Why 10,000 BC?

Using this Chrome extension you can translate BC dates into any year numbering system (you can set the starting point yourself). But I recommend using Old Era – a 10,000 year long era that ended the moment the Common Era started.

Why 10,000 years? What’s so special about that number?

There are a couple of reasons. First, if you want a usable system, you want to convert dates in all of the historical literature into that system. But you don’t translate only years. You also need to be able to translate centuries and millennia. For example, 4th century BC is 97th century in the Old Era, and 2nd millennium BC is the 9th millennium of the Old Era. To have such simple and straightforward conversions you must use the same centuries and millennia that the Christian timeline uses. In other words, your era has to have a whole number of millennia. Here are some examples of possible era lengths in years:

3000, 4000, 5000, 6000, 7000, 8000, 9000, 10000, 11000 and so on.

Let’s look at a counter-example. What happens if you count from some non-round year, let’s say, 8564 BC? Because there is no correspondence between centuries and millennia of your timeline and those of the Christian timeline, you can’t simply change numbers of centuries and millennia. The best you can do in this case is to take the first and last years of any century and millennium and convert those. 

Using  8564 BC as the first year of your timeline you will have to say that 4th century BC is a century that started in year 8165 and ended in year 8264 of your era. And 2nd millennium BC is a millennium that started in year 6565 and ended in year 7564. The “Old Era” Chrome extension will show them as “8165/8264 century” and “6565/7564 millennium”. Obviously this is super inconvenient. That’s why you should choose an era that consists of a round number of years.

All usable timelines produce similar looking dates

One interesting consequence of using an era with a whole number of millennia in it, is that the last 3 digits of any year number are predetermined. They are simply a chronological number of that year inside its millennium. Here are some examples.

Caesar died in:

9 957 – since 10,000 BC,

6 957 – since 7000 BC,

3 957 – since 4000 BC,

and so on

The last 3 digits (…957) are always the same. And this is true for all dates.

My decision to put 10 millennia into the Old Era only affected the fist digit in every 4-digit year number. This means that the cost of a possible mistake on my part is extremely low. Let’s say you have learned a few dozen dates in Old Era and now you are as comfortable using Old Era dates as you are using BC dates, if not more. But then, a few years later you realise that using 10000 year long era was a mistake, and instead, that era should be only 7000 years long (for some unknown reason). All you’ll have to do is change the starting year in the settings of the extension and then get used to the new first digit of every year.

All of history before Common Era consists of 3 millennia which in Old Era can be described as 7000s , 8000s, and 9000s. 

In an era that starts in 7000 BC these millennia will turn into 4000s, 5000s, 6000s. You’ll have to get used to that, which will take you a few days, but you won’t have to relearn all the dates from scratch. Here are some examples of how some dates will change when you transition from one system to another:

9 957 -> 6 957  – Caesar dies,

9 511 -> 6 511 – Battle of Marathon

8 800 -> 5 800 – Trojan war 

7 400 -> 4 400 – the Great pyramid was built around that year

6 900 -> 3 900 – Unification of Egypt.

To use long eras you have to know Old Era year numbers

Secondly, let’s look at what happens if you use a very long era. Let’s say you want to count years from the Big Bang, which happened 13,8 billion years BC. You can type this number (13800000000) into the settings of this extension and you will see that year numbers become long and unusable. But what’s interesting is that the last 4 digits of any year are the same as in the Old Era. 

For example, while in Old Era Caesar died in 9957, if you count years from the Big Bang, you get the number 1379999_9957 for that year. And, of course, that works for any date. Let’s look at another example: Cleopatra was born in 9932 (OE) or in 1379999_9932 (since the Big Bang).

Because history before Common Era is contained in only a few millennia, you need year numbers with exactly 4 digits to describe all of it. Everything to the left of those 4 digits is useless.

For example, from unification of Egypt (the first historical event) in 1379999_6900 until almost the very end of that big era in 1379999_9999 the first 7 digits (1379999) don’t change. What’s the point of keeping them? Even if you keep them in texts, if you are going to actually use those big numbers, your attention will always be on the last 4 digits, because only those digits contain useful information. This means that one way or another you’ll be using the Old Era.

