Caesarian-Gregorian

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Caesarian-Gregorian

Peter Meyer
Michael Ossipoff said:

> Caesarian-Gregorian is what we’ve got, and examination of its max
> displacement and drift-rate shows that it’s plenty accurate enough.
> ...
> Shouldn’t 30,30,31 with Nearest-Monday have a briefer name?  Maybe
> just 30,30,31 …with the defined-implication that it’s a leap-week
> calendar with the Nearest-Monday year-start rule?

Shouldn't Caesarian-Gregorian have a briefer name?  How about simply
"Gregorian"?  I'm not aware that there is more than one kind of
Gregorian calendar, so prepending "Caesarian" seems to me rather
pointless (and adds an unnecessary four syllables).

Regards,
Peter
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Re: Caesarian-Gregorian

Michael Ossipoff

[quote]

Shouldn't Caesarian-Gregorian have a briefer name?  How about simply
"Gregorian"?  I'm not aware that there is more than one kind of
Gregorian calendar…

[/quote]

.

There is.  _Any_ month system could be used with the Gregorian leapyear-rule.  And it isn’t just hypothetical:

.

Achellis’ World Calendar would have used the Gregorian leap year. So, if Achellis’ proposal were adopted, we’d still be using the Gregorian Calendar, right?  :D

.

Achellis’ proposal should have been called the Gregorian Calendar, right?

.

What’s that you say?  “No, because it wasn’t the only Gregorian calendar”?   Exactly.

.

Probably likewise Eastman’s International Fixed Calendar, etc.

.

[quote]

, so prepending "Caesarian" seems to me rather
pointless (and adds an unnecessary four syllables).

[/quote]

.

Contrary to popular belief, our month system was in use long before Gregorius reformed the leap-year system.

.

Our month-system is Roman.

.

When you look at a calendar on the wall, or leaf through it, there’s nothing about it that gives any indication that it’s “Gregorian”. The prominent and obvious thing about our civil calendar is the months. They’re Roman. …entirely Roman.  …only Roman.

.

To call the standard civil calendar “Gregorian” is an error.

.

It’s the Roman calendar (in its final form, and its only form currently in use), used with a slight modification of its leapyear-rule. Its leapyear rule wasn’t even replaced by a new one. Its original principle was merely carried a step farther.

.

“Gregorian” has four syllables.  “Standard” has two syllables. How many international standard calendars are there?

.

So, if you really want a short name, shouldn’t “Gregorian” have a shorter name? Sure:  “Standard”.

.

Are there places that are considering a different civil calendar? Maybe for local use, but, in our globally-interacting world, every country will continue to use Caesarian-Gregorian for external matters.

.

(…until such time that it’s replaced, which doesn’t seem likely.

.

There are many things and associations, of all sorts, with names of the form:  “_______  and __________”.  In many or most of those instances, those names could be said to be unnecessarily long, because there’s only one such thing with one of the “___________”    in its name.  

.

And it isn’t as if only one calendar is discussed here.  Many are discussed, and the useful descriptive nomenclature that makes sense is to name them by their year-division system and their leap-year (or year-start) system. 

.

Michael Ossipoff

 

 

 


On Sat, Nov 10, 2018 at 8:54 PM Peter Meyer <[hidden email]> wrote:
Michael Ossipoff said:

> Caesarian-Gregorian is what we’ve got, and examination of its max
> displacement and drift-rate shows that it’s plenty accurate enough.
> ...
> Shouldn’t 30,30,31 with Nearest-Monday have a briefer name?  Maybe
> just 30,30,31 …with the defined-implication that it’s a leap-week
> calendar with the Nearest-Monday year-start rule?

Shouldn't Caesarian-Gregorian have a briefer name?  How about simply
"Gregorian"?  I'm not aware that there is more than one kind of
Gregorian calendar, so prepending "Caesarian" seems to me rather
pointless (and adds an unnecessary four syllables).

Regards,
Peter
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Re: Caesarian-Gregorian

Walter J Ziobro
In reply to this post by Peter Meyer

Dear Calendar List

I see Michael's point. I myself have created alternative month Gregorian Calendars and posted them on the wikia Using Michael's logic I could call them Alternating-Month-Gregorian and Equal-Quarter-Gregorian calendars

Walter Ziobro

Sent from AOL Mobile Mail




On Sunday, November 11, 2018 Michael Ossipoff <[hidden email]> wrote:

[quote]

Shouldn't Caesarian-Gregorian have a briefer name?  How about simply
"Gregorian"?  I'm not aware that there is more than one kind of
Gregorian calendar…

[/quote]

.

