Let's stop counting centuries

Also, when they switched things in 1582:

https://www.britannica.com/story/ten-days-that-vanished-the-....

> The most surreal part of implementing the new calendar came in October 1582, when 10 days were dropped from the calendar to bring the vernal equinox from March 11 back to March 21. The church had chosen October to avoid skipping any major Christian festivals.

The century in which the switch occurred (which was different in different countries) was shorter than the others. As were the decade, year, and month in which the switch occurred.

The "original" Julian calendar was indifferent to year number systems. The Romans typically used the consular year, although Marcus Terentius Varro "introduced" the ab urbe condita (AUC) system in the 1st century BC, which was used until the Middle Ages. From the 5th to the 7th century, the anno Diocletiani (also called anno martyrum) after emperor Diocletian was used primarily in the eastern empire (Alexandria), or the anno mundi (after the creation of the world). It was Dionysius Exiguus in the 6th century, who replaced the anno Diocletiani era with the Anno Domini era. His system become popular in the West, but it took a long time until it also was adopted in the East. Its application to years before the birth of Christ is very late: we come across it first in the 15th century, but it was not widespread before the 17th century.

All these systems used the Julian system for months and days, but differed in terms of the year and (partialy) in the first day of the year.

The calendar goes from 1 BC to 1 AD, there is no year 0.

Have a read of this, it’s not how you think it is. https://www.historylink.org/File/2012

These are ones that are actually used, not just ones I made up. Sorry that wasn't more clear. I really hate conversation on this site.

And while we are at it, Tim Apple

Just to make sure I understood this, that would be used as "17th settecento" to mean 1700s right?

(This Xth century business always bothered and genuinely confused me to no end and everyone always dismissed my objections that it's a confusing thing to say. I'm a bit surprised, but also relieved, to see this thread exists. Yes, please, kill all off-by-one century business in favor of 1700s and 17th settecento or anything else you fancy, so long as it's 17-prefixed/-suffixed and not some off-by-anything-other-than-zero number)

> I think that's good, because it helps you realize that categorizing art by century is kind of arbitrary and meaningless

no it won't lol, people will pay just as much through the new dating system as they would through the old.

Agreed. The haiku is “18th century art” as that’s when it was first invented. So it’s either a uselessly broad category, or an indefensibly Eurocentric one.

You can change the world if you make it easier to meet a need enough people have. Persuading everyone they're holding it wrong is not that.

Re temp, I’m glad we use F for daily life in the USA. The most common application I have for temp is to understand the weather and I like the 0-100 range for F as that’s the typical range for weather near me.

For scientific work I obviously prefer kelvin.

Celsius is nearly useless.

It’s been tried. The “rational” calendar reform was something of a failure.

I’d say more sensible. It’s always weird to me to use the number 17 to talk about years that start with 16. Makes more sense to just say the 1600s.

Asking me to stop using my preferred convention is tantamount to 'reprogramming' me.

Or better yet just year 0, why not? Do we say the 80s start in 1981?

Then what is the last year of the first century BC? 2 BC? Now there's an off-by-2!

Do you also count the first decade of your life from January 1st of the year before you were born?

No, jesus was born in 1AD

“Half one” is archaic English, and common German, for 12:30. Similarly “my 27th year” just sounds archaic to me: I wonder if you went through a bunch of 19th century writing if you’d see ages more often be “Xth year” vs “X-1 years old”.

There may be something cultural that caused such a shift, like a change in how math or reading is taught (or even that it’s nearly universally taught, which changes how we think and speak because now a sizeable chunk of the population thinks in visually written words rather than sounds).

That's not really indexing from 0 though. It's just rounding the amount of time you've lived down to the nearest year. You get the same number, but semantically you're saying roughly how old you are, not which year you're in. This becomes obvious when you talk to small children, who tend to insist on saying e.g "I'm 4 and a half". And talking about children in their first year, no one says they're 0. They say they're n days/weeks/months old.

In an indirect manner, we do mark having lived the 27th year in the following forms, we just don’t say it exactly the way you phrased it:

1. On your 26th Birthday, when you say you turned 26 what it means is that you have now lived 26 years. People generally understand this, even if they are going to be spending the next year saying they are 26.

