Perpetual calendar for the world

[Peace Crusader]

20111231.0840

Dear Calendar People,

This is quoted from Reader’s Digest, January 1955 issue, page 102, which my father kept:

“In 1923 the League of Nations began to examine 185 different calendar plans.  One split the year into 73 weeks of five days each – the days to be called Ano, Beno, Ceno, Deno, Eno.  Another had 20 months, with some weeks six days long, others seven.  The League narrowed the plans down to the two which seemed to have the least number of tricky artificialities: the 12-month, equal-quarter World Calendar; and a 13-month scheme (the extra month, called Sol, was to be inserted between June and July).”

Like before, there are many different calendar plans today.  But I think, when the United Nations Economic and Social Council decides which calendar plan is best suited for the world to use, it will be narrowed down to a 12-month, equal-quarter and a 13-month schemes.

Best regards,

Aristeo Canlas Fernando, Peace Crusader and Echo of the Holy Spirit
Motto: pro aris et focis (for the sake of, or defense of, religion and home)
http://aristean.org/ and http://peacecrusader.wordpress.com/
"The Internet is mightier than the sword."

[Peace Crusader]

20111231.1540

Dear Calendar People,

Reader’s Digest, January 1955 issue, condensed the article it published from The Saturday Revew, December 18, 1954 titled “Let’s End Our Calendar Chaos” by Lacy Donnell.  Here is the link:  http://www.unz.org/Publication/SaturdayRev-1954dec18-00009?View=PDF&apages=0009

and its continuation from page 35 to 37 at http://www.unz.org/Publication/SaturdayRev-1954dec18-00009?View=PDF

Best regards,
Aristeo Canlas Fernando, Peace Crusader and Echo of the Holy Spirit
Motto: pro aris et focis (for the sake of, or defense of, religion and home)
http://aristean.org/ and http://peacecrusader.wordpress.com/
"The Internet is mightier than the sword."

----- Forwarded Message -----
From: Aristeo Fernando <peacecrusader888@...>
To: "CALNDR-L@..." <CALNDR-L@...>
Sent: Saturday, December 31, 2011 9:02 AM
Subject: Perpetual calendar for the world

20111231.0840

Dear Calendar People,

This is quoted from Reader’s Digest, January 1955 issue, page 102, which my father kept:

“In 1923 the League of Nations began to examine 185 different calendar plans.  One split the year into 73 weeks of five days each – the days to be called Ano, Beno, Ceno, Deno, Eno.  Another had 20 months, with some weeks six days long, others seven.  The League narrowed the plans down to the two which seemed to have the least number of tricky artificialities: the 12-month, equal-quarter World Calendar; and a 13-month scheme (the extra month, called Sol, was to be inserted between June and July).”

Like before, there are many different calendar plans today.  But I think, when the United Nations Economic and Social Council decides which calendar plan is best suited for the world to use, it will be narrowed down to a 12-month, equal-quarter and a 13-month schemes.

Best regards,

Aristeo Canlas Fernando, Peace Crusader and Echo of the Holy Spirit
Motto: pro aris et focis (for the sake of, or defense of, religion and home)
http://aristean.org/ and http://peacecrusader.wordpress.com/
"The Internet is mightier than the sword."

[Peter Zilahy Ingerman, PhD]

Sonny, it is YOUR opinion that "The calendar list needs to come together on a consensus for a perpetual calendar and then start advocating it to our political leaders."  It may also be the opinion of a few others on this list, but it is certainly not my opinion, and I believe is  not the opinion of  a number of others.

If you want to establish your own listserve for you and those of like mind, you are certainly welcome to do so, but I shall be happy not to join it, and have no interest in apodictic arrogance.

Pzed

On 2011-12-31 10:17, Sonny Pondrom wrote:

Dear Aristeo and Calendar People,

I liked and recommend this article, although I could not get the page 35 to display.  The calendar list needs to come together on a consensus for a perpetual calendar and then start advocating it to our political leaders.  I nominate the World calendar as a starting point.  This is the calendar that first got my attention.  I have been working on improvements ever since, but really would accept the many of the others.  

Sonny Pondromsonny@..."Happy New Year" 

On Dec 31, 2011, at 1:48 AM, Aristeo Fernando wrote:

20111231.1540

Dear Calendar People,

Reader’s Digest, January 1955 issue, condensed the article it published from The Saturday Revew, December 18, 1954 titled “Let’s End Our Calendar Chaos” by Lacy Donnell.  Here is the link:  http://www.unz.org/Publication/SaturdayRev-1954dec18-00009?View=PDF&apages=0009

and its continuation from page 35 to 37 at http://www.unz.org/Publication/SaturdayRev-1954dec18-00009?View=PDF

Best regards,
Aristeo Canlas Fernando, Peace Crusader and Echo of the Holy Spirit
Motto: pro aris et focis (for the sake of, or defense of, religion and home)
http://aristean.org/ and http://peacecrusader.wordpress.com/
"The Internet is mightier than the sword."