There is.  _Any_ month system could be used with the Gregorian leapyear-rule.  And it isn’t just hypothetical:

.

Achellis’ World Calendar would have used the Gregorian leap year. So, if Achellis’ proposal were adopted, we’d still be using the Gregorian Calendar, right?  :D

.

Achellis’ proposal should have been called the Gregorian Calendar, right?

.

What’s that you say?  “No, because it wasn’t the only Gregorian calendar”?   Exactly.

.

Probably likewise Eastman’s International Fixed Calendar, etc.

.

[quote]

, so prepending "Caesarian" seems to me rather
pointless (and adds an unnecessary four syllables).

[/quote]

.

Contrary to popular belief, our month system was in use long before Gregorius reformed the leap-year system.

.

Our month-system is Roman.

.

When you look at a calendar on the wall, or leaf through it, there’s nothing about it that gives any indication that it’s “Gregorian”. The prominent and obvious thing about our civil calendar is the months. They’re Roman. …entirely Roman.  …only Roman.

.

To call the standard civil calendar “Gregorian” is an error.

.

It’s the Roman calendar (in its final form, and its only form currently in use), used with a slight modification of its leapyear-rule. Its leapyear rule wasn’t even replaced by a new one. Its original principle was merely carried a step farther.

.

“Gregorian” has four syllables.  “Standard” has two syllables. How many international standard calendars are there?

.

So, if you really want a short name, shouldn’t “Gregorian” have a shorter name? Sure:  “Standard”.

.

Are there places that are considering a different civil calendar? Maybe for local use, but, in our globally-interacting world, every country will continue to use Caesarian-Gregorian for external matters.

.

(…until such time that it’s replaced, which doesn’t seem likely.

.

There are many things and associations, of all sorts, with names of the form:  “_______  and __________”.  In many or most of those instances, those names could be said to be unnecessarily long, because there’s only one such thing with one of the “___________”    in its name.  

.

And it isn’t as if only one calendar is discussed here.  Many are discussed, and the useful descriptive nomenclature that makes sense is to name them by their year-division system and their leap-year (or year-start) system. 

.

Michael Ossipoff

 

 

 


On Sat, Nov 10, 2018 at 8:54 PM Peter Meyer <[hidden email]> wrote:
Michael Ossipoff said:

> Caesarian-Gregorian is what we’ve got, and examination of its max
> displacement and drift-rate shows that it’s plenty accurate enough.
> ...
> Shouldn’t 30,30,31 with Nearest-Monday have a briefer name?  Maybe
> just 30,30,31 …with the defined-implication that it’s a leap-week
> calendar with the Nearest-Monday year-start rule?

Shouldn't Caesarian-Gregorian have a briefer name?  How about simply
"Gregorian"?  I'm not aware that there is more than one kind of
Gregorian calendar, so prepending "Caesarian" seems to me rather
pointless (and adds an unnecessary four syllables).

Regards,
Peter
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Re: Caesarian-Gregorian

Peter Meyer
In reply to this post by Peter Meyer
Michael Ossipoff asserted that there is more than one kind of Gregorian
calendar, and thus that he is justified in using the term
"Caesarian-Gregorian Calendar" to distinguish what is commonly referred
to as "the Gregorian Calendar" from other kinds.  Let us examine this
assertion.

A calendar which identifies a day by means of a (consecutively
numbered) day D within a (consecutively numbered) month M within a
(consecutively numbered) year Y is defined by statements of, or rules
for, the following:

(1)  How many months are in a given numbered year.
(2)  How many days are in a given numbered month in a given numbered year.
(3)  An identification of a particular (empirical) day with a date (Y-M-D).

(3) is required for any calendar to be used in practice, otherwise it
is merely an abstract calendar structure.

