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The Father of Modern Metal

https://nautil.us/the-father-of-modern-metal-235939/
2•bookofjoe•1m ago•0 comments

How React server components work: an in-depth guide

https://www.plasmic.app/blog/how-react-server-components-work
1•azhenley•2m ago•0 comments

Waymo's Austin Geofence

https://twitter.com/WholeMarsBlog/status/1925990174678196684
1•lopkeny12ko•2m ago•0 comments

The GCC compiler back end can now bootstrap the Rust compiler

https://old.reddit.com/r/rust/comments/1ktph3c/media_the_gcc_compiler_backend_can_now_fully
1•todsacerdoti•2m ago•0 comments

Visual Studio Code for the Web

https://code.visualstudio.com/docs/setup/vscode-web
1•tosh•6m ago•0 comments

Bring Your Own System Prompt

https://www.jaces.com/insights/system-prompt
2•ajaces•6m ago•1 comments

CDC can no longer help prevent lead poisoning in children, state officials say

https://arstechnica.com/health/2025/05/cdc-can-no-longer-help-prevent-lead-poisoning-in-children-state-officials-say/
4•tzs•7m ago•0 comments

Val Town for Glitch Users

https://blog.val.town/glitch
1•stevekrouse•10m ago•0 comments

Heafodtramet

https://ang.wikipedia.org/wiki/Heafodtramet
1•mudkipdev•12m ago•0 comments

Writing with Emacs: Tips, Examples, and Resources for Writing with Emacs

https://github.com/thinkhuman/writingwithemacs
2•jamesgill•19m ago•0 comments

Flix: an effect-oriented, functional, imperative, and logic programming language

https://flix.dev/
3•thunderbong•20m ago•0 comments

Best Practice

https://blog.alexewerlof.com/p/best-practice
2•aeinbu•27m ago•0 comments

JPL to Transition to Onsite Work

https://www.jpl.nasa.gov/news/jpl-to-transition-to-fully-onsite-work/
4•cptroot•29m ago•0 comments

Relativistic quantum chemistry

https://en.wikipedia.org/wiki/Relativistic_quantum_chemistry
2•maj0rhn•29m ago•1 comments

The Source of "Water"

https://jamesgill.net/waterword/
2•stakkur•30m ago•0 comments

Local Business American Science and Surplus Launches GoFundMe

https://uwmpost.com/news/local-business-american-science-and-surplus-launches-gofundme
5•gabrielgironda•30m ago•0 comments

On "Vibe Coding"

https://tante.cc/2025/05/23/on-vibe-coding/
2•cratermoon•32m ago•1 comments

Purdue ECE students shatter World Record for fastest Rubik's cube-solving robot

https://engineering.purdue.edu/ECE/News/2025/purdue-ece-students-shatter-guinness-world-record-for-fastest-puzzle-cube-solving-robot
1•iamben•35m ago•0 comments

Just a QR Code

https://justaqrcode.com
2•vmbrasseur•36m ago•0 comments

Researchers cause Gitlab AI developer assistant to turn safe code malicious

https://arstechnica.com/security/2025/05/researchers-cause-gitlab-ai-developer-assistant-to-turn-safe-code-malicious/
1•cmsefton•37m ago•0 comments

Nuclear Engineer Reaction "The Highest Radiation Dose in Any Human Who Survived" [video]

https://www.youtube.com/watch?v=QCiILrMhw1M
1•firebaze•38m ago•1 comments

Google handed out decommissioned TPUs at I/O

https://twitter.com/marilynika/status/1925278423817363525
2•lanewinfield•39m ago•1 comments

Multiplayer AI chat and conversational turn-taking: sharing what we learnt

https://interconnected.org/home/2025/05/23/turntaking
2•bobbiechen•40m ago•0 comments

Decades On, SSRIs Remain Mired in Mystery and Debate

https://undark.org/2025/05/22/antidepressants-debate-maha/
2•EA-3167•41m ago•0 comments

Elon Musk's Fake Retreat from Doge

https://prospect.org/power/2025-05-23-elon-musks-fake-retreat-from-doge/
7•doener•41m ago•0 comments

The End of Glitch (Even Though They Say It Isn't)

https://keith.is/blog/the-end-of-glitch-even-though-they-say-it-isnt/
1•stevekrouse•42m ago•0 comments

Albert Stevens

https://en.wikipedia.org/wiki/Albert_Stevens
2•firebaze•44m ago•0 comments

The Case of the 'Lost' FOIA Requests

https://www.bloomberg.com/news/newsletters/2025-05-21/how-2-hackers-erased-hundreds-of-foia-requests
1•consumer451•45m ago•0 comments

Repo rule-files standards for AI Agents: chaos or convergence?

https://aiagentsexplained.substack.com/p/agent-rule-files-yet-another-tower
1•plataproxima•45m ago•1 comments

Use VS Code to build AI apps and agents [video]

https://www.youtube.com/watch?v=g0uOOGRYHT4
1•azhenley•45m ago•0 comments
Open in hackernews

The metre originated in the French Revolution

https://www.abc.net.au/news/science/2025-05-20/metre-treaty-anniversary-metric-system-measurement-metrology/105302024
59•Tomte•6h ago

Comments

skrebbel•5h ago
> (It was later found the astronomers were a bit off in their calculations, and the metre as we know it is 0.2 millimetres shorter than it should've been.)