And this can be said of any era that is divisible by 10000. Let’s list some examples.

Caesar died in:

1379999_9957 – since the Big Bang

449999_9957 – since the beginning of planet Earth

19_9957 – since the beginning of human race (200,000 BC)

1_9957 – since 20,000 BC (the smallest era, other than Old Era, which is divisible by 10000).

9957 – in the Old Era.

You can memorize these sets of useless digits (to the left of Old Era dates) and then hide them by simply using Old Era. For example, I memorised these sets of digits: “1379999” and “449999”. Now, any time I want, I can attach them to any Old Era date in my mind. This allows me to say that I know history in the system that counts years since the Big Bang, and also in the system that counts years since the beginning of our planet. I just don’t need to always see those digits in texts. I’m OK with only seeing the last 4 digits of every year number.

Just like using any large era that is divisible by 10000 requires you to know Old Era dates, you can likewise reduce other large eras that are not divisible by 10000 to a small set of eras other than Old Era. 

For example, the last 4 digits in year numbers produced by era that starts in 106,000 BC will be the same as the 4 digits produced by era that starts in 6000 BC. Using an era that is 37,000 years long will be effectively the same as using a 7000 year long era, and so on.

It means that for all practical purposes, all the imaginary variety of starting points can be reduced to a set of just a few options:

3000 BC, 4000 BC, 5000 BC, 6000 BC, 7000 BC, 8000 BC, 9000 BC, 10000 BC.

Options 1000 BC and 2000 BC are excluded because they don’t cover enough history. 3000 BC covers almost all history.  For example, unification of Egypt (the first historical event) happened in 3100 BC, but that’s only an estimate. So, you can decide for yourself if 3000 BC should be included in this list. Either way, we have only 7 or 8 options.

You cannot pick anything in between those options (like year 8564 BC) because that will mess up your centuries and millennia. And while you can go beyond 10000 BC and use a larger era, you won’t get anything from it, just a bunch of useless digits that stay the same throughout history.

Now, given these options:

3000 BC, 4000 BC, 5000 BC, 6000 BC, 7000 BC, 8000 BC, 9000 BC, 10000 BC,

why wouldn’t you choose 10000 BC? It’s the most natural choice because we count in base 10. You can say that by the end of Old Era we’ve used up all 4-digit numbers and then we restarted the count. In the future we can repeat this pattern and restart year count every 10000 years: in the long run you’ll have to use some kind of modular system anyway, or else year numbers will become long and unusable. 

If you start the count, let’s say, from 4000 BC, you will count up to 4000 years and then restart the count which is just weird. Why not use up all possible 4-digit numbers before you restart?

Old Era is just the Christian timeline without the countdown

In general, Old Era can be thought of as an upgraded version of the Christian timeline. We use the same units of time (centuries and millennia from the Christian timeline). We only remove the backwardness of BC dates. Other than that we use the same system. Even the Old Era itself in its entirety is nothing else than another unit of time that comes from the Christian timeline. In the Christian timeline that period of time (10,000 BC to 1 BC) is called the 1st decamillennium BC. 

To drive home this idea consider following examples.

– On the level of centuries:

If Cleopatra was born in 9932 that means that she was 100 years old in AD 32. 

Since Augustus reigned in 9974 – AD 14, you can clearly see that he reigned for 40 years. 

– On the level of millennia:

Rome became a Republic in 9 492 and 2000 years later in AD 1 492 Columbus discovered America. 

Caesar died in 9 957 and 2000 years later in AD 1 957 the first artificial satellite (Sputnik-1) was launched starting the Space race. 

These are completely unrelated events but this is not the point. The point is that it is the same system. 

If you ever wondered what history would  feel like if you didn’t have to always pay attention to how ancient things are and instead focused on the progression of time, just use the Old Era. 

At least try using it as you would use different time formats. For example, you can say that 3:00 PM is 15:00, and 7:00 PM is 19:00. Think of Old Era as a second system that you can use right now. You can say that Caesar died in 44 BC or 9957 OE. 