In the case of the Gregorian Calendar we have:

(1) Each year has 12 months, numbered consecutively from 1 to 12.
(2) Each month has days numbered consecutively from 1.  Months 1, 3, 4,
5, 6, 7, 8, 9, 10, 11 and 12 have the following number of days
respectively: 31, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31. In year Y
Month 2 has 29 days if Y is divisible by 4 and not divisible by 100, or
Y is divisible by 400, otherwise it has 28 days.  (This is the
Gregorian leap year rule.)
(3) The date '1582-10-15' identifies the day which dawned 159,274 days
prior to today.  Or, what is equivalent, the date '2018-11-12'
identifies today.

A calendar which conforms to only two of (1)-(3) might be regarded as a
'variant' of the Gregorian Calendar if there is a trivial difference,
such as adding a day to June and subtracting a day from July.  Or a
calendar which identifies the date '1-1-1' with the day 43,049 prior to
today. Such variants arouse little interest.

Michael claims that two well-known proposed calendar reforms are
variants of the Gregorian Calendar, namely, the World Calendar and the
International Fixed Calendar.

In the case of the World Calendar, it can be defined as follows:

(1) Each year has 12 months, numbered consecutively from 1 to 12.
(2) Each month has days numbered consecutively from 1.  Months 1, 4, 7,
10 and 12 have 31 days, and the other months have 30 days, except that
in year Y Month 6 has 31 days if Y is divisible by 4 and not divisible
by 100, or Y is divisible by 400, otherwise it has 30 days.  (This is a
variant of the Gregorian leap year rule.)
(3) [The correlation was not finalized.]

This calendar is not a variant of the Gregorian Calendar, because the
numbers of days within each of the 12 months differs widely from those
of the Gregorian Calendar, and the leap year rule is applied to the 6th
month and not to the 2nd month.

In the case of the International Fixed Calendar, it can be defined as follows:

(1) Each year has 13 months, numbered consecutively from 1 to 13.
(2) Each month has days numbered consecutively from 1 to 28, except
that Month 13 has 29 days, and in Year Y Month 6 has 29 days if Y is
divisible by 4 and not divisible by 100, or Y is divisible by 400,
otherwise it has 28 days.  (This is a another variant of the Gregorian
leap year rule.)
(3) [The correlation was not finalized.]

This calendar is not a variant of the Gregorian Calendar, because it
has 13 months instead of 12, the numbers of days within each of the
months differs widely from those of the Gregorian Calendar, and the
leap year rule is applied to the 6th month and not to the 2nd month.

The use in a calendar of the Gregorian leap year rule, or a variant
thereof, does not justify asserting that the calendar is a variant of
the Gregorian Calendar and thus does not justify calling the calendar
the X-Gregorian Calendar, for some 'X'.  Thus it is pointless to call
the Gregorian Calendar the "Caesarian-Gregorian Calendar" because there
are no calendars (worthy of consideration) which can properly be called
'variants' of the Gregorian Calendar.

Regards,
Peter Meyer
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Re: Caesarian-Gregorian

k.palmen@btinternet.com
Dear Peter and Calendar People

From earlier E-mails, I recall Michael defined two features of a calendar
(a) The year structure, which is essentially a list of dates for each type of year common and leap
(b) A rule that tells you which day each year begins, which may take the form of a leap year rule and an epoch/correlation rule.

Peter's (1) belongs to (a) and (3) belongs to (b). (2) divides between (a) and (b) as follows:

(2a) Each month has days numbered consecutively from 1.  Months 1, 3, 4,
5, 6, 7, 8, 9, 10, 11 and 12 have the following number of days
respectively: 31, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31.
Month 2 has 28 days in a common year and 29 days in a leap year.

(2b) Year Y is a leap year, if Y is divisible by 4 and not divisible by 100, or
Y is divisible by 400, otherwise it is a common year.  (This 2b is the
Gregorian leap year rule.)


Michael has used Gregorian for the Gregorian year start rule (b), which could also apply to the World Calendar or International Fixed Calendar. He uses Caesarian (and formerly Roman) for the Gregorian year structure, which is also used by the Julian calendar.

Michael has the opinion that "Gregorian" should only be used for the year start rule rather than the entire calendar and the complete calendar should be qualified by a year structure name in this case Caesarian.