That's actually impressively good accuracy for the time! Hats off to the astronomers.

hilbert42•4h ago
I was just about to post same quote but you beat me to it.

I'd go further, I think their work was a remarkable feat for the late 1790s. That they achieved that accuracy given the primitive equipment of the day says much for their abilities and understanding.

Also at the time France was in turmoil, numbers of its scientists were victims of the French Revolution—Antoine Lavoisier, probably the greatest chemist of his time—was beheaded by guillotine in 1794, so the political environment was anything but stable.

Look back 225+ years ago: there was no electricity, no material science to speak of to make precision instrumentation—journal bearings on lathes, etc. couldn't be made with the accuracy of today, backlash would have been a constant worry. All instrumentation would have been crafted by hand.

And the old French pre-metric system of units was an imperial system similar to the British (France even had an inch that was similar in length to British Imperial unit). All instrumentation up to that point would have relied on the less precise standards of that old system.

Traveling was by horse and sailing ship, and so on. Surveying would have been difficult. There wasn't even the electric telegraph, only the crude optical Chappe telegraph, and even then it was only invented in the 1790s and wasn't fully implemented during the survey.

They did a truly excellent job without any of today's high tech infrastructure but they made up for all these limitations by being brilliant.

In today's modern world we often underestimate how inventive our forefathers were.

selkin•3h ago
The pre-metric measurements in France weren’t imperial, but local: units had the same name, but different cities defined them differently. A livre[0] in one village was almost, but not quite, the livre used by the one only a couple toise[1] away.

[0] about a modern pound, depending where you were. Toulouse’s livre was almost 1.3 modern pounds, for example.

[1] about 13853/27000 meter.

hilbert42•38m ago
You're right, I should have put 'imperial' in quotes as it's not the same as the British Imperial measurement. You'll note however I did distinguish the French system from the British one by referring to it in lowercase, that was intentional.

The issue came up in a round about way on HN several weeks ago and I should have been more careful here because I wasn't precise enough in my comment then. As I inferred in that post 'imperial' nomenclature is used rather loosely to refer to measurement and coinage/currency as they're often closely linked (in the sense that the 'Crown' once regulated both).

Pre-revolution French coinage used the same 1/12/20 number divisions as did the old English LSD and currencies in other parts of Europe, and that system is often referred to as 'imperial' coinage which likely goes back to Roman Imperial Coinage — but to confuse matters it was decimal.

One can't cover the long historical lineage here except to mention the sign for the Roman [decimal] denarius is 'd' which is also used for the LSD penny, 12 of which make the shilling (£=240d).

So for various reasons both 'old' physical measurement and 'old' coinage are often referred to as (I)imperial. To add to the confusion, modern currencies when converting from LSD/1/12/20 to metric and '1/12… measurement' are often done around the same time. Nomenclature overlaps.

For example, I'm in Australia and the 1966 conversion from LSD to metrified coinage occurred shortly before the metrication of measurement. It was all lumped together as Imperial (note u/c) to Metric (that's how the public perceived it). The Government staged both changeovers close enough so that the reeducation of the citizenry wasn't forgotten by the time the measurement program started.

For the record here's part of length in the old French measurement system:

"Pied du Roi (foot) ≈ 32.48 cm (Slightly longer than an English foot, which is about 30.48 cm.)

Pouce (inch) = 1/12 of a pied ≈ 2.707 cm

Ligne = 1/12 of a pouce ≈ 2.256 mm

Toise ≈ 1.949 metres (A toise is 6 pieds.) <...>"

The other units can be found on the same site: https://interessia.com/medieval-french-measurements/

ahazred8ta•2h ago
There was a 12:1 ratio between the foot ' inch '' line ''' and point '''' in pre-decimal engineering. Yes, they used triple prime marks. The typographic point was originally 1/144th of an inch. Watches are typically measued in french pointes.
throwanem•5h ago
Yeah, I know. That's why I make fun of it some times. Not because it is French; though an American I hope I am not a damned ungracious American, and though I believe we may fairly call the original debt squared after Normandy, I recognize and respect the generous Gallic heart from which it sprang.

But "the" metric system, so called, functions entirely on the happy coincidence of macroscopic distance being divisible at human discretion, while the similar and simultaneous effort at decimalizing time foundered on the rocks of how long it actually takes Earth to revolve upon its axis and to circle the sun. Both efforts originate in the same silly hamartiac human desire to prescribe a shape to which reality must conform, and thus may come in for about equal gentle contumely on that score. Especially since, in another example of its designers' foolishly misplaced priorities, metric offers no units at the human scale. They may have prefigured the brutalists in this way.

Zanfa•5h ago
You mean like my feet aren’t a foot long, my thumb isn’t an inch? Ironically, my pinky is a centimeter thick and a meter is when I take a long step.
Joker_vD•5h ago
The width of my palm (with my thumb, tightly pressed to it) at its widest is 10 centimeters, which is quite handy.

