Year Zero?

[Trebuchet]

In this week's commentary, Randi discusses Bishop Usher's calculation of the age of the Earth and suggests he got it wrong by omitting the year zero. I'm open to correction but I think in this case Usher got it right and Randi has it wrong -- there wasn't any year zero, any more than there's a zeroeth of January on the calendar or zero o'clock on the clock.

The year one AD or CE is simply the first year after the arbitrary zero point in time, just as one BC or BCE is the first year prior, counting backward. No time elapsed between them.

Or am I missing something?

[Jeff Corey]

What was the year between 1 B. C. and 1 A. D. (old terminology)? Did it just jump from -1 to +1 with nothing in between?
Then again, I have never seen anything dated 0 A. D.
"On Septimus X, 0 A.D., Biggus Dickus ordered a purge of all those silly people of the Jewish persuasion."
(Bad Python Parody of a Parody Department)

[xouper]

Trebuchet: In this week's commentary, Randi discusses Bishop Usher's calculation of the age of the Earth and suggests he got it wrong by omitting the year zero. I'm open to correction but I think in this case Usher got it right and Randi has it wrong -- there wasn't any year zero, any more than there's a zeroeth of January on the calendar or zero o'clock on the clock.

The year one AD or CE is simply the first year after the arbitrary zero point in time, just as one BC or BCE is the first year prior, counting backward. No time elapsed between them.

Or am I missing something?All the sources I know of say that the year before 1 CE is called 1 BCE.

For example,
http://www.usno.navy.mil/millrel.html
http://en.wikipedia.org/wiki/Proleptic+Gregorian+Calendar
http://astro.nmsu.edu/~lhuber/leaphist.html

In the proleptic Gregorian calendar, if you use negative year numbers, then there is a year zero, but not if you use the BCE notation.

<table border=1 cellpadding=4><tr><td>3 BCE</td><td>-2</td></tr><tr><td>2 BCE</td><td>-1</td></tr><tr><td>1 BCE</td><td>0</td></tr><tr><td>1 CE</td><td>1</td></tr><tr><td>2 CE</td><td>2</td></tr><tr><td>3 CE</td><td>3</td></tr></table>

[rem]

Thanks for bringing this up. I believe you are correct - there was no "zero" year. That is why the new Millenium started in 2001... not 2000.

rem

[BillyJoe]

rem,

Originally posted by rem
....there was no "zero" year. That is why the new Millenium started in 2001... not 2000.You are not really wrong but.....

Well, it's more to do with what we mean when we say it is the year 2000. After midnight on 31st Dec 1999, the year 1999 becomes the year 2000 and, of course, we all understand this to mean that we are entering the year 2000. Then at midnight on 31st Dec 2000, when the year 2000 becomes the year 2001, we have of course just completed the 2000^th year - meaning that 2000 years have now passed and hence that a new millenium is beginning.

So, yes, the new millenium started in 2001.

However, if you want to rely on the absence of the year zero to make your argument, then all sorts of other factors have to be considered as well such as the several occasions that the calender has been adjusted.

regards,
BillyJoe

[rem]

BillyJoe,

I understand what you are saying, but basically what you said is that the reason the millenium ends with a one instead of a zero is a consequence of starting with year 1 instead of 0.

The way we count years on the calendar is different than how we count years in our birthday, so consequently the years seem to be a year off when you are counting elapsed time.

If you were born in the year 1, you would be 19 years old in year 20... you would be 99 years old on year 100... and you would be 1999 years old on year 2000. If the calendar had also started with a year 0 then the birthday and the calendar would have matched.

I was not trying to use the year 2001 as proof of a year zero - that's pretty much common knowledge you can get off the net or just by studying bible history. I was merly pointing out a modern consequence of not having a year zero which might help someone who didn't already know see that things seem to be off by a year.

http://www.timeanddate.com/counters/mil2000.html

http://www.tondering.dk/claus/cal/node3.html#SECTION003132000000000000000

I know you said I wasn't really wrong... I just have a hangover so I'm extra irritable right now. :)

rem

[BillyJoe]

rem,

Originally posted by rem
I understand what you are saying, but basically what you said is that the reason the millenium ends with a one instead of a zero is a consequence of starting with year 1 instead of 0.Yes, that's why I made a point of saying you are not really wrong :)

The other point I was trying to make is that, at midnight on 31st Dec 1999, it becomes the year 2000 and, of course, what this means for us is that we are commencing the 2000th year. I mean we feel[/]i]that to be the case. We don't sit down and try to figure out what it means. We don't say to ourselves "Now let me see....there was no year 0, so it all started with the year 1.....so therefore that would have been the beginning of year 1.....so now that it is the year 2000, we must be at the beginning of year 2000."

