Steven Dutch, Natural and Applied Sciences, Universityof Wisconsin - Green Bay
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In a way, it's fitting that the 20th Century ended with a debate about whether the newcentury and millennium began on January 1, 2000 or January 1, 2001. The century began withthe Titanic, a boat that looked fine but was not built as well as many otherships of the time (double-hull construction was becoming widely used, but not for the Titanic).It ends with most organizations wallowing in a Dilbertesque morass of administrivia,drafting goals, objectives, mission statements and assessments. In between, we had amusical composition that consisted of 4 minutes and 33 seconds of silence, a crucifix in ajar of pee-pee hailed as cutting-edge art, the Dress for Success movement, the junk bondscandal of the '80's, and Milli Vanilli. One of the leading philosophers of the 20thcentury is best remembered for inventing the paradox of "the set of all sets that arenot members of themselves." In short, the 20th century was an age of scientific andtechnical brilliance and cultural vacuity. It's fitting that a century that consistentlyglorified form over substance ends with a group of purists arguing that the new centuryand millennium begin in 2001.
I have no use for purists. Every hobby I know of has been ruined by them. They can'tsimply enjoy coins or stamps or model trains, they have to look down their noses at otherhobbyists whose collections aren't as fine as theirs. Purists might serve a useful purposeif they also achieved excellence in something meaningful, but they almost never do. Almostalways, they pick some piece of trivia to obsess over and feel superior to everyone elseabout their ultra-fastidiousness. And for some, the mere fact that most people willcelebrate in 2000 is reason enough to insist that the real millennium begins in2001.
When you count on your fingers, you begin with one. It does not surprise me in theleast that millennial purists count on their fingers. Timekeeping, on the otherhand, starts with zero. You don't begin timing a race at one second, but at zero.
Computers also begin counting with zero. Zero is a perfectly good number, and computersneed it, so why let it go to waste? The 256 characters coded by the 8-bit ASCII codingsystem are not numbered 1-256, but 0-255. In binary notation, 255 is 11111111, but 256 is100000000, requiring one extra digit. Using an extra digit to code one lousy number ispretty wasteful, whereas the range 0-255 can be coded using only eight binary digits, andevery number is represented.
Because 2+2 = 5 creates obvious practical problems and defining the millennium asbeginning in 2000 doesn't. If you disagree, name one.
It begins whenever we decide it does. Calendars are made to serve people, not the otherway around. And unlike the year (time it takes to go around the Sun), month (approximatetime for the moon to circle the earth) and even week (time between major phases of themoon), centuries and millennia have no physical significance beyond the fact that we haveten fingers.
Our present dating system is a Christian year numbering system grafted onto a Romancalendar. When he took power, Julius Caesar reformed the Roman calendar, which was badlyout of sync with the seasons. He brought the calendar back in line, creating a so-called"year of confusion" - it had over 400 days - to make the adjustment. He alsoinstituted Leap Year to keep the calendar in tune with the seasons better, and set January1 as the date of New Years'. January 1 is a completely arbitrary day with no astronomicalsignificance at all - it is neither the solstice nor the date when earth is closest to thesun. The year had begun in March - September was originally the seventh month (Latin septem= 7). He renamed the month of Quintilis after himself and took a day off February to make"his" month longer. His successor Augustus (see where this is going?) did thesame to the month Sextilis. You can thank the Caesars for "thirty days hasSeptember..."
In the Fourth Century, the Christian monk Dionysius Exiguus thought it would be a goodidea to redefine the year numbering system to begin with the birth of Christ instead ofthe legendary founding of Rome. He calculated that Christ was born in 753 A.U.C. (AbUrbe Condita - "since the founding of the city"). In selling his system,which we use today, he created several problems:
The reformed (Julian) calendar was good but still not perfect and by the 1500's theaccumulated errors added up to 10 days. This was important to the Church because the dateof Easter is determined astronomically. Christ was crucified just before Passover, whichis the first full moon after the spring equinox. Hence Easter is the first Sunday afterthat. To predict the date of Easter it is necessary to be able to predict the motions ofboth the Sun and the Moon.