Oh, and my "inch" is almost exactly 3 centimeters.

capitainenemo•5h ago
There's a couple of convenience approximations I use to work with US Imperial..

30cm is a "metric foot" (it's actually even closer to 1 light nanosecond which is kinda cool for thinking about distances at computer speeds)

250ml is a "metric cup"

throwanem•4h ago
And now the famous triviality of order-of-magnitude and unit conversion goes entirely out the window...
lostlogin•4h ago
Speaking of feet - I got irritated when buying shoes and trying to convert shoes sizes.

It turns out that UK/US sizes are based on the length of a barley corn.

Quite why it isn’t just in centimetres is baffling. https://en.wikipedia.org/wiki/Shoe_size

throwanem•4h ago
I'll give you this one, but only with the qualification that inches would be fine too. There's no benefit to the manufacturers in more rational standardization, though. As with women's clothing sizes, why would Levi's (for example) make it easier for me to find something that matches my style and budget, from anyone other than them? Hell, even men's sizes which nominally are in inches do this! I have to go a size up in Levi's vs Wranglers because Levi's size small, the bastards, while Lee mostly run true to size but none of their cuts is really worth wearing. And don't even talk to me about boot sizes!

Inches vs. centimeters? Baby stuff. Get on my level. :D

steamrolled•5h ago
The point of the SI system is not that one meter is "better" than one foot. It's that we picked one subjective point of reference and then made almost all the other units related to that in a straightforward way and scaled with a common set of prefixes.

In everyday life, the metric system offers no big benefit, except for consistency for international standards and trade. But if you're doing anything engineering-related, your life is simpler if you don't need conversion factors to move between liters, meters, joules, watts, amperes, volts, ohms, and so on.

And FWIW, even to the extent that US engineers sometimes use inches and Fahrenheit, almost everything else they do is anchored to SI.

kergonath•5h ago
> And FWIW, even to the extent that US engineers sometimes use inches and Fahrenheit, almost everything else they do is anchored to SI.

Inches are defined relative to the SI as well.

IAmBroom•3h ago
As are Fahrenheit degrees.
throwanem•3h ago
I don't know why people seem to think this is an "own."
throwanem•5h ago
Even when we use inches, they're frequently themselves metricated via division by 1,000 to produce the "thou." This is an extremely strong convention; I have one (inexpensive) digital caliper that can read in fractional inches, but every such tool I own reads in both millimeters and thou.

I do think it's funny all these folks insisting metric is so humanist seem never to have noticed which of their finger joints is an inch long. For me that's the second of the little finger, but I have large squarish peasant hands. As for the rest, treating a centimeter as 10/25 of an inch and vice versa seems to work well enough for measurements not requiring particular precision, or in other words anything I'd be comfortable doing without a caliper. Where's the trouble, really?

lostlogin•4h ago
Where does the ‘humanist’ bit end?

Should we go back to fathoms, furlongs, chains, drams and bushels?

This was settled a long time ago for the vast majority of the word.

throwanem•4h ago
If we should find they serve us better, why not?
nancyminusone•1h ago
>bushels

Someone hasn't been to an apple orchard recently.

bregma•1h ago
It's far more impressive to express gravity in units of stone furlong per fortnight squared. It's 7.14 x 10^10. Makes gravity on Jupiter look puny.
throwanem•36m ago
It's that plus or minus about three orders, sure.
fuzztester•18m ago
Just for fun, check the yojana and related Indian measures:

https://en.m.wikipedia.org/wiki/Yojana

https://en.m.wikipedia.org/wiki/History_of_measurement_syste...

alnwlsn•2h ago
Ah the joys of units! If you work cross-discipline, 1/1000th of an inch is called a 'thou' in machining. For PCBs (not unheard of to attach the two together), the same unit is called a 'mil'. Not to be confused with millimeter, even though it often is confused.
bregma•2h ago
> In everyday life, the metric system offers no big benefit

That's not entirely true. An American driving across the Canadian border on an interstate can automatically go from 55 to 100. That's almost twice as much.

throwanem•20m ago
No it isn't. Our speedos are denominated both ways, it's cheaper, and I drive a Nissan with a V6 and paddle shifters. Not that that's much in any real sense! But neither is a Piper Archer, and those also have enough power to make 100kph feel extremely tame. It's not a high bar, is what I'm saying.
kergonath•5h ago
> But "the" metric system, so called, functions entirely on the happy coincidence of macroscopic distance being divisible at human discretion

What do you mean exactly? Any distance is divisible arbitrarily, it’s a continuous scale regardless of the unit system. We could define the metre as a foot (or rather, as the distance of some physical phenomenon close enough to a foot) and build a decimal system out of it, and it would have the same advantages as the metric system.

> while the similar and simultaneous effort at decimalizing time foundered on the rocks of how long it actually takes Earth to revolve upon its axis and to circle the sun

The fact that there are 60 seconds in an hour and 24 hours per day has absolutely nothing to do with how quickly the earth revolves. Your argument works (kinda) for the number of days in a year, that’s all.