To use this system you don’t need an official calendar reform. There is no need to worry about how many people use this new system. Don’t think of it as “converting” to another system as if you are converting to some new religion. Just use both systems simultaneously and see for yourself which one is better. And don’t assume that you know the answer before you’ve mastered the Old Era. 

S&E system: year numbering system of the future

Have you ever wondered how people will count years in the far future? Like millions of years from now. One way to think about it is to say that it’s not our problem so let’s not think about it. But that’s kind of silly. For one thing, we are at the very beginning of history, a perfect time to design a year-numbering system that would work nicely for as long as planet Earth is habitable. That’s about 500-1000 million years until the Sun boils oceans on Earth. 

Once nobody lives on Earth, a year numbering system based on Earth year will lose much of its relevance, and will only be used for studying history of Earth.

Secondly, we have all the information needed to design such a system. We may not know if our civilisation survives the next hundred years, but we know for sure what year it will be, for example, one million years from now if we don’t change anything (1,002,022). Or ten million years from now (10,002,022). 

Examples of long year numbers

Let’s look at some examples to see what long year numbers will look like in texts in the distant future. For that we will use one Wikipedia page and move the beginning of the Common Era into the past, first by 10,000 years, then by 100,000 years, then by 1,000,000 years. Pay attention to year numbers.

Adding 10,000 years to the Common Era (year numbers are basically Holocene Calendar or Human Era dates)

Adding 100,000 years to the Common Era

Adding 1,000,000 years to the Common Era

I have more screenshots with year numbers like 10,002,009 and 100,002,009 but there is no need to add them here. You get the idea. Texts become filled with numbers. And a lot of digits don’t add new information. The same digits are repeated in multiple dates.

You may think that maybe 5-digit years are tolerable. Maybe. But think about it this way: what does the first digit “1” mean in, say, year 12,009? It just means that this year belongs to the second decamillennium. This digit changes once every 10,000 years, yet it will ‘infect’ lots and lots of texts for thousands of years without adding any useful information. Can’t you just know from the context that we are talking about the 2nd decamillennium? Or maybe we could mention this fact one time on the page and then just use 4-digit numbers?

Using 5-digit numbers is like insisting on writing “CE” (or “AD”) next to every year regardless of whether it actually resolves any ambiguity or not. Here is an example of what I’m talking about:

Using 5-digit year numbers is as stupid as adding “CE” to every single CE date

Long year numbers are not practical

It’s hard to believe that people, or whoever will live on Earth in far future, will just casually use such long year numbers in their everyday lives. I think they won’t use them even in history books. Just like you may sometimes write “22” instead of “2022”, year numbers in history books will be shortened. This will happen either officially or unofficially. Regardless, such shortening will result in Common Era being effectively split up into multiple finite eras. 

This isn’t something new. We restart numeration of some units of time already. Just not years. We repeat names (and numeration) of months every year. Day numbers in each month start anew as well. If I told you that July 2022 is month number 24,259 of the Common Era, that would be useless information, because we don’t use months like that. We mostly look at any month in the context of a year it is in. If I told you that some event happened 254 months ago, that would be just weird choice of units of time. Likewise, saying that July 19 is day number 200 from the beginning of this year is not particularly useful.

At some point in future, measuring time in absolute years would start to feel like measuring distances between cities in nanometres. Too much precision. You’d want to use year numbers only within a context of some finite era and start numeration of years in each era anew. This way year numbers will always be small. And in some cases to avoid ambiguity you’d mention which era you are talking about by using labels, like so: “2022 E2”.

How long will these eras be? The number that makes the most sense, at least in my mind, is 10,000 years. This number ensures that years that people use in their day to day lives (and even in history books) will always be as short as possible. You will only have a 5-digit year number once every 10,000 years (actual year 10,000). All other year numbers will have 4 digits or less. At the same time 10,000 years is such a long period (for comparison there has been only 5000 years of recorded history up until now), that there will be no danger of mistakenly confusing dates from two different eras. In some cases where you think an ambiguity may arise you will simply use era labels (E1, E2, E3, etc.), just like we currently use BC/AD (BCE/CE) labels. But most of the time you’ll be using 4-digit numbers without any labels.

