Hacker News Reader

Comment by gumby | Hacker News Reader

> He claimed that the old, so-called “imperial” standard was not only “more perfect” than the alternative—a highly dubious claim at best...

What a slur. Division into twelfths (and sixtieths) was quite common in measurements and currencies around the world because of the convenient affordances of all the factors. Most also relied heavily on powers of two (most notably the US version of the "imperial" system) which are extremely convenient. The reliance on rational numbers makes computation in the head very easy.

And the units are more "humane" for customary activity (a stair riser is 2/3 of a foot; a cup is a common quantum for food consumption, a mile is roughly a thousand paces etc). A mm or cc is way too small and a meter is kind of gigantic (yards are less common than feet). A litre works fine though.

There's a lot to like about the si system, but division by ten was a disaster, and the lack of convenient units is a persistent bug.

View on HN

All in all I prefer the SI system, but the Imperial system has it's advantages. 5280 feet seems really arbitrary, but can halve it five times and still get an integer.

It also divides evenly by 3.

For comparison:

1/3 of a mile is 1760 feet. 1/2 of that is 880 feet 1/2 of that is 440 feet 1/2 of that is 220 feet 1/2 of that is 110 feet 1/2 of that is 55 feet.

1/3 of a km is 333.333333 meters 1/2 of that is 166.666667 meters 1/2 of that is 83.333333 meters 1/2 of that is 41.666667 meters 1/2 of that is 20.833333 meters 1/2 of that is 10.416667 meters

Damn it, the imperial guys must have really messed up their beautiful divisible system by using a thousandth of an inch in machining.

The only reason to believe that a "cup" is more convenient than a deciliter, or a "mile" is more convenient than a kilometer, is that you grew up with those units.

16 cups in a gallon, 12 inches in a feet, 1760 yards in a mile. It's not humane that children should memorize these completely arbitrary scales and weird names.

For lots of measures you're correct, but that's not really true for all cases. Even in highly-metric France they use but cuiellères a soupe and so forth in addition to mL, because it's a more convenient measure. An egg matches with about a cup of flour for a batter--eggs don't exist in fractional powers of ten.

I also think (again in common household uses like setting a thermostat or talking about the weather or a fever) a fractional degree celsius is false precision, since you can't feel it, and a whole degree celsius is too coarse, so something that ranges from 0-100 in the temperatures you're likely to encounter is better than a scale which ranges from 0-100 over (the equally arbitrary) liquid phase of water. Of course it's marginal, but it's not entirely true that (unlike the metric system) all these measures are totally arbitrary.

There are advantages and disadvantages to these systems. If you have to convert inches to miles a lot--yeah, the metric system performs much better for that. But conversions of scale or dimension--while extremely common in science and engineering--are not likely in common usage, while fractional division is much more common. It's likely that you don't recognize the advantages of an alternate system merely because you're unfamiliar with it.

> The only reason to believe that a "cup" is more convenient than a deciliter, or a "mile" is more convenient than a kilometer, is that you grew up with those units.

From this statement I doubt you know where I grew up.

I've made these arguments before. The lack of wide, common adoption of the metric system is a common plank in U.S.-bashing.

The metric system is convenient for calculations involving conversions of scale or dimension (e.g. "How long is my finger, in kilometers?" "What is the rough mass of a cubic meter of water?"). The standard units are more convenient for calculations involving division, as you point out.

These are convenient in different arenas and it doesn't surprise me that these different arenas use different systems. For science and engineering uses, the metric system is a lot better, and it's in wide use. For the common human-scale uses you point out, the standard units are more convenient.

People often pooh-pooh the matter of "convenient" units but the fact is that teaspoons and tablespoons are still used for cooking, even in France itself. And these aren't approximations but (as they are in the U.S.) strictly defined according to a standard.

The metric system makes a great standard, which is why the U.S. fully adopted it and all weights and measures are defined in terms of the metric system. The metric system is taught in schools. There's just not a compelling reason to, for common and mundane uses, to switch to it; and some disadvantages.

(I always wondered why decimeters weren't more popular with metric users, they seem convenient enough. But they do seem to get by fine with piles of centimeters.)

For common use the imperial system is the best, more human scale for all relevant measures.

For scientific use, nothing beats the metric system of course. Having to go imperial would probably significantly increase the amount of migraines scientists have on a daily basis.

Reply on news.ycombinator.com