----- Forwarded Message -----
From: Aristeo Fernando <peacecrusader888@...>
To: "CALNDR-L@..." <CALNDR-L@...>
Sent: Saturday, December 31, 2011 9:02 AM
Subject: Perpetual calendar for the world

20111231.0840

Dear Calendar People,

This is quoted from Reader’s Digest, January 1955 issue, page 102, which my father kept:

“In 1923 the League of Nations began to examine 185 different calendar plans.  One split the year into 73 weeks of five days each – the days to be called Ano, Beno, Ceno, Deno, Eno.  Another had 20 months, with some weeks six days long, others seven.  The League narrowed the plans down to the two which seemed to have the least number of tricky artificialities: the 12-month, equal-quarter World Calendar; and a 13-month scheme (the extra month, called Sol, was to be inserted between June and July).”

Like before, there are many different calendar plans today.  But I think, when the United Nations Economic and Social Council decides which calendar plan is best suited for the world to use, it will be narrowed down to a 12-month, equal-quarter and a 13-month schemes.

Best regards,

Aristeo Canlas Fernando, Peace Crusader and Echo of the Holy Spirit
Motto: pro aris et focis (for the sake of, or defense of, religion and home)
http://aristean.org/ and http://peacecrusader.wordpress.com/
"The Internet is mightier than the sword."

[Dean Gahlon]

Sonny, I'll add my voice to those on this list who are *not* interested in
calendar reform. Although I will grant that some members of this list are so
interested, I don't think you can assume that everyone on this list is.

As an additional issue, could you please trim the amount of quoted text from
your messages, particularly when it no longer has anything to do with what you
are saying?

Dean

[Jerome H. Fine]

 >Dean Gahlon wrote:

>Sonny, I'll add my voice to those on this list who are *not* interested in
>calendar reform. Although I will grant that some members of this list are so
>interested, I don't think you can assume that everyone on this list is.
>  
>
I strongly agree with this point of view for at least the next 1000 years.
Based on the data that Irv has provided, there does not seem to be
any point in making changes which are not essential when all of the
other negative aspects of society are considered.

In the long term, however (perhaps more than 2000 years, certainly
around 10000 years), some changes will likely be essential.  It is
probably best to wait at least a 100 years, maybe even 500 years,
to see just what unexpected changes do take place along with
verification of the long term trends that Irv suggests are likely
to take place.  Of course, during the next 500 years, there
may be 2 world wars - the second using rocks as ammunition
and calendar reform will be the last thing that anyone thinks
about.  If society can manage to handle the technology
explosion during the next 500 years and develop new social
concepts along with the responsible behaviour to take advantage
of the new relationships, the current aspects which make it
essential to have a continuous 7 day week may also fade
and the proposals by Sonny may actually be acceptable.

>As an additional issue, could you please trim the amount of quoted text from
>your messages, particularly when it no longer has anything to do with what you
>are saying?
>
I almost automatically delete any post to the list which is
larger than 100 K, so if you want your posts read (which
I presume is true or you would not spend the time to
compose them), then please restrict the size to essential
aspects.

If there are essential charts and diagrams which can be
seen on a web site, then just include the address and we
can choose to look or not by ourselves.

Jerome Fine

[Irv Bromberg]

On 2011 Dec 31, at 20:07 , Jerome H. Fine wrote:

>Dean Gahlon wrote:

I'll add my voice to those on this list who are *not* interested in calendar reform.

Although I will grant that some members of this list are so interested, I don't think you can assume that everyone on this list is.

I strongly agree with this point of view for at least the next 1000 years.
Based on the data that Irv has provided, there does not seem to be
any point in making changes which are not essential when all of the
other negative aspects of society are considered.

Irv replies:  Jerome you are looking only at the astronomical drift, which I agree, in the case of the Gregorian calendar, is not important for a while.

My primary interest in reforming the Gregorian calendar is to make it perpetual, for all the scheduling advantages that that entails, savings which would be realized immediately and for all time.  This can be accomplished without disrupting the traditional 7-day weekly cycle if a leap week is employed at appropriate intervals instead of a leap day at appropriate intervals.  I have no interest whatsoever in any Gregorian calendar reform proposal that fails to make the calendar perpetual or fails to conserve the traditional 7-day weekly cycle.

While we are at it making it into a perpetual calendar, however, we may as well fix, improve, and optimize all aspects of the calendar so that we are really pleased with the final result.  Here I include ideas like making the month lengths consistent and symmetrical, making the same day number in every month the same weekday, employing a symmetrical smoothly spread single-step leap rule, putting the leap week at the end of the year so that the annual ordinal day number of every date is permanently fixed, and choosing a leap cycle that yields an intentionally slightly short calendar mean year.  (Not listed in order of priority.)

The cost of implementing comprehensive reform is probably no greater than a so-called "minimal" change, because as soon as the calendar arithmetic changes, it requires software to be adjusted, and most of the cost is due to having to do anything to accommodate the new calendar.

-- Dr. Irv Bromberg, University of Toronto, Canada

<http://www.sym454.org/>

[Peace Crusader]

20120101.1335

Dear Sonny and Calendar People,

I am very sorry that the address for page 35 did not work.  I thought that was the address when I was on page 35. 

From page 9 where the article started, just click NEXT PAGE until you reach page 35.

I agree with you that “the calendar list needs to come together on a consensus for a perpetual calendar and then start advocating it to our political leaders.”  It has been since 1956-04-20, more than 55 years ago, when the United Nation’s Economic and Social Council adjourned the discussion on calendar reform sine die (or without fixing a day for future action or meeting).