The eras can have numbers. For example, Old Era is the first era. We live in the second era. And right after year 10,000 CE the third era will begin with year 1 E3.

Once you have a lot of those eras you can group them as well and restart the count of eras every so often. For example, 100 eras each consisting of 10,000 years add up to one million years. We can make groups of 100 eras, so that the era that follows era 100 is era 1 again only belonging to the next million years.

Naming the eras

We have now two units of time for grouping years: decamillennium (or era) and million years. Let’s give them better names. Imagine that history of our civilisation is like a TV show. It has seasons and episodes. So, let’s say, that one million years is a Season. And decamillennium (or era) is called an Episode. Each Season contains 100 Episodes. Each Episode contains 10,000 years.

And the entire year numbering system may be called just “Seasons and Episodes” or “S&E system”. We live in year 1.2.2022 (season 1, episode 2, year 2022). It may even be written as 2022 S1E2. Or, since we only have one Season for now, just 2022 E2.

Let’s compare the notation for the same years in S&E system, Human Era and Common Era.

1.1.11 HE10,000 BCE
1.1.22 HE9999 BCE
1.1.33 HE9998 BCE
1.1.99999999 HE2 BCE
1.1.1000010,000 HE1 BCE
1.2.110,001 HE1 CE
1.2.202212,022 HE2022 CE
1.2.1000020,000 HE10,000 CE
1.3.120,001 HE10,001 CE
1.100.100001,000,000 HE990,000 CE
2.1.11,000,001 HE990,001 CE
2.1.21,000,002 HE990,002 CE
500.100.10000500,000,000 HE499,990,000 CE

You only mention Seasons and/or Episodes if there is ambiguity that needs to be resolved. Also, you may use seasons without anything else, just like you can use years without mentioning months or specific days. Or you can use Season and Episode without mentioning years, just like you can say “July 2022” without mentioning specific day of that month. If you know what Season you are talking about, you can use Episodes without mentioning the Season all the time, just like you can use months without mentioning the year they belong to. And, as I have said already, most of the time you’ll just be using 4-digit numbers without specifying Seasons or Episodes they belong to.

Don’t take this too seriously

Most of what I’m talking about here will not be useful for thousands of years. Some features of the real year numbering system of the future may end up being completely different from how they are described here. And there is no rush for us to define all of the characteristics of the system right now. For now, you should use S&E system only as a framework for thinking about year numbering system of the future.

What characteristics of this system may end up being different in reality? First of all, the names of time units. I don’t insist that proposed units of time should be called Season and Episode. It’s just that I couldn’t come up with anything better. But those periods of time need to have some names (even if those names are temporary) so we can talk about them.  If you don’t like those names you can use “Super era” and “Era” instead. 

Secondly, the numbers of episodes may end up being different from the numbers I gave them. Some people may ask, what if in the future we find out that history started earlier than 10,000 BC ? That’s a silly question, by the way. Others may say that we should count time not from the beginning of history, but from something else, like beginning of planet Earth or from the Big Bang. The good news is that we have tens of thousands of years to think about it. Right now we have only two Episodes containing recorded history: Old Era and Common Era. I like to think that Old Era is the first Episode, and Common Era is the second Episode. But those numbers exist only in my head. Likewise you can assign any numbers you want to those Episodes. The year numbers inside them won’t change. For example, Julius Caesar would still be murdered in 9957, whether you think the Episode containing that event is number one, minus one or something else. 

It would be nice if by year 10,000 CE people decided that the next era would be called just Third Episode. Then they’d have Episodes that go like this: OE, CE, E3, E4, E5, and so on. First two eras would have implicit numbers. There is no need to explicitly rename them to E1 and E2. On the other hand, it would be very easy to rename them in electronic texts programatically. 

