7 ms·

You are definitely (and thankfully) not the norm. Imperial units are awful. They're more ... human, maybe, in that a foot is about one human foot long, and t

You are definitely (and thankfully) not the norm. Imperial units are awful. They're more ... human, maybe, in that a foot is about one human foot long, and that an inch is about one human thumb width, and how 0F feels "pretty cold" and 100F feels "pretty hot", and to me the charm of imperial units begins and ends right there. Those are literally the only redeemable qualities about imperial units, and they have nothing at all to do with their utility as a tool for measurement. I am glad that you like them. Use them all you like. I won't.

stass 8y ago
What are the redeamable qualities of metric units?
- saagarjha 8y ago
  It’s based on the decimal system, which we happen to use in our primary numerical system as well?
  - blhack 8y ago
    We use the decimal system for imperial units too. Thousands of an inch, millionths of an inch, etc.
    - csihar 8y ago
      In most practical applications that I've seen fractions of imperial measurements used, it tends to be in powers of 2, i.e., 3/16 inch, 1/4 mile, etc. Decimals can certainly be used, but for most applications where you'd use something like a "millionth of an inch," it's vastly more common to use metric.
      - blhack 8y ago
        What applications are you talking about? Just for a general example of the sort of thing I'm talking about: https://youtu.be/EWqThb9Z1jk?t=137 https://youtu.be/EWqThb9Z1jk?t=137 They're resurfacing a surface plate, which has to be very flat. If you listen to the exchanges between them, everything is being done in millionths of an inch.
      - jpindar 8y ago
        In my experience (electronics manufacturing), both PCBs and machined parts are usually in mils or decimal inches, although millimeters are becoming more common and many drawings show both systems.
        pcnix 8y ago
        This might be specific to where you live though, in my experience in the electronics industry, I've pretty much only seen millimeters.
    - guelo 8y ago
      Or nothing is stopping you from using things like 1.3 inches, 2.7 miles, .6 gallons. I tend to use the fractions when doing measurements in my head. But if things get too complicated and I have a calculator I switch to decimal.
- kderbyma 8y ago
  Frankly, while mathematically speaking 12 is a great base, people don't think in twelves - you can quickly perform arithmetic and our entire education system of math relies on base 10. Kind of hard to suddenly add two fingers to everyone. Additionally, base 12, would not act like 12 does in base 10, thus if base 12 is your key point of reference, a foot should be 10 in base 12 for inches.....
  - Just_Smith 8y ago
    People don't really think in terms of 10s either - that's just societal conditioning based on the usage of fingers to count. If you can accurately picture 1/3 of set, but your number system cannot, it's not really that accommodating of a system. By the way, you can count base12 on your hands using the digits of your fingers. We just teach kids to use fingers because it's the norm.
    - jodrellblank 8y ago
      Why are you so obsessed with thirds? If you care about short, clean fractions on a human scale, base 6 is overall better, see this table: https://youtu.be/qID2B4MK7Y0?t=992 https://youtu.be/qID2B4MK7Y0?t=992 Plus you get all the convenience of having five digits on a hand and 5 as the highest counting digit, so you can count to 55 on two hands, and all the rest of the benefits in that (totally serious) video.
    - DareRight 8y ago
      A numbering system based on human fingers would be base6.
      - umanwizard 8y ago
        You've got it backwards. Counting to ten on your fingers predates the concept of our modern positional number system by hundreds of thousands of years. That's why base 10 was already the well-established natural choice when that system was invented. Thinking that you could represent the quantity IIIIIIIIIIIIIIIIIIIII by the string "21" because it's 2 * 10 + 1, or similarly as "three fingers on left hand, three fingers on right hand" seems obvious to us now, but is actually pretty recent technology relative to the whole timescale of human development
- bdamm 8y ago
  They're globally standard, decimal, and internally consistent. One never needs to wonder how many meters in a kilometer or how many grams in a kilogram. They have some human usable qualities as well; it's convenient that water freezes at 0°C and that a kilogram of water is also a liter.
  - ubernostrum 8y ago