Best regards,

Aristeo Canlas Fernando, Peace Crusader and Echo of the Holy Spirit
Motto: pro aris et focis (for the sake of, or defense of, religion and home)
http://aristean.org/ and http://peacecrusader.wordpress.com/
"The Internet is mightier than the sword."

From: Sonny Pondrom <sonny@...>
To: CALNDR-L@...
Sent: Sunday, January 1, 2012 1:17 AM
Subject: Re: Perpetual calendar for the world

Dear Aristeo and Calendar People,

I liked and recommend this article, although I could not get the page 35 to display.  The calendar list needs to come together on a consensus for a perpetual calendar and then start advocating it to our political leaders.  I nominate the World calendar as a starting point.  This is the calendar that first got my attention.  I have been working on improvements ever since, but really would accept the many of the others.  

Sonny Pondrom

sonny@...

2011-Q4-W13-D6

"Happy New Year"

 

< /DIV>

On Dec 31, 2011, at 1:48 AM, Aristeo Fernando wrote:

20111231.1540

Dear Calendar People,

Reader’s Digest, January 1955 issue, condensed the article it published from The Saturday Revew, December 18, 1954 titled “Let’s End Our Calendar Chaos” by Lacy Donnell.  Here is the link:  http://www.unz.org/Publication/SaturdayRev-1954dec18-00009?View=PDF&apages=0009

and its continuation from page 35 to 37 at http://www.unz.org/Publication/SaturdayRev-1954dec18-00009?View=PDF

Best regards,
Aristeo Canlas Fernando, Peace Crusader and Echo of the Holy Spirit
Motto: pro aris et focis (for the sake of, or defense of, religion and home)
http://aristean.org/ and http://peacecrusader.wordpress.com/
"The Internet is mightier than the sword."

----- Forwarded Message -----
From: Aristeo Fernando <peacecrusader888@...>
To: "CALNDR-L@..." <CALNDR-L@...>
Sent: Saturday, December 31, 2011 9:02 AM
Subject: Perpetual calendar for the world

20111231.0840

Dear Calendar People,

This is quoted from Reader’s Digest, January 1955 issue, page 102, which my father kept:

“In 1923 the League of Nations began to examine 185 different calendar plans.  One split the year into 73 weeks of five days each – the days to be called Ano, Beno, Ceno, Deno, Eno.  Another had 20 months, with some weeks six days long, others seven.  The League narrowed the plans down to the two which seemed to have the least number of tricky artificialities: the 12-month, equal-quarter World Calendar; and a 13-month scheme (the extra month, called Sol, was to be inserted between June and July).”

Like before, there are many different calendar plans today.  But I think, when the United Nations Economic and Social Council decides which calendar plan is best suited for the world to use, it will be narrowed down to a 12-month, equal-quarter and a 13-month schemes.

Best regards,

Aristeo Canlas Fernando, Peace Crusader and Echo of the Holy Spirit
Motto: pro aris et focis (for the sake of, or defense of, religion and home)
http://aristean.org/ and http://peacecrusader.wordpress.com/
"The Internet is mightier than the sword."

[Peace Crusader]

20120101.2230

Dear Sonny and Calendar People,

Please try the following to go to page 35 of The Saturday Review:

 http://www.unz.org/Publication/SaturdayRev-1954dec18-00009?View=PDF&pages=0035

Then, just press NEXT PAGE to go to page 36, and press it again to go to page 37.

Best regards,
Aristeo Canlas Fernando, Peace Crusader and Echo of the Holy Spirit
Motto: pro aris et focis (for the sake of, or defense of, religion and home)
http://aristean.org/ and http://peacecrusader.wordpress.com/
"The Internet is mightier than the sword."

From: Sonny Pondrom <sonny@...>
To: CALNDR-L@...
Sent: Sunday, January 1, 2012 1:17 AM
Subject: Re: Perpetual calendar for the world

Dear Aristeo and Calendar People,

I liked and recommend this article, although I could not get the page 35 to display.  The calendar list needs to come together on a consensus for a perpetual calendar and then start advocating it to our political leaders.  I nominate the World calendar as a starting point.  This is the calendar that first got my attention.  I have been working on improvements ever since, but really would accept the many of the others.  

Sonny Pondrom

sonny@...

2011-Q4-W13-D6

"Happy New Year"

 

< /DIV>

On Dec 31, 2011, at 1:48 AM, Aristeo Fernando wrote:

20111231.1540

Dear Calendar People,

Reader’s Digest, January 1955 issue, condensed the article it published from The Saturday Revew, December 18, 1954 titled “Let’s End Our Calendar Chaos” by Lacy Donnell.  Here is the link:  http://www.unz.org/Publication/SaturdayRev-1954dec18-00009?View=PDF&apages=0009

and its continuation from page 35 to 37 at http://www.unz.org/Publication/SaturdayRev-1954dec18-00009?View=PDF

Best regards,
Aristeo Canlas Fernando, Peace Crusader and Echo of the Holy Spirit
Motto: pro aris et focis (for the sake of, or defense of, religion and home)
http://aristean.org/ and http://peacecrusader.wordpress.com/
"The Internet is mightier than the sword."

