I’ve always been fascinated by calendrical systems, as it has always been basically the only way we as a civilization know how to track time. Just some of the forms that have come about over the ages:
- Weekly, monthly, and yearly calendars
- The different phases of the Moon, the Sun, and the four seasons
- The changes in the paths of the stars in the sky
As you might have noticed, there is a variety of different systems. However, as far as I know, there is no system that can specifically classify these systems.
So, I thought I’d give it a go, which is what you’ll find below: the CIC Cataloguing System, or CICCS.
A = Calendar Type Identifier
B = Calendar Subtype Identifier
C1 = 1st-Level Number Base
C2 = 2nd-Level Number Base
C3 = 3rd-Level Number Base
C𝑛 = 𝑛th Number Base
Calendar Subtype Identifier: A 4-letter abbreviation for a particular calendar type.
- GREG for the Gregorian Calendar
- JULN for the Julian Calendar
- MAYA for the Mayan Calendar1
- FREV for the French Republican Calendar
Calendar Subtype Identifier: A 3–10-character abbreviation for a particular variation of a calendar type. Fewer characters are better, but sometimes brevity must be sacrified for conciseness, as one will see in the first of the examples below.
(This element is optional, since not all subtypes are always known or no subtypes exist.)
- ISO8601 for the ISO 8601 subtype2 of the Gregorian Calendar
- DSR for the Daisho-Reki subtype3 of the Japanese Calendar
- IFC for the International Fixed Calendar subtype of the Gregorian Calendar
- TIC for the Tabular Islamic Calendar subtype4 of the Islamic Calendar
2nd-Level Base: The numerical base of all next-larger units that are multiples of the 1st-Level unit(s).
3rd-Level Base: The numerical base of all next-larger units that are multiples of the 2nd-Level unit(s).
𝑛th-Level Base: Just another way of saying, “… and so on until calendar is sufficiently classified.”
Step-by-Step: ISO 8601
In the ISO 8601 form of the Gregorian Calendar, the 1st level consists of the Gregorian minute and the Gregorian hour, both of which are directly subsequent to the SI second in terms of magnitude. Thus, this latter unit is the base unit, the former units being 60× its value.
The 2nd level is the solar day, which is base-24 due to being a multiple of the 1st-level unit, the Gregorian hour.
The 3rd level is the solar year—its base is 365, due to it being a multiple of the 2nd-level unit, the solar day.
(Note: You could place the Gregorian month as the 3rd-level unit and the solar year as the 4th-level unit, but you would have to place a variation operator, i.e. plus-or-minus ( ± ), since a Gregorian month’s length is not constant. Defining the year’s base in days makes it more organized and is just as much, if not more, frequently used in day-to-day life.)
Therefore, ISO 8601’s profile would be as follows:
Calendar Subtype: ISO 8601 (ISO8601)
1st-Level Base: 60
2nd-Level Base: 24
3rd-Level Base: 365
Calendar Identification Code: GREG-ISO8601-60:24:365.
1 For more information on the Mayan Calendar, see this article by the Smithsonian National Museum of the American Indian.
2 Courtesy of Dr. Markus Kuhn, a University Senior Lecturer at the University of Cambridge, released under a CC BY 4.0 International license.
3 For more information on the Daisho-Reki subtype, see this article by the National Diet Library of Japan.
4 Courtesy of Utrecht University.