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> I find the imperial system fits in better with that warmth of humanity

Right, so you enjoy warmth such as: 1 foot = 12 inches, 1 stone = 14 pounds, 1 pound = 16 ounces. Lots of useless names and numbers to memorize compared to kilo = 1000, milli = 0.001.

> in favor of cultural uniqueness and fun over conformity

You're writing in impeccable English. As we know, English is an international language and most definitely not the pinnacle of cultural uniqueness or non-conformity. Why not adopt a more esoteric and fun language for yourself such as, who knows, Esperanto, Lojban, Klingon, etc.?

> in contrast to [...] the cold calculation of the more “scientific” metric system

Decimals are optimized for cold calculation, yes. Would you like to use a monetary system based on pounds, shillings, and pence - like the UK and Australia right into the 20th century? Did you know that the New York Stock Exchange traded in increments of $1/8 and later $1/16, before fully decimalizing?



> Right, so you enjoy warmth such as: 1 foot = 12 inches, 1 stone = 14 pounds, 1 pound = 16 ounces. Lots of useless facts to memorize compared to kilo = 1000, milli = 0.001.

Most of life is just useless facts, I think it's fun and I enjoy it.

> You're writing in impeccable English. As we know, English is an international language and most definitely not the pinnacle of cultural uniqueness or non-conformity. Why not adopt a more esoteric and fun language for yourself such as, who knows, Esperanto, Lojban, Klingon, etc.?

I've been learning French actually and have really enjoyed it. When I was in France recently I was able to put some of those skills to the test and found it fun and interesting to see how both difficult, and in some other cases, incredibly easy to fit in even with knowing maybe a hundred or so words and basic grammar. I speak English since that was what I grew up with. English is actually pretty fun as a language too because of the chaos of the very language itself. Read vs read, &c.

But all cultures have some things that are unique and also not very unique about them. I'm not sure why we can't just have our measuring system like we do today and that's just one unique thing about the United States.

To turn this around the other way, maybe everyone should just eat at McDonalds and conform to what's most popular and efficient?

> Decimals are optimized for cold calculation, yes. Would you like to use a monetary system based on pounds, shillings, and pence - like the UK and Australia right into the 20th century? Did you know that the New York Stock Exchange traded in increments of $1/8 and later $1/16, before fully decimalizing?

Yea sure. How many basis points is $1/8?


Basis points are a ratio (1/100 of a percent), not an amount.


I enjoy the warmth of the distance light travels in a vacuum in 1/299,792,458 of a second, or as me and my friends call it: a Meter.


For those who don't know: The original definition of a metre is 1/40 000 000th of a full circle of longitude of Earth. That was considered not accurate enough, so it was redefined as the length of a certain metallic bar kept in Paris. Then it was defined in terms of wavelengths of krypton light. Finally, it was redefined in relation to the speed of light.

But each time the metre was redefined, the new definition was within the error bounds of the previous definition and the instruments that could be used within the previous definition - this ensured that backwards compatibility was retained. That's how we end up with these weird-looking numbers; it's not for fun and games.

Meanwhile, backwards compatibility was absolutely broken many times in traditional and imperial measurement systems. Heck, we have a break even in recent history: The survey foot has been discontinued in terms of the international foot, but they differ by 2 parts per million. That might not sound like much, but if you're measuring a whole continent, then being wrong by 2 ppm over 3000 km means having a discrepancy of 6 m, which is more than enough to fit an extra house in.


> For those who don't know: The original definition of a metre is 1/40 000 000th of a full circle of longitude of Earth.

That’s incorrect. It’s “one ten-millionth of the distance from the equator to the North Pole along a great circle through Paris” (https://en.wikipedia.org/wiki/Metre). Different fraction, and much better defined (different circles of longitude may have different lengths)

> That was considered not accurate enough, so it was redefined as the length of a certain metallic bar kept in Paris.

I can’t find a reference, but I think it at least partially was a matter of practicality, not of accuracy. It’s not simple to measure that 10,000 km distance (https://en.wikipedia.org/wiki/Arc_measurement_of_Delambre_an...: The arc measurement of Delambre and Méchain was a geodetic survey carried out by Jean-Baptiste Delambre and Pierre Méchain in 1792–1798 to measure an arc section of the Paris meridian between Dunkirk and Barcelona. This arc measurement served as the basis for the original definition of the metre.)