----- Forwarded Message -----
From: Aristeo Fernando <peacecrusader888@...>
To: "CALNDR-L@..." <CALNDR-L@...>
Sent: Saturday, December 31, 2011 9:02 AM
Subject: Perpetual calendar for the world

20111231.0840

Dear Calendar People,

This is quoted from Reader’s Digest, January 1955 issue, page 102, which my father kept:

“In 1923 the League of Nations began to examine 185 different calendar plans.  One split the year into 73 weeks of five days each – the days to be called Ano, Beno, Ceno, Deno, Eno.  Another had 20 months, with some weeks six days long, others seven.  The League narrowed the plans down to the two which seemed to have the least number of tricky artificialities: the 12-month, equal-quarter World Calendar; and a 13-month scheme (the extra month, called Sol, was to be inserted between June and July).”

Like before, there are many different calendar plans today.  But I think, when the United Nations Economic and Social Council decides which calendar plan is best suited for the world to use, it will be narrowed down to a 12-month, equal-quarter and a 13-month schemes.

Best regards,

Aristeo Canlas Fernando, Peace Crusader and Echo of the Holy Spirit
Motto: pro aris et focis (for the sake of, or defense of, religion and home)
http://aristean.org/ and http://peacecrusader.wordpress.com/
"The Internet is mightier than the sword."

[Irv Bromberg]

On 2012 Jan 1, at 04:34 , Sonny Pondrom wrote:

But instead of having 4 months with 35 days, can anyone think of an acceptable way to make 28 days the maximum length?

It is easy to implement a 13-month calendar with leap week instead of null days.

But then the calendar doesn't divide into 4 equal quarters without chopping months.

So I took that 13th month and distributed one of its weeks to each quarter of the year, yielding the Symmetry454 calendar.

-- Dr. Irv Bromberg, University of Toronto, Canada

<http://www.sym454.org/>

[Irv Bromberg]

On Jan 1, 2012, at 7:49 AM, Irv Bromberg wrote:

It is easy to implement a 13-month calendar with leap week instead of null days.

But then the calendar doesn't divide into 4 equal quarters without chopping months.

On 2012 Jan 1, at 13:27 , Sonny Pondrom wrote:

If dates included quarters and weeks, then a quarter ends after 13 weeks.   If dates include just weeks, then 13, 26, 39 and 52 ends each quarter.   Note, the ISO-8601 Week Date calendar does this.  But, there is an occasional week 53 because Week 1 must have a Thursdays.

If you are happy to do away with months, then the calendar reform is already done = the ISO calendar!

Sonny continued:  This problem will likely go away with a perpetual calendar.

Now you have me really confused.  The ISO calendar is a leap week perpetual calendar.  That leap week occurs once every 6 or 5 years, but due to its parallel relationship with the Gregorian calendar there is a 7-year interval once per 400 years (spanning the 300th year of each cycle).  This leap week is not going to "go away", and nobody will accept a null-day perpetual modification of the ISO calendar.

-- Dr. Irv Bromberg, University of Toronto, Canada

<http://www.sym454.org/>

[Irv Bromberg]

On Jan 1, 2012, at 2:44 PM, Irv Bromberg wrote:

The ISO calendar is a leap week perpetual calendar.

On 2012 Jan 1, at 22:55 , Sonny Pondrom wrote:

What calendar are you referring to - ISO-8601?

Irv replies:  Yes, there is no other ISO calendar.

-- Dr. Irv Bromberg, University of Toronto, Canada

<http://www.sym454.org/>

[Irv Bromberg]

On 2012 Jan 2, at 09:16 , Sonny Pondrom wrote:

Irv, how do you define a leap week perpetual calendar?  

Irv replies:

• traditional 7-day week
• 52 weeks per common year
• leap years have a 53rd week appended to the end of the year, occurring once every 6 or 5 years (71 leap weeks per 400 years in the case of the ISO calendar, average leap week interval exactly 293+68/71 weeks)
• start every year on a specified weekday (Monday in the case of the ISO calendar)

Because the ISO calendar starts every year on Monday, it is a perpetual calendar.  Every year is the same except for the occasional 53rd week.

Non-lunisolar holidays and events can be permanently mapped to fixed ISO dates that will be the same every year.  Having said that, I am unaware of any list that maps holidays and events to ISO dates -- can anybody point me in the direction of such a list?  Has the ISO calendar entirely replaced the Gregorian calendar in any country?

The ISO calendar has no months.  The date is expressed as the year number, the week number within the year, and the day number within that week.

My Symmetry454 and Symmetry010 calendar do have months, retaining the traditional month names and 7-day weekly cycle.

My freeware calendrical calculator Kalendis maps holidays and events to Sym454 and Sym010 dates.

• The month lengths are 28+35+28 days = 4+5+4 weeks in the case of Sym454, or 30+31+30 days in the case of Sym010.
• For Sym454 every year, quarter, month, and week starts on Monday.
• For Sym010 every year, quarter, and week starts on Monday.
• They both employ a 293-year leap cycle having 52 symmetrically arranged and smoothly spread leap weeks per cycle:
• It is a leap year only if the remainder of ( 52 * Year + 146 ) / 293 is less than 52.
• The average leap week interval is exactly 294 weeks.