I take a different view. If one wants to communicate calendar reform, one must use existing terminology to be understood. If you are not understood, your calendar reform will not succeed. Conventional terminology names entire calendar systems rather than year structures and year start rules. If one wants to refer to a particular year structure (YS) or year start rule (YSR), one can do so by taking a name from a calendar that uses it (the first or most common such calendar). E.g. Julian YS or Gregorian YSR. The YS or YSR can be dropped if the context makes it clear.

Karl

Monday Gamma November 2018


----Original message----
From : [hidden email]
Date : 12/11/2018 - 11:09 (GMT)
To : [hidden email]
Subject : Re: Caesarian-Gregorian

Michael Ossipoff asserted that there is more than one kind of Gregorian
calendar, and thus that he is justified in using the term
"Caesarian-Gregorian Calendar" to distinguish what is commonly referred
to as "the Gregorian Calendar" from other kinds.  Let us examine this
assertion.

A calendar which identifies a day by means of a (consecutively
numbered) day D within a (consecutively numbered) month M within a
(consecutively numbered) year Y is defined by statements of, or rules
for, the following:

(1)  How many months are in a given numbered year.
(2)  How many days are in a given numbered month in a given numbered year.
(3)  An identification of a particular (empirical) day with a date (Y-M-D).

(3) is required for any calendar to be used in practice, otherwise it
is merely an abstract calendar structure.

In the case of the Gregorian Calendar we have:

(1) Each year has 12 months, numbered consecutively from 1 to 12.
(2) Each month has days numbered consecutively from 1.  Months 1, 3, 4,
5, 6, 7, 8, 9, 10, 11 and 12 have the following number of days
respectively: 31, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31. In year Y
Month 2 has 29 days if Y is divisible by 4 and not divisible by 100, or
Y is divisible by 400, otherwise it has 28 days.  (This is the
Gregorian leap year rule.)
(3) The date '1582-10-15' identifies the day which dawned 159,274 days
prior to today.  Or, what is equivalent, the date '2018-11-12'
identifies today.

A calendar which conforms to only two of (1)-(3) might be regarded as a
'variant' of the Gregorian Calendar if there is a trivial difference,
such as adding a day to June and subtracting a day from July.  Or a
calendar which identifies the date '1-1-1' with the day 43,049 prior to
today. Such variants arouse little interest.

Michael claims that two well-known proposed calendar reforms are
variants of the Gregorian Calendar, namely, the World Calendar and the
International Fixed Calendar.

In the case of the World Calendar, it can be defined as follows:

(1) Each year has 12 months, numbered consecutively from 1 to 12.
(2) Each month has days numbered consecutively from 1.  Months 1, 4, 7,
10 and 12 have 31 days, and the other months have 30 days, except that
in year Y Month 6 has 31 days if Y is divisible by 4 and not divisible
by 100, or Y is divisible by 400, otherwise it has 30 days.  (This is a
variant of the Gregorian leap year rule.)
(3) [The correlation was not finalized.]

This calendar is not a variant of the Gregorian Calendar, because the
numbers of days within each of the 12 months differs widely from those
of the Gregorian Calendar, and the leap year rule is applied to the 6th
month and not to the 2nd month.

In the case of the International Fixed Calendar, it can be defined as follows:

(1) Each year has 13 months, numbered consecutively from 1 to 13.
(2) Each month has days numbered consecutively from 1 to 28, except
that Month 13 has 29 days, and in Year Y Month 6 has 29 days if Y is
divisible by 4 and not divisible by 100, or Y is divisible by 400,
otherwise it has 28 days.  (This is a another variant of the Gregorian
leap year rule.)
(3) [The correlation was not finalized.]

This calendar is not a variant of the Gregorian Calendar, because it
has 13 months instead of 12, the numbers of days within each of the
months differs widely from those of the Gregorian Calendar, and the
leap year rule is applied to the 6th month and not to the 2nd month.

The use in a calendar of the Gregorian leap year rule, or a variant
thereof, does not justify asserting that the calendar is a variant of
the Gregorian Calendar and thus does not justify calling the calendar
the X-Gregorian Calendar, for some 'X'.  Thus it is pointless to call
the Gregorian Calendar the "Caesarian-Gregorian Calendar" because there
are no calendars (worthy of consideration) which can properly be called
'variants' of the Gregorian Calendar.