Thank you both for that info. I didn't know any of that (except for the metal bar in Paris).


More on the backward compatibility of the metre, this video released 7 hours ago explains it nicely: https://youtu.be/PWbfVcDcfFw?t=1039 Joseph Newton - "Cursed Units 3: The British Empire Strikes Back".

Other parts of the video highlight the insanity of inconsistent and shifting definitions of imperial units such as the mile, gallon, fluid ounce, pound-force/pound-mass, etc. It's one big damning essay against pre-metric units.


And then there are short vs. long tons (neither of which is a metric tonne)... nautical vs. statute miles... troy vs. regular vs. fluid ounces...


Handily enough the speed of light is about a foot per nanosecond, give or take. A nanosecond doesn't sound like much, unless you start to work out, for example, how many bits are inside your 40Gbps USB-C cable at the moment (they do travel at less than the speed of light).


Grace Hopper used to hand out pieces of wire to represent nanoseconds. She used pepper to represent picoseconds.


Here in Canada, my family ran a fishing camp with a lot of US customers. I was talking with one of them about metric vs. US units and to demonstrate I said how about this: How many gallons in a cubic mile? And he was able to work it out in his head, and pretty quickly too. Whoa. The point I was trying to make that is than in metric (say, liters per cubic kilometer) you just need to get the number of zeroes right, but you can't argue with results.


I was able to do something similar by using gross approximations and conversions to/from metric. My coworker had just bought a surplus stainless steel water tank for solar heating, and was wondering how much it would weigh when full. It was cylindrical, so I asked him for the diameter and the height. In my head I converted those measurements to inches, then to centimeters by multiplying by 2.5. I divided the diameter by 2, squared it, and multiplied by 3 (close enough to pi) to get the area. Then I converted the area and the height to their nearest power of 2 so I could take advantage of logarithms. Multiplying the area and height was as easy as adding the exponents, which gave me cubic centimeters. The weight of water is almost by definition 1 gram per 1 cc. Divide by 1000 to get kg by subtracting 10 from the exponent, then multiply by 2 to get approximate pounds by adding 1 to the exponent. By the time he was done telling me the dimensions, I had an answer for him. It definitely wasn't correct, but all he needed was a ballpark anyway.


> he was able to work it out in his head, and pretty quickly

That's a scary ability. I wonder if that guy is equally adept at converting acre-feet to gallons, or if he's a one-trick pony.

Here's what I know without looking anything up: 1 mile = 1760 yards, 1 yard = 3 feet, 1 foot = 12 inches; 1 US gallon = 231 cubic inches (exact conversion, and a weird number at that). So 1 cubic mile = (63360 inch)^3 = 7707820032000/7 gal ≈ 1.101 trillion US gallons.

Fun fact, combustion engine displacements used to be quoted in cubic inches. Note that 61 in^3 ≈ 1 litre.


It's not too difficult to know or calculate inches in a mile:

    12 * 3 * 1760 = 12 * 5280 = 63,360
A few Americans may know how many cubic inches in a US gallon:

    231 
But I don't believe anyone (apart from rainman/prodigy circus performers) can do this in their head:

    63360^3 / 231 = 1,101,117,147,428.571
Estimate yes; calculate no.


That's probably what it was, an engineering estimate with a couple of significant digits. It's been years.


The pre decimal systems were built with lots of prime factors. The divisions were less obvious but arguably more convenient (it's often simpler to separate something into 8ths than 10ths, and so on).


I love the way 360 (degrees) divides evenly by so many small integers: 2, 3, 4, 5, 6, 8, 9, 10, 12, 15.


I created 360 shares in a small business I set up many years ago incase we ever needed to a few more share holders


> 1 foot = ...

hold on: a horizontal foot, or a vertical foot ? 0.30480061m versus 0.3048m


> Right, so you enjoy warmth such as

... Yes, I think that was unironically exactly the point.

> You're writing in impeccable English.