    a kilogram of water is also a liter I have never, in around four decades of living, had an actual need to determine the mass of a given volume of water, or the volume of a given mass of water. When cooking, I routinely need to split some quantity of an ingredient into thirds or quarters. Yet I am also constantly told that I'm ignorant and backwards and irrational for preferring a system that optimizes for the latter, rather than for the former. Base 12 is genuinely better for many real-world applications than base 10, those applications are more common in the lives of non-scientists than the applications metric is optimized for, and I doubt you're going to be able to produce a rational argument otherwise.
    - atoav 8y ago
      So you never went hiking for a longer period of time or did anything that actually involves carrying water. I remember when some guys thought about building a pool on the balcony, calculating how much water weighs is admitably not ver often used, but when it is the consistency of the metric system is nice. I work with wood in mm for years and never had any problem with the metric system. Finding the third, fifth or sixth or whatnot is not hard if you are used to it at all. Converting from mm to meters isn’t hard, etc. Having a number like 666.66 mm probably sounds scary to measure (beyond the religious connotations), but in fact it is a point on a line that is easy enough to find.
    - xanipher 8y ago
      But that's because your recipes are built on the easy divisibility, no? If your recipes are built on weight measurements, suddenly "easy divisibility" brings nothing to the table. If you cook with a kitchen scale, "one ml of water is one gram" is used all the time.
- atoav 8y ago
  The metric prefixes we know and love are a huge plus. If you convert from Volt to kV or to mV, you just need to move your comma. Ah see what I did there? I uses a metric prefix on a unit that is also used in the US. The thing is 1V is also 1Nm or 1J or 1Ws. So suddenly we have the meter there right besides the Newton. In fact if you look beyond "I build my own shed in the US"-scenarios, you will find the meter everywhere intertwined in the definition of other units. In fact the definition of imperial length units is based on the metric definition of the length light travels through vacuum in 1/299792458s. So the foundation of the meter is light speed, which helps with all kind of practical issues in physics. The metric system has maximum compatibility to all these unit systems (except the °C which is a more-practical-for-every-day-use offset version of Kelvin). Unit systems are always something you grow up with and are therefore an emotional topic. People will take fractions of inches as an example of how metric fractions fail to deliver, when in fact no european woodworker has even remotly a problem with doing their thing in mm. In front of me lies a ruler with a 0.1mm scale and a caliper with 0.01mm or 1/128In accuracyIf I really wanna be ±0.01mm accurate on a cut of 1/3m or 333.33mm getting that accuracy would not be easier in inches. My saw blade is precisely 2mm wide anyways..
  - cies 8y ago
    V=J/C V*C = J = Nm = Ws
blhack 8y ago
>They're more ... human, maybe, in that a foot is about one human foot long, and that an inch is about one human thumb width, and how 0F feels "pretty cold" and 100F feels "pretty hot", and to me the charm of imperial units begins and ends right there. As far as we know, humans are the only thing in the universe that care about any of this stuff. A computer couldn't care less if you are using 1 foot or 0.3048 meters. Why not optimize for humans, the things actually using these things? Optimizing for the computer just seems...silly. It seems like something somebody from the 1970s would have thought was a futuristic idea.
- Just_Smith 8y ago
  Also, the statement that metric is more useful for measurement largely ignores the fact that Imperial has stuck around so long because of its usefulness in trade work. It's definitely ONLY because of base12, but being base12 - imo - positions it far beyond metric for daily use. There's a reason why food items so commonly come by the dozen. Why would anyone prefer to build a house using a system that can't even accurately measure 1/3?
  - naikrovek 8y ago
    1/3 can easily be measured in metric... it's just not a whole number. Far out I can invent a system that is unique to everything, and I can create my own abominable conversion ratios all I like. It doesn't make the system superior, it makes my system necessarily inferior. My TV is now 12 Settos in size. My surround system consumes 12 audots of power. My fridge holds 12 cubic fudo of room. There. Now everything is easily divisible by 12ths. I won't even go into conversion factors on this insanity. Metric is objectively the better system to anyone that doesn't have a decades-long familiarity with the stupidity that is the imperial system. That's coming from an american without a college education, by the way. I am the target demographic for the pro-imperial people. I wasn't abducted into any metric-only education system and forced to convert or fail and disappoint my family. I was a disappointment by my own hand, thank you very much.
