Is 2010 the start of a new decade?

[SirJosephPorter]

I'm ready to concede by "majority rules" that we will be calling years from x0 to x9 a decade, but a "lump of time" would be more accurate. Wasn't Magna Carta 1066 on a calendar? I know back in the 16th century someone did a 9 day adjustment because the seasons were starting to get out of whack.

But would that be according to the calendar we are using now? They were plainly using a different calendar in those days, is 1066 according to that calendar or has it been converted to Gregorian calendar?

And you are right about the 9 days, the perennial problem has been how to divide a year into a complete number of days, without living out any fractions. That is very difficult to do, since the two are unrelated. I think Gregorian calendar does a better job than anybody else in adding leap years and thus keeping the clock in sync (although the leap year formula is very complicated). But before that, people made several attempts to correct for the number of days when calendar got out of whack.

 

[SirJosephPorter]

Technically, yes.

Really? Well, feel free to sue me for copyright violation.

 

[SirJosephPorter]

A lump of time...called a decade. A decade is only a lump of ten years. Zero to nine can be a decade. The problem we have is that the A.D. measurements began with a one and not a zero. I know you were arguing basically what I am at this point, but the part that I quoted was really bothering me.

But how do you know that A.D. measurements began with one and not zero, Swurf? The current calendar goes back only to 1582, the current calendar does not say anything about whether measurements began at 0 or 1. Current calendar says that they began at 1582.

And if you cite some other calendar, that would hardly be relevant to the current Gregorian calendar.

 

[Swurf]

But how do you know that A.D. measurements began with one and not zero, Swurf? The current calendar goes back only to 1582, the current calendar does not say anything about whether measurements began at 0 or 1. Current calendar says that they began at 1582.

And if you cite some other calendar, that would hardly be relevant to the current Gregorian calendar.

From my understanding, A.D. began with its origins from Dionysus Exiguus and its later popularization by Bede. The 1582 reform you mention simply adopted the already-present A.D. measurement.

My main argument has been context, so I understood if we cited a different calendar the context would indeed be different.

 

[Dexter Sinister]

So how do we know that the calendar didn't start at year 0? We don’t.

Yes we do. The year numbering system we use was invented in what we now call 525 C.E. by the monk Dionysius Exiguus (Humble Dennis in modern terms), when the Pope of the day asked him to figure out an easier way to calculate when Easter should be celebrated. He started counting the years at 1, not 0, at what he figured, incorrectly, was the year of Jesus' birth, so it turns out that Jesus was actually born around 4 B.C.E. There have been several adjustments to the calendar since to keep it in line with the seasons, by omitting some days by Papal decree--9 in one case and 17 in another, if my memory is correct--and adding in the extra day every four years except certain century ending years, but it's essentially still Dennis's calendar. Both the Julian and Gregorian calendars use his year numbering system.