> Both efforts originate in the same silly hamartiac human desire to prescribe a shape to which reality must conform

No, this is completely backwards. This effort originates from the idea that we should observe and understand nature, and build a rational society based on this understanding. The original metre was a fraction of the length of a meridian for a reason. They did not change the size of the Earth to conform to an arbitrary unit. Instead they came up with a unit that made sense to them, for both philosophical and practical reasons. They did the opposite of what you say.

> Especially since, in another example of its designers' foolishly misplaced priorities, metric offers no units at the human scale

The metre is about 2 thirds of an average human height (give or take, the average also changed with time). How is that not a human scale? If you want to go lower, to the scale of something you can hold, you have centimetres. If you want to go larger, to the scale of a distance you can walk, you have kilometres. And all conversions and comparisons spanning the 5 orders of magnitude relevant to our daily lives are seamless and make sense. What is your problem with this system?

> They may have prefigured the brutalists in this way

That is actually hilarious. The enlightenment philosophers and humanists who came up with the metric system are polar opposites of the brutalists. They rationalised our understanding of the world around us. They did not rebuild it square.

throwanem•5h ago
> They rationalised our understanding of the world around us. They did not rebuild it square.

This is a distinction without a difference. Read James C. Scott, for pity's sake.

kergonath•2h ago
Well, no. I am not going to go through a collection of books by a random guy because someone said so on the Internet. If you can articulate the point you want to make, maybe. If the point cannot be made, I am not sure why I should be interested.
throwanem•2h ago
The short version is that you have this entirely backward and the "rationalizing" you describe not only remakes the world but does so by means of gruesome violence, and it is no accident the twitchy, haunted neurotics who attached their numericalizing madness to the Red Terror, had to go to such hideous lengths to get themselves taken at all seriously. We are not required to do the same two hundred years on, simply because they happen to have been on the side that wrote the history.

The long version is Seeing Like a State.

olau•1h ago
Seeing like a state does not argue against the meter system.

It just explains that many of these things got traction despite the resistance against them only because the state needed them.

In the case of measurement units, one was that the natural units varied in size and could be gamed, which is a big problem for fair tax collection.

throwanem•12m ago
I don't suppose I expected to need to clarify the difference between citing a work whose thesis informs my own, and quoting from a work where my thesis is actually stated. But it now being evident I was optimistic: This is the first one.
lostlogin•4h ago
> metric offers no units at the human scale.

How do you apply this to the imperial system?

I’ve heard this criticism before, but limited to temperature, with people saying they want more increments. I’m not sure why half a degree centigrade is so hateful.

throwanem•4h ago
Fahrenheit has finer divisions at the human scale, yes. A scale calibrated to the boiling point of water, at the top end, can tell me nothing useful about my environment beyond the manner in which it has probably killed me.
henrikschroder•1h ago
If Fahrenheit is better than Celsius because the units are smaller, doesn't that mean that the kilometre is better than the mile because it has smaller units?

It is all subjective. You like what you grew up with because it is familiar, not because it is better. You know by rote memorisation how much 100 feet is and what 75F feels like, the same way I know by rote memorisation how much 50 meters is and what 25C feels like.

throwanem•33m ago
Show me where I have at any time argued one system is better than the other, as opposed to precisely that no system is strictly preferable, and I'll answer this point. Until then I can't and thus also won't.

In the meantime your grasp of nuance or lack thereof is no pressing concern of mine. And my entire thesis has been flagrantly subjective throughout, save where the minor matter of relevant history is involved. To attempt to answer this with the charge of subjectivity, as though this accomplished other than to recapitulate what has been obvious all day, seems not only pointless but risible.

Mikhail_Edoshin•1h ago
A page of 8.5 x 11 units is more convenient to divide into parts than that of 210 x 297 units.
throwanem•28m ago
Yes, working to US letter size in my book blocks makes for fewer headaches over the guillotine cutter, whose scale is only graduated in 1/16 inches (0.0625", ~1.5mm) and whole millimeters. Oh, the wasted 20 thou would get cleaned up in the face finishing cut, but all the same, half an inch is a much more convenient quantum here than half a millimeter.
az09mugen•5h ago
Another fun fact dating from French revolution is the 10 hour-day, each hour had 100 minutes and each minutes 100 seconds : https://historyfacts.com/world-history/fact/france-had-a-cal...
paulorlando•5h ago
Fun fact... or not so fun?

For 12 years of the revolutionary era, France did use decimal time. And the calendar and clocks were organized around a 10 day week and a 10 hour day. But those changes, coupled with the loss of Sunday worship, had other effects on the population.

Here’s an assessment of what was really meant and then lost by the elimination of Sunday:

“‘The elderly ladies took advantage of the long journey (to church) to exchange old stories with other old gossips … they met friends and relatives on the way, or when they reached the county town, whom they enjoyed seeing … there then followed a meal or perhaps a reciprocal invitation, which led to one relative or another….’ But if that was the way it was for the old ladies, what did Sunday mean to ‘young girls, whose blood throbbed with the sweetest desire of nature!’ We can well understand their impatience, ‘they waited for each other at the start of the road they shared,’ they danced.

