# Talk:Metric system

## Contents

## American workers unreliable due to lack of metric?[edit]

So the paragraph that talks about "Americans have an overall poor grasp of measurement" seems a bit problematic to me. I'm all for giving a bit of crap to the United Statesians for their refusal to get on the metric bus, but part of this paragraph seems like a general statement of fact that is basically sourced from some guy's anecdote about one company he worked at. The claim that "Americans are considered unreliable in working with metric units...resulting in more jobs going to [other countries]" seems out of proportion to the quality of the source.

Am I wrong about this? I'm new here so not going to make an edit on something like that without consensus on the talk page, but it seems like that statement should be changed if it doesn't have stronger backing. Gringodemaio (talk) 15:30, 23 January 2018 (UTC)

- @Gringodemaio, I believe this statement was intended to be humoristic (but quite clumsy, indeed). The source [8] looks like a personal point of view that lacks of supportive documentation and therefore not to be trusted. In the other hand, the source [7]
*seams*to be much more reliable, and goes through a quick meta analysis (with cited sources) to conclude that "*In other words, our*[American]*kids can not measurement in either*[imperial or metric]*system of measurement.*" - That being said, I believe this discussion should be more about the remove of source [8] that appears to me as unnecessary. Regards WinterNurgle (talk) 07:39, 17 July 2018 (UTC)

## A few considerations[edit]

I'd like to highlight the followings points:

- The title "Metric system" may be misleading as the article either deals with the US metrification, or is understood that way. The very first section "The SI" clarifies the point by stating that the metric system was
~~one amongst others~~the 'prototype' of the SI. After that, the*metric system*seams to switch to*the unamerican system of units used to simplify the unpatriotic engineers' jobs*which is -I believe- the point that the article is aiming to debunk. - The section "Awesome simplicity" is... say... obscure for non American readers as they will lack of the original reference, because... say... they aren't used to the imperial system. Maybe a simple table (imperial versus metric) would help foreign readers to grasp the fore mentioned awesome simplicity.
- The "Metric Time" section worth to be mentioned, maybe it would fit better as part of the 'history' part of the "The SI" section. It was -and is still- a good example of what happens when the laypeople acceptance limits is reached when working things are forcibly modified.
- The "The practical metric system is broken too" section contains -in my point of view- two major errors:

- the non decimal units system for time: the SI only mentions the second as a time unit and
*prescribes how to measure it*. Minute, hour, day, week (and all the family) are outside of the SI (just check to the several definitions of a day if you like headaches). In regards of the SI, one hour should be expressed as 3.6 kiloseconds (and yes, it's ugly). Also, date and time formats are defined by the ISO 8601. Therefore, blaming the usage of non decimal unit for time stamping in unfair for the poor SI :'( - the speed being written in km/h is not a proof of the SI failure, if it was the point. There is, at my current knowledge, no technical mean to actually measure a speed. It can be
**computed**as the difference of positions in space divided by a difference of times (both of them being**measured**independently), or by derivation of an acceleration (which can be**measured**too, but not in the scope of the SI). The SI itself is*merely*only about how to measure a unit of a dimension.

- the non decimal units system for time: the SI only mentions the second as a time unit and

Also, what about the misusage of the SI prefixes in computer science ? Regards --WinterNurgle (talk) 14:05, 17 July 2018 (UTC)

