure, the Mars incident is a call for consistency, but it's a call for consistency inside NASA.
No its not. Realistically space travel is going to be a humanity as a whole deal, not "inside NASA". Remember that the USA is like 4% of the world population. Even if the US contributes 10x more than everyone else per person that still puts the US in the minority. Consistency here is not a "nice to have"...its mission critical.
>That shouldn't affect carpenters
So you propose teaching your future carpenters and space engineers different units of measure?
>approximate by eye.
Approximate by eye? Seriously? Intel is aiming at 10 nanometers. Nobody is eyeballing anything in the modern world. Note...nanometers not nanofeet...this from an American company.
> No its not. Realistically space travel is going to be a humanity as a whole deal, not "inside NASA".
I think it's a fair bet that when spaceflight becomes widespread and commonplace, we're going to have many discrete groups of people developing, producing, operating, and maintaining their own particular spacecraft independently of each other, and not "humanity as a whole", as a singular undifferentiated mass, working on a single uniform spaceflight project.
Consistency within a specific project is clearly necessary; uniformity among distinct projects is, speaking at the macro level, a liability. Variation is an evolutionary advantage; artificial uniformity slows progress.
> So you propose teaching your future carpenters and space engineers different units of measure?
Why would this even be a question? Should programmers only be familiar with one single programming language? Should people in general only ever learn to speak a single verbal language? Is there ever an advantage to only being familiar with a single set of tools, and ignorant of all others?
> Nobody is eyeballing anything in the modern world.
Most people are eyeballing most things in the modern world. It's only in the case of activities on the scale of building spaceships and 10-nm-process integrated circuits that people require the level of precision that you're talking about. The vast majority of human activity remains outside of these domains.
The original article was about American resistance to adopting metric units as a default practice in day-to-day life, and not about the use of the metric system by people engaged in highly specialized disciplines. It'd be a bit absurd to suggest that the measuring units selected for high-precision work by the small set of people currently working on microprocessor design are necessarily the optimal ones for e.g. baking a cake or tiling your bathroom. In the latter use cases, one could make a very compelling case that units optimized for alignment with intuition are vastly more useful than ones optimized for micro-scale precision.
>Consistency within a specific project is clearly necessary
I'll concede that it only matters within a project...but projects invariably consist of many people and each of them "think" in their unit of measure. Sure you can mix them and hope they remember to "think" in metric at 1AM when pushing for a deadline, but really...
>Is there ever an advantage to only being familiar with a single set of tools
Thats the thing. These are not tools. They are units of measure. Aside from the odd instance where its easier to divide by X all you're gaining from using many units of measure is chaos.
>Most people are eyeballing most things in the modern world.
Definitely. Eyeballing happens regardless of unit of measure. And usually when someone is eyeballing it its not life/death.
>It'd be a bit absurd to suggest that the measuring units selected for high-precision work by the small set of people currently working on microprocessor design are necessarily the optimal ones for
Absurd indeed, but not what I was getting at. Units of measure is something thats internalized from a high-school age. So unless you have a way of splitting the kids between space engineers and carpenters at that age then why tech imperial? And even if you could split them, the mix of units of measures employed nationally would be much worse than randomly picking one.
I get that Americans are attached to imperial...its just very difficult for everyone else to under why given this: http://i.imgur.com/YJzhkZl.jpg
> but projects invariably consist of many people and each of them "think" in their unit of measure.
Obviously, you'd assemble project teams who are familiar with the tools, techniques, and conventions that you intend to use with your project.
> Sure you can mix them and hope they remember to "think" in metric at 1AM when pushing for a deadline, but really...
And the Chinese engineer who's working on a project where all of the documentation is in English might slip up when he's punchy at 1 AM and accidentally complete some of his work in Chinese.
This is a good argument for making sure that team members are well-rested and alert while doing their work. It's also a good argument for scheduling work reviews, proofreading, and time for correcting errors in the project plan. It's not at all an argument for abolishing the Chinese language.
> Thats the thing. These are not tools. They are units of measure.
Units of measures are tools. Tools are devices, whether physical or conceptual, that we use to extend our capacities for interacting with the world. In this case, since human beings do not natively have the capacity to quantify continuities, we apply the tool of measuring units to break continuities down into discretely countable chunks.
And, like all tools, how well they work depends on what goals you're trying to accomplish, and in what order of priority, in a given set of circumstances. Metric units are great in a limited set of contexts in which uniformity of post-hoc representation is more important than practicality in the activity of measurement itself; but this means that they are, for the same reason, less effective than customary units for the vast majority of situations that involve measurement.
> Definitely. Eyeballing happens regardless of unit of measure. And usually when someone is eyeballing it its not life/death.