“Now, however, when the Tenth Day came around, ‘the men were left to the devices they always had:’ the old men went to the tavern, and they bargained. The young men drank and, deprived of their ‘lovely village girls’, they quarrelled. As for the women, they had nothing left to do in village. The mothers were miserable in their little hamlets, the daughters too, and out of this came their need to gather together in crowds. If the need for recreation is necessary because of moral forces… there is absolutely no doubt that village girls find it very hard to bear privations which are likely to prolong their unmarried state: ‘in all regions the pleasure of love is the greatest pleasure.'”

– from The Revolution Against the Church, From Reason to the Supreme Being, by Michel Vovelle, pp 158-159.

thrance•2h ago
I know the real goal of the republican calendar was to undermine the Church's power by making it so Sundays would fall at random days of the week, and also screw over the workers by leaving them with a worse weekend-to-week ratio.

However, all I ever read about this part of the revolution seems to indicate that people just didn't comply and went to church anyway on Sundays, and also didn't work that day. On that account, I feel likr your quote is kind of partisan. People wouldn't have been left lost and aimlessly drinking on their tenth day because of a lack of God, because they never quit going to church!

paulorlando•2h ago
Not sure I understand what you mean. At least, I thought that (most? all?) the churches were closed for the worst part of the French Revolution aftermath.

For example, the new state transformed Notre Dame and other Catholic churches into Temples of Reason, from which the new state religion, the Cult of Reason, would be celebrated. It didn't last long. Hard to create a new religion quickly. Maybe some echoes of recent history there.

thrance•2h ago
It was much more nuanced than that, and the vast majority of the French people stayed Christian during the period. Also, keep in mind the revolution was mostly a Paris thing, the rest of the country was left relatively unaffected at first.

https://en.wikipedia.org/wiki/Dechristianization_of_France_d...

paulorlando•16m ago
Is the difference "stayed Catholic" vs the churches had to close?
jacquesclouseau•5h ago
inb4 we still have the 8 hour workday
nancyminusone•5h ago
Sadly, the 100 day year never worked quite right.
thrance•2h ago
No but they had a clean year of 12 months, 30 days each (3 ten-day weeks) plus 5/6 holiday days at the end of the calendar (around the September equinox).

Also, the months were given names by a Poet, and the days had minerals, vertues or plants instead of Saints. The calendar itself was pretty cool.

Honestly, if they had 5 weeks of 6 days each instead of the 3 weeks of 10 days, I'd even call it the perfect calendar.

Snow_Falls•2h ago
Might I introduce you to visions of what could have been: https://en.wikipedia.org/wiki/Calendar_reform
linguistbreaker•4h ago
I hadn't heard of this and it's fun to think about.

It's 100,000 s/day as opposed to our current 86,400 s/day which is not far off.

Hours, however, were twice as long.

They had time pieces that displayed both together.

Swenrekcah•4h ago
Their seconds must have been about 864ms though, otherwise they day is more than 3 hours too long which would be very annoying for any kind of scheduling I’d imagine.
IAmBroom•3h ago
Yes. Obviously.

Or more to the point: since they had no use for milliseconds at that time, their milliseconds would have been 86.4% of standard milliseconds.

bonzini•8m ago
It also messes up the original proposal for defining the meter, which predated the revolution and was "the length of a pendulum with a period of 2 seconds" (i.e. the pendulum would be at its lowest point once per second). Which is ironic considering that the meter was also adopted during the revolution, though with a definition not based on the length of a pendulum).
hilbert42•4h ago
What about 90° per right angle and not 100°?

It made sense to keep some things like angle measurement and time as disruption was too great for very little practical benefit.

az09mugen•3h ago
Still France and French revolution context : https://en.m.wikipedia.org/wiki/Gradian
IAmBroom•3h ago
It's called a "gradian", and it's 1% of a right angle.

It's still used in some industries, where convenient.

kitten_mittens_•4h ago
If you’re interested in a what an analog clock in decimal time might look like: https://decimal-time.netlify.app/
az09mugen•3h ago
Ahah nice one, thanks for sharing !
thrance•3h ago
Slightly unnerving seeing seconds pass by 15.74% faster.
HPsquared•2h ago
Uncanny valley. Never seen a clock do it before.
wyett•2h ago
My thoughts too.
pavlov•2h ago
Feels like living in the future. Progress marches on faster than ever.

Honestly a brilliant marketing move by the French revolutionaries, just a few hundred years too early.

HideousKojima•1h ago
If they were truly revolutionary they would have gone for base 12 or 60 instead of 10
ucarion•2h ago
And every other month was named after a coup d'etat!
cafard•1h ago
As I habitually mention when the revolutionary calendar comes up, emacs calendar mode will give you the date with p-f. For what it's worth, today is Quartidi 4 Prairial an 233 de la Révolution, jour de l'Angélique. (Prairial I had heard of, jour de l'Angélique is news to me.)

[edit: corrected spelling of Quartidi]

nancyminusone•5h ago
Things that annoy me about the metric system: base-10 numbering system, a liter is not a cubic meter, and 'kilogram' is the base unit, not 'gram'.