But anyway you understood that. :cool:

[i]Originally posted by rem
The way we count years on the calendar is different than how we count years in our birthday, so consequently the years seem to be a year off when you are counting elapsed time.Except that when you celebrate your 20th birthday where you live right now, if you lived in any of a number of European countries, you would be celebrating your 21st year instead. Also, I don't think we make a mental comparison between birthdays and calender year. Do you?

Originally posted by rem
If you were born in the year 1, you would be 19 years old in year 20... you would be 99 years old on year 100... and you would be 1999 years old on year 2000. If the calendar had also started with a year 0 then the birthday and the calendar would have matched. Yes, okay, but the point you missed is that when we say it's your 20th birthday, what we actually mean is that it is the twentieth anniversary of your actual birth. Do you agree? :)

Originally posted by rem
I was not trying to use the year 2001 as proof of a year zero - that's pretty much common knowledge you can get off the net or just by studying bible history. I was merly pointing out a modern consequence of not having a year zero which might help someone who didn't already know see that things seem to be off by a year.Okay, well lets summarize this so it makes sense and looks consistent.....

When it is the year 2000, what we mean is that we are "in the 2000th year of the common era"
When we are 20, what we mean is that we are "in the 20th anniversary year of our birth"

What do you think? :)

Originally posted by rem
I know you said I wasn't really wrong... I just have a hangover so I'm extra irritable right now. :) I am glad you are able to smile through your hangover.
Yes, we have slightly different slants on the same idea. :)

regards,
BillyJoe

[Rolfe]

It's when all the numbers on the odometer went round together. I'm simple that way.

Rolfe.

[Hutch]

If I remember right, Stephen Gould addressed this issue in one of his books (I'll look it up tonight)

Apparently when the Chrisitan Church began to divide the eras, they forgot to put in a year zero--if I remember correctly, this is something else we can hang on our old friend Bishop Ussher.

I'll cite chapter and verse later tonight unless someone beats me to it. It is, like most Gould essays, very good.

[Hutch]

Found it, book is Dinosaur in a Haystack by Stephen J. Gould. Second essay in is "Dousing Diminutive Deniis's Debate or DDDD=2000."

Explains how we ended up without a year zero. Was the Monk's fault. :D

You could also probably find it in Natural History magazine during 1999-2000, but don't have those issues at home.

[BillyJoe]

If you were starting up a calendar would you begin with the year 0 or 1

I vote 1

[Walter Wayne]

The language used determines whether one begins with 0 or 1. When someone is born we say they are in their first year, but we don't say they are 1 for 12 months when they are starting their second year.

A.D. = year of our lord.
We start with the "first year of our lord".

The change in language is what screws it up. We tend to say it is year 2004 AD/CE, but what we really mean is it is the 2004th year of our lord, or the 2004th year of the common era.

[xouper]

BillyJoe: If you were starting up a calendar would you begin with the year 0 or 1Interestingly, most of the Mayan calendars start with zero.

[TheBoyPaj]

I'd go for 1 too.

I think it represents the "first year" (similar to "the first of January", the first house on the street etc) rather than a measure of time that has passed.

But it is confusing, which is why we had that whole debate about when the Millennium ended.

[BillyJoe]

Originally posted by xouper
Interestingly, most of the Mayan calendars start with zero. I think they were just boasting though.

[Andonyx]

Originally posted by BillyJoe
If you were starting up a calendar would you begin with the year 0 or 1

I vote 1

I see and for the first year of a baby's life, are you one years old, or zero years old?

You're zero.

Because the notation of one, should theoretically mean one complete unit.

You have not reached one until an entire year has passed. Then you are one years old. It is year one, etc.

If you line up sheep to be counted, the first sheep is one sheep, but only if it is a complete sheep. A pile of wool, and some hooves doesn't not make 1 sheep.

