The super-slow conversion of the U.S. to metric (2025) • Hacker News Board

Re: The super-slow conversion of the U.S. to metric (2025)

#281

Post by evil-olive » Wed, Jan 21, 2026, 6:17 PM UTC

threemux wrote: post #62

I'd part with cups and teaspoons/tablespoons and the like, but you'll pry inches/feet/yards and fahrenheit from my cold, dead hands. They're both more convenient for daily use. I think I'd prefer to keep miles as well but I don't have a good reason for that one. Fahrenheit has more precision without using decimals for the thing 99% of people are using temperature measurements for: air temp. Where I live, we generally…

> Inches/feet being base 12 divides better into thirds and fourths, which is very useful in construction.

all of the math normal people use in everyday life happens in base 10.

"it's easy because it's base 12" is an absolutely ludicrous idea.

what's 7'5" divided by 3? divided by 4?

what happens if you need to divide by 5?

and sure, there are various mental math tricks you can learn to make this easier...or you could just use the metric system.

7'5" is 226cm. that's a normal, boring, everyday, base 10 integer.

you don't need to learn a special set of "mental math for base 12" tricks. instead you can re-use the same mental math tricks you use for every other base 10 number.

Re: The super-slow conversion of the U.S. to metric (2025)

#282

Post by relaxing » Wed, Jan 21, 2026, 6:17 PM UTC

ericmay wrote: post #125

relaxing wrote: post #122

Earlier quoted context omitted.

You think Frank Lloyd Wright designed big picture windows and open floor plans because he was afraid of humanity? He was afraid so he tried to induce fear? Through asymmetry? What then of William Blake’s “fearful symmetry”? Amazing that FLW is still traumatizing conservatives 100 years later. Ayn Rand was a fan, didn’t you know? Picasso was trying to convey the feeling of being bombed from the sky in a civil war, so…

> You think Frank Lloyd Wright designed big picture windows and open floor plans because he was afraid of humanity? He was afraid so he tried to induce fear? No, I was speaking about the exterior. The blending in of the surroundings, and hiding of things like the entrance are the hallmark of post-war architectural trends. Not that I'm claiming Lloyd suffered from the same PTSD that returning American veterans did, bu…

> No, I was speaking about the exterior.

But windows are exterior? The idea that massing of interior influences the form of the exterior is part of Wright's philosophy. I don't believe you know what you speak of.

> The blending in of the surroundings, and hiding of things like the entrance are the hallmark of post-war architectural trends. Not that I'm claiming Lloyd suffered from the same PTSD that returning American veterans did, but his building follows some of the same patterns.

First I've heard the sensitivity to natural surroundings was because of war. Wright lived through the Spanish-American war and the Great War, but completed Fallingwater before WW2 (which is what we generally mean by "postwar.")

> For example, here: where's the door? http://www.wright-house.com/frank-lloyd-wright/fallingwater-...

You can look up plans online if you're really curious, but since you asked it's right there, in the shadow. Maybe stop basing architectural opinions on underexposed photos. Or is it because you want a grand entrance that announces the owner's ostentatiousness?

> I don't understand this comment. Why would I care what Ayn Rand thinks or thought?

You're espousing some conservative viewpoints, so I figured you'd be interested in others.

> Western artists have forgotten what art is and what the purpose of it is

Bizarre opinion. Artists philosophizing on the definition of art and its purpose is the defining feature of modern art. You're just mad they concluded it extends beyond Renoir's florid, gauzy depictions of girls.

Re: The super-slow conversion of the U.S. to metric (2025)

#283

Post by nine_k » Wed, Jan 21, 2026, 6:18 PM UTC

wffurr wrote: post #196

JKCalhoun wrote: post #77

"Back when I was a Catholic-school kid in northern Wisconsin, my school lessons briefly focused on the metric system. This was in the late 1970s." Man, the progressive school (Comanche Elementary in Overland Park, Kansas!) must have had a huge impact on my life. In addition to open classrooms (I was in Unit 5, not 4th Grade), team teaching, a focus on experimental science, a circular layout to the school with a sunke…

>> But then [post-1970s] some kind of shit seemingly started to poison the country. https://wtfhappenedin1971.com/ - the oil ran out and the post-war boom ended.

You mean, cheap oil ran out. Also, the last remaining sort-of-gold-standard was abolished, so the money printer could go brrr without much restrain, as needed.

Re: The super-slow conversion of the U.S. to metric (2025)

#284

Post by nine_k » Wed, Jan 21, 2026, 6:22 PM UTC

rconti wrote: post #268

beloch wrote: post #242

To those who cling to customary units because... 1. "They're more intuitive". They're not. You're just familiar with what 70 F feels like. If you're used to metric, 70 F is meaningless, but you intuitively know what 20 C feels like. 2. "Metric leads to lots of awkward numbers." All systems will fortuitously have round numbers in some contexts and awkward numbers in others. Customary units are different in that there…

Counterpoint to #1, celsius increments are too large. I laugh every time I see a thermostat in a car or home that needs to have steps like 20, 20.5, 21, 21.5.. :)

Do you honestly notice the difference in comfort between 20°C and 20.5°C? I suspect even the heating element is not that precise, let alone the actual room temperature.

They only case in daily practice where 1°C is too large is the difference between normal body temperature (36.5°C) and mild fever (37.0°C), but thermometers have to be graduated in much smaller subdivisions anyway.

Re: The super-slow conversion of the U.S. to metric (2025)

#285

Post by ddellacosta » Wed, Jan 21, 2026, 6:22 PM UTC

bigstrat2003 wrote: post #267

ddellacosta wrote: post #203

Earlier quoted context omitted.