Regards,
Peter Meyer
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Re: Caesarian-Gregorian

Michael Ossipoff
In reply to this post by Peter Meyer

[quote]
A calendar which identifies a day by means of a (consecutively
numbered) day D within a (consecutively numbered) month M within a
(consecutively numbered) year Y is defined by statements of, or rules
for, the following:

.

(1)  How many months are in a given numbered year.
(2)  How many days are in a given numbered month in a given numbered year.
(3)  An identification of a particular (empirical) day with a date (Y-M-D).

.

(3) is required for any calendar to be used in practice, otherwise it
is merely an abstract calendar structure.

[/quote]

.

That isn’t general, because, for example, ISO WeekDate doen’t use months.
.

[quote]
Michael claims that two well-known proposed calendar reforms are
variants of the Gregorian Calendar, namely, the World Calendar and the
International Fixed Calendar.

[/quote]

Michael points out that they’re as “Gregorian” as is our current standard civil calendar, by virtue of their use of the Gregorian leapyear-rule.  (…unless you think that the Caesarian months are “Gregorian” because Gregorius didn’t eliminate or replace them.)

.

[quote]

In the case of the World Calendar…

[…]

This calendar is not a variant of the Gregorian Calendar, because the
numbers of days within each of the 12 months differs widely from those
of the Gregorian Calendar, and the leap year rule is applied to the 6th
month and not to the 2nd month.

[/quote]

.

In other words, Peter is circularly using the assumption that Gregorian-ness requires the use of Caesarian months, because “the Gregorian Calendar” uses Caesarian months, to support a claim that the World Calendar isn’t Gregorian, to support a claim that Caesarian-Gregorian is the only Gregorian Calendar, to support a claim that Caesarian-Gregorian is _the_ Gregorian Calendar.

.

…a claim that is assumed by the “because” clause of the first assertion in the above paragraph.

.

(Likewise for International Fixed Calendar.)

.

Michael Ossipoff


On Mon, Nov 12, 2018 at 6:09 AM Peter Meyer <[hidden email]> wrote:
Michael Ossipoff asserted that there is more than one kind of Gregorian
calendar, and thus that he is justified in using the term
"Caesarian-Gregorian Calendar" to distinguish what is commonly referred
to as "the Gregorian Calendar" from other kinds.  Let us examine this
assertion.

A calendar which identifies a day by means of a (consecutively
numbered) day D within a (consecutively numbered) month M within a
(consecutively numbered) year Y is defined by statements of, or rules
for, the following:

(1)  How many months are in a given numbered year.
(2)  How many days are in a given numbered month in a given numbered year.
(3)  An identification of a particular (empirical) day with a date (Y-M-D).

(3) is required for any calendar to be used in practice, otherwise it
is merely an abstract calendar structure.

In the case of the Gregorian Calendar we have:

(1) Each year has 12 months, numbered consecutively from 1 to 12.
(2) Each month has days numbered consecutively from 1.  Months 1, 3, 4,
5, 6, 7, 8, 9, 10, 11 and 12 have the following number of days
respectively: 31, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31. In year Y
Month 2 has 29 days if Y is divisible by 4 and not divisible by 100, or
Y is divisible by 400, otherwise it has 28 days.  (This is the
Gregorian leap year rule.)
(3) The date '1582-10-15' identifies the day which dawned 159,274 days
prior to today.  Or, what is equivalent, the date '2018-11-12'
identifies today.

A calendar which conforms to only two of (1)-(3) might be regarded as a
'variant' of the Gregorian Calendar if there is a trivial difference,
such as adding a day to June and subtracting a day from July.  Or a
calendar which identifies the date '1-1-1' with the day 43,049 prior to
today. Such variants arouse little interest.

Michael claims that two well-known proposed calendar reforms are
variants of the Gregorian Calendar, namely, the World Calendar and the
International Fixed Calendar.

In the case of the World Calendar, it can be defined as follows:

(1) Each year has 12 months, numbered consecutively from 1 to 12.
(2) Each month has days numbered consecutively from 1.  Months 1, 4, 7,
10 and 12 have 31 days, and the other months have 30 days, except that
in year Y Month 6 has 31 days if Y is divisible by 4 and not divisible
by 100, or Y is divisible by 400, otherwise it has 30 days.  (This is a
variant of the Gregorian leap year rule.)
(3) [The correlation was not finalized.]

