FOM: (no subject)
Miguel A. Lerma
mlerma at math.northwestern.edu
Mon Feb 18 15:03:25 EST 2002
> I disagree that this was the only reason to celebrate on 1/1/2000
rather than 1/1/2001.
My point is that avoiding social isolation was the only reason
expressed by my colleague, and that is why I mentioned the anecdote
as an example of the effect of social pressure.
> The assertion "there was no year zero" is
simply a statement about the mathematical sophistication of people
several centuries later, the people who lived at the time used an
entirely different calendar. I am allowed to regard the year "1 B.C."
as having the alternate name "0", the year "2 B.C." as having the
alternate name "-1", and so on, since neither notation has the
sanction of having been used contemporaneously . (Indeed, this is
probably how historical computer databases represent dates.)
Yes, that is the way astronomers count time. But according to the
U.S. Naval Observatory (the main time keeper authority of the U.S.)
the globally recognized Gregorian calendar still starts on January 1,
1 Anno Domini:
> It is the case that some people, deemed "authorities" by some other
people, defined "the 20th Century" to comprise the years 1901-2000,
but there is no reason I can't say that the "1st century" consisted of
the years 0-99 rather than 1-100 and "the 3rd millennium" began in
Besides starting the calendar in year 0 instead of year 1 many other
interesting changes have been suggested, but calendar reform seems to
be a very hard issue.
> Nobody living in that era had ever defined "the first century"
since the modern reckoning wasn't even used for those dates for
several hundred years afterwards. The pedantic self-appointed
authorities would enshrine a primitive method of reckoning because
some ancient monks didn't have the concept of the number zero, but
"century" and "millennium" do not have an official definition in our
calendar so they may be ignored.
The dictionary definitions of "century" and "millennium" should
> The only person who REALLY has the authority to make such
declarations is the successor of the person who invented and
officially proclaimed our current "Gregorian" method of reckoning
years and dates, but Pope John Paul II finessed the issue by, in his
apostolic letter "Tertio Millennio adveniente" on November 10, 1994,
declaring the entire year 2000 to be a jubilee year and scheduling
celebrations throughout the whole year, carefully avoiding saying
whether 2000 represented the first year of the third millennium or the
last year of the second millennium.
The history of the slow acceptance of the Gregorian reform shows that
authority on these matters is a rather polemic issue. In any case in
these times of church and state separation no religious authority
would have much weight in decisions concerning calendar reform.
Nowadays any reform would require agreement among all local
authoritative time keepers.
Miguel A. Lerma
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