When you are 29 years old you are in the process of completing your 30th year...etc.

All things being equal, it would make far more sense to me to start with a year zero.

[BillyJoe]

Andonyx,

Originally posted by Andonyx
I see and for the first year of a baby's life, are you one years old, or zero years old? Well I am neither one years old nor zero years old ( ;) ) but the baby's age IN THE FIRST YEAR OF ITS LIFE is usually measured in weeks and then months.
However, if pushed, I would say "the baby is in the first year of its life" rather than "the baby is zero years old".

Originally posted by Andonyx
You're zero. No, I'm a little bit older than that. ;)

Originally posted by Andonyx
You have not reached one until an entire year has passed. Then you are one years old. Yes, actually I agree. :)

Originally posted by Andonyx
If you line up sheep to be counted, the first sheep is one sheep, but only if it is a complete sheep. A pile of wool, and some hooves doesn't not make 1 sheep.:D (Well, this did make me laugh but it wasn't really funny enough to laugh out loud. But still "a good one" Andonyx)

Originally posted by Andonyx
When you are 29 years old you are in the process of completing your 30th year...etc. :) (I agree)

Originally posted by Andonyx
All things being equal, it would make far more sense to me to start with a year zero. Perhaps it's more to do with preferences than sense - you prefer to move smoothly along and I prefer to jump.

regards,
BillyJoe

[xouper]

When counting things (such as sheep or days), I prefer to start counting with 1. When measuring things (such as distance or elapsed time), I prefer to start measuring at zero. So I guess it depends on whether a calendar is used for measuring elapsed time or for counting things.

That's my 1.999... cents, anyway.

[Trebuchet]

By all means start your calendar, or your baby's life, with zero but remember it's a moment -- an instant in time -- not a whole year! The year "1" is the entire first year. We don't say the baby is a year old until it's over but it's still his first year. I'm in my 56th year but I'm only 55 and some months at this point. Got it?

[BillyJoe]

xouper,

Originally posted by xouper
When counting things (such as sheep or days), I prefer to start counting with 1. What about if you only have a couple of hooves and a bit of wool? :D:D

Originally posted by xouper
When measuring things (such as distance or elapsed time), I prefer to start measuring at zero. So I guess it depends on whether a calendar is used for measuring elapsed time or for counting things.Well, it counts things obviously - days, weeks, months, years, decades, centuries and millenia (well, maybe not those last few) - but I certainly don't hear it ticking.

Originally posted by xouper
That's my 1.999... cents, anyway. No, no, your contribution is worth at least 2 cents. :cool:

BillyJoe

[psy kick]

So...in the year 0, they just said it was Month 1, Month 2, etc?

I thought Jesus was born April 31st?

[ehbowen]

Consider this: If you are going to have a "year zero," you will need to have TWO year zeros: a year 0 B.C. and a year 0 A.D., for the same reason that a number line contains the points 0.5 and -0.5.

Keep this in mind: Zero is a point on a number line, while a year is a region of time. There is a zero point in our Gregorian calendar: It is midnight, December 31, 1 B.C./January 1, 1 A.D. Events which occur during the twelve month period prior to that zero point are properly regarded as having occured in the first year B.C., and events in the twelve month period after that zero point are recorded as occuring in the first year A.D.

[Captain Trips]

Having read all your above posts, I think I can sum it up easily enough:
Two minutes after 11:59pm, Dec 31, 1 BC(E) it will be 12:01am, Jan 1, 1 AD (CE).
Yes, the "zero" is just a point halfway between the above two minutes, or the exact stroke of midnight. By mathematical definition, zero isn't a number, it's a concept without dimension. Years have dimension (1 year long on a time axis.) Therefore, the "year zero" is a meaningless idea, and to contemplate its existance is an exercise in nothing.

In other words, Randi may have goofed on this one point. (Pardon the pun.)

[BillyJoe]

Originally posted by ehbowen
Keep this in mind: Zero is a point on a number line, while a year is a region of time. There is a zero point in our Gregorian calendar: It is midnight, December 31, 1 B.C./January 1, 1 A.D. Events which occur during the twelve month period prior to that zero point are properly regarded as having occured in the first year B.C., and events in the twelve month period after that zero point are recorded as occuring in the first year A.D. :)

[xouper]

Captain Trips: Having read all your above posts, I think I can sum it up easily enough: Two minutes after 11:59pm, Dec 31, 1 BC(E) it will be 12:01am, Jan 1, 1 AD (CE).So far so good.