Very few situations are matters of life and death, and in those rare circumstances that are, people will naturally be cautious and rigorous in their methods: I'd expect people to use precise measuring instruments, and to perform measurements multiple times, so in such a situation, questions of familiarity with particular units are scarcely relevant. When you're relying on the precision of instruments, the actual measuring units you're using are less important: metric, imperial, or otherwise, they'll all work just as well.
> Units of measure is something thats internalized from a high-school age
I don't know how much anyone "internalizes" any measuring units, but to the extent that they familiarize themselves with theDefinitely. Eyeballing happens regardless of unit of measure. And usually when someone is eyeballing it its not life/death.m, there's certainly no cause to familiarize oneself with only one set, at the exclusion of another.
> So unless you have a way of splitting the kids between space engineers and carpenters at that age then why tech imperial?
How about we keep doing things the way we are - teaching everyone both sets of units - and letting them determine for themselves which ones are most useful to them for each particular application?
> I get that Americans are attached to imperial...its just very difficult for everyone else to under why given this: http://i.imgur.com/YJzhkZl.jpg
All that graphic demonstrates to me is that while, with imperial/customary measures, there are a variety of separate base units to choose from, each appropriate to a particular scale of operation, the metric system only offers one base unit, and pretends that applying a 10^x coefficient to that single base unit somehow makes it a different unit.
That's what you're not getting: feet, yards, inches, etc. are fundamentally distinct units that have been tweaked to relate to each other, where necessary, by factors that are often much more convenient than 10. But you're just as capable with customary units as with metric of sticking with a single unit and applying scaling factors: I can just as easily say e.g. 24.2 x 10^4 feet as 45.83 miles.
I can even use metric prefixes if I'm so inclined, and say 24.2 kilofeet! Or 2.9 megainches! All the same value. But using these prefixes is just a bizarre re-implementation of scientific notation: in what way does it make sense to encode quantitative information as a verbal prefix appended to the name of the thing you're counting, instead of just using numbers?
Wow, I would not have believed someone would make the argument that everyone needs to use metric because some day we'll all be in space until I read it. Thanks for broadening my horizons.
Degrees are no more precise than radians. If you're a human you use a certain number of digits and they both work. If you're a computer using integers you're far too imprecise either way. If you're a computer using floats they are equally precise. If you're a computer using fixed point you're better off with something like 2^32ths of a circle.
Wood is an easily workable, relatively inexpensive, and, importantly, renewable resource. We'll be seeing more of 3D printing for sure, but you're kidding yourself if you think it'll replace carpentry.
I want a 3d printer / wood router hybrid. All I've managed to do so far is a 3d printer / laser cutter hybrid, but it takes forever for it to cut wood.
"Even the car's name tag positioned on the rear bumper, is carved in a 24 hour process from a solid block of aluminium. It is the Pagani way of reassuring its customers that their cars are built to their own standards exceeding the highest in the industry."
Great example really. Basically highlighting my message; it can be done (and can be awesome- machined parts are top-quality) but the Huayra costs $1.3M.
I would love to hear from someone who does carpentry (or some craft-like equivalent) with the metric system- specifically what kind of ruler/tape they use and whether it has a special 1/3 and 2/3 mark on it (since you don't want to have to eyeball 0.33333....) or if they just avoid dividing things by three altogether.
Because the truth is, your perspective is a political one more than a practical one. The whole idea of "officially" adopting either system is somewhat misleading- regardless of politicians or zealots decide, most craftspeople would use rules that easily divide into three, most programmers would often reference things in terms of base-2, and most people would still prefer 24 hours in a day. There is no general-case optimal winner that applies to all measurement and work-flow situations.
In the case of base-2, international bodies have already found a nice dual-system ( http://physics.nist.gov/cuu/Units/binary.html ). A simple solution for (for example) carpentry that would give the best of both worlds would be to define a unit that is exactly 1/60th of a meter. Let's call it a "sixer." Now someone crafting things can have all the convenience and easy division they need (here- cut this at 1/5 of 1/3 of a meter- no problem!) and still have it unified with the meter at some scale. There would be issues- but it's situational, which is my point.
You know, there's about 25 millimeters to the inch, and I've never seen anyone measure anything with more than 16th-inch precision for any construction job - maybe for very high-end cabinetmaking people use 32nds, but generally millimeters will give you more precision than you need, certainly if you're using a carpenter's pencil, which makes marks thicker than the smallest scale on a ruler.
I have no problem dividing things by 3 in metric. Rounding up to the next millimeter is going to result in an error equivalent to a couple of human hairs. If I'm working with wood and I need a perfect fit I'm going to be using sandpaper long before that.
Seriously, do you imagine that construction workers and craftsmen in Europe, Japan and the rest of the world spend their days ina state of helpless anxiety because of their inability to divide things with sufficient precision, or do you think they just get on with it and make buildings and furniture as good as any you can find in the US? The construction industry didn't collapse in the UK, Ireland, or Australia when they adopted the metric system.