Pope Gregory XIII convened a panel of astronomers, who recommended dropping 10 daysfrom October 1582 to bring the calendar back in line with the seasons (if you think peoplewere upset over paying a full month's rent for a 21-day month, you're right. There wereriots.) They also added a slight refinement: century years would not be leap years unlessthey were divisible by 400. Thus 1700, 1800 and 1900 were not leap years but 2000was- the rarest scheduled event in history.
Despite the problems between the Church and Galileo, the Church was solidly ahead ofthe curve on this point, and Protestant countries grudgingly fell into line over theyears. In the interim travelers had the bizarre situation that a short trip fromProtestant Augsburg to Catholic Regensburg in Germany required them to adjust theircalendars by 10 days. England gave in in 1752. George Washington was born on February 11in the old calendar, not February 22 (and definitely not on the third Monday in February!)Greece and Russia didn't adopt the revised, or Gregorian calendar until the 20thcentury.
Astronomers have needed to do calculations extending before the birth of Christ foryears, and so they were the first to feel the effects of not having a year zero. So theycreated one. Astronomical year zero is 1 B.C. Julius Caesar was assassinated in 44 B.C.but -43 in astronomical years.
Since Christ was actually born in 4-6 B.C., if you really must be anal, thenext millennium actually began somewhere between 1994 and 1996.
If we stick with the present numbering system, we have a choice. We can perpetuate theinconsistency of having years in the same century begin with two different numbers, or wecan redefine the First Century so that century numbering runs logically and consistently:1900-1999, 2000-2099, and so on.
Since the origin of the calendar is inaccurate to begin with, and our "year"is not strictly astronomically accurate but varies between 365 and 366 days, not tomention the more drastic adjustments of the Julian and Gregorian reforms, and astronomersoccasionally insert extra seconds in the calendar to keep the astronomical and civiltimekeeping systems in agreement, complaining about a First Century with only 99 yearsseems pretty nit-picky.
But a century means 100 years. It comes from Latin centum,for 100. So what? The dictionary is full of words that have different meanings than theirLatin roots. But, if you really must have centuries of the same length, definethe First Century to begin in astronomical year zero (which is A.D. anyhow). If you didn'tknow there was a year zero in astronomy, let me respectfully suggest you're notinformed enough to tell others when to begin their centuries. That will have no impact atall on dates A.D. It will push B.C. centuries back by one year. Give me a list ofpractical effects such a change will have.
I guarantee that purists will not accept this solution. It's technically correct, andhas no negative effects of any consequence, but it's no fun. How can you feel superior toeveryone else if you adopt a solution that lets everyone celebrate on January 1, 2000?
If you really, really must be accurate, since timekeeping starts with zero,millennia, centuries and years should begin with the same numbers. The Zerothcentury A.D. ran from 000 to 099, the 19th century from 1900to 1999, and the 20th century will run from 2000 to 2099.The Zeroth millennium A.D. ran from 0000 to 0999, the 1stmillennium from 1000 to 1999, and the 2nd millennium will runfrom 2000 to 2999.
Wait. We're not done yet. When we convert dates to decimal fractions of a year, April1, 1999 becomes 1999.25. We can extend the system to B.C. years; April 1, 2 B.C.(astronomical year -1), becomes -0.75 (-1 + 0.25 = -0.75). This works just finemathematically. But what do we call the year? Calling it -1 seems odd, since thefractional year begins with the digit 0. To have a completely consistent naming system, wewould need a year zero A.D. and a year zero B.C. Below is a timeline. Above it isthe conventional dating system. Below it is the astronomical system, and below that acompletely consistent year naming system.
199 BC 99 BC 4 BC 3 BC 2 BC 1 BC | 1 AD 2AD +---------+----...-----+---------+---------+---------+---------+....-200 -150 -100 -2.5 -2 -1.5 -1 -0.5 0 0.5 1 1.5 2 | Year -2 | Year -1 | Year -0 | Year +0 | Year +1 | |Century-1| Century -0 | Century +0
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Created 10 December 1999, Last Update 10 December 1999
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