Which is a ornery bastard of a language with more exceptions than rules. It's about aesthetic, not popularity.

> Would you like to use a monetary system based on pounds, shillings, and pence

I wouldn't be surprised.

Your entire comment comes across like you think you're exposing contradictions that really just aren't contradictions at all.


>Lots of useless names and numbers to memorize

Do you have problems with time too? I mean, 1 minute = 60 seconds, 1 hour = 60 minutes, but one day = 24 hours? Wtf??! And one week = 7 days! And one month is 30 unless you mean an actual month which is anywhere from 28 to 31. And the year is 365 days, unless it's a leap year with 366. How do you cope with that?


Back in the 1970's I tried to come up with a metric time system by breaking a day into powers of 10. A centiDay was 14.4 minutes.

I realized it would never catch on, because a 30 minute TV show would have to fit into 28.8 minutes, and the only way to do that was to lose a couple of commercials. Never gonna happen.


Back in the 1790s some Frenchmen did the similar thing but, despite not having TV and commercials it still did not catch up even in France.


> Do you have problems with time too? How do you cope with that?

I have memorized how time and dates work, but I do not enjoy the system.

Time is my biggest sore point. For starters, doing any kind of arithmetic is an exercise in pain. For example when I rent a shared bike, the system tells me the start and end time to the second - for example, from 13:26:08 to 15:54:39. To calculate the duration, I have to combine the HMS into linear seconds, subtract the two linear timestamps, and then reformat it into HMS notation. Similarly, if I have to calculate ratios, percentages, histograms, etc., then HMS notation just gets in the way.

Have you ever tried writing logic to deal with HMS before? Here's an exercise for you (which I completed this month): Given a non-negative integer number of seconds, write out the number as a string formatted in DHMS format such that the leftmost unit cannot have leading zeros (so no 0m23s, no 09s) except for the special case of 0s, the string must be fully reduced (e.g. 83s -> 1m23s), and any non-leftmost unit must have full leading zeros (e.g. 1h2m3s -> 1h02m03s). The logic is pretty horrendous. The alternative, if everything was expressed in linear seconds, is completely trivial.

The second sore point about time notation is that although sub-second units (ms, μs, ns, etc.) are fine and dandy, any SI super-second unit (kilosecond, megasecond, etc.) is never used in practice and also has no alignment with days and years. This isn't merely a theoretical concern because that's how we get non-SI units like km/h, kW⋅h, and light-year. If ks was useful and popular, then km/ks just simplifies to m/s, whereas km/h = 3.6 m/s and kW⋅h = 3.6 MJ. Personally, I would've preferred the day to be subdivided into either a thousand or a million ticks, especially because I strongly prefer power-of-1000 prefixes (so milli- is good, centi- is bad).

As for dates, we can't get around the fact that there are roughly 365.25 days per tropical year. The Gregorian calendar is hacky because February is shorter than other months, a leap day is put at the end of February instead of the end of December, and the naming is shifted so that Sep (number 7) = 9th month, Oct (number 8) = 10th month, Nov (number 9) = 11th month, Dec (number 10) = 12th month. I think the least bad solution is the https://en.wikipedia.org/wiki/International_Fixed_Calendar .

>> Lots of useless names and numbers to memorize

You are correct to point out that time units have many weird names and conversion factors. Now on top of that, try learning all these names and conversion factors:

• Length: 1 mile = 1760 yards (let's skip furlongs and chains even though they are part of the derivation of the mile), 1 yard = 3 feet, 1 foot = 12 inches. Then there are industry-specific measures like mils in machining, points in typesetting, nautical miles.

• Volume: 1 US gallon = 4 quarts, 1 quart = 2 pints, 1 pint = 2 cups, 1 cup = 8 fluid ounces, 1 fluid ounce = 2 tablespoons, 1 tablespoon = 3 teaspoons. Also, 1 US gallon = 231 cubic inches exact, surprisingly. Throw in some more industry-specific units like cubic feet of water, cubic inches of engine displacement, acre-feet of rain, cubic miles of dirt mined, barrels of oil...

• Mass: 1 short ton = 20 hundredweights, 1 hundredweight = 100 pounds, 1 pound = 16 ounces, 1 ounce = 480 grains; also, 1 stone = 14 pounds (pervasive in UK but nonexistent in US).