But if by 10,000 CE people are still not sure how to number the Episodes, they may just come up with some name for the next era. They can, for example, name it New Era (NE). This can be done over and over for a few subsequent Episodes. Numbering Episodes will become important only when you have a bunch of them. That’s why I say that we have tens of thousands of years to come up with a proper way of numbering them.

As for the Seasons, obviously, we won’t really need to use them for about one million years.  

The most important thing is to actually restart year count after 10,000 CE. Some kind of official calendar reform will be needed for that to happen. If that is not done, the year numbering system will be messed up forever. But we have almost 8000 years to prepare this reform.

Usefulness of S&E System

Although this system may seem useless for us, people living in the 21st century, there is actually a use case for it. You can use it to see by comparison that not everything is OK with the Christian timeline. The Christian timeline was not created to present history in the best possible way. It messes up how we perceive ancient history, and it will create a mess in the future if nothing is done about it. 

Once you understand the flaws of the Christian timeline you will see a concept like Old Era in a different light.

You wouldn’t see it as something weird or unnecessary. Instead, you’d see it as making total sense. Because in the long run you want to use a modular system anyway.

If you are not familiar with the concept of S&E system, you may look at the picture above and think: “OK, I see that you replaced the countdown with a system where year numbers increase with time. But why is the history still divided into two parts?” The answer to this is that there will be many more similar divisions in the future, and there is really nothing special about this first division.

Old Era will help S&E System become a reality

To make sure S&E System is used in the far future, the most important thing is to restart year count after 10,000 CE. If it is done once, it will likely be done every 10,000 years. We can increase the chances of the calendar reform in 10,000 CE by simply using and popularising Old Era. 

I don’t want you to think about using Old Era as some kind of sacrifice on your part. You don’t use it so that something good happens in the future. You use it for your own benefit simply because using it is much better than counting years of history backwards. Nevertheless, popularising Old Era is the best thing we can do to increase the chances that our year numbering system will finally be fixed. Old Era sets a precedent. If you use Old Era, you know that there has been one restart of year count already.

Even if right now we could somehow get all the countries in the world to come to an agreement to restart year count after 10,000 CE, that agreement may not mean much almost 8000 years from now when it’s time to take action. 

But if we popularise the concept of Old Era to the point that it is basically a mainstream way of looking at history, then somewhere around year 10,000 CE it will be super easy to make the needed change. And remember, we have almost 8000 years until it’s too late.

Formulas for converting dates BC(BCE) into Old Era dates

In this article I’ll show you most of the formulas I use in my Old Era Chrome extension for date conversions between Christian timeline and the Old Era timeline.

If you haven’t installed the extension yet, you can do it here.

Precise translation of years

To translate any year BC into an OE year I subtract it from 10 001. The formula is: 10 001 – x

To see why this is, let’s visualise OE dates next to the corresponding BC dates:

BC and OE dates form pairs (1 and 10000, 2 and 9999, 3 and 9998, etc), and the sum of each pair is constant and equal to 10 001. That’s where the number 10001 comes from in this formula: 10 001 – x

For example, Caesar was murdered in 44 BC. In OE that would be (10 001 – 44) 9957.

Imprecise translation of years

Sometimes I can use formula 10 000 – x though. I call it imprecise translation. Let’s take for example the first historical event, the unification of Egypt, that happened, according to some historians, in 3100 BCE.

If we translate this year with the precise formula, we will get (10 001 – 3100) 6901. The ‘1’ at the end creates an impression that we are talking about a precisely dated event even though, of course, the original year 3100 BCE was a rough estimate. It would be better if we could convert 3100 BCE to year 6900 instead.

In such cases I use the formula: 10 000 – x

It is applied to round years like 3100 BCE. Sometimes to years like 2175 BCE. Basically if a year ends with 0 or 5 I may use imprecise translation.

But I have to be careful with imprecise translation. First, if a BCE year is round it doesn’t necessarily mean that it is not precise. For example Egypt was annexed by Rome in 30 BCE. That is a precisely known date even though the year is round, so it should be translated precisely and become the year 9971.