Yes, the "zero" is just a point halfway between the above two minutes, or the exact stroke of midnight.By that logic, what is the point halfway between 11:59pm Dec 31, 2003 and 12:01am Jan 1, 2004?

By mathematical definition, zero isn't a numberZero is indeed a number, and is part of the integers, rationals, and reals, for example. Do you have a cite that says otherwise?

it's a concept without dimension.No different than 1, or 2, or any other number that doesn't have a dimension, which would include all real numbers.

Therefore, the "year zero" is a meaningless idea, and to contemplate its existance is an exercise in nothing.Then please explain why the years are numbered as follows in the proleptic Gregorian Calendar:

... -3, -2, -1, 0, 1, 2, 3 ...

where year zero corresponds to 1 BC, as I posted previously, which you claim to have read.

Also please explain why the use of zero in the Mayan Calendar is meaningless?

[TheBoyPaj]

Originally posted by Andonyx
You have not reached one until an entire year has passed. Then you are one years old. It is year one, etc.

If you line up sheep to be counted, the first sheep is one sheep, but only if it is a complete sheep. A pile of wool, and some hooves doesn't not make 1 sheep.

When you are 29 years old you are in the process of completing your 30th year...etc.

All things being equal, it would make far more sense to me to start with a year zero.

But don't all the months start with day 1? Why is January itself given the number 1 when a numerical date is written?

By your standard, January the first would be 0/0

If our notation of days and months doesn't use zeros, neither should the years.

[ehbowen]

Originally posted by xouper
By that logic, what is the point halfway between 11:59pm Dec 31, 2003 and 12:01am Jan 1, 2004?

Well, in the military (US Navy at least), there is no such thing as "2400 hours." At the stroke of midnight, the day changes from 23:59:59 the original day to 00:00:00 the next day. So the answer to your question is that that point is 12:00:00 am January 1, 2004.

[xouper]

ehbowen: At the stroke of midnight, the day changes from 23:59:59 the original day to 00:00:00 the next day. So the answer to your question is that that point is 12:00:00 am January 1, 2004.Agreed. However, that answer does not seem consistent with what you posted previously, that 12:00:00 am January 1, 1AD is called the zero point. Please clarify.



Caution - thread drift ahead. :)

Regarding your comment about 2400 hours, I haven't been in the U.S. Navy, so I will have to take your word that they don't use it. However, I would like to note that 2400 is a valid designation according to the International Standard ISO 8601, which specifies numeric representations of date and time.

http://www.cl.cam.ac.uk/~mgk25/iso-time.html

As every day both starts and ends with midnight, the two notations 00:00 and 24:00 are available to distinguish the two midnights that can be associated with one date. This means that the following two notations refer to exactly the same point in time:

1995-02-04 24:00 = 1995-02-05 00:00

In case an unambiguous representation of time is required, 00:00 is usually the preferred notation for midnight and not 24:00. Digital clocks display 00:00 and not 24:00.

[BillyJoe]

Originally posted by TheBoyPaj
But don't all the months start with day 1? Why is January itself given the number 1 when a numerical date is written?

By your standard, January the first would be 0/0

If our notation of days and months doesn't use zeros, neither should the years. Yes, it depends on whether you want to crawl or jump.....

Crawling: 0.....start of first year.....middle of first year....end of first year....start of second year....

Jumping: year 1 → year 2 → year 3

regards,
BillyJoe
(But I'm not sure I'm making any sense :D )

[Blondin]

Say I want to walk to the post office which is 6 blocks away and I leave my house and step out of my gate and turn towards the post office. At this point I have travelled 0 blocks but I am at block 1 of the journey. After walking 2 blocks I have travelled 2 blocks but I am at block 3.

distance travelled is analogous to time elapsed
current position is analogous to current time/date

I have lived about 47.2 years so I am in my 48th year.

I've decided that instead of celebrating annually I am going to celebrate my birthday everytime I reach half the time between now and my 50th year. Since I can keep dividing the time in half forever (an infinite number of times) I will experience birthdays more and more frequently and yet I will never be older than 50!