By the way, all of the above have the same epoch as the Gregorian calendar.

-- Dr. Irv Bromberg, University of Toronto, Canada

<http://www.sym454.org/>

[Irv Bromberg]

On 2012 Jan 1, at 15:44 , Irv Bromberg wrote:

The ISO calendar is a leap week perpetual calendar.  That leap week occurs once every 6 or 5 years, but due to its parallel relationship with the Gregorian calendar there is a 7-year interval once per 400 years (spanning the 300th year of each cycle).  This leap week is not going to "go away", and nobody will accept a null-day perpetual modification of the ISO calendar.

On 2012 Jan 2, at 13:01 , Sonny Pondrom wrote:

The problem with leap weeks is that they are confusing and hard to accept as measuring how the earth moves around the Sun every year.

Irv replies:  If a leap week would be so confusing and hard to accept (presumably because of its length), then how is it that the majority of the world's global population employs a traditional astronomical lunisolar calendar with a 30- or 29-day leap month?  (I am referring of course to the traditional oriental and south asian calendars.)  They seem to be not the least bit confused or concerned about the astronomical complexity of their calendar, nor does the one month leap that occurs every 3 or 2 years seem to bother them at all.

Given the approximately 30-day lag between the astronomical seasons and the weather seasons, and the chaotic variability of weather patterns, the relationship between Earth's orbital motion and environmental conditions is only approximate.  Thus the "man on the street" will not particularly notice the medium-term "equinox wobble" of a leap week calendar.  Have you tried asking members of the general public to define an equinox or solstice?  They are essentially clueless.  A few will say that the spring equinox is on March 21st (no longer true), but they won't know how to reckon an equinox moment or even the day of the equinox. Uncommon exceptions are places where there are intentionally positioned structures oriented in an east-west manner, which Sun will illuminate in a well-known manner near sunrise or sunset on the day of an equinox, or where a sundial is available.

Have you tried asking members of the general public to define the Gregorian leap rule?  Many will say they don't know.  Some will say that every 4th year is leap, and a lesser number will say it is a leap year if the year number is divisible by 4.  A few believe that it is every 5th year!  Hardly any members of the public know about the centurial year exceptions.

Have you tried asking members of the general public whether Earth goes around Sun or is it that Sun goes around Earth?  Although the majority will tell you that Earth goes around Sun, a very significant fraction, if your sampling is non-biased, will insist that Sun goes around Earth.  Polls conducted by Gallup in the 1990s found that 16% of Germans, 18% of Americans and 19% of Britons hold that Sun revolves around Earth. A study done in 2005 by Dr. Jon D. Miller of Northwestern University found that one adult American in five (about 20%) thinks that Sun revolves around Earth.

I'm just saying that any calendar reform proposal should seek to arrive at a design that is optimal.  Some people may object to the optimal design, but their objections will nearly always be ill-considered.  On the other hand the religious objections to a calendar that includes null weekdays will be fervent, determined opposition that there is no getting past.  If nevertheless some authority pushes through a calendar reform that breaks the traditional 7-day weekly cycle then it is only a matter of time until religious objection overturns it, as happened in France.

If the ISO leap rule is employed then there is no effect whatsoever on the Easter date -- it would be on the same actual Sunday as would be observed on the Gregorian calendar, so there is no basis for church opposition to a leap week calendar reform.

The statement below says that "nobody will accept a null-day modified calendar", but I think this has already been shown to be wrong.

Irv replies:  You misquoted me.  I wrote, quoted above, that nobody will accept a null-day perpetual modification of the ISO calendar.  If you want to go ahead and nevertheless continue to waste your time proposing a wide variety of null-day perpetual calendars then go ahead, but the ISO calendar is a recent calendar standard that is essentially set in stone.

Sonny continued:  In the past, The World Calendar (TWC) has been accepted by many nations and groups.

No, almost all nations and groups that "accepted" TWC did so on the condition that the USA also approve adopting TWC, or the decision was made by a dictator.  When the USA vetoed it in 1955, all support evaporated, and then Elisabeth Achelis dissolved the original TWC Association in 1956.  The still-existing current organization is a later reincarnation by a relative, later passed on to a friend.

-- Dr. Irv Bromberg, University of Toronto, Canada

<http://www.sym454.org/>

[Karl Palmen]

Some parts of this message have been removed. Learn more about Nabble's security policy.

Dear Calendar People

 

I believe Irv is referring to the calendar of the ISO Week Date

http://en.wikipedia.org/wiki/ISO_week_date

Note that the ISO standard is not confined to defining week numbers, but also day numbers and the latter do not form a perpetual calendar. Therefore the statement the ISO Calendar is a leap week perpetual calendar is not really meaningful and correct. Instead the ISO Week Date Calendar is a leap week perpetual calendar.

 

Easter can occur on any of six Sundays in this calendar, but can occur only on the 6^th of these six Sundays in a Gregorian leap year beginning on a Thursday with Easter on the latest possible date of April 25.

So with this exception Easter occurs on one of five Sundays in this calendar.