- @WinterNurgle Good points made. Frankly, I think this article is pretty weak in its current shape; it pales in comparison to what they have at Wikipedia, which is much more informative. You cannot debunk nonsense if your article lacks substance. Please feel free to edit this article and make it better. Nerd (talk) 14:10, 17 July 2018 (UTC)
- It's hard to avoid confusing the SI and the metric system. The article could mention how prior to the current SI, there was a whole different system of metric measurements, the Centimetre–gram–second system of units
^{}which was evidently even worse. - Measuring speeds in km/h is stupid because the SI units aren't considered useful by people using vehicles. If people don't use a unit, that's generally because it doesn't suit their purposes, which is the chief criticism of metric and SI units.
- It's also a failure of the SI measurement of time that it doesn't include common periods like the day and year, instead being based on the arbitrary second. You (the OP) admit the concept of an hour as 3.6 ks is ugly, but try to blame ISO?
- And you can't clearly distinguish "computing" something from "measuring it" - all measurement involves computation, e.g. measurement of mass is generally done by mesuring the weight and scaling by the acceleration due to gravity; measurement of distance is often done using light or radar range-finders, which again involve a computation, or by GPS... You could "measure" speed by measuring kinetic energy, or by measuring red shift (used for speed of astronomical objects), but again calculation is needed. --Gospatric (talk)
- @Gospatric, you made some good points too but I disagree with the difficulty to distinguish metric system from the SI. First the metric system was an ancestor of the SI (as reminded by the article), fine, let's consider it has changed. Now it's (according to WP, yes I am a lazy person) a subset of the SI. Ok, both are quite similar in the end but one contains the other. Needless to say that when using the 'modern' metric system, one use
*de facto*the SI. I think the confusion comes from a bad habit -no offense intended- in the usage of these words. And I would add the bad habit may comes from the very usage of the words 'metric system'. - I missed my point with the km/h issue, sorry. 'km/h' as a unit is as useful as 'mph' -for instance to guesstimate how long one has to drive to arrive at the
*rendez-vous*point- and both fit nicely the purpose of driving safely (just because local signs are in the same unit). My point was initially that km/h is not an SI unit strictly speaking. For this topic, the SI defines both the metre and the second as units, that's it. If the ISO 8601 wants to defines the hour as 1/24 of the regular day duration of a given year (I don't remember which one), that's ok in the end but the hour is therefore a derived unit of the second ('coz the 'regular day duration of a given year' is still to be measured to know how many seconds there are in an hour). Now let's go further and imagine that the ISO 8601 is revised, and the hour is redefined as the 1/24 of the stellar day duration of the 12/12/12 (huhu). The duration of the hour may change a little bit but not the one of the second, despite both of them being arbitrary chosen. In short, 'km/h' should not be considered as part of SI unless the hour is defined as a collection of seconds. Ok, I'm somehow trolling, as it is commonly accepted that one hour equals 3.6000 kiloseconds but ain't technically speaking true. - About my assessment that 3.6 ks is ugly were a simple statement I intended to be humoristic. There is no point to blame the ISO, unless an ISO is edited to standardize the ugliness. In addition, the lack of hour or day definition can't be considered as a failure of the SI, as already stated, day duration is defined by ISO not the SI. Why the frenchies did not bother define a day duration in their damn metric system soon to become the SI? Well, it was
~~thought about with the metric time idea~~not in the scope. This SI consists of a set of base units, prefixes and derived units. Thanks to ISOs, people from around the globe tend to agree upon how to use these units to facilitate communications and commercial exchanges, the determination of the day duration being an example. - You are very right with the measure/calculation point. Nowadays, the very vast majority of measurements implies calculation to at least render the measured value. Please have a look at the VIM and GUM. Calculations in the measurement process are part of the 'measuring system'. For instance, take a quartz watch -an instrument that measures time periods. Typically, the watch's second is defined by a group of oscillations of the resonating quartz. Hence, the watch only has to 'count' oscillation of the quartz to determine if a time period (let's say a second) has passed or not since the last detected second. This calculation (the oscillation counting) may be either done by mechanical or digital means, but remain in the 'measuring system' that provides a measurement of elapsed time periods. Now, what I called
*computation*was referring to calculations using as input the value of measurements (that may include calculations) to generate an output value. This last value has not been measured but calculated, that's the case of speed that cannot be measured directly but require the measurement of two values before a speed value can be process. I'll go further and respond to each of your examples:**measurement of mass is generally done by mesuring the weight and scaling by the acceleration due to gravity**: the weight is measured and the mass is computed as you stated and provided the acceleration due to gravity has been measured too (!).**measurement of distance is often done using light or radar range-finders**: good example as only the travel duration of light is measured, calculations being part of the measuring system (photometer + chronometer = distance, just think about it).**GPS**: Geolocalization is perform by trigonometry, only maths here.**kinetic energy**: kinetic energy can only be calculated as E=1/2mv^{2}provided one knows both the mass and the velocity.**measuring red shift (used for speed of astronomical objects)**: I'm not sure about how the red shift is determined but I'll guesstimate that it require a few photometers (at different wavelengths to spot the shift) and a chronometer (to quantify the shift). Implying computation for 'measuring' red shift.