    - fingerlocks 8y ago
akira2501 8y ago
> They're more ... human, maybe I think both systems of units typical cases are dominated by human factors. Anecdotally, humans tend to use one of three scales for their preferred choice of measurement and they tend to be smaller-than-human, human, larger-than-human. For example, the km. I see mm, m and km used quite often.. but the other bases are almost never used. A prime case for this is "what is the distance to the sun?" If you're going to round your answer then the most concise form is 150 Gm, yet most people will still say something like "150 million km" which is unnecessarily long and non-canonical, but is much more familiar to the human mind and makes comparisons to everyday experiences much simpler. You can see this factor occur with just about every other metric base unit, even though the conveniently prefixed part of the system would be "better" for all technical definitions. Just as easily you could use imperial units and just overlay the metric prefix and scaling rules on top of them and it would be no more or less accurate or better than the metric system of units. > Use them all you like. I won't. I use whatever is convenient or common for the application.. if it gets complicated or I need a conversion, I use a unit-system aware language or environment to do my calculations. It really obviates the importance of the choice of unit and allows you to think about the fundamental problem more clearly along with many other benefits including conversion of units at any stage of calculation.
- comex 8y ago
  Nitpick: centimeters are also used often.
- cgriswald 8y ago
  > A prime case for this is "what is the distance to the sun?" I was attending a kids planetarium show as a volunteer and the professor asked this question and a kid proudly shouted “1 AU!”
- madstap 8y ago
  In Norway hectograms are frequently used. We use them for things like potato salad at the deli counter, pick'n mix candy, berries and small-time-dealer quantities of hash.
sonnyblarney 8y ago
Imperial units are good for describing small items in 'feets' length, and for cooking measures. I don't think miles have an advantage over kilometers. In Canada, people have trouble understanding the various measures if '10ml' of this, or '10mg' of that. They do understand 'a teaspoon' or a 'large spoon'. I think we need some kind of colloquial measure for food.
- kiriakasis 8y ago
  Recipes in cups are one thing I cannot understand, I do have a scale, I can measure everything with that
  - sonnyblarney 8y ago
    "Recipes in cups are one thing I cannot understand" ?? You drink out of cups every day; this is what humans, even you understand. 'A scale' is inapplicable while you're buying food or reading labels. Why use a scale when everyone knows what a cup and teaspoon are? They are human measurements. But it doesn't matter what you use, what matters is what people understand, and they don't understand grams and millilitres. It's been identified as a health problem: people don't have an intuition for the units on labels - there should be imperial units to help them understand. As for litre/gallon or pound/kg I don't think it matters ... but consider for a moment that everyone in Canada that I know still uses pounds. And feet/inches for height. I don't know a single person that can tell you their weight in Kg, maybe heir height in meters but they'd have to think about it.
    - ygra 8y ago
      My cupboard has cups in all kinds of sizes. Which one is the right one to use as a measurement? And for baking there's quite a big difference if my cups are 150 ml or 350 ml, especially when paired with counted ingredients like eggs. That's the problem with cups.
      - sonnyblarney 8y ago
        All of your regular coffee cups are exactly 250ml. Regular people use them for basic baking all the time, like making pancakes. 'Cups' are still better measures than ml because even you, in your self-acclaimed ignorance have a sense of how much a cup is whereas people do not have any idea how much '300ml' is. Canadians have no clue what 10ml of anything is. Canadians will continue to use feet and pounds for personal measure, despite being surrounded by total metric system - that should tell you something. Do you order beer in ml? Or pints? Seriously, do you know anyone that orders a 473ml of beer? So why pints? And not ml? Because it makes sense. Everything should be in metric, but many things should also be Imperial because metric is not useful for many common measurements. The entire construction industry in Canada still uses Imperial, and it also weirdly makes sense. Inches and feet are slightly more approachable at smaller scale.