 

Interestingly, if the leap week year were postponed a week each Gregorian leap year beginning on Thursday, not only would Easter occur only on five Sundays, but also 44 Gregorian dates would occur on the same week every year, rather than 8 with the ISO week date calendar.  This modified ISO week date calendar could be defined so that week 9 always has March 1^st .

 

Karl

 

12(07(10

 

2012 Week 1 Day 2

 

From: East Carolina University Calendar discussion List [mailto:CALNDR-L@...] On Behalf Of Sonny Pondrom
Sent: 02 January 2012 03:55
To: CALNDR-L@...
Subject: Re: Perpetual calendar for the world

 

What calendar are you referring to - ISO-8601?

 

Sonny Pondrom

sonny@...

2012-Q1-W01-D1

"Happy New Year"

 

 

On Jan 1, 2012, at 2:44 PM, Irv Bromberg wrote:

 The ISO calendar is a leap week perpetual calendar.

 

--
Scanned by iCritical.

[Irv Bromberg]

On 2012 Jan 3, at 09:00 , Sonny Pondrom wrote:

If the 454 calendar was adopted, like many others that start on Monday, all that wordage about Thursday could be eliminated.

I have no idea what Sonny means by the above sentence.

The Thursday rule is used for the ISO calendar, it has nothing to do with the Sym454 or Sym010 calendars.

The months in a quarter could be easily identified by weeks 1-4, 5-9 and 10-13.

That is the 4+5+4 pattern, but what is your point?

And if the non-week days are placed at the end of the year, then ordinal days 365 and 366 will fall nicely in the 13th week of the last quarter.

What the <beep> is a "non-week" day?  There are no days in the ISO or Symmetry calendars that are outside of the traditional  7-day week.

For a leap week calendar, days 365 and 366 have no particular significance.

-- Dr. Irv Bromberg, University of Toronto, Canada

<http://www.sym454.org/>

[Irv Bromberg]

On 2012 Jan 3, at 08:09 , Karl Palmen wrote:

Easter can occur on any of six Sundays in this calendar, but can occur only on the 6^th of these six Sundays in a Gregorian leap year beginning on a Thursday with Easter on the latest possible date of April 25.

So with this exception Easter occurs on one of five Sundays in this calendar.

 

Interestingly, if the leap week year were postponed a week each Gregorian leap year beginning on Thursday, not only would Easter occur only on five Sundays, but also 44 Gregorian dates would occur on the same week every year, rather than 8 with the ISO week date calendar.  This modified ISO week date calendar could be defined so that week 9 always has March 1^st .

Easter and related days counting down to and up from Easter would be observed on the same actual day as the Gregorian calendar.

ISO date YYYY-W14-7 ought to be the median date for Gregorian Easter on the ISO calendar.  If so then it could be proposed as a fixed date for Easter.

Events that regularly occur on the nth day of a Gregorian month have an undefined observation date on the ISO calendar, which if permanently assigned would differ from the actual Gregorian day in most years.

Events that regularly occur on the nth k-day of a Gregorian month could be assigned to that k-day in a specific week of the ISO calendar, but would such events always be observed on the same actual day as the Gregorian event?

-- Dr. Irv Bromberg, University of Toronto, Canada

<http://www.sym454.org/>

[Irv Bromberg]

On 2012 Jan 3, at 12:35 , Sonny Pondrom wrote:

On 2012 Jan 3, at 09:00 , Sonny Pondrom wrote:

If the 454 calendar was adopted, like many others that start on Monday, all that wordage about Thursday could be eliminated.

Irv wrote:  I have no idea what Sonny means by the above sentence.

Sonny replied:  Karl already answered this one.

Irv replies:  I have no idea how Karl's answer relates to your sentence quoted above.

Irv wrote:  The Thursday rule is used for the ISO calendar, it has nothing to do with the Sym454 or Sym010 calendars.

Sonny replied  Yes, the Thursday rule was an attempt to make the calendar useful for commerce.

Irv replies:  No the Thursday rule is a simple statement of the rule for selecting which Monday an ISO year starts on.

Sonny continued:  But its complexity trumped the goal.  Businesses were looking for a simple rule to start the year on Mondays.  The use of Week 53 and Week 1 was considered risky when years do not start on Monday.

Seems like a simple enough rule to me.  What is "risky" about week 53 or week 1?  They are just dates like any other dates.

By the way, how do you know what the date is?

Do you perform Gregorian calendrical calculations in your head, or on paper, or using a calculator or a spreadsheet?  I'll bet you don't.

Do you simply look at your watch?  Your cellphone?  Your pager?  Your computer screen?  I'll bet you do.

When a reformed calendar is adopted you will use the same methods to reckon the date without calculations.

The details of the calendrical arithmetic are irrelevant to the user.

They are only needed by those who are implementing such a device, and after the implementation is complete they no longer care about those details.

Sonny wrote:  The months in a quarter could be easily identified by weeks 1-4, 5-9 and 10-13.

Irv replied:  That is the 4+5+4 pattern, but what is your point?

Sonny replied:  My point is that if I know its the 3rd quarter and you reference Week 7 Day 3, then your date is Wednesday, August 17.  Another example for the 2nd quarter Week 9 Day 5 would be;  Friday, February 33.

