Re: The Emacs Calculator and calendar

[Paul Eggert <eggert@cs.ucla.edu>]

On 10/06/2012 11:36 PM, Eli Zaretskii wrote:
>> Date: Sat, 06 Oct 2012 15:07:05 -0700
>> From: Paul Eggert <eggert@cs.ucla.edu>
>>
>> Almost nobody who writes about ancient history specifies dates in the
>> calendars that were used at the time.
> 
> Maybe in English-speaking countries.  Try reading Russian history
> books, and you will see old dates right up to 1918.

I was talking about ancient history, which ended
circa 500.  When Russians write about ancient history,
they typically don't use the same calendars that the
ancients did.  They may use the old (1700-1918) Russian
calendar, but that's not the same thing.

> There are other special cases, some generalization is
> possible.

In theory yes, but it's not practical.
There are too many special cases.  And too many
of these special cases are undocumented: we simply
don't know which calendar was used when and where.

For example, modern historians who write about Caesar's death
usually write in terms of the Julian calendar in effect at the
time.  But this differs from Julian calendar that Emacs
implements.  Caesar was killed on March 15 in the Julian
calendar of the time, and this is probably (though not
certainly) March 14 of the Emacs Julian calendar.  (I write
"not certainly" because some of the details of the old
Julian calendar were lost and have not been reconstructed to
everybody's satisfaction.)