tzs 8y ago
For mass, distance, area, and volume metric has an obvious advantage because for all of those we regularly deal with such a range of values that we want subunits, and basing those subunits on powers of 10 fits in much better with our number system and makes computation and conversion easier. This lets one make a pretty good argument that metric has advantages sufficient to justify having to buy new rulers and scales. For temperature, what is the justification for switching from F to C? We don't usually subdivide temperature units, so really all C does different from F is change the size of the degree and what physical process the scale is calibrated to. One can argue that the physical processes chosen for C calibration are more convenient than those for F. C was 0 == water freezing, 100 == water boiling. F was 0 == temperature of a mixture of water, ice, and ammonium chloride, 100 == body temperature of a healthy man. But that could have been fixed without changing the scale at all. Just redefine F so that 32 == freezing of water, 212 == boiling of water. That would fix the one problem F had without requiring anyone to get a new thermometer.
- floatboth 8y ago
  > what is the justification for switching from F to C? The rest of the world already using ℃. Imagine no more dual scale thermometers, no more switches in weather apps, etc :D
  - tzs 8y ago
    Sorry, I guess I was not clear. I didn't mean what would be the justification for switching from F to C now in the US. I meant what was the justification for adopting C initially for the metric system instead of using F? For other metric units, there were serious problems with the pre-metric units. For example, Wikipedia says that by the time of the French Revolution, the existing system had become impractical for trade. It doesn't say why it had become impractical, but my guess would be it had a lot to do with no good standard values for the units. If the units are not well defined in a way that gives the same values everywhere, it makes long distance trade harder. I base this guess on doing some research once to figure out why they did not defined the meter to make conversion to Imperial easier. Since they were free to define the meter any way they wanted, they could have made 1 meter == 1 yard, which would have made conversions of long distances easier. Or they could have defined the millimeter as 1/25th of an inch, which would have made conversions of short distances easier than the 1/25.4th of an inch that we ended up with. As far as I was able to determine, this was never an option because, as far as I could find, there was no widespread agreed definition of inches, feet, yards, etc. All that was standard was the relationships among them (1 foot == 12 inches, 3 feet == 1 yard, and so on). There probably was no way to fix that without adopting a completely new unit, because if they tried to just make a new standard for, say, the yard I'm sure it would have gotten bogged down in arguing over whose yard to base it on. The French would think everyone should adopt their yard, the English would think everyone should adopt theirs, and so on. So, a new unit, based on something not tied to any one region or nation, makes sense. Temperature did not suffer from this, or did not suffer from it in a way that was not easily fixable. F was based on a reproducible physical 0 point based on the temperature of a brine with a self-stabilizing temperature. The only problem F had was that there had been some waffling over the other calibration point, which had been fixed well before the first attempts at a metric system. So...why did they pick C?
AngryData 8y ago
Fractional units are extremely useful in construction and machining. Now you could use fractions with meters, but nobody does, and im not sure why other than 10 is a shitty starting point for fractions and you end up with crazy fucked denominators.
- atoav 8y ago
  The typical woodworker knows by hard all “crazy fucked” denominators like 333.333 mm for a third, 200 mm for a fifth etc. The idea that not having straight fractional values somehow makes it harder is just plainly false. When you tell anybody to cut a third of a meter they will just happily cut 333.33 mm down to their usual tolerance