That last one is what I have the biggest problem with. When you are doing anything with derived units, 'kilo' suddenly disappears.

kergonath•4h ago
> base-10 numbering system

Having decimal numbers, it’s the best solution. Otherwise you’re bound to make mistakes scaling things up or down.

> a liter is not a cubic meter

Well, it’s a dm^3, close enough ;) Conversion is trivial, 1 m^3 is 1000 l. A cubic metre is a bit large for everyday use, but it makes sense e.g. when measuring water consumption or larger volumes. The litre also had the advantage of being close to 2 pints, so it already made sense as a unit when it was introduced. Contrary to hours with 100s.

> 'kilogram' is the base unit, not 'gram'

Yeah, this one is perplexing. It’s an annoying inconsistency on an otherwise beautifully regular system.

GlobalFrog•4h ago
I don't understand your issue between gram and kilo gram: gram is the base unit and the prefix kilo, meaning one thousand just says that 1 kg = 1000 grams. It is exactly the same as meters and kilometers: meters is the base unit and 1 km = 1000 meters.
tokai•4h ago
I think they mean that the gram is defined as 1/1000 of a kilogram. With a kilogram having a definition based on physical constants.
jabl•3h ago
The kilogram is no longer defined by a physical artifact, fwiw.

Anyway, the point is the inconsistency in the system due to the kilogram being the base unit. So derived units are defined in terms of kilogram rather than gram. Say, the unit of force, Newton (N), is defined as kgm/s^2 and not gm/s^2). Or pressure, Pascal (Pa) which is N/m^2 which inherits N being defined in terms of the kilogram). And so on. Anyway, an annoying inconsistency maybe but doesn't really affect usage of the system once you get used to it.

DavidSJ•3h ago
In SI, kg is the base unit, and g is a derived unit.
selkin•2h ago
It’s an historical artifact, as it was easier to manufacture a reference kilogram than a reference gram.

Considering today we set the kilogram by fixing the Planck constant and deriving it from there, we can just divide each side of the definition by 1000 and use that as a base unit. Using kg as the base unit is completely arbitrary, as we can derive each unit of weight directly from the meter and the second, not from the base unit.

jl6•4h ago
Why is base 10 annoying?
nancyminusone•4h ago
Too few divisors of place values. The idea you would pick something that isn't evenly divisible by at least 3 or 4 was a mistake.

This one isn't metric's fault to be fair. That's just what you get for inventing numbers before inventing math.

Makes me wonder what would have happened if 'French numbers' in base 12, 36 or 60 were introduced at the same time.

People got used to working in octal.or hexadecimal in the past for computers, doesn't seem like it would have been as big of a change as you think.

tokai•4h ago
>evenly divisible by at least 3 or 4

Irrelevant with a decimal system.

chungy•4h ago
It's not irrelevant, you can choose something like 12 to make all your factors out of. It's a particular strength of working in feet and yards.
henrikschroder•1h ago
Except now you can't divide accurately by 5. Or 10.

You're making an argument from familiarity. Yes, a 12-base system using fractions works very neatly in a small human-sized domain, but it disintegrates into complete uselessness outside that domain. That's why you get ridiculousness as things being 13/64th of an inch, or that there's 63360 inches in a mile. It's unworkable for very large distances and very small distances. With a metre and standard prefixes, you don't need any conversion factors, and you can represent any distance at any scale with a single unit.

Quick, what's 11/64" + 3/8"?

Quick, which weight is bigger: 0.6lbs or 10oz?

IAmBroom•3h ago
Irrelevant if you are working with computers and digital equipment.

Highly relevant if you are using T-squares, compasses, and dividing calipers.

mfost•3h ago
It's just a matter of working with base elements that are divisible by 3 and 4 really.

So instead of buying 100cm planks, buy 120cm planks?

foobiekr•3h ago
Base 60 is genuinely the best option.
forty•2h ago
Don't you think base 10 was used simply because it conveniently matches the number of fingers of Humans?
nancyminusone•2h ago
Of course... But - look at your open hand right now. Count the number of segments on your 4 fingers - it's 12. You can even use your thumb as a pointer and count one handed.
empath75•2h ago
There's two reasons to use a measurement system -- one of those is for sort of every day work -- cooking, home carpentry and the like, and in that case, having something like the imperial system is nice, because you can divide things usefully.

The _other_ reason to use a measurement system is for doing _science_, and for that, having everything in base ten makes things _immensely_ easier, especially if you're working the math out by hand

henrikschroder•1h ago
> because you can divide things usefully.

Again, this is just familiarity. You think it's super neat that you can divide a cup of whatever by 2 or 3 or 4, but if I tell you to divide it by 5, you're gonna deflect and ask me "who does that?!?"

Imperial works neatly for a small domain of problems, and is useless outside that domain.

Metric is less neat in that small domain, but works equally well everywhere.

AStonesThrow•1h ago
Well no...

