The year before the year 1

Paul Eggert eggert at CS.UCLA.EDU
Wed Aug 11 18:26:35 UTC 2004

"Olson, Arthur David (NIH/NCI)" wrote on 2004-08-11 16:18 UTC:
> Have our standard-making friends said anything on the matter?

For ctime and asctime, the C standard clearly specifies that the years
before 1 are printed as 0, -1, -2,....  It's said that for many years.

Markus Kuhn <Markus.Kuhn at> writes:
> Historical practice was that way simply because the "anno domini"
> technology has allegedly been developped by some monk of the name
> Dionysius Exiguus in the 6th century and was finally rolled-out by the
> church around the year 1000 A.D.

As I understand it we shouldn't blame this on Dionysus Exiguus, as his
system didn't address the issue of numbering years before 1.  The
blame more properly falls on the Venerable Bede, who didn't know about
zero when he extended the system to cover the years before 1 in his
classic work the Ecclesiastical History of the English People,
completed in 731.

The modern computer tradition (e.g., the one used by the ISO, and by
Dershowitz and Reingold's wonderful book "Calendrical Calculations")
is firmly on the side of having a year 0.  This follows in a long
tradition: Cassini, Goethe, Hugo, and others all championed the
year zero.

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