stass 8y ago

What are the redeamable qualities of metric units?

saagarjha 8y ago
It’s based on the decimal system, which we happen to use in our primary numerical system as well?
- blhack 8y ago
  We use the decimal system for imperial units too. Thousands of an inch, millionths of an inch, etc.
  - csihar 8y ago
    In most practical applications that I've seen fractions of imperial measurements used, it tends to be in powers of 2, i.e., 3/16 inch, 1/4 mile, etc. Decimals can certainly be used, but for most applications where you'd use something like a "millionth of an inch," it's vastly more common to use metric.
    - blhack 8y ago
      What applications are you talking about? Just for a general example of the sort of thing I'm talking about: https://youtu.be/EWqThb9Z1jk?t=137 https://youtu.be/EWqThb9Z1jk?t=137 They're resurfacing a surface plate, which has to be very flat. If you listen to the exchanges between them, everything is being done in millionths of an inch.
    - jpindar 8y ago
      In my experience (electronics manufacturing), both PCBs and machined parts are usually in mils or decimal inches, although millimeters are becoming more common and many drawings show both systems.
      - pcnix 8y ago
        This might be specific to where you live though, in my experience in the electronics industry, I've pretty much only seen millimeters.
  - guelo 8y ago
    Or nothing is stopping you from using things like 1.3 inches, 2.7 miles, .6 gallons. I tend to use the fractions when doing measurements in my head. But if things get too complicated and I have a calculator I switch to decimal.
kderbyma 8y ago
Frankly, while mathematically speaking 12 is a great base, people don't think in twelves - you can quickly perform arithmetic and our entire education system of math relies on base 10. Kind of hard to suddenly add two fingers to everyone. Additionally, base 12, would not act like 12 does in base 10, thus if base 12 is your key point of reference, a foot should be 10 in base 12 for inches.....
- Just_Smith 8y ago
  People don't really think in terms of 10s either - that's just societal conditioning based on the usage of fingers to count. If you can accurately picture 1/3 of set, but your number system cannot, it's not really that accommodating of a system. By the way, you can count base12 on your hands using the digits of your fingers. We just teach kids to use fingers because it's the norm.
  - jodrellblank 8y ago
    Why are you so obsessed with thirds? If you care about short, clean fractions on a human scale, base 6 is overall better, see this table: https://youtu.be/qID2B4MK7Y0?t=992 https://youtu.be/qID2B4MK7Y0?t=992 Plus you get all the convenience of having five digits on a hand and 5 as the highest counting digit, so you can count to 55 on two hands, and all the rest of the benefits in that (totally serious) video.
  - DareRight 8y ago
    A numbering system based on human fingers would be base6.
    - umanwizard 8y ago
      You've got it backwards. Counting to ten on your fingers predates the concept of our modern positional number system by hundreds of thousands of years. That's why base 10 was already the well-established natural choice when that system was invented. Thinking that you could represent the quantity IIIIIIIIIIIIIIIIIIIII by the string "21" because it's 2 * 10 + 1, or similarly as "three fingers on left hand, three fingers on right hand" seems obvious to us now, but is actually pretty recent technology relative to the whole timescale of human development
bdamm 8y ago
They're globally standard, decimal, and internally consistent. One never needs to wonder how many meters in a kilometer or how many grams in a kilogram. They have some human usable qualities as well; it's convenient that water freezes at 0°C and that a kilogram of water is also a liter.
- ubernostrum 8y ago
  a kilogram of water is also a liter I have never, in around four decades of living, had an actual need to determine the mass of a given volume of water, or the volume of a given mass of water. When cooking, I routinely need to split some quantity of an ingredient into thirds or quarters. Yet I am also constantly told that I'm ignorant and backwards and irrational for preferring a system that optimizes for the latter, rather than for the former. Base 12 is genuinely better for many real-world applications than base 10, those applications are more common in the lives of non-scientists than the applications metric is optimized for, and I doubt you're going to be able to produce a rational argument otherwise.
  - atoav 8y ago
    So you never went hiking for a longer period of time or did anything that actually involves carrying water. I remember when some guys thought about building a pool on the balcony, calculating how much water weighs is admitably not ver often used, but when it is the consistency of the metric system is nice. I work with wood in mm for years and never had any problem with the metric system. Finding the third, fifth or sixth or whatnot is not hard if you are used to it at all. Converting from mm to meters isn’t hard, etc. Having a number like 666.66 mm probably sounds scary to measure (beyond the religious connotations), but in fact it is a point on a line that is easy enough to find.
  - xanipher 8y ago
    But that's because your recipes are built on the easy divisibility, no? If your recipes are built on weight measurements, suddenly "easy divisibility" brings nothing to the table. If you cook with a kitchen scale, "one ml of water is one gram" is used all the time.
atoav 8y ago
The metric prefixes we know and love are a huge plus. If you convert from Volt to kV or to mV, you just need to move your comma. Ah see what I did there? I uses a metric prefix on a unit that is also used in the US. The thing is 1V is also 1Nm or 1J or 1Ws. So suddenly we have the meter there right besides the Newton. In fact if you look beyond "I build my own shed in the US"-scenarios, you will find the meter everywhere intertwined in the definition of other units. In fact the definition of imperial length units is based on the metric definition of the length light travels through vacuum in 1/299792458s. So the foundation of the meter is light speed, which helps with all kind of practical issues in physics. The metric system has maximum compatibility to all these unit systems (except the °C which is a more-practical-for-every-day-use offset version of Kelvin). Unit systems are always something you grow up with and are therefore an emotional topic. People will take fractions of inches as an example of how metric fractions fail to deliver, when in fact no european woodworker has even remotly a problem with doing their thing in mm. In front of me lies a ruler with a 0.1mm scale and a caliper with 0.01mm or 1/128In accuracyIf I really wanna be ±0.01mm accurate on a cut of 1/3m or 333.33mm getting that accuracy would not be easier in inches. My saw blade is precisely 2mm wide anyways..
- cies 8y ago
  V=J/C V*C = J = Nm = Ws

blhack 8y ago

>They're more ... human, maybe, in that a foot is about one human foot long, and that an inch is about one human thumb width, and how 0F feels "pretty cold" and 100F feels "pretty hot", and to me the charm of imperial units begins and ends right there. As far as we know, humans are the only thing in the universe that care about any of this stuff. A computer couldn't care less if you are using 1 foot or 0.3048 meters. Why not optimize for humans, the things actually using these things? Optimizing for the computer just seems...silly. It seems like something somebody from the 1970s would have thought was a futuristic idea.