2. It is not uncommon for people to demarcate their age on their birthday in revolutions around the Sun, as a kind of meme. “I’ve now traveled around the Sun twenty-six times.” or something like that, when reflecting on their lives on their Birthday.

The colloquial usage is our legally-defined age. A shortcut for our laws to take, the age-gating ones anyway. It hasn’t replaced our cultural understanding of what the first year of our life actually was.

I think of the age number "practically" as the number of "birthday celebrations" I have experienced, excluding the actual day of birth. That's the same as the amount of completed years I've lived on this earth, and one less than the year I'm living in, because that year is not yet completed. (Except of course on birthdays)

But I think this also illustrates just how averse our culture is to using zero-indexing in counts: The age number absolutely is zero-indexed - a baby before before the first birthday is zero years old. But no one calls it like that, instead we drop the year count entirely and fall back to the next-largest nonzero unit, i.e. we say the baby is so-and-so-many months old. And for newborns not yet a month old, we count in weeks, etc.

I think, culturally, it's not that surprising as this method of counting is older than the entire concept of "zero". But I think it shows that there is little hope of convincing a large number of non-nerd people to start counting things with zeros.

I agree, that was my point.

And so is the first century of the zero-indexed calendar.

> On your sixth birthday we put a big 5 on your cake and call you a 5 year old all year.

If you are going to be that pedantic, I would point out that one only has one birthday.

(Well, unless one's mother is extremely unlucky.)

birthday != date of birth

“Birthday” really means “anniversary of the date of birth”.

The number we put on the cake represents the number of "years old" (i.e. the number of birthday anniversaries) not the number of birth days someone had (obviously). Zero year-olds are 0, one year-olds are 1, ...

> Sure, but no one ever uses that phrasing after you turn one.

Heck, few people say anything about 'the first year of life' even when talking about someone that young. It is too imprecise, because things change so rapidly. In my experience the most common convention is to use months to describe age before someone turns 2.

What? No. When you are 0, it is your first year. When you are 21, you have begun your 22nd year. In the US you are legal to drink in your 22nd year of life.

You are correct that nobody says "22nd year" in this context, but nobody says "21st year" either. The former is awkward but the latter is just incorrect.

> In "figure of speech", or conventual use, people start drinking in their 21st year, not their 22nd. In common parlance, they can vote in their 18th year, not their 19th.

That’s not the case, though. They can vote (and drink, in quite a few countries) when they are at least 18 years old, not when they are in their 18th year (who would even say that?)

People are 18 years old (meaning that 18 years passed since their date of birth) on their 18th birthday. There is no need of shoehorning 0-based indexing or anything like that.

> Most will say yes.

Most people say something stupid if you ask tricky questions, I am not sure this is a very strong argument. Have you seriously heard anybody talking about a child’s “5th year of development”, except maybe a paediatrician? We do talk about things like “3rd year of school” or “2nd year of college”, but with the expected (1-indexed) meaning.

> So perhaps it's logical to count from zero when there's no digit in the magnitude place, because you haven't achieved a full unit till you reach the need for the unit. Arguably a baby at 9 months isn't in their first year as they've experienced zero years yet!

It’s really not. To have experienced a full year, you need a year to have passed, which therefore has to be the first. I think that’s a cardinal versus ordinal confusion. The first year after an event is between the event itself and its first anniversary. I am not aware of any context in which this is not true, but obviously if you have examples I am happy to learn.

> It's unsatisfying, but solves the off by one errors, one of the two hardest problems in computer science along with caching and naming things.

Right. I know it is difficult to admit for some of us, but we are not computers and we do not work like computers (besides the fact that computers work just fine with 1-indexing). Some people would like it very much if we counted from 0, but that is not the case. It is more productive to understand how it works and why (and again cardinals and ordinals) than wishing it were different.

This is an instance of the general problem that a path of lenght n has n+1 nodes

I don't think it is a mistake for Lua. The convention to zero-index arrays is not sacrosanct, it's just the way older languages did it (due to implementation details) and thus how people continue to do it. But it's very counter-intuitive, and I think it's fair game for new languages to challenge assumptions that we hold because we're used to past languages.

Human Era. There is a Wendover Productions video about this. They also sell a calendar.

Oh you're right, I tripped up. "The last quarter of the second millennium BC" means about minus 1250 to minus 1001.

