Please add {{WikiProject banner shell}} to this page and add the quality rating to that template instead of this project banner. See WP:PIQA for details.
This article is within the scope of WikiProject Time, a collaborative effort to improve the coverage of Time on Wikipedia. If you would like to participate, please visit the project page, where you can join the discussion and see a list of open tasks.TimeWikipedia:WikiProject TimeTemplate:WikiProject TimeTime articles
The section titled "Abbreviations" has no cites and I couldn't find any mention of the PD an MD in Albanian on a Yahoo! search other than Wikipedia and its forks and mirrors. Zginder00:46, 29 August 2007 (UTC)[reply]
Yeah, besides being cute (I'd love to call 8am "eight-pi-mu" and 3pm "three-mu-mu"), this section is redundant, unsourced, and completely unnecessary. I strongly suggest deletion. -- Tkgd2007 (talk) 22:34, 10 April 2008 (UTC)[reply]
"...one must fall back on one's cultural literacy to disambiguate". Besides not passing the laugh test, it is an overstatement of the situation. It is taking something rather elementary and making it appear difficult. JackOL31 (talk) 15:32, 1 January 2010 (UTC)[reply]
"The use of a.m. ... can be confusing because am is an English word, AM ...amplitude modulation and A.M. ... anno mundi, in the year of the world, and for Master of Arts". This is an example of excessive criticism. Context clues can not be ignored and we cannot frame this from the perspective of a clueless person. All abbreviations are typically used within a context where the meaning is clear. This article uses BC and AD, however I don't see any criticism that those might be confused with - British Columbia, Book Club, Birth Control, Boston College, Bar Code, Before Christmas, Bankruptcy Court, Board Certified, Birth Certificate and Birth Control -or- Assistant Director, Associate Director, Active Duty, Attention Deficit, Associate Degree, Air Defense, and Assistant Deputy. Also, the mention of the recommendation for a space between the time and a.m./p.m. is sufficient. There is no proof that it is widely ignored (and violated is too strong a word for a stylebook convention). Lastly, combined similar concepts into a single paragraph. JackOL31 (talk) 02:43, 5 January 2010 (UTC)[reply]
Introduction section
The sentence regarding the am/pm variations is redundant. The Abbreviation section addresses the topic in detail. I'll remove the redundant information. JackOL31 (talk) 18:08, 13 December 2009 (UTC)[reply]
There is a sentence which says that the indication of noon and midnight is disputed. I cannot find any verification for this statement. I see where there is confusion, especially where the 24-hr system is predominant, but never any documented dispute. For manufacturers of timepieces with an am/pm indication, I have consistently seen the 12 o'clock hour displayed as shown in the table. Could someone cite references documenting a dispute involving the correct designations for the 12 o'clock hour? JackOL31 (talk) 18:48, 13 December 2009 (UTC)[reply]
In the accompanying table you will see (with references) that the U.S. Government Printing Office defines noon as 12 a.m. and NIST as 12 p.m. Those together document the dispute. −Woodstone (talk) 19:19, 13 December 2009 (UTC)[reply]
Thanks, I already checked that. That is an old version and the errata has been corrected. The latest version, the 30th Ed, identifies it correctly. The Style Manual is not govt statutes or administrative code. It's just a writing guide. Other documentation would be req'd, especially in light of the revision. JackOL31 (talk) 19:26, 13 December 2009 (UTC)[reply]
I just double-checked. I see the 30th Ed (2008) indicates:
b. Clock time (see also Time):
4:30 p.m.; half past 4
10 o’clock or 10 p.m. (not 10 o’clock p.m.; 2 p.m. in the afternoon; 10:00 p.m.)
Hmmm, looks like all of your references to the time at midday and at midnight are out of kilter. I spent 32 years in the military and then another 12 in the aviation regulation business and I can tell you that 12 am is midday andd that 12 pm is midnight. Look at it this way: both noon and midnight last for an infinitesimal amount of time. right up to the instant of 12 am is still a morning time and then it trips over into the afternoon. Towards midnight the time is always pm until that picosecond after 12 pm when it becomes a morning time which is always the am.
To do it the other way is silly as a piece of logic. Twelve, midday, is not the start of the afternoon it is the end of the morning. So 12 am is the last instant of the morning, just as 12 pm is the last instant of the after-noon. To get it straight in your mind just think of what that word afternoon means. If you're finding it hard let me tell you that 12 am is noon and after that you have all of the pm (times) hours.
If you don't like my logic try calling your local weather service or aviation service provider, or even the FAA's FSDO representative anyt any major airport.