Just_Smith 8y ago
Also, the statement that metric is more useful for measurement largely ignores the fact that Imperial has stuck around so long because of its usefulness in trade work. It's definitely ONLY because of base12, but being base12 - imo - positions it far beyond metric for daily use. There's a reason why food items so commonly come by the dozen. Why would anyone prefer to build a house using a system that can't even accurately measure 1/3?
- naikrovek 8y ago
  1/3 can easily be measured in metric... it's just not a whole number. Far out I can invent a system that is unique to everything, and I can create my own abominable conversion ratios all I like. It doesn't make the system superior, it makes my system necessarily inferior. My TV is now 12 Settos in size. My surround system consumes 12 audots of power. My fridge holds 12 cubic fudo of room. There. Now everything is easily divisible by 12ths. I won't even go into conversion factors on this insanity. Metric is objectively the better system to anyone that doesn't have a decades-long familiarity with the stupidity that is the imperial system. That's coming from an american without a college education, by the way. I am the target demographic for the pro-imperial people. I wasn't abducted into any metric-only education system and forced to convert or fail and disappoint my family. I was a disappointment by my own hand, thank you very much.
  - fingerlocks 8y ago

akira2501 8y ago

> They're more ... human, maybe I think both systems of units typical cases are dominated by human factors. Anecdotally, humans tend to use one of three scales for their preferred choice of measurement and they tend to be smaller-than-human, human, larger-than-human. For example, the km. I see mm, m and km used quite often.. but the other bases are almost never used. A prime case for this is "what is the distance to the sun?" If you're going to round your answer then the most concise form is 150 Gm, yet most people will still say something like "150 million km" which is unnecessarily long and non-canonical, but is much more familiar to the human mind and makes comparisons to everyday experiences much simpler. You can see this factor occur with just about every other metric base unit, even though the conveniently prefixed part of the system would be "better" for all technical definitions. Just as easily you could use imperial units and just overlay the metric prefix and scaling rules on top of them and it would be no more or less accurate or better than the metric system of units. > Use them all you like. I won't. I use whatever is convenient or common for the application.. if it gets complicated or I need a conversion, I use a unit-system aware language or environment to do my calculations. It really obviates the importance of the choice of unit and allows you to think about the fundamental problem more clearly along with many other benefits including conversion of units at any stage of calculation.

comex 8y ago
Nitpick: centimeters are also used often.
cgriswald 8y ago
> A prime case for this is "what is the distance to the sun?" I was attending a kids planetarium show as a volunteer and the professor asked this question and a kid proudly shouted “1 AU!”
madstap 8y ago
In Norway hectograms are frequently used. We use them for things like potato salad at the deli counter, pick'n mix candy, berries and small-time-dealer quantities of hash.

sonnyblarney 8y ago

Imperial units are good for describing small items in 'feets' length, and for cooking measures. I don't think miles have an advantage over kilometers. In Canada, people have trouble understanding the various measures if '10ml' of this, or '10mg' of that. They do understand 'a teaspoon' or a 'large spoon'. I think we need some kind of colloquial measure for food.