I often get excited by some discovery sounding a lot older than it actually is, for reasons like this.

I thought the article was going to argue against chunking ideas into centuries because it's an arbitrary, artificial construct superimposed on fluid human culture. I could get behind that, generally, while acknowledging that many academic pursuits need arbitrary bins other people understand for context. I did not expect to see arguments for stamping out the ambiguities in labellibg these arbitrary time chunks. Nerdy pub trivia aside, I don't see the utility of instantly recalling the absolute timeline of the American revotion in relation to the enlightenment. The 'why's— the relationships among the ideas— hold the answers. The 'when's just help with context. To my eye, the century count labels suit their purpose for colloquial usage and the precise years work fine for more specific things. Not everything has to be good at everything to be useful enough for something.

Array indexes start at 1 by default, instead of 0.

You ought naught to propose such noughts!

I wonder at what point we can just assume decades belong to the current century. Will "the twenties" in the US always primarily mean Prohibition, flappers, and Al Capone or will it ever mean this decade?

"17something...ish" is enough to answer (or at least make a high confidence guess at) the original question (was the American Revolution contemporary with the enlightenment?)

For that matter, a lot of historical dates we consider important are only important to us because A) we're westerners and B) we got them drilled into us by textbooks and classes.

The remaining majority of the world (the west is a minority) sincerely couldn't care less about the American or French or Industrial Revolutions or Columbus (re)discovering America or the Hundred Years War or the Black Death or the Fall of Rome or whatever else.

Kind of like how we as westerners generally couldn't care less about Asian, African, Middle Eastern, Indian, or Polynesian histories.

The culture we grow up in and become indoctrinated by determines what is important and what is not.

And just so we're clear, this bit of ignorance is perfectly fine: Life is short, ain't nobody got time for shit that happened to people you don't even know who lived somewhere you will never see.

America was a backwater at the time and therefore the best place to experiment with European enlightenment ideals. Which it did, and was a direct factor in the French Revolution. I also learned about numerous revolutions in Latin America from Mexico to Bolivar to San Martin over the early 1800s.

The events that directly affect the modern world should be covered in school. I’d say revolutions that created large modern states would be among them.

Swede here. Both the American an the French revolution were taught when I went to school in the ninth and tenth decades of the twentieth century. As GP points out, they're both fairly significant events that had side effects relevant even to us up here.

I would be extremely surprised if Sweden was unique among European nations in this regard.

Why not learn it anyway. Broader 'bildung' is a lifelong pursuit.

I grew up in Scotland. We studied American History in school. In fact we didn't study English History, except as it pertained to Scottish History, so to this day I'm hazy on Magna Carta, turbulent priests and so on.

I didn't make the convention. The 17th century started on January 1, 1701 and ended on December 31, 1800.

That's because the purported year of the birth of Christ was the "first year of the lord", or AD 1, and that's when the first century started. In turn that's because at the time Latin had a word for nothing but not a word for zero, so you couldn't count years starting at zero.

That also means that those old enough to have partied on December 31, 1999 were technically partying for the beginning of the last year of the second millennium.

I don't think they said ten hundred for the year 1000 either. I do use the twenty a for individual years though.

no, that part was crossed out as a joke (hence my attempt to add '~' before and after the crossed out section)

There are a lot of shibboleths and pointless conventions in the world. Flutists are called "flautists" because classical musicians aspire to be Italian, and if you don't pretend to be Italian too you'll embarrass yourself. Minute hands were originally long because they pointed to an outer dial of minutes, while hour hands were distinguished by being decorated, but now being slightly longer is just a stylization that means minute hand (even though "minute" means "small") and we have two pointers using the same dial for different enumerations, one without the relevant numbers and distinguished by fractional differences in its width and length. British English spellings are substantially French, and this is perpetuated as a matter of national pride.

Like the word shibboleth, these examples are all kinds of language. Even the clock hands are a sort of visual language. Nth century is another language element. The conventions make outsiders stumble, but for insiders they're familiar and shedding them would be disturbing. Over time they become detached from their origins, and more subtle and arbitrary.

In programming we have "best practise", which takes good intentions and turns them into more arbitrary conventions. These decisions are unworked again later by people saying "no that's dumb, I'm not going to do that", even if it is "how we do it" and even if learning it is a sign of cleverness. We have to be smart to learn to do dumb pointless things like all the other smart people.

