About a «world» calendar

What is a Calendar?

Every system of calculation which divides time into days, months, years in accordance to the constant, periodic phenomena of the Earth spin round its axis, the Earth revolution round the Sun and the Moon revolution round the Earth, to achieve an organization in public and religious life and to serve different scientific and historical needs. There are lunar/solar/ancient greek/ chinese/ arabic calendars.

Therefore, every calendar is an instrument which classifies past or future events. But, first and foremost, it is a study of the sky(ουρανός->ouranio). The solar, earth and lunar motions are eternal, fixed reference points for the earthly time sense.

Gregorian calendar

The Gregorian calendar should be called: Gregorian correction of the Julian calendar. It is, in its entirety, the Julian calendar corrected through one day for each century. Specifically, it restores to 365 days every first year of a century (e.g. 1900 – but not 2000) which was initially a leap year (366 days) in accordance to the general rule: Every year divisible by 4 is a leap year

When Julius Ceasar imposed his calendar (46 B.C.), the old Roman calendar had major discrepancies from real astronomical data, producing malfunctions in agriculture and social life. The ancient Greek calendars (all lunisolar) had solved the calculational problems to which the (more ancient and lunisolar too) roman one was exposed.(2) Nevertheless, despite the efforts of Sosigenis, which was Greek and possibly was ordered by Julius to create the calendar, the new system of time calculation was only solar. It had enough exactness for this historical period, but it was, by definition, seperated from the lunar factor which caused a need for complex calculations and increased therefore the need of mathematical edition (a prime function of priests in old times, cf. Egypt, Babylon).

It could be said that the roman High Priest (pontifex maximus) Julius Ceasar solved the calendar problem with the lunar factor in the same way Alexander the Great  solved the Gordian Knot:

He cut it in two!

It could also be said (not so flattering for Ceasar) that he did as described in the greek proverb: If the head aches, you should cut it…

The Julian calendar is, in reality, enough for the arrangement of most social occurances which presuppose an exact calendar: debts, office succesions, pays etc.

It insures succesfully the proper function of agriculture, for which year seasons play a major role, by defining correctly the year solar circle,  namely forecasting exactly solstices and equinoxes. 


  • Are the forementioned needs the only ones which should be taken into consideration by a calendar?
  • If these needs are served in a minimum grade, is it enough?
  • What does the lunar absence from the western culture represent?
  • Is «simplicity»/simplification the real question in (modern) civilization?
  • What does the calendar of every civilization represent? Which are the differences and the similarities between the calendars throughout the centuries?
  • Do people create the calendars or do they follow them?

Our approach

Our project follows a series of questions similar to the aforementioned and poses also new ones.

We started having as instrument a dynamical environment, common and accepted from all, but also capable to measure time according to the place of everyboy on Earth and his personal way (cf. About home page), looking forward to present calendars of the various civilizations or, at least, the most predominant.

The effort is based on three «cornerstones» and (for the start) to the, so called, Gregorian calendar which is today accepted by the whole world (or a great part of it)…

Day, Synodic month, Year. Main time cycles on Earth
Day, Synodic lunar month, year, three circles of earthly time

1st cornerstone, the Cycle.

Universal symbol of Time, illustration of the spherical nature of celestial bodies, the Perfect Plane Figure; it implies an unseen center and, most importantly, visualizes the cyclic nature of Time.(2)

(Ιncidentally, we must refer to a full helix of Earth round the Sun and not to a full planar revolution, because the Sun moves in the Galaxy.)

2nd cornerstone, the coexistence of Sun and Moon in the calendar.

An expression of the cosmic harmony of opposites (enantiodromy – enantios=opposite, dromos=road, way), of the Giver of Life, the Sun, and the Protector, the Moon.

Projection of the lesser known real motion of the Moon in space which renders directly comprehensible the notions of synodic and sidereal lunar month, restoring the Moon as key factor for life presence on Earth.

3rd cornerstone, the Human Being.

Every peoples’ calendar can be Solar, Lunar or Lunisolar. The times of sunrise, sunset, moonrise, moonset differentiate on Earth’s sphere. But the sky, above our heads, remains the same. Differentiality is not opposed to unity. 

Likewise, the calendar can refer also to the personal time – the daily time, personal existence and evolution, introduced in a natural frame of reference  the only undeniable: the stellar motions.

Quotations from the world tradition and the wealth of human Logos (the greek analog of ratio, but still a much wider notion) complete the composition as an inseperable and discrete part of the whole: short phrases, quotes, proverbs from all over the world and languages. They decorate our work and your days. The collection is a discrete project which is combined with the entirety – like a 4th dimension to the treedimensional calendar! 

Conclusion – The necessity of all these

We know that the study of sky is a source of wisdom and the calendar can function as a «window» to the sky and the World.

We understand that the calendar is not a separate creation of every civilization, but a two-way frame for its evolution – a bridge to the other civilizations.

We understand the oikoumenical thought (the essential part of «globalization») as a necessary reality and we want to discover whatever unites Humanity.

We believe that calendar can provoke a daily connection of the user with the Sky, the World, the Beauty, the Rhythm and the manifestation of Life itself, as well as remind daily our true nature: the cosmic one – transient and eternal at the same time. 

  1. The «cyclic» time is eternal and unborn in contrast to the «linear» one which has a Beginning and an End. (See also: About the concept of Time)
  2. Meton of Athens discovered the Metonic cycle in 5th century B.C. Νamely that 19 solar years correspond to 235 synodic lunar months.