kiriakasis 8y ago
Recipes in cups are one thing I cannot understand, I do have a scale, I can measure everything with that
- sonnyblarney 8y ago
  "Recipes in cups are one thing I cannot understand" ?? You drink out of cups every day; this is what humans, even you understand. 'A scale' is inapplicable while you're buying food or reading labels. Why use a scale when everyone knows what a cup and teaspoon are? They are human measurements. But it doesn't matter what you use, what matters is what people understand, and they don't understand grams and millilitres. It's been identified as a health problem: people don't have an intuition for the units on labels - there should be imperial units to help them understand. As for litre/gallon or pound/kg I don't think it matters ... but consider for a moment that everyone in Canada that I know still uses pounds. And feet/inches for height. I don't know a single person that can tell you their weight in Kg, maybe heir height in meters but they'd have to think about it.
  - ygra 8y ago
    My cupboard has cups in all kinds of sizes. Which one is the right one to use as a measurement? And for baking there's quite a big difference if my cups are 150 ml or 350 ml, especially when paired with counted ingredients like eggs. That's the problem with cups.
    - sonnyblarney 8y ago
      All of your regular coffee cups are exactly 250ml. Regular people use them for basic baking all the time, like making pancakes. 'Cups' are still better measures than ml because even you, in your self-acclaimed ignorance have a sense of how much a cup is whereas people do not have any idea how much '300ml' is. Canadians have no clue what 10ml of anything is. Canadians will continue to use feet and pounds for personal measure, despite being surrounded by total metric system - that should tell you something. Do you order beer in ml? Or pints? Seriously, do you know anyone that orders a 473ml of beer? So why pints? And not ml? Because it makes sense. Everything should be in metric, but many things should also be Imperial because metric is not useful for many common measurements. The entire construction industry in Canada still uses Imperial, and it also weirdly makes sense. Inches and feet are slightly more approachable at smaller scale.

tzs 8y ago

For mass, distance, area, and volume metric has an obvious advantage because for all of those we regularly deal with such a range of values that we want subunits, and basing those subunits on powers of 10 fits in much better with our number system and makes computation and conversion easier. This lets one make a pretty good argument that metric has advantages sufficient to justify having to buy new rulers and scales. For temperature, what is the justification for switching from F to C? We don't usually subdivide temperature units, so really all C does different from F is change the size of the degree and what physical process the scale is calibrated to. One can argue that the physical processes chosen for C calibration are more convenient than those for F. C was 0 == water freezing, 100 == water boiling. F was 0 == temperature of a mixture of water, ice, and ammonium chloride, 100 == body temperature of a healthy man. But that could have been fixed without changing the scale at all. Just redefine F so that 32 == freezing of water, 212 == boiling of water. That would fix the one problem F had without requiring anyone to get a new thermometer.

floatboth 8y ago
> what is the justification for switching from F to C? The rest of the world already using ℃. Imagine no more dual scale thermometers, no more switches in weather apps, etc :D
- tzs 8y ago
  Sorry, I guess I was not clear. I didn't mean what would be the justification for switching from F to C now in the US. I meant what was the justification for adopting C initially for the metric system instead of using F? For other metric units, there were serious problems with the pre-metric units. For example, Wikipedia says that by the time of the French Revolution, the existing system had become impractical for trade. It doesn't say why it had become impractical, but my guess would be it had a lot to do with no good standard values for the units. If the units are not well defined in a way that gives the same values everywhere, it makes long distance trade harder. I base this guess on doing some research once to figure out why they did not defined the meter to make conversion to Imperial easier. Since they were free to define the meter any way they wanted, they could have made 1 meter == 1 yard, which would have made conversions of long distances easier. Or they could have defined the millimeter as 1/25th of an inch, which would have made conversions of short distances easier than the 1/25.4th of an inch that we ended up with. As far as I was able to determine, this was never an option because, as far as I could find, there was no widespread agreed definition of inches, feet, yards, etc. All that was standard was the relationships among them (1 foot == 12 inches, 3 feet == 1 yard, and so on). There probably was no way to fix that without adopting a completely new unit, because if they tried to just make a new standard for, say, the yard I'm sure it would have gotten bogged down in arguing over whose yard to base it on. The French would think everyone should adopt their yard, the English would think everyone should adopt theirs, and so on. So, a new unit, based on something not tied to any one region or nation, makes sense. Temperature did not suffer from this, or did not suffer from it in a way that was not easily fixable. F was based on a reproducible physical 0 point based on the temperature of a brine with a self-stabilizing temperature. The only problem F had was that there had been some waffling over the other calibration point, which had been fixed well before the first attempts at a metric system. So...why did they pick C?

AngryData 8y ago

Fractional units are extremely useful in construction and machining. Now you could use fractions with meters, but nobody does, and im not sure why other than 10 is a shitty starting point for fractions and you end up with crazy fucked denominators.

atoav 8y ago
The typical woodworker knows by hard all “crazy fucked” denominators like 333.333 mm for a third, 200 mm for a fifth etc. The idea that not having straight fractional values somehow makes it harder is just plainly false. When you tell anybody to cut a third of a meter they will just happily cut 333.33 mm down to their usual tolerance