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As December 31, 1999, approaches, disputes over when the new millennium "officially" begins become sharper. Most people are ready to party, celebrating the start of a new millennium on January 1, 2000. But a vocal group of critics claims that no, the new millennium doesn't really begin until January 1, 2001. Is it possible to decide this question once and for all?
No. That's because there are three answers to the question:
Here is the reasoning behind the traditional answer:
The traditional system of numbering years has no year 0. The first year of the first millennium was 1 AD. The year before that is numbered 1 BC. Since the first millennium began with the year 1, its last year was the year 1000. Similarly, the last year of the second millennium is the year 2000, and the first year of the third millennium is 2001.
As long as we keep the traditional system of numbering years, there's no arguing with this reasoning.
Now here is the reasoning behind the reformed answer:
Not having a year 0 is a big mistake. It means that our familiar system of arithmetic with signed numbers doesn't work for year numbers. Consider a girl who is 12 years old in the year 4 AD. In what year was she born? We know 4 - 12 = -8, but 8 BC is the wrong answer. Clearly she was 9 years old in 1 AD, and 8 years old in 1 BC. So she was 7 in 2 BC, etc., etc. (we seem to be counting on our fingers here) and she turns out to have been born in 9 BC. The rules are:
- The number of years elapsing between p BC and q AD is p + q - 1, and
- The year n years before q AD is q - n AD if n < q, but it is q - n + 1 BC if n is equal to or greater than q.
This seems pretty dumb, and it is a big inconvenience for historians, astronomers, archaeologists, and other people whose work causes them to consider dates both before and after the start of the numbering system. Increasingly, these professionals are saying, let's do something else with the designation of years "before Christ."
In many countries, of course, people are somewhat uncomfortable with the designations AD and BC, because they are not of the Christian religion. AD stands for the Latin phrase Anno Domini, "the year of the Lord," meaning Jesus Christ. A custom has arisen in non-Christian countries of replacing AD with the designation CE, an abbreviation for "common era." Thus 1999 AD is also designated 1999 CE.
For purposes of calculation, the CE numbering system is regarded as having a year 0. Thus 1 BC is also 0 CE, and 2 BC becomes -1 CE. If a boy is 12 years old in 4 CE, he was born in -8 CE, as one would expect. We just have to remember, but only if we want to go back to the old system, that a "negative" year -n CE is the same as n + 1 BC.
In the CE numbering system, it makes sense to think of 0 CE as the "first" or initial year. If we do that, then the first millennium is from 0 to 999 and the second from 1000 to 1999. This makes 2000 the first year of the third millennium.
Finally, the religious answer:
The traditional numbering system was devised by the Catholic scholar Dionysius Exiguus ("Dennis the Small"), who lived about 500 years after Jesus. He never claimed to have accurately fixed the date of Jesus's birth. He just wanted to replace the year numbering systems of the defunct Roman Empire with a new system that would cover the history of the Christian church. In other words, the year numbering system is arbitrary, not scriptural.The Christian Gospel does describe the date of Jesus's birth in a precise way, but historians are not able to put exact dates on all the scriptural references. It is quite clear, though, that Jesus was born after Augustus became Roman emperor, which was in -26 CE (27 BC), and at least a few years before the death of King Herod of Judea. Herod died in -3 CE (4 BC). This means Jesus was born no later than -5 or -6 CE so the traditional numbering system is off by at least that much. The third millennium of Christianity actually began sometime in the early 90's.
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Posted July 9, 1999.
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