Firstly, we can divide a cup by 2, 3, and 4 in the kitchen because those are common measuring-cup sizes. Nobody is prevented from using a fractional size: if I divide a cup by 5 then I have 1/5th of a cup, nothing more and nothing less.

While 1/4th of a cup is 2 oz, and 1/3rd of a cup is 16 teaspoons, 1/5th of a cup doesn't divide evenly into a smaller unit and that's why "we don't do it", but there is nothing to stop the chef from using 9 teaspoons. [Or he can instinctively go up to 45mL on his graduated measuring cup, which almost always has both systems on it!] Teaspoons, tablespoons, ounces, cups, quarts and gallons are all inter-related multiples, and once you internalize it, you can convert like a boss.

While I'm sure it's lovely that metric measures divide by 2 and 5, that's all they divide by, so in terms of divisors, you've lost 3, 4, 6, 8...

So if it really is about dividing things usefully without resorting to fractions, then using a system that is nothing but multiples of 10 is a handicap, when we've had systems with lovely 12s and 16s with many different options for dividing them up.

But the metric people can simply chop up the measures even more finely and claim victory. For example, currency: it was in multiples of 16 or 8 which allowed for limited permutations. Decimalization chopped it into pennies, and we find 100 gradations in every pound sterling. All that did is make base-10 math easier for bean counters, and confuse people on the streets with a mystifying array of coinage. [Mental math indicates that it must increase the volume of coins per average transaction, as well.]

If a basic customary unit of length is an inch, many people can put two fingers together and estimate that on the human scale. But who can estimate or eyeball a millimeter?

Oh, and, have you ever found a nice British recipe in metric, shopped at your American grocery store, and prepared that in your American kitchen with your Fahrenheit range? You will eventually want to tip it all in the rubbish bin. Adam Ragusea suggests as much: https://youtu.be/TE8xg3d8dBg?si=SD8wLxD6ib6InLX4

henrikschroder•38m ago
> Teaspoons, tablespoons, ounces, cups, quarts and gallons are all inter-related multiples, and once you internalize it, you can convert like a boss.

"It's super easy if you're familiar with it!"

Yes, that is exactly the problem that you are unable to see.

chupasaurus•25m ago
> If a basic customary unit of length is an inch, many people can put two fingers together and estimate that on the human scale. But who can estimate or eyeball a millimeter?

If you'd grown with a metric system you could eyeball a centimeter with ease. Also comparing orders of magnitude different measures for estimation isn't fair, how precise would be your guess of a barleycorn?

cryptonector•32m ago
Er, `gram` most definitely is the base unit. Kilogram is what's handy for humans given how light a gram is.

EDIT: Yes, yes, SI defines the kg and then the g by reference to kg, but so what, notionally it's still the gram that's the base unit.

nartho•5h ago
I always think about what a cool adventure it must have been, for Pierre Méchain and Jean-Baptiste Delambre to roam for 7 years, go wherever they need thanks to an official letter, make calculations and come back successful to Paris. To think that they were only off by .2mm !
selkin•3h ago
“The Measure of All Things” by Ken Adler[0] is a good, extremely readable book about their adventure, which was indeed wild.

[0] https://en.wikipedia.org/wiki/Special:BookSources/978-0-349-...

frasermarlow•2h ago
Yes, this is a brilliant book, and well worth reading. Another other one in the same vein is "Longitude" by Dava Sobel: https://www.amazon.com/Longitude-Genius-Greatest-Scientific-...
BitwiseFool•4h ago
As an American, I finally relented and purchased a Metric measuring tape after the ordeal of trying to measure the dimensions of the rooms in my house. When it comes to interior decorating, trying to figure out how to evenly space items that are sized in feet, inches, and fractional inches is a nightmare. Imagine trying to space objects 2 feet 7½ inches long against a wall that is 13 feet 2 inches long. Now imagine this task with 80 centimeter long objects and a ~400 centimeter wall.

I am angry that IKEA's localization does not allow Americans to view dimensions in metric site-wide. You can still see dimensions in metric but those only appear on the pictures of some items. The webpage still converts all textual measurements to Imperial. You can't sort and search using metric values. IKEA designs everything in metric, using nice, even, whole numbers. Please let me see those. Seeing them converted to the nearest 32nd of an inch feels like vandalism.

lostlogin•4h ago
> I am angry that IKEA's localization does not allow Americans to view dimensions in metric

I’m not American and laughed at this.

Welcome to the other side. Also, here in New Zealand people seem to do everything in metric, except their height and the weight of their baby. Why?

remram•4h ago
As a Frenchman living in the US, my favorite Imperial units are the hand (3 hands to a foot) and the poppyseed (4 poppyseeds to a barleycorn, the shoe-size unit; 3 barleycorns to an inch). 10cm and 2mm.

People stop asking me to convert to Imperial pretty quick.

BitwiseFool•4h ago
Save your sanity, don't bother learning the conversion factors. Did you know that most of us don't even know how to convert between our own units? I invite you to go around and ask 'how many pints are in a gallon?'.

It took me an embarrassingly long amount of time to realize that there are four quarts in a gallon...

I have no such trouble with any SI unit. So with that, I will leave you with this!