• Power: horsepower, BTU/h, ton of cooling, possibly foot-pound-per-second.

The point is, all of the above names and numbers are completely arbitrary and you have to learn them all from scratch. If you aced the test on units of length, that has told you exactly nothing about the units of mass.

It should go without saying in the metric system, the following series mean exactly what you think they mean:

• Length: ... nanometre, micrometre, millimetre, metre, kilometre, megametre, gigametre, ... .

• Volume: ... nanolitre, microlitre, millilitre, litre, kilolitre, megalitre, gigalitre, ... .

• Mass: ... nanogram, microgram, milligram, gram, kilogram, megagram (metric ton / tonne), gigagram, ... .

• Power: ... nanowatt, microwatt, milliwatt, watt, kilowatt, megawatt, gigawatt, ... .

• Frequency: ... nanohertz, microhertz, millhertz, hertz, kilohertz, megahertz, gigahertz, ... .

If you know how many metres are in a kilometre, you know how many hertz are in a kilohertz - you didn't need to learn anything new. You just needed to think for two seconds upon the first time you heard that prefixed unit.

An LED bulb advertised as 2000 lumens (lm) can be easily rewritten as 2 kilolumens (klm) if you wanted to. A power bank marketed as 20000 mA⋅h can at least be simplified to 20 A⋅h (and 72 kilocoulombs if you get rid of the hour).


I don't know what do you do, but most people need to know how many yards (or inches, or feet, or chains, or whatever) in a mile as often as they need to know how many seconds, minutes, or hours in a quarter i.e. never. Yet it's the strongest point proponents of the metric system have, so makes me wonder why are they so agitated?

For the record, I am from a metric country and immigrated to the US as an adult. I still find American system to be more adjusted to human needs. E.g. temperature in F does not need decimals unlike temperature in C, tool sizing in inches is simpler (look at the sets of drill bits in different systems for example), tire pressure in psi (e.g. one of my bikes is 53 psi rear and 51 front, or 3.65 and 3.51 bars, you could say I could remember just the decimals, but another bike is 33 and 31, or 2.27 and 2.13 so no, it's 3 digits with bars vs 2 in psi), house dimensions are in even number of feet so much easier to find furniture, which is designed with this in mind, obviously. Miles are great to estimate time of travel by car, take 1 minute per mile of distance on a highway and 2 minutes in the city and you will be pretty close.

But, of course, the reason the American system is never going away is because it would be insanely expensive: you either will have to rewrite all building codes/standars/recipes with stupid conversions e.g 50.8x101.6 instead of 2x4 even though the lumber dimensions are not really 2 and 4 inches or scrape them and write the new ones using the more sensible metric dimensions but then you will need to scrape all the tooling you had and buy new, metric tools. All so you could say how many micrometers in a kilometer and feel smart?


> Miles are great to estimate time of travel by car, take 1 minute per mile of distance on a highway and 2 minutes in the city and you will be pretty close.

That might be true where you live, but it's hardly a universal constant. 1 minute per mile might be sort-of-universal for long distance Interstate driving, but then again, you can just as easily phrase that as ~1 hour per 100 km in metric.

I'm rather doubtful about your 2 minutes per mile (= 30 mph average speed) figure for "city" driving, though – how's that even possible when urban maximum speeds are usually in the 25 – 40 mph range, and that's not counting time lost for traffic lights and other intersections, general congestion and parking?

Checking a few destinations around where I live in Germany, non-Autobahn cross-country driving is closer to 2 minutes per mile rather than 1 minute per mile (and highly variable depending on your exact destination, so no point trying to estimate driving times to the nearest minute, anyway), and never mind actual urban driving.


>That might be true where you live, but it's hardly a universal constant.

I have not said it's a universal constant, it's true in the US, where we use miles. ~1 hour per 100km is not as easy.

I cannot say I care much if you are doubtful, especially if you live in Germany and not in the US, I doubt many people in the US will care about your doubts too.


Even in the US I'm doubtful about 2 minutes per mile being true for actual "city" driving if you live in a bigger conurbation.




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