Second, there are cases when a date is both round and imprecise, but I still translate it precisely. For example it is said that Caesar was born circa 100 BCE. But it doesn’t mean that since historians didn’t know the precise date, they just picked a nice and round one. Actually, there are a couple of hypotheses of when he might have been born, one suggesting Caesar was born in 102 BCE, another suggesting he was born in 100 BCE. That means that he was born either in 9899 or 9901. With imprecise translation we’d get year 9900 for his birth, which is the same as year 101 BCE and does not agree with any of the two hypotheses.

Third, a lot of the times I translate years precisely just to not cause a mess. For example if some person was born in some year BCE that is round and probably not precisely known, and I translate that date imprecisely, effectively shifting it by one year, that may change his age that is usually mentioned in the article as well. Also, if I shift his year of birth I’d better be consistent across multiple articles that may mention this person.

For these reasons I tend to translate birth-dates precisely even if they are not precisely known.

A lot of times I use precise or imprecise translation based on my intuition. Also, the less I know about some particular part of history, the more I tend to use precise translation.

What to do, if you think I made a mistake by translating a particular date imprecisely while I should have translated it precisely or vice versa? There are two things you can do.

You may tell me about it, and if you convince me that I made a mistake, I’ll fix it.

If you don’t want to rely on my judgment and you are OK with having all the years translated precisely, just select ‘always translate years precisely’ in the pop-up menu of the extension. In this case you’ll have a lot of years ending with 1s, like year 6901.

Translation of millennia and centuries

Everything is much simpler with millennia and centuries. There is only one way to translate them.

For millennia the formula is: 11 – x

For example, 2nd millennium BC is (11 – 2) 9th millennium.

For centuries the formula is 101 – x

For example, 4th century BC is (101 – 4) 97th century.

Translation of decades

When it comes to decades, you should know that unlike years, centuries and millennia, decades BCE and decades OE don’t match perfectly. They are kind of shifted relative to each other. Let’s take for example 520s BCE:

You may say that 520s BCE correspond roughly to 9470s OE. You can use the formula, 9990 – x to translate each decade this way. But there is a problem with this approach.

A lot of times you’ll see phrases like ‘early 520s BCE’ or ‘late 520s BCE’. If I just translate this decade to 9470s, I’ll need to somehow convey to the readers that although they see the phrase ‘early 9470s’, they should mentally exclude years 9470 and 9471 from that decade. And when they see the phrase ‘late 9470s’, they need to include years 9480 and 9481.

Also sometimes an article on Wikipedia may mention some event X that happened in 520s BCE. If I don’t know much about that part of history I would start wondering what if that event actually happened in years 521 and/or 520 BCE -or 9480 and 9481 after translation – and in this case the event would not belong to 9470s.

In every such case I would have to conduct a small investigation about the event X. So I came up with a solution that solves all these problems:

I call it Christian decades. Instead of trying to find the closest OE decade that will never match with the BCE decade perfectly, I use the BCE decade itself, translating it precisely, as a range of years.

It may look crazy for the first few seconds you look at it, until you realise that the same pattern repeats for every decade. The first year of any decade ends with ‘2’, and the last one ends with ‘1’. For example, 9902/11, 9912/21 and so on. And so you can get used to it pretty fast. If the decade touches two centuries I write it down without shortening the last year: ‘9492/9501 decade’.

The only two weird decades are 0s BCE or 9992/10000 that has only 9 years in it, and the very first year of the Old Era that is a ‘decade’ containing only one year. The latter is never used in actual articles on Wikipedia, though.

It is probably useful to note that this ‘weird’ notation I use for decades is not and intrinsic feature of the Old Era. Let’s say you are a historian and you are writing a history textbook that uses OE dates. If you create your text from the top of your head (not translating someone else’s text) you can use decades like 9470s and they would mean exactly what one would expect when looking at them (in our example 9470s would mean years from 9470 to 9479).

It is only when you translate a text that originally used BCE dates that you have to translate decades as ranges of years. This approach ensures that you convey exactly what the original author of the text meant by using a specific BCE decade.