This calendar is not a variant of the Gregorian Calendar, because the
numbers of days within each of the 12 months differs widely from those
of the Gregorian Calendar, and the leap year rule is applied to the 6th
month and not to the 2nd month.

In the case of the International Fixed Calendar, it can be defined as follows:

(1) Each year has 13 months, numbered consecutively from 1 to 13.
(2) Each month has days numbered consecutively from 1 to 28, except
that Month 13 has 29 days, and in Year Y Month 6 has 29 days if Y is
divisible by 4 and not divisible by 100, or Y is divisible by 400,
otherwise it has 28 days.  (This is a another variant of the Gregorian
leap year rule.)
(3) [The correlation was not finalized.]

This calendar is not a variant of the Gregorian Calendar, because it
has 13 months instead of 12, the numbers of days within each of the
months differs widely from those of the Gregorian Calendar, and the
leap year rule is applied to the 6th month and not to the 2nd month.

The use in a calendar of the Gregorian leap year rule, or a variant
thereof, does not justify asserting that the calendar is a variant of
the Gregorian Calendar and thus does not justify calling the calendar
the X-Gregorian Calendar, for some 'X'.  Thus it is pointless to call
the Gregorian Calendar the "Caesarian-Gregorian Calendar" because there
are no calendars (worthy of consideration) which can properly be called
'variants' of the Gregorian Calendar.

Regards,
Peter Meyer
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Re: Caesarian-Gregorian

Michael Ossipoff
In reply to this post by k.palmen@btinternet.com
Carl said:

[quote]
If one wants to communicate calendar reform, one must use existing terminology to be understood. If you are not understood, your calendar reform will not succeed.
[/quote]

No, calendar-reform has much bigger problems than the popular miconception that there's such a thing as a Gregorian month-system or that the Caesarian-Gregorian Calendar is entirely Gregorian.

...like how about the fact that no one cares about the conveniences that the reform-calendars would bring?

[quote]
Conventional terminology names entire calendar systems rather than year structures and year start rules.
[/quote]

Then "conventional terminology" requires people to know in advance which whole set of attributes goes with each non-descriptive name.

...as opposed to using a descriptive name that names a calendar by its month-system and year-start system attributes.

Such a descriptive name would be more obvious regarding what it refers to.

By the way, Karl said, in a different thread, that I've replaced "Roman-Gregorian" with "Caesarian-Gregorian".

Yes, because there was less objection to "Caesarian-Gregorian".

But I prefer "Roman-Gregorian".   "Roman" has half as many syllables as "Caesarian", and won't be confused with an emergency birth procedure.

There was the objection that there were various other Roman month-systems before the Carsarian month-system. Yes, but only one of those was the final one that the Romans arrived at.    ...and only one of those is currently (...or was receently) used or proposed.

(..in contrast to the fact that several other calendars with the Gregorian leapyear-rule were and are proposed.)

Michael Ossipoff



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Re: Caesarian-Gregorian

Peter Meyer
In reply to this post by Peter Meyer
Michael Ossipoff quotes me:

> [quote]
> A calendar which identifies a day by means of a (consecutively
> numbered) day D within a (consecutively numbered) month M within a
> (consecutively numbered) year Y is defined by statements of, or rules
> for, the following:

and then comments:

> That isn’t general, because, for example, ISO WeekDate doen’t use months.

My statement was not intended to be a general characterization of
calendars.  Michael has overlooked (or ignored) the fact that I wrote,
"A calendar which identifies a ... day D within a ... month M ..." , so
obviously I was not attempting to include calendars which don't use
months.

Later Michael continues:

> In other words, Peter is circularly using the assumption that
> Gregorian-ness requires ...

"Gregorian-ness" seems to have been a concept invented by Michael just
prior to his writing this.  Nothing I wrote uses or presupposes that
(spurious) concept.

Referring to the World Calendar and the  International Fixed Calendar
Michael asserts that
> they’re as “Gregorian” as is our current standard civil
> calendar, by virtue of their use of the Gregorian leapyear-rule.

He is here trying to persuade us to adopt a new definition of
"Gregorian" as it refers to calendars.  Karl has pointed out that this
would help no-one, except perhaps Michael in his attempt to get us to
rename (spuriously) the Gregorian Calendar as the "Caesarian-Gregorian
Calendar".

Regards,
Peter Meyer