As a pretty experienced American home baker I don't understand how you can assert that it's faster to measure volume with cups or etc. than to put a bowl on a scale and simply pour stuff in, measuring everything in grams. It's not even close in terms of speed, convenience, _and_ accuracy.

It is indeed not even close, but not in the way you are asserting. It takes a second to dip a measuring cup into the flour and level it off. So if I need 4c of flour, it takes me about 4 seconds. Meanwhile, to measure with a scale I have to slowly, carefully pour into the bowl so that I don't overshoot the amount I'm going for (and then then sometimes I overshoot and have to try to scoop the ingredient out a bit). Vo…

Welp not much I can say to that or to RandallBrown's response, seems obvious our experience and way of thinking is pretty different on this matter.

(EDIT: Also fwiw I often use a spoon or whatever to scoop things into the bowl, vs. pouring, which means I have more control but can still offload the measuring part to the scale...)

Whatever gets the delicious baked goods in your mouth I guess

Re: The super-slow conversion of the U.S. to metric (2025)

#286

Post by frankus » Wed, Jan 21, 2026, 6:23 PM UTC

buildsjets wrote: post #237

If you specify all your bolt heads as 19mm and 13mm, then a 3/4" wrench or a 1/2" wrench is usually good enough to get the job done. Similarly, a 1/4-20 bolt will fit in a M6 tapped hole if you use a large enough hammer. A hazardous aspect of US threadforms is that #10-32 machine screws and #8-32 machine screws have the same pitch. So you can fit #8 bolts in a #10 hole and sometimes, they FEEL like they made good tor…

The diabolical case is M5 versus 10-32. About a 4% difference in diameter and about 0.8% difference in thread pitch. Basically indistinguishable with the naked eye and even the "nest the threads in each other" check doesn't help without a pretty long length of threads.

Re: The super-slow conversion of the U.S. to metric (2025)

#287

Post by amanaplanacanal » Wed, Jan 21, 2026, 6:23 PM UTC

ericmay wrote: post #143

amanaplanacanal wrote: post #137

Earlier quoted context omitted.

Yes please, for the sources on assymetrical architecture and stress. That's totally new to me, and I'd love to read about it.

Cognitive Architecture by Ann Sussman is probably the best single book about this topic that I've found. https://annsussman.com You may find this lecture of interest. I'm sorry I don't have anything shorter to read offhand. https://www.youtube.com/watch?v=LPjezxPl3FA -edit- This might get you closer though to the general theory: https://asla-ncc.org/the-built-environment-impacts-our-healt...

Thank you! I read the article in your edit, and the point about symmetry seems unrelated to the rest of the article, and doesn't mention any science. I'll have to research further.

Intuitively it doesn't resonate with me. The environment humans evolved in (the natural world) doesn't have much of anything symmetrical, unless it was built by humans.

Re: The super-slow conversion of the U.S. to metric (2025)

#288

Post by samus » Wed, Jan 21, 2026, 6:26 PM UTC

vondur wrote: post #152

It’s a bit odd in the U.S. because we use a mix of units, largely due to industries that combine metric and imperial systems. Most people are familiar with metric volume since so many drinks are sold in 1 and 2 liter bottles, and medications are typically measured in milligrams. Lengths and weights are more of a mixed bag. Many track and field events use metric units now, though longer distances are still measured in…

The smaller increments of Fahrenheit don't matter outside of a chemistry lab.

Re: The super-slow conversion of the U.S. to metric (2025)

#289

Post by scoofy » Wed, Jan 21, 2026, 6:27 PM UTC

rconti wrote: post #268

beloch wrote: post #242

To those who cling to customary units because... 1. "They're more intuitive". They're not. You're just familiar with what 70 F feels like. If you're used to metric, 70 F is meaningless, but you intuitively know what 20 C feels like. 2. "Metric leads to lots of awkward numbers." All systems will fortuitously have round numbers in some contexts and awkward numbers in others. Customary units are different in that there…

Counterpoint to #1, celsius increments are too large. I laugh every time I see a thermostat in a car or home that needs to have steps like 20, 20.5, 21, 21.5.. :)

I mean, it's arbitrary. I've lived in a Fahrenheit country and a Celsius country and both systems work fine. Resolution issues exist for both systems (you can still benefit from decimals in Fahrenheit for coffee and tea brewing)

I prefer Fahrenheit because it's based around the human, but it really doesn't matter, and it's probably better long term to have measurements that are not based around the human condition, but we're talking about benefits to society tens of thousands of years from now, rather than today.

Re: The super-slow conversion of the U.S. to metric (2025)

#290

Post by tzs » Wed, Jan 21, 2026, 6:27 PM UTC

SECProto wrote: post #259

candiddevmike wrote: post #132

Earlier quoted context omitted.

(F - 30) / 2 = ~C C * 2 + 30 = ~F

No need to simplify this. (F - 32) / 1.8 = C C * 1.8 + 32 = F I personally find the math just as easy to do accurately. For example, 87F -32/1.8 = 55/1.8 =~30.5C. Compare that to your approximate method, which would give 28.5C, which is just wrong (Maybe I just got really good at this when working a public facing job with a lot of American tourists - they would ask what our celsius temperatures were "in real units",…

For C to F you can often simplify the mental math by doing the multiply by doubling then taking off 10%.

E.g., to convert 31℃ to ℉: 31 x 2 = 62. Subtract 6.2 = 55.8. Add 32 = 87.8℉.

If you want to round the result to the nearest integer the subtract 10% step is a convenient place: 31 x 2 = 62. Subtract 6 (rounded 6.2) = 56. Add 32 = 88℉.