Irv replies:  I still don't get Sonny's point.  If you want to use an ISO calendar, or a year-week-day calendar format then go ahead.  I don't see why anybody would seriously entertain using a year-week-day calendar that was not the ISO calendar.  Like I wrote repeatedly before, the primary reason to propose reform of the Gregorian calendar is to make it perpetual, without that there is no point in proposing other tweaks to the calendar, but with a perpetual reform we may as well make everything optimal while we're at it.  The ISO calendar is already a perpetual calendar, so there is no point in proposing any tweaks to it.  It suffices as is, for those who are willing to give up the traditional 12-annual months date format.

Sonny wrote:  And if the non-week days are placed at the end of the year, then ordinal days 365 and 366 will fall nicely in the 13th week of the last quarter.

Irv asked:  What the <beep> is a "non-week" day?  

Sonny wrote:  You know.   Those blank days that will make the ISO Week Date calendar more useful.  

Irv replied:  There are no days in the ISO or Symmetry calendars that are outside of the traditional  7-day week. For a leap week calendar, days 365 and 366 have no particular significance.

Sonny replied:  This is True for you, but False others who use the ISO Week Date calendar.  This is the calendar for people who would like to co-exist with those plagued with irregular months using traditional 7-day weeks,  These ordinal days are significant.  They are the days of the year that could be used in a perpetual ISO Week Date calendar.

Irv replies:  Sonny get this straight.  The ISO calendar is a widely used perpetual calendar, without any pesky null days.  Having gone to all the trouble of avoiding null days, obviously there is no way that the ISO will consider putting null days into the calendar.  If you want to have your own year-week-day calendar that has a null day or two at the end of the year then go ahead, but you won't succeed in getting anybody else to follow you.

Sonny continued:  Please don't act like the US law makers, who are turning down changes that will help the country, because they are afraid that they will not get credit for any  improvements.   If the 364 days of the Sym454 gets approved, you will certainly get the credit for picking the majority of the days.

Irv replies:  I don't understand Sonny's strange comments.  The international arena has already got very close to picking two perpetual calendars having null days.  The Thirteen-Month calendar was considered and ultimately rejected by the League of Nations, and The World Calendar was considered and ultimately rejected by the United Nations.  Does this tell you something?  What is your thinking process?  Do you think that I personally had anything to do with those reform rejections?  I was just a newborn when the UN rejected TWC.  Do you really want to keep banging your head against the wall?  Do you seriously think that it worthwhile yet again to propose a null-day perpetual calendar in the international forum, hoping to "sneak it through when the religious people aren't looking"?  Are you deluding yourself into believing that people are getting less religious these days, so although it was rejected in the past, it has a chance of being accepted today?  Are you just thinking "Well I don't care about religion so screw the religious people, I want the calendar that I want, and that's it!"

On 2012 Jan 3, at 08:42 , Sonny Pondrom wrote:

All kidding aside, the 454 calendar is pretty good.  The problems are:

(1) Multi-year contracts may include years with more than one day of different lengths.

Irv replied:  I have no idea what Sonny meant by point (1).

Sonny replied:  Can you imagine a contract that would give one side or the other an extra week of work or goods on leap years? 

Irv replies:  The worst case is a single-year contract that could span 52 or 53 weeks.  A mild case is a multi-year contract that may have an extra leap week if the span includes or not.  This could be a long term contract that includes 3 leap weeks when started in a certain year, or 4 leap weeks if started in a different year.  Obviously the longer the duration of the contract, the less significant the extra leap week becomes.

So there are several possibilities.

1)  Both parties could agree on the duration, without a pro-rated price adjustment.  Generally this would be slightly disadvantageous to the vendor, but on the other hand it may help seal the deal.

2)  The contract can span a fixed number of weeks, perhaps a multiple of 52, no adjustment required.

3)  Both parties could agree on the duration, with a pro-rated price adjustment for the extra leap week.

4)  Annual or longer contracts could be drawn up on the basis of 52-week years in all cases, with each spanned leap week accounted for by a pro-rated adjustment.

Again I cite the case of the widely used oriental lunisolar calendars.  Can you imagine contracts for those?  A contract spanning several years may differ by 30 days in length depending on when the contract starts.  Also, although a computer system can project the future date for fulfilling the contract, the actual calendar is controlled by the central authority, and they may use different astronomical algorithms or a different delta T, or the actual delta T may differ from what was projected, causing the leap month to move or be postponed to the next year.  Thus the oriental calendar dates are unpredictable, and this uncertainty has to be accepted in contracts written according to those calendars.

There is nothing uncertain about using a fixed arithmetic leap week calendar for contractual purposes, whether it is the ISO or Sym454 or Sym010 calendar, the arithmetic is all straightforward.  It comes down to just the bottom line:  Do you want to do business, or not?  For businesses advantages of a perpetual calendar are very compelling, and today the vast majority of businesses have computer systems tracking their transactions, so they are not the least bit concerned about minor arithmetic considerations in regard to their contract dates.

Sonny wrote:  (2) Calculating leap years without a calculator is more difficult than the current rule.

Irv replied:  I previously explained that there is no need to calculate leap years.

