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There are 12 hours in a day for the same reason 13 has a tradition of being an unlucky number. The Babylonians (and Sumerians?) used a base 60 numbering system. They attributed mystical significance to numbers. Good and powerful numbers divided 60 evenly. 7 is the first number that doesn't divide 60 evenly and, curiously, got tagged as "lucky". 8 was considered the weakest of the numbers from 1 to 12. 13 does not divide 60 evenly and so was thought a "bad" number. When anything important needed dividing into units, such as the hours in a day, it was done in some even divisor of 60 with 12 being the most popular. That the moon happens to wax and wane approximately 12 times a year and that a year is close to 60*6 = 360 days only reinforced the holiness of base 60 numbering. To prevent the 360 day calendar from getting out of sync, the 5 extra days in a year were used for a holiday which was called Saturnalia. (Think Saturnalia must be a Roman name, after Saturn which in the Greek mythos is Chronos, God of Time.)

Looks like all the entries on units of time are missing this history. Also the entry on Babylonia barely mentions this and the entry on Sumeria is totally silent.

This article is quoted from by Julian Palmore, Professor of Mathematics at the University of Illinois in the "Ask The Expert" column appearing in the May/June 2005 issue of Illinois Alumni, a newsletter for alumni of the University of Illinois. The first sentence is quoted. It would be useful to provide a reference(s) for this first sentence along with references supporting other information in the article. Courtland 13:26, 2005 May 12 (UTC)

Someone 2 fix plz

"The importance of 12 has been attributed to the number of lunar cycles in a year..." Um. Aren't there thirteen? I have to concur with the headline of this section. —Preceding unsigned comment added by 76.93.226.146 (talk) 21:27, 8 August 2008 (UTC)Reply[reply]

It is about 12.37 month per year. Thus, a year is usually considered to have 12 months "by default", with intercalary month added every two or three years to keep both in synch in Lunisolar calendar such as the Chinese calendar.--R. Vercetti 16:12, 6 December 2012 (UTC) — Preceding unsigned comment added by Reno vercetti (talk • contribs)

« In the modern 24-hour clock, counting the hours starts at midnight, and hours are numbered from 0 to 23. Noon is always close to 12:00 (differing according to the equation of time) » How far can it be? The largest departure would be when the equation of time has the steepest slope, and be accumulated over a mere 12 hours. Using the Equation of time approximation, it looks like at most 14 s. The sentence remains unclear. Urhixidur 15:54, 2005 August 22 (UTC)

The hour was originally defined in Egypt as 1/24 of a day, based on their duo-decimal numbering system (which counted finger joints on each hand).

The Egyptians used a base-10 numbering system. The relationship between this, 1/24 of a day, and finger joints isn't obvious… I'm happy to edit the article if someone can explain the relationship to me. Barefootguru 23:52, 12 September 2005 (UTC)Reply[reply]

a duodecimal numbering system (counting with each thumb the spaces between the joints of the other finger on the same hand, i.e. 3 x 4 = 12)

This is rather confusing. What exactly does it mean? -213.122.110.231 15:31, 8 May 2006 (UTC)Reply[reply]

I can't believe that "civilizations" was misspelled. Please be more careful when editing articles. —The preceding unsigned comment was added by Coolbho3000 (talk • contribs) 00:06, 1 June 2006 (UTC)

What does this mean?

" (counting with each thumb the spaces between the joints of the other finger on the same hand, i.e. 3 x 4 = 12) "

Scrutchfield 22:03, 11 June 2006 (UTC)Reply[reply]

Degrees minutes and seconds are derived from satanic origin, because there are five sixes at five ends of satanic pentagram, thus gives 6*5=30 minutes, thus half of degree. Additionally 60 minutes, 60 seconds, 60 tierces are multiples of 6. Thus much better solution would be using septenary or at least decimal units for measuring time and angle. Sexagesimal means six times ten, where six is taken from number of the beast. Here is God-derived alternative to these satanic units: http://the-light.com/cal/veseptimal.html that has nothing to do with babylonian satanic measurements. More about full septimalization of all units here: [1]

Comprehensive proof of evilness of these unholy numbers such as 6,60,90,180,270,360,666,3600,6666, which refuses to be completed up to multiples of holy seven is placed here: [2] 83.19.52.107 09:52, 15 March 2007 (UTC)Reply[reply]

It would be nice if you would qualify all statemntes with the warranted IMHO, ITHO, etc. With Post-Hollyween Greatings, Jclerman 19:35, 1 November 2007 (UTC)Reply[reply]

I don't know what is imho or itho, thus I will leave this out. 83.5.23.78 20:02, 1 November 2007 (UTC)Reply[reply]

Better yet: Keep such unscientific and historically incorrect drivel out of WP entirely.94.220.254.157 (talk) 02:24, 5 March 2010 (UTC)Reply[reply]

Will the article cover the various abbreviations and also the dimensional symbols that have been used and are preferred by various organizations? Joefaust (talk) 23:21, 1 June 2010 (UTC)Reply[reply]

In so-called Italian time, or "Italian hours", the first hour started with the Angelus at sunset (or the end of dusk, i.e., half an hour after sunset, depending on local custom and geographical latitude). The hours were numbered from 1 to 24.

I think there may be some confusion here.

The Angelus bell can refer to sunsrise, noon and sunset.

In Roman times the Primus horus - the first hour - began at sunrise. Days were divided into 24 hours, 12 of day and 12 of night (the hours were of variable length as the seasons changed).

Had the Romans invented the clock then what showed on them as One am would have been our 7 o'clock in the morning.

I suspect that the early clocks referred to as showing 'Italian Time' were actualy using the old Roman system of counting the hours from sunrise not sunset as suggested.

The footnote referring to a clock striking six at midnight would still make equal sense.

What is odd and unexplained is that at some point several hundred years ago we began counting the start of each day from midnight rather than sunrise and began referring to the time as O'clock ('Of the clock') - presumably to distiguish clock time from 'normal' time. When? Why? Who?

More research needed. —Preceding unsigned comment added by 92.12.50.21 (talk) 12:12, 28 June 2010 (UTC)Reply[reply]

This section needs to be rewritten. It improperly conflates unequal or temporal hours, reckoned from dawn, with Babylonian hours, which are equal hours reckoned from dawn. A convenient (if not ideal) source is this discussion of sundials. It also answers the above query about Italian hours. --SteveMcCluskey (talk) 21:09, 6 December 2012 (UTC)Reply[reply]

The Anglo-Norman term was a borrowing of Old French ure, a variant of ore, which derived from Latin hōra and Greek hṓrā (ὥρα).

no source for the above, when the fact is that Er is Indo-European, which would have influenced both Latin and Greek. Meanwhile, we have Old Norse Urðr, “The Past,” not to mention what became modern High German's Uhr. Does that lead to a conclusion - unsourced - that the Anglo-Norman term is a "Borrowing" of the Old French term? — Preceding unsigned comment added by 207.255.64.121 (talk) 03:20, 10 May 2021 (UTC)Reply[reply]

The following Wikimedia Commons file used on this page or its Wikidata item has been nominated for deletion:

• International System of Units Logo.png

Participate in the deletion discussion at the nomination page. —Community Tech bot (talk) 22:39, 7 January 2022 (UTC)Reply[reply]

The intro describes how the concept originates from the Ancient Near East but the body of the article doesn't mention it at all. Viciouspiggy (talk) 20:59, 15 January 2024 (UTC)Reply[reply]