Chocolate icing please... :D

[BillyJoe]

Blondin,

That last second is going to be divided in half an infinite number of times and at each point you are going to be celebrating your birthday.
But with one tick of the clock it will all be over.

:D

BillyJoe

[ceo_esq]

In my view, the most intuitive explanation for why calendar years and people's ages are calculated differently is they are used to signify a different kind of measurement.

To indicate that an event occurred in a given year is to localize it in time by indicating the twelve-month span during which it took place, relative to a starting point. For example, Columbus' first voyage to the New World occurred during the course of the 1492nd twelve-month period following the starting point.

Your age, on the other hand, is generally used to indicate milestones passed (you celebrate your 30th birthday only after completion of your 30th year). One logical reason would for this would be that the completion of a given milestone is usually the relevant criterion for age-related determinations in daily life (and there are many more such determinations to be made today than there used to be). Have you passed milestone #21? Then you can buy yourself a beer in the United States. Have you passed milestone #65? Then you can collect your full social security retirement benefit there.

Interestingly, particularly in older writing, it was not uncommon to see biographical events related according to the calendar-type calculation. For example, you might see either the formulation "So-and-so died at the age of 69" or the formulation "So-and-so died in his 70th year", presumably without any confusion on the part of the intended audience.

By the way, someone mentioned that in certain European countries, ages are calculated starting with 1 rather than zero. As long as I've lived in Europe, I've never heard of such a thing. Does anyone have any further information on this?

[Skeptic]

People, there wasn't a year 0 for the same reason there wasn't a zeroeth century or a zeroeth milennium, or for that matter, a 0th day in a month or the 0th day of the week: years in the caleander are ordinal (first, second, third in line) not cardinal (one, two, three apples). The year 1 was the FIRST year CE, the year 2 was the SECOND year CE, etc. There is no such thing as being "zeroeth" in line, while there IS such a thing as having zero apples.

The confusion arises because for we usually do not use the ordinal name for years, while we DO use them for all other units of time in the calendar. We say the "first week of the month", or the "second thursday in February" (not "two thursday"), or "May fifteenth" (not May "fifteen"), or the "twentieth century" (not "twenty" century).

The reason for this, however, is not that specific years--as opposed to hours, days, weeks, month, centuries, milleniums, etc.--are somehow cardinal while everything else is ordinal. It's just that it is inconvenient to add "-th" to every historical date. We SHOULD say "the 1976th year CE" and not "the year 1976 CE", but it's just not convenient.

[Blondin]

Originally posted by BillyJoe
Blondin,

That last second is going to be divided in half an infinite number of times and at each point you are going to be celebrating your birthday.
But with one tick of the clock it will all be over.

:D

BillyJoe

Just think of all the chocolate cake. That last second will never end because I will perform a "Mr Creosote" before the last tick.

[BillyJoe]

Originally posted by Blondin
That last second will never end because I will perform a "Mr Creosote" before the last tick. It's probably a good joke but, unfortunately, it's lost on me. :cool:

[BillyJoe]

ceo_esq

Originally posted by ceo_esq
Your age.....is generally used to indicate milestones passed (you celebrate your 30th birthday only after completion of your 30th year). Well, actually, what do you mean when you say it's your "30th birthday"? Do you mean literally that you are being born for the 30th time??? No. What you actually mean is that you are celebrating the 30th anniversary of your birth. 12 months after you are born you celebrate the first anniversary of your birth which we conveniently shorten to your first birthday
This is the real reason birthdays and calenda dates are different.


Originally posted by ceo_esq
By the way, someone mentioned that in certain European countries, ages are calculated starting with 1 rather than zero. As long as I've lived in Europe, I've never heard of such a thing. Does anyone have any further information on this? Well, what I said (or meant to say) is that in some places in Europe they do not think of themselves as being (for example) 69 years of age but instead think of themselves as being in their 70th year. It's something I heard from a relative visiting from Holland. (At the time I responded "ah, but we're optimists over here :) ). It is possible that the observation by my relative was not accurate?

BillyJoe

[xouper]

Skeptic: People, there wasn't a year 0 for the same reason there wasn't a zeroeth century or a zeroeth milennium, or for that matter, a 0th day in a month or the 0th day of the week ...Don't tell the Mayans that. :)

[Blondin]

Originally posted by BillyJoe
It's probably a good joke but, unfortunately, it's lost on me. :cool:
Mr Creosote refers to one of the skits in Monty Python's The Meaning of Life.