I'm seriously shocked that the USGPO now says that it is the wrong way about. My copy of of their Style Manual from 1963 has it the way I explain above for the reason I have said. Maybe the 30th Ed of 2008 was edited by someone who is misconceived too? Lin (talk) 05:19, 22 January 2010 (UTC)[reply]
Long discussions (now archived) and references have established that 12:00 a.m. is commonly meant to be midnight, so 12:01 a.m. is one minute later to match. You will see this usage on any computer set to 12-hour display. −Woodstone (talk) 09:47, 22 January 2010 (UTC)[reply]
The use of "undefined" is not the most appropriate term for the 12-hour cell since 24:00 does not exist in the 12-hour world. This article is from the 12-hour system perspective (left-handed) and right-handed time notation does not exist. As a general rule of thumb for table entries where a cell exists but no value applies to the situation, an entry of "Not applicable" is made. JackOL31 (talk) 01:43, 15 December 2009 (UTC)[reply]
This table does not compare general English words. It compares 1-to-1 clock values. The concept of 24:00 does not exist, not applicable to the 12-hr system. My edit is reasonable and valid. Please discuss if there is disagreement. JackOL31 (talk) 12:11, 15 December 2009 (UTC)[reply]
Midnight at the end of a day is certainly an existing time that is expressed in English language. Many opening hours or contract durations involve that time. Therefore "not applicable" is not a correct description. There is just not a simple unified short way of writing it.
The statement of usage of a.m./p.m. at 12 o'clock is only meaningful for digital clocks (not analog ones). Mentioning that specifically is useful information in view of the ambiguity.
However, here we are not talking about clocks per se, analog or otherwise. We are showing the 1-to-1 relationship between the two systems. The words are added for clarification, but midnight end of day does not exist in the 12-system. In conversation one can say specifically midnight end of day, but it does not translate into a value in the 12-hour system. Why do you not think people will understand "n/a", it is a common enough concept? (I do appreciate the dialog) JackOL31 (talk) 13:09, 15 December 2009 (UTC)[reply]
Just as an FYI, I have a analog mantel clock that stops chiming and striking after 9PM. It picks up again at 6AM. I have also seen analog wall clocks that have external AM/PM complications. One in particular has a circular complication above the 6 with a small hand that moves clockwise, the left side marked AM and the right side marked PM. JackOL31 (talk) 13:21, 15 December 2009 (UTC)[reply]
In my understanding "not applicable" implies that the mentioned time does not exist. In my view its expression is merely "undefined" in the 12-hour system. A subtle, but real difference. On your (or any) analog clock at precisely 12 o'clock you cannot determine if the marker is a.m. or p.m., since the indicator will be just on the boundary between them. You can still determine if it's midnight or noon, because there are two such boundaries. On a device that just flips between them even that is not clear at the very instant. −Woodstone (talk) 14:24, 15 December 2009 (UTC)[reply]
Yes, the time 24:00 does not exist in the 12-hour system. This is why you cannot put a value in the entry next to the 24:00 entry. It simply does not exist. It is not applicable to the 12-hour system, whether anyone personally believes in a timeframe of 24:00-ness or not. What is important is that the 12-hour system does not believe in (i.e. incorporate) this concept and offers nothing regarding it. Consider the situation where one is writing an article on the 12-hour clock and one has never heard of the 24-hour clock system. Would that person be putting an entry of 24:00 (or some equivalent) in the table? Would that person even write out that particular row? The challenge is to look at this from a "12-hour system" perspective and not through a "24-hour system" pair of glasses. This means one must avoid taking concepts from one system and projecting them into another. No matter how hard you try, the Roman numeral system will never have a 0!
Regarding your comment on the limitations of physical timepieces, I don't see how that plays a part in our discussion but I will comment. If a analog timepiece changes to 12:00, I know at that very same instant the AM/PM indicator has toggled to the other value. The marker moves clockwise, so if it's at the "12 o'clock position" (or 6 o'clock position) I know the time, even if it is on the border. Yes, there are limitations to analog clocks, negligible as they are. However, many of them have character and beauty, and are works of art. Digital clocks will always be functional, sterile and butt ugly. That's why tower clocks are analog (real towers). JackOL31 (talk) 01:59, 16 December 2009 (UTC)[reply]
The Introduction section states that there exists/existed a dispute between the US Govt Printing Office and the generally understood standard regarding how 12 o'clock is displayed with respect to AM/PM for "beginning of day" and "noon". A excerpt is cited from the US Govt Printing Office Style Guide (29th Ed) and compared to everywhere else you can find the 12-hr standard listed, including the US GPO Style Guide 30th Ed. First, the GPO Style Guide does not set policy, it guides one in producing standard looking documents. Secondly, it cannot be shown that it is anything more than an error in printing. Errors in printed content do not imply a larger meaning. There is no evidence that the GPO intended to dispute the generally understood AM/PM settings for the respective times. Also, in light of the revision which reverses the entries and does a 180 on the meaning, I recommend any discussion regarding a dispute or the 29th Ed contradiction (Confusion section) be removed in its entirety. The table entry should be updated to reflect the most recent 30th Ed and the values contained therein or be deleted. JackOL31 (talk) 16:42, 19 December 2009 (UTC)[reply]
