Decades, centuries and millennia


Blame it on DennisJanuary 1 is NOT the start of a new decade. To the CBC and the other arithmetically-challenged media who insist otherwise: it isn’t. You just don’t understand how to count to 10. No matter how you spin it, 9 years is not 10.

And even if it was, starting or ending a decade or any other period of time has no magical significance. Neither history nor culture, neither politics nor science work along calendrical timelines and our own calendar is an arbitrary construct for convenience only. But back to the numbers. It all comes down to simple numbers.

I get that counting from one to 10 is tricky for some folk (like CBC editors). It’s easy to get lost and forget that there are ten digits in there. “One, two, three, uh… seven… nine… four… is that it?” But here’s how it works:

1… 2… 3… 4… 5… 6… 7… 8… 9… 10

Feel free to print this sequence out for future reference. Try it using your fingers. See? Ten numbers when you count from one to ten. Pretty amazing, eh? Well, that’s how our calendar works, too.

So if the above arithmetic hasn’t boggled your mind too much already, let’s do some basic counting. We’ll start with a decade. The word itself comes from the ancient Greek through Latin: dekas is in ten in Greek, decas is Latin. A decade can mean a set of ten things, such as books, chapters, or even prayers, but for this article we’re interested in one use: counting years. A decade is ten years. Not nine, not eleven.

Sure, you can pick any arbitrary group of ten years and call them a decade, but that dilutes the significance considerably. 1964-1973 is a decade, technically, but unless it’s associated with a significant historical event or issue, so what? Who celebrated the start of a new decade in 1974?  Same with 2010-2019 – technically correct only as a decade in marketing or in slipshod media reckoning. (I’m sure you are aware that, in the example decade above, it marked the ten years of direct U.S. involvement in the Vietnam War.)

The first decade in the western calendar starts with year 1, just like your fingers do,  and ends with… have you figured it out yet? That’s right! Year 10. Years 1 through 10 are the first decade. Now with a little effort, you can calculate the first century – 100 years. Spoiler alert: that’s years 1 through 100. And the first millennium? Right: years 1 through 1000. See the pattern? You start counting with 1, not 0. Decades, centuries and millennia all start with a year ending in 1. And they close with a year ending in zero. Just like counting from one to 10 on your fingers. You don’t count from 0 to 9, do you? Then why do it with years?

So what is 2020 in those terms? Start with 2001, the first year of this millennium and count 10… 2001 to 2010, then another 10; 2011 to 2020. So 2020 is the LAST year of the current decade, not the start of a new one. Got that? Apparently the CBC doesn’t, but like local media, their credibility is long past its best-before date. I digress.

Calendars are not like the odometer on your car. Odometers start at zero, so when you see 1, you’ve travelled 1 km (or miles if you prefer the archaic imperial system). When the numbers on an odometer roll over to 2,020 it means you’ve travelled a full 2,020 kilometers and number 2,021 is just starting. Calendars, on the other hand start at 1, and the appearance of year 2020 indicates we’ve done 2,019 years and the 2,020th is about to begin, not ending.

You can also count years like you count the pages in a book. You start with one. You don’t begin reading the second set of 10 until you read to the very end of page 10. Or like money – count from one. If I owed you $10 and gave you $9 because I started counting from zero – would you accept it? Think of years as pennies. How many pennies are in $20? Is $19.99 the same amount as $20? Would a bank give you a $20 bill if you gave it $19.99 in pennies? We count house numbers, cookies, bottles of beer – everything else from one. So why are some people trying to make us count years from a non-existent year zero? Zero isn’t a number – it’s a place marker. Doesn’t anyone take math in schools these days? Or maybe they think there’s a ‘decade’ with only nine years lurking in the calendar.

I blame Dennis.

Blame it on Dennis

Dennis the ShortThe western or common calendar is also called the Christian calendar because it supposedly starts with the year that immediately followed Jesus’ birth: year one. But there is no year zero. I’ll explain the reason for that shortly, and why it jumps backwards from year 1  to -1 (or more correctly, to 1 BCE – Before the Common Era – also called BC – Before Christ) with no gap between them. Years after the birth are labelled A.D. for Anno Domini: the year of our lord, but modern, politically correct and non-denominational usage is CE for Common Era. 1 AD or 1 CE is the first year in the western calendar.