Is this good? Keeps us on our toes, maybe? Or keeps us aligned with bodies of knowledge? I think it's definitely good that we have the force of reformist skeptics to erode these pointless edifices, otherwise we'd be buried in them. But new ones are clearly being built up, naturally, all the time. Is that force also good? Alright, yes, it probably is. Put together, this is a knowledge-forming process with hypothesises (I don't like using Latin plurals, personally) and criticisms, and it's never clear whether tradition or reform is on the dumb or overcomplicated side: it remains to be seen, as each case is debated (if we can be bothered).

> This is like asking to simplify basic math for people who can’t be bothered to learn long division, thinking this will somehow allow them to do calculus.

Oh dang, you kinda sorta had me until here. This sways me towards @Perseid’s point. :P Math education is full of unnecessary mental friction, and it pushes lots of people away. We know that finding better, simpler ways to explain it does, statistically, allow more people to do calculus. Long division is a good example, because it’s one of the more common places kids separate & diverge between the ones who get it and the ones who don’t, and there are simpler alternatives to explaining long division than the curriculum you and I grew up with, alternatives that keep more people on the path of math literacy.

We can see similar outcomes all over, in civil and industrial design, and in software and games, from cars to road signs and building signs to user interface design - that making things easier to understand even by small amounts affects outcomes for large numbers of people, sometimes meaningfully affecting safety.

The numbering of centuries is admittedly a simple thing, but maybe it actually is unintentionally elitist, even if you don’t think condescendingly, to suggest people shouldn’t complain about a relatively small mental friction when having to convert between century and year? Yes most educated people can handle it without problems, but that doesn’t tell us enough about how many more people would enjoy it more or become educated if we smoothed out how we talk about it and make it slightly easier to talk about history. This particular example might not change many lives, but it adds up if we collectively improve the design of writing and education traditions, right? Especially if we start to consider the ~20% of neurodivergent people, and ~50% of less than average people.

> They do it because they never bothered

Why should people have to bother, if it’s not necessary? Your argument that some people are lazy might be deflecting. Is there a stronger argument to support the need to continue using this convention? Being able to read old history might be the strongest reason, but why should we waste energy and be okay excluding people, even if they are just lazy, by perpetuating a convention that has a better alternative?

We don't need to refer to the third millennium as a whole right now, being in the first part of it. And by the time people need to refer to the 2000s, they will no longer have a reason to reference the 2000s.

You can also refer to, in speech, the twenty-hundreds, without ambiguity; I suppose, if you want it more compact in text, you could always write the 20-00s.

Not my problem, that can be fixed by a future generation of pedants. It'll be good enough for 50 years or so.

I'd agree to the extent that it sounds kind of twee and affected, but what would you use in its place?

And there is a year zero in the ISO 8601:2004 system, the interchange standard for all calendar numbering systems (where year zero coincides with the Gregorian year 1 BC; see conversion table). [via Wikipedia]

I don't have a good solution for that. Perhaps we're finding out why people have come up with weird terms like "naughts" or saying "aught-five".

> Citation heavily needed

I'm not going to give you any proof of this, because I know you've seen it, but I think I just wasn't very clear on what I meant here.

I'm talking about PRs that fix a typo in the docs, or tweak confusing wording. You know the ones I'm talking about, the ones that get merged immediately because it's clearly just better

"the current practice may not be perfect but has obviously stood the test of time"

has it stood the test of time? or is just an arbitrary choice that no one has bothered to change?

I'm sorry, it just seems like we're looking at spilled milk in the middle of the room saying, "well, it's been here since I walked into the room, obviously it's supposed to be here?" no we can just clean it up, no one's going to stop you

it's actually super, super easy to change this: you just starting using the new term. You don't even need to get anyone else on board, everyone understands what the new term means (this isn't even like inventing a new word, it's just a rephrasing that's just easier for the speaker & listener).

The goal isn't to get everyone to switch overnight. That's not how conventions are created nor how they spread. You just start doing the thing if it's useful to you. Whether it spreads beyond that is not up to you.

My takeaway from the post is simply: hey, if you find this confusing, here's a much simpler way you can talk about it! I am personally going to start using this, and I am going to get immediate benefits from this, and so are my readers. That's it, that's all it takes.