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.

Canada suffered through a problem similar to this when it went metric, and ended up with the Gimli Glider. http://en.wikipedia.org/wiki/Gimli_Glider

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.

"A foolish consistency is the hobgoblin of little minds, adored by little statesmen and philosophers and divines." - Ralph Waldo Emerson

>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.

>more of 3D printing for sure, but you're kidding yourself if you think it'll replace carpentry.

I wasn't suggesting that 3d printing will 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.

Also, wood is beautiful.

The present is full of CNC machines, and yet cars are not milled out of billet aluminum.

It's rarely worthwhile to fabricate something, when you can readily produce it from bulk forms like lumber or bar stock.

With the awesome exception of the Pagani Huayra:

http://www.pagani.com/huayra/partners/aspa.aspx

"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.