I meant I would probably explode before I could consume an infinite amount of chocolate cake (do ya think?).

[Quixote]

quote:
--------------------------------------------------------------------------------
Skeptic: People, there wasn't a year 0 for the same reason there wasn't a zeroeth century or a zeroeth milennium, or for that matter, a 0th day in a month or the 0th day of the week ...
--------------------------------------------------------------------------------

Don't tell the Mayans that.

I believe he was speaking from a eurocentric viewpoint. I regret that the calendar never came up in any of my conversations with Mayans.

[LW]

Originally posted by Hutch

Apparently when the Chrisitan Church began to divide the eras, they forgot to put in a year zero--if I remember correctly, this is something else we can hang on our old friend Bishop Ussher.


Well, blaming Ussher for that is a little like blaming G. Bush for the Black Death of the 14th century.

Ussher lived in the 17th century (1581-1656). The practice of counting years from Jesus's supposed birthdate begun with the monk Dionysius Exiguus who compiled a chronology in 527 AD.

If you look closer at the date, you might notice a quite concrete reason for the lack of year 0: the calendar was instituted roughly 700 years before the number '0' was introduced in Western mathematics.

Also, the fact that Dionysius didn't probably get the birth year correct is not so surprising since the Gospels of Matthew and Luke have ~10 year discrepancy between them. [By the time Quirinus came to be the Procurator of Judea Herod the Great had lied in his grave for years.]

[Captain Trips]

Originally posted by Skeptic


The confusion arises because for we usually do not use the ordinal name for years, while we DO use them for all other units of time in the calendar. We say the "first week of the month", or the "second thursday in February" (not "two thursday"), or "May fifteenth" (not May "fifteen"), or the "twentieth century" (not "twenty" century).

I think that's hitting the nail on the head. We use ordinal numbers for years, and who ever heard of "the zeroth item?" We always start with "the first thing". So, we started the count with "the first year, being year 1."

Are we there yet? Come on, isn't this thread just driving a trivial point into the ground?

[BillyJoe]

Originally posted by Captain Trips
Come on, isn't this thread just driving a trivial point into the ground? Yeah and who's just pushed the thread onto the second page.

[Loki]

LW,

There I was, reading along and thinking "this might be a good moment to mention the rather late arrive of zero into western maths", and I come across this :

If you look closer at the date, you might notice a quite concrete reason for the lack of year 0: the calendar was instituted roughly 700 years before the number '0' was introduced in Western mathematics.
Thanks very much - now I have nothing to contribute! (Damn scandinavians....)

[Maccara]

LW,

Should we introduce into this discussion how we "crazy finns" generally note f.e. 20th century and how it differentiates for the notation of the 60's? ;) (even our "professional" translators seem to get it frequently wrong, which is actually quite amusing at times)

[davefoc]

LW said:Also, the fact that Dionysius didn't probably get the birth year correct is not so surprising since the Gospels of Matthew and Luke have ~10 year discrepancy between them.

LW's statement inspired me to do a little research. I thought he was wrong because there were two king Herods, King Herod the great who died in 4 B.C. and his son, Herod Antipas who ruled after him.

Alas it seems that LW was right and this expands on that a litlle:
Matthew claims that the birth of Jesus occurred during the reign of Herod the Great of Judea, a puppet king of the Romans, whom we know died in 4 B.C. Luke also tells us that Jesus’ birth happened during Herod's reign. Luke even adds what appears to be detailed and historical evidence of the period. He writes that Jesus was born during a census or registration of the populace ordered by emperor Augustus at the time that Quirinius (Cyrenius) was Roman governor of Syria (Luke 2:1-3). In reality, this has to be a fabrication because Quirinius was not governor of Syria and Judea during Herod's kingship. Direct Roman rule over the province of Judea, where Bethlehem was located, was not established until 6 A.D. In other words, ten years separated the rule of Quirinius from Herod.

Source: http://www.religioustolerance.org/xmas_lib.htm

This site might be worth a look. I found it to be quite interesting. One of the things that I wasn't aware of was how stories from the old testament served as a basis for some of the new testament stories.