"For of all sad words of tongue or pen, the saddest are these: 'The French were right again!'"

toolslive•2h ago
> Save your sanity, don't bother learning the conversion factors.

They were drilled into my brain when I was in primary school: 10, 100 and 1000.

nancyminusone•4h ago
The US doesn't and never has used the imperial system, as it did not participate in the unit reforms of 1824.

5 us gallons is about 4 imperial gallons.

remram•3h ago
I know that, but Americans don't and ask for "Imperial". No one has ever asked me for "US customary". Either way, I am using those units to be facetious more than compliant ;-)

In practice the volume units are a much bigger problem. I have not hit anyone with the "cubic hand" yet...

dragonwriter•4h ago
The US uses the US customary system, not Imperial. [0] US customary and Imperial share some units, and, confusingly, share even more unit names, but they are different systems.

[0] well, really, it uses metric with a redefined version of the old US customary system layered over it to prevent people from noticing, but...

BitwiseFool•4h ago
We've made an inconsistent and confusing system even more inconsistent and confusing. How apropos!
ahazred8ta•1h ago
In 1776 everyone was still using the Winchester System. https://en.wikipedia.org/wiki/Winchester_measure The UK didn't adopt the Imperial system until 1824-1826. Us Yanks have to suffer the indignity of our meager 473 mililitre pints.
ThePowerOfFuet•4h ago
>I am angry that IKEA's localization does not allow Americans to view dimensions in metric site-wide.

Change to the IKEA site of a different country (via what comes immediately after `ikea.com/`).

Snild•4h ago
It seems the Canadian site gives both sets of units: https://www.ikea.com/ca/en/p/brimnes-cabinet-with-doors-whit...

I guess they thought the mere sight of metric would offend the Americans. :)

Maybe the product ranges between the countries is close enough that the Canadian site is an alternative?

WillPostForFood•3h ago
Imagine trying to space objects 2 feet 7½ inches long against a wall that is 13 feet 2 inches long. Now imagine this task with 80 centimeter long objects and a ~400 centimeter wall.

You've made an artificially hard example (Ikea doesn't separate units, it is just inches).

What's harder, a 24" object on a 160" wall, or a 59cm object on a 4m 3cm wall?

Or to compare like for like (rounding & unified units), a 24" object on a 160" wall vs a 60cm object on a 400cm wall? Seems the same.

justinrubek•1h ago
That's part of the point, though. Ikea might not do separate units, but this is not an uncommon practice elsewhere. In the metric example I don't need rounding because I can trivially see 4m 3cm and know it's 403cm. With inches I'd have to do multiplication to handle mixed units.
hungryhobo•56m ago
but you have to do math to convert 13 foot 4 inches to 160 inches vs just moving decimals
lysace•53m ago
> Seeing them converted to the nearest 32nd of an inch feels like vandalism.

Malicious compliance.

As a non-American: I love it. ;)

bambax•4h ago
Here's a completely random anecdote: my mother often told me that her father, my grandfather, born in France in 1899, sculptor, draftsman and general maker of things, had a strong dislike of the metric system. He complained continuously that anything with round metric ratios was "ugly" and that beauty could only be found in more ancient measuring systems.

He died when I was 4 so it's not a first hand account, I'm not sure how much of it is true or what he really thought, but somehow it feels right.

The metric system is incredibly useful and practical (of course) but there's something rigid and unpleasant about it.

IAmBroom•3h ago
I know modern craftsmen* who lament the same. Being able to divide things in 2, 3, 4, 6, or 12 is mechanically more useful than 2/5/10 (the former being achievable by drafting tools more easily).

*Yes, it should be craftspeople, but that doesn't exactly sound like the same thing, and anyway all of them happen to be men.

Svip•2h ago
Nothing's stopping you from defining beautiful ratios and express the result in metric units, like ISO 216.[0] It feels like an odd complaint about the utility of the metric system, as if it is the only system; ratios aren't even units themselves!

[0] https://en.wikipedia.org/wiki/ISO_216

toolslive•3h ago
Still, wouldn't base 12 be better than base 10 ?
IAmBroom•3h ago
Pretty much everyone born from -2,500 BCE to ~1800 CE would agree, and a significant of those born since.
ahazred8ta•2h ago
https://dozenal.org/ The Dozenal Society of America would agree with you.
sham1•1h ago
Number bases are arbitrary. Like, base 12 certainly has interesting properties since it is a highly composite number, but a lot of the convenient representations can be achieved by using actual fractions instead of insisting on radix points/commas.

For example, 1/4 being 0.3 in base 12 can make certain computations easier (just as a 1/3 being 0.4_12 would), but again, what's wrong with 1/4 and 1/3 respectively.

Of course, things like duodecimal and base-6 are interesting to use, but at this point the convention is base-10 and it probably won't change for a while. It's kinda like the \pi Vs \tau debate, where even with all the elegance and easier pedagogy brought by the use of \tau as the fundamental circle constant, the existing convention does matter, and probably matters a lot more in general than the better alternative.

Of course, this also applied to the SI units. It literally took a major historical revolution for these units to be a) defined and b) getting used over the old units.