No, I assumed they had a very good way of doing it, which is why I asked about it :-) It was a sincere request for comment but it obviously came off as a cynical challenge, which wasn't my intention.
> I would love to hear from someone who does carpentry (or some craft-like equivalent) with the metric system- specifically what kind of ruler/tape they use and whether it has a special 1/3 and 2/3 mark on it (since you don't want to have to eyeball 0.33333....) or if they just avoid dividing things by three altogether.
I would love to hear from someone that uses the imperial system how they determine exactly 1/3 of 10 inches and how they eyeball 1/3 of 5/6 of an inch.... My point is it is easy to find measurement scenarios that would make life a little harder for either system. 12cm (metric) for example is trivial to divide into 1/3, 2/3, 1/2, 1/4, 1/6 etc etc. 4.72 inches (imperial equivalent of 12cm) would be harder to do.
Besides there are very easy geometric methods to divide a line exactly into any number of equal parts, even if you do not know its actual length precisely.
I've done a bit of carpentry around my house. Since I live in Sweden I always use the metric system.
For me the focus on division by three is a bit strange. Sure I sometimes need to divide by three, but I also need to divide by five, or two or seven. I guess the thing is that our building standards are expressed in the metric system, so it makes sense thinking about them in terms of meters or centimeters. US building standards are expressed in the imperial system, so it makes sense to think about them in feet and inches.
Why would I want a unit that's 1/60th of a meter when I have a perfect 1/100th of a meter? A third of a meter is 33.3cm, working with wood you don't need more precision than that, if the decimal sign makes it difficult to do calculations, just step it up to 333mm.
I'm not a carpenter by trade but I guess that a professional carpenter here learns quite well how to divide by three even in metric. I see this argument popup every time there's a discussion about using the metric system in the US and I find it weak. For me this argument only sounds like "but it's hard to learn something new".
I'm sure there are pros and cons with both the metric and the imperial system, but in the globalized world we live in, the fact that The Rest Of The World uses the metric system should be a pretty convincing argument to use it in the US as well. I mean after all, The Rest Of The World has accepted English (in one form or the other) as the Lingua Franca in order to make communication across borders easier. You don't see us whine about stuff like "but in Swedish I can much more succinctly express that it's my paternal or maternal grandparent I'm talking about, so I don't want to use English".
Point taken, and I acknowledged in my first comment that it was a weak reason compared to the reasons for adopting. It wasn't meant as advocacy :-)
I would point out however that no one (that I know of) claims that English is the most popular because it is intrinsically the most efficient for all situations- i.e., on its merits as an efficient language rather than geopolitical factors. I definitely think that there are certain situations where communicating using non-English would be (locally) optimal- even if the parties communicating were fluent in English. Even as a native English speaker I truly wish English had the equivalent of the Tagalog particle "daw/raw," for example ( http://tagaloglang.com/Tagalog-English-Dictionary/English-Tr... ), or the fact that Cantonese can often communicate the same information as English using far fewer syllables...
In other words, I'm perfectly fine saying that using English is globally optimal (and convenient for me) because of its adoption, while still being perfectly happy knowing that some languages have attributes that make them more efficient, if you know them, in certain circumstances. I don't pretend ex-facto that English got this way because it is a truly superior solution in all circumstances if only everyone knew it. Nor do I feel like English's status as a (quasi)-standard is threatened by someone pointing out that Swedish would be more efficient in some settings (say, family history) even if everyone did know English. I would say "cool."
Defining units in terms of other units via something other than base-10 scaling in order to have more integer factors than 2 and 5- in some cases trading the 5 for 3 and 4- can be advantageous. That's all I'm saying, nothing more or less :-)
When i was building stuff out of timber i would typically only work in mm (or metres for longer lengths (timber is sold in full lenths of 6 metres or shorter bits at various lengths (at least in .au)) and don't need any further precision.
a 334 mm length will quite happily go in a 333mm gap. though again i'm not a professional carpenter i just worked with my father a lot.
Just like computer programmers have no problem immediately recognizing that 256 is 2^8, it became intuitive when working with the Imperial system (at limited scales) that 48 inches is the same as 4-feet but that it is also 3-stud-distances long (studs in walls are often placed 16 inches apart).
Even if you don't work in crafts where dividing things by 3 is more frequent than dividing by 5 it is easy to imagine how certain things might be more difficult if we used base-10 for time (as, it has been pointed out, has been attempted)- and thereby using the ability to easily divide an hour into 3 parts (for example).
Consistent base-10 and international standardization has advantages that far outweigh these minor things- but I think it's important to recognize that there is, surprise, a rational practical reason for sticking in some cases to Imperial units- it's not purely tradition or politics or their "organic-ness" (anymore).