- Guys, thanks you for reading as I tend to easily getting off the road --WinterNurgle (talk) 09:51, 18 July 2018 (UTC)

- @Gospatric, you made some good points too but I disagree with the difficulty to distinguish metric system from the SI. First the metric system was an ancestor of the SI (as reminded by the article), fine, let's consider it has changed. Now it's (according to WP, yes I am a lazy person) a subset of the SI. Ok, both are quite similar in the end but one contains the other. Needless to say that when using the 'modern' metric system, one use

- It's hard to avoid confusing the SI and the metric system. The article could mention how prior to the current SI, there was a whole different system of metric measurements, the Centimetre–gram–second system of units

Ok, so just to let you know, I allowed myself to perform some rework on the article. --WinterNurgle (talk) 11:54, 20 July 2018 (UTC)

- No kidding, Winter. What you've accomplished is a total re-write, and in a style that I personally find pedestrian. Your work is more than should be undertaken without consensus. Ithaca8 (talk) 14:15, 20 July 2018 (UTC)
- @Ithaca8 Do you feel I went too far with the modifications? Are there sections more impacted than other? Or is that you disagree on some parts I added? Anyway, sorry for my pedestrian writer's skill -I guess "pedestrian" isn't a compliment- English is not my mother tongue. But I assume the talk page is expected to be talking about the article to improve it. I would be more than pleased if you could provide a more detailed feedback. Thanks in advance. --WinterNurgle (talk) 06:10, 23 July 2018 (UTC)

I moved @WinterNurgle's changes to Draft:Metric system rewrite as they were severely lacking in proofreading. Feel free to fix it up there. I believe we should have two pages, this one which just explains the system and how it works (an "outline"-style page) and one covering its adoption (metrication). —Kazitor 09:06, 24 July 2018 (UTC)

## Roko's basilisk[edit]

Should 'non-decimal measurements' and the 12-counters be encouraged, because the conversion programs will impede the theoretical progress of the basilisk (eg Atnıñ könlek yulı and Troy/avoirdupois pounds and ounces.

At one point rubber bands were being sold as X inches long by Y millimetres wide. Anna Livia (talk) 15:47, 17 July 2018 (UTC)

## kitchen measurement errors[edit]

A metric cup in most countries is 250mL, not 0.2 litres. Not really important but while a metric tablespoon is typically 15mL, in Australia is is 20mL. 14.2.65.246 (talk) 06:55, 4 January 2019 (UTC)

- It's very mixed internationally between 200 and 250 ml (while other measures abound for the traditional, non-metric cups of different nations): Cup (unit)
^{}has a lot of details. 250ml is dominant in the English-speaking Commonwealth but not elsewhere. Feel free to edit to make it more international. --Annanoon (talk) 10:08, 4 January 2019 (UTC)

## Good Example[edit]

I don't suppose we could insert the fact that 1 milliliter of water weighs 1 gram, takes up 1 centimeter cubed and takes 1 calorie(the small calorie) to heat it by 1 degree Celsius. Féinléiriú (talk) 18:18, 4 March 2019 (UTC)

- I prefer things a bit larger. One liter (or cubic decimeter) of water has a mass of one kilogram and takes 4184 joules (or one kilocalorie of the proper kind, not the nutritionist's revision) to be heated up by one degree Celsius. Nerd (talk) 18:27, 4 March 2019 (UTC)
- Done. Zero
^{(talk - contributions)}19:15, 4 March 2019 (UTC)

- Done. Zero

## A historical viewpoint[edit]

A book from 1970 on Decimalisation I read recently said that switching to the metric system of units from the complex multiplicity of systems in the then current system would be kinder to children (they have just learnt base 10 and then have to learn a multiplicity of other number-bases (paraphrasing) and free up some teaching time. Anna Livia (talk) 10:31, 19 March 2019 (UTC)