We use this calendar because of the efforts of a generally forgotten man: Dennis the Short (sometimes Dennis the Humble), or in his Latin name, Dionysius Exiguus. Dennis was a sixth-century Scythian (now part of Russia) monk and an amateur astronomer. Pretty bright guy. In 532 CE (or 525, 526, or even 534 according to some) he created what would become our modern calendar dating system (although it took a couple of centuries to be widely accepted).

Dennis decided to correct the contemporary dating system which was then using Anno Diocletani – years since the Roman emperor Diocletian. Diocletian was infamous for persecuting Christians and Dennis wanted to glorify Christ, and fix the timetable for Easter, so he worked on a dating system based on the life of Jesus. His then-current year of 248 Anno Diocletiani became the year 532 Anni Domini Nostri Jesu Christi, now known as 532 AD (or CE).

Dennis has little actual historical material to work from. The actual date of Jesus’ birth had long been lost or forgotten by the time he started his quest. And Dennis had to work out that birthday in order to simplify the convoluted 19-year and 84-year Easter cycles the church used. So he turned to the only sources he could find – mostly Roman ones, which were often dated AUC – Ab urbe condita – from the legendary founding of the city of Rome, in 753 BCE, or more often dated according to the year of the consuls in power (2020 will be 2773 AUC, by the way).

Dennis used these often contradictory and confusing dating systems to backtrack to what he believed was the proper year. Good idea, but his sources were not accurate. Nor was his grasp of mathematics. He forget to calculate the impact of the 90 days Julius Caesar inserted into the Roman calendar in 45 BCE to make the Roman holidays align with the seasons. And Dennis didn’t just lose a year in his calculations: he lost a year and a day because year 0 (the actual year when Jesus was born according to his dating) would have been a leap year!*

Dennis was also working in Roman numerals, which aside from being notoriously tricky, did not have a symbol for zero (just try subtracting CCXLVIII from DXXXII or multiplying MCMXVI by LXXXVIII…). Zero as a mathematical entity wouldn’t appear until several centuries later, when the Catholic church adopted the Hindu-Arabic characters for numbers and counting (first in 976 CE, but would not really take off in the West until the 13th century).

The Bible itself doesn’t specify a date for Jesus’ birth. However, Dennis worked from two vague dates in Luke (Luke 3:1 – Jesus was baptized in the 15th year of the reign of Tiberius and Luke 3:23 says Jesus was about 30 years old at the start of his ministry). See this site for some research on dating Jesus’ birth.

Dennis also decided the eighth day after Jesus’ birth (traditionally the date of his circumcision, based on Jewish custom) should be the official New Year – the start of year 1 – as his marker. He chose this day rather than the date of Conception (March 25) or Incarnation (December 25) because it allowed him to place Jesus’ first birthday just before Year 1 and the years to align comfortably with Jesus’ age. Had he made the year of Jesus’ birth as Year 1, then it would have been confusing to have the first birthday in Year 2, etc.

December 25 was the eighth day before the Calends of January in the year 753 A.U.C. and also the winter solstice in the Julian calendar and the same date of a pagan festival called Sol Invictus, celebrated in Rome as the birth of the sun god. Many scholars believe the birth date was changed to Dec. 25 to encourage pagans to convert (and give them a festival on the same day so they wouldn’t have to buy new party hats…). Until 354 CE, Jesus’ birthday was actually celebrated on Jan. 6, but it got moved to the earlier date after Dennis. Today, many modern authorities argue for a spring or fall birth for Jesus, based on historical, literary and astronomical studies, so if they’re right, Dennis’ date for Christmas isn’t even in the right season.**

Despite good intentions, his errors were later perpetuated and compounded by others. Dennis’ dating system was not an immediate success when he proposed it. It took another 200 or so years for it to catch on. Charlemagne may have been the first Christian ruler to use it officially, but it was actually the ‘Venerable Bede,’ an English monk and historian who popularized it in his 731 CE book The Ecclesiastical History of the English People.

Bede recommended the system as a common method for calendar dating and, seeing the omission of dates before Jesus, extended Dennis’ calendar to include earlier years, creating the suffix BC or ‘Before Christ’ for the time before Jesus (which is why we mix Latin AD with English BC). Before Bede, the year before Jesus’ birth was called 1 A.C. (Ante Christum). Bede followed that practice and did not figure a Year 0 into his dating. 

In purely mathematical terms, Year 1 AC/BC/BCE should have been Year 0. If you think of BC/BCE as ‘negative’ numbers, Bede’s calendar goes like this: -3, -2, -1, 1, 2, 3 etc. The missing ‘zero’ is obvious by today’s standards – just as if the calendar was dated 1998, 1999, 2001, 2002 and so on. Mayans, Babylonians and some medieval English kings reckoned years better – even, in the Mayan case, with zero – but not the early Church fathers. 