Sonny replied:  I  hope we are not boring others about this.  All though the current calendars do not need to calculate leap years, if they are not simply spread evenly over centuries, there is a need.  This need for leap weeks must be satisfied by calendar creators.  

Irv replies:  I don't understand at all what you meant.  I have told you that for calendrical arithmetic involving the Sym454 or Sym010 calendars there is no reference to the leap rule.  It flatly isn't involved in the calendar arithmetic.  Not now, not ever.  For any number of millennia, the leap rule doesn't matter in the calendrical calculations.  And I've told you that is so because the leap week is at the end of the year.  If you don't understand this, and yet refuse to read my explanation of this issue in my on-line documentation, then I've got nothing further to say about it.  If you refuse to learn then what can I do?  [You might be willing to endlessly bang your head against the wall, I'm not.]

Irv wrote:  A short list suffices for a lifetime, and the leap rule is not used in calendrical calculations.

Sonny replied:  A short list means the perpetual calendar must be replaced.  The primary goal of a new calendar is to be perpetual and not waste time and materials.  

Like today's ISO calendars, the perpetual calendar does not need a list of year on the front or back.  

Irv replies:  Fine, you want it to be a longer list?  52 year numbers covers a full 293-year cycle, is that long enough to satisfy you?

How about a single-page list that spans multiple millennia, is that long enough to satisfy you?  It is openly posted on-line at:

http://individual.utoronto.ca/kalendis/leap/52-293_sym454_leap_years.htm

or

http://individual.utoronto.ca/kalendis/leap/52-293_sym010_leap_years.htm

(those web pages are identical except for the title)

I don't understand at all what you meant by "like today's ISO calendars".  Are you somehow believing that there isn't a similar list of leap years for the ISO calendar?

The ISO leap years for a few millennia are posted here:

http://individual.utoronto.ca/kalendis/leap/ISO_sym_leap_years.htm

(That report title says "ISO Symmetry454" but you can ignore the "Symmetry454" in the title, as it was calculated using the ISO leap rule and those are truly the leap years of the ISO calendar.  Note that there is a 7-year interval once per 400 years.)

People are going to want printed copies of calendars so that they can make notations on them, and they will continue to replace their calendars each year.

The goal of a perpetual calendar is to take advantage of the opportunity to avoid rescheduling recurring events where possible.

Sonny wrote: I'm sure that some day they will appreciate us making the ISO-8601 calendar perpetual.

Irv replies:  The ISO-8601 calendar is already perpetual, always has been, and it has no pesky null days.  What are you not understanding about this issue?

Sonny wrote: adding those blank days is the easiest way to fix the ISO-8601 calendar. 

Irv replies:  The ISO-8601 calendar doesn't need fixing, there is nothing wrong with it (at least nothing of significance, assuming that the loss of the 12 monthly divisions is acceptable).  It achieves its goals and is widely used.  It represents an excellent transition calendar from the Gregorian leap day to the ISO leap week style.  I think that the ISO calendar would be more widely used, and may replace the Gregorian calendar entirely, if the handling of holidays and events were specified.  This is because without those specifications people will continue to need a month-oriented calendar to know when those holidays and events will occur.  This seems to be a non-issue for international banking and industry because those are essentially non-stop businesses, 24h/day 7d/week.  They just use the calendar to coordinate their activities.

Sonny wrote:  Best regards and I'm sorry you feel so strong about keeping 7 day consecutive.   

Irv replies:  My feelings on this issue are irrelevant, and you don't know what they are.  I'm just advising you not to continue banging your head against the wall because the null weekday idea has already been summarily rejected twice in the international arena, and it will never fly.

Irv wrote:  Are you talking about an original birthday that actually occurred within a leap week?

Yes, not the straw man that you keep knocking down.

Irv replies:  I have no idea what Sonny means by that comment.

Irv wrote:  The probability of that occurring is 1/294.   

Sonny replied:  and the probability of a birthday is 1/1.

Irv replies:  You are dead wrong.  For the case of the 293-year leap cycle, globally the long-term probability of any individual baby being born during a leap week is exactly 1/294.  If you are talking about a certain person who was born during the leap week then probabilities are irrelevant.  Retrospectively, once the facts are known, there are no uncertainties, no probabilities.

The probability of a person being born on Gregorian Feb 29th is 97/146097.

and the probability of a person being born on the last day every four years is 1/4.

Irv replies:  Again you are dead wrong.  The probability is as I stated, which by the way is much lower than your 1/4 fraction.

The rule is no different than it would be for a leap day calendar.

I beg to differ.  Seven times more people will be born during a leap week than a leap day.  If the rule does not change then there will be 7 times more people  switching their birthday to either December 28 or January 1.    WOW! That contest for the first born baby in the new year has gotten complicated.

Irv replies:  Yet again you are dead wrong.  The ratio is exactly 1/294 : 97/146097 = 5+167/1358, so only a tad greater than 5 more people will be born during a leap week than during a leap day.  And I also outlined the rule that from the end of the year a birthday (or other event) can't shift to the next calendar year, because that would cause two birthdays to be observed during that next year if the next year is a leap year.  The simple rule for a leap week birthday is as I stated before:  "It is always on the same weekday in the last week of the year."

-- Dr. Irv Bromberg, University of Toronto, Canada

<http://www.sym454.org/>