“When the encyclopedia of human folly comes to be written, a page must be reserved for the minor imbecility of the battle of the centuries — the clamorous dispute as to when a century ends,” wrote Ruth S. Freitag, a senior science specialist in the US Library of Congress’ Science and Technology Division Noting that there was no “year 0” in history, she said, “In fact, there has never been a system of recording reigns, dynasties, or eras that did not designate its first year as the year 1.”

Calendrical idiocy of this sort that celebrates 2020 as the start, not the final year, of a decade, seems too widespread to halt. We couldn’t stop the arithmetically-challenged idiots from celebrating the “new millennium” a year too early, when Jan. 1, 2000 arrived, so it’s unlikely we can educate people about how to count to ten for decades today. It’s an all-too-obvious indication of the greater dumbing-down of our society and the waning credibility of media outlets eager to jump on whatever bandwagon floats their way without giving the ride any critical thought.***

* The calendar got even more confused a few centuries after Dennis. Easter was again drifting out of season, getting later each year. Julius Caesar had inserted leap years into the calendar every four years to help make up for the uneven number of days in a year (365.24219) and to compensate for the drift, but it didn’t account for that remaining fraction. When Pope Gregory revised the Julian calendar in 1582, a certain number of days were omitted from his new calendar to correct for this accumulated drift. Since the Julian leap year makes for an average year of 365.2425 days, Gregory also decreed that years that end with “00” should only be a leap year if evenly divided by 400 to correct the rounding problem (that’s why 2000 was a leap year).

Julian’s reformations came in an age when Protestants were merrily discarding everything Catholic regardless of intrinsic value. They objected to losing the days from October 5 to 14 inclusive simply because the Pope decreed it. Protestant England (and her colonies) persisted in using the “Old Style” calendars. This resulted in two separate styles of dating among Europeans for a long time. We lost the 11 days from the calendar only in 1752 when the switch was made in English-speaking countries from the Julian to the Gregorian calendar. So Dec. 31, 1999 is really Dec. 20 by the old reckoning.

When the Gregorian calendar was adopted in Britain in 1752, September 2nd was followed by September 14th. Historical dating through this period is very difficult at times: March 8, 1735, Old Style is really March 19, 1735 in the New Style. One of the last to change, Russia remained with the old calendars until the Revolution in 1917.

And finally – the first of the year also shifted around a lot. Benedictines, for example, celebrated the year as beginning on December 25th. Before 1582, most calendars did not show the year starting January 1, even though the calculation of the moveable religious feasts acted as if it did. In England, the year “began” either on December 25th, or, more frequently on March 25th (Lady Day), until 1752 when the “New style” was adopted with January 1 as the start, the date we’ve stuck with ever since.

** Jesus, based on the New Testament chronicles, was born in Herod’s reign. According to Flavius Joseph, a reasonably good source of contemporary history, Herod died shortly after a spring eclipse of the moon (but before Passover). There are three possible eclipses around that time (5 BC, 4 BC and 1 BCE, but the consensus among Biblical historians is the March 13 eclipse, 4 BCE (Julian year 4710 or AUC 749). Since Herod declared he would kill all the children under the age of two, Jesus must have been under 2 years old in 4 BC – thus already between four and six years old on the date Dennis set for his first birthday.

*** To their credit, the Farmers’ Almanac weighed in on the correct side of this argument, noting,

“As you think about New Year’s resolutions, here’s one we should all make together: resolve to insist that decades begin with the year ending in the numeral 1 and finish with a 0. For a decade to begin, we must start with the year ending with 1 (2021) and finish with 10, or so far as chronology is concerned, a year ending in 0 (2030)… So let’s face it, from a mathematical point of view, a new decade is still a year away, in the year 2021.”

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    “The Gregorian calendar’s shortcomings are magnified by the fact that multiple improvements have been formulated, proposed to the public and then largely ignored over the years — most recently in 2012, with the unveiling of a highly rational streamlined calendar that addresses many of the Gregorian calendar’s problems. According to the calendar’s creators, it would generate more than $100 billion each year worldwide and “break the grip of the world-wide consensus that embraces a second-rate calendar imposed by a Pope over 400 years ago.” This attempt, like many of the others, has received some media attention but has thus far failed to gain any meaningful traction with policymakers or the wider public.”

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