Unfortunately, I feel I must add the following to my previous comments. When I bring up additions, corrections or deletions to content, I expect to make those contributions. I'm happy to discuss significant changes and hopefully come to an agreement, but I would not expect my recommendations to be acted upon by someone else. I am capable of implementing my own recommendations and I would expect that as common courtesy. JackOL31 (talk) 17:55, 19 December 2009 (UTC)[reply]
If this last paragraph was aimed at me, I apologize. After I read your previous comments, and reread the article, I had to agree with you. I must confess I was too lazy to first discuss the changes here and implemented them right in the page. −Woodstone (talk) 18:33, 19 December 2009 (UTC)[reply]
Well enough, it's a good reminder that none of this is so urgent that we can't discuss it first. Anyway, apology accepted and we'll move on. Since you have not commented on my post previous to the last, I am assuming you're thinking it over. If you agree with me, we'll let it sit for awhile to see if anyone else has any thoughts they'd like to share. Then, assuming no objections, I'll go ahead and make the necessary changes. If you don't agree, we can discuss it some more. JackOL31 (talk) 21:46, 19 December 2009 (UTC)[reply]
As per my entry of 2 weeks ago (see above, "The Introduction section states..."), I have deleted the reference to a dispute which was not shown. A Style Manual does not carry any weight regarding govt regulations or policies. The most obvious assumption is that this was clearly an error and not indicative of a dispute between the GPO (charged with maintaing publications) and NIST or any other time organization. The complete reversal of this entry in the next edition is more than not indicative of a correction rather than a power struggle within the GPO organization with a new victor emerging. If one is to claim that the GPO intentionally decided to interpret AM/PM differently than what is the generally accepted historical understanding, one needs more proof than a contradictory entry in a style guide. If this entry is to be taken as proof, then we must also conclude that it becomes p.m. at 12:15 in the afternoon and it becomes a.m. at 12:25 in the wee hours of the morning - since these are the only entries the GPO Style Guide makes with respect to the relationship in the 12-hour system.
12 a.m. (noon); 12:15 p.m. (15 minutes past noon)
12 p.m. (midnight); 12:25 a.m. (25 minutes past midnight)
Along the same lines, I have modified the table to reflect the current 30th Ed info from the US GPO Style Guide. To cite an older edition which has been corrected is improper. Once again, one must consider the most reasonable and plausible explanation in these situations. If an entry in a book is contradictory to common knowledge without explanation and then reversed to agree with common knowledge in the next updated edition, I believe one must first conclude a correction rather that a disagreement within the publishing organization. The most egregious claim was "Two separate official style documents of the United States government disagree on the correct usage." To me, it appears to be stated in that manner to avoid stating that it was the same style document, with the latter being the most current revision. JackOL31 (talk) 15:03, 1 January 2010 (UTC)[reply]
While trying to verify the statements of Lin above I stumbled on the following document from a very official organisation. It contains:
Career Opportunity, U.S. Department of Transportation, Federal Aviation Administration
Your application must have a status of "Submitted" before 12:00 AM (midnight) Central Time on the Close Date for it to be accepted.
Logically this can only mean that a submission at any time during Sept 30 will be rejected. A 12 AM midnight on a date is surely not after the noon of that day. However I am fairly sure they mean that any submission on Sept 30 is still valid. Furthermore it contradicts Lin's claim about aviation. −Woodstone (talk) 16:46, 22 January 2010 (UTC)[reply]
I grew up in Kenya and remember that on New Years eve we waited until 12 pm for the New Year to roll around. I remember being quite amazed to find that in the United States noon was now 12 pm instead of midnight. Metricmike (talk) 01:07, 6 September 2010 (UTC)[reply]
It appears that in the original 12 hour time "system" the anti meridiem and post meridiem refer to hours past the hour of noon (the meridiem), therefore 12 noon was neither am nor pm and midnight was both 12 hours anti meridiem and 12 hours post meridiem. Perhaps this is why there is so much confusion. No amount of official US Government documents will clear this up because other countries and other people have a different concept of am and pm. In Kenya the locals count the hours from sunrise to sunset only, if the sun rises at 06:00 that is zero hour, then noon is 6 o'clock and 4 pm is 10 o'clock. I believe this was the case in all ancient societies until the invention of the (church) clock which could run 24 hours a day. Metricmike (talk) 01:20, 6 September 2010 (UTC)[reply]
The table in the introduction section has an inconsistency. The 12-hour entry associated with the 24-hour entry of 24:00 reads - (end of day) '(shown as start of next day)'. This is not correct. The 12-hour system, as far as the nomenclature is concerned, has no equivalent to the 24-hour artificial construct of 24:00. It simply does not exist within the 12-hour system. I believe a more appropriate entry would be 'n/a' or 'not applicable'. When I look up the meaning of 'n/a' in wiki, I see the definition listed, in part, as - for not applicable or ..., used to indicate when information in a certain field on a table is not provided, either because it does not apply to a particular case in question or... . Isn't that the situation we have here? Note: I addressed this issue in more detail in my 16 December 2009 entry. JackOL31 (talk) 20:04, 8 September 2011 (UTC)[reply]
Don't you think it's better to leave it open here and discuss the controversy in the later paragraph. I agree that a millisecond after noon is displayed as 12:00 (:00.001) p.m. (indicator) on most clocks showing a 12-hour display. Dbfirs21:48, 17 March 2012 (UTC)[reply]
History and use
Modified the last paragraph to include the inner ring values of 00 & 24 for the 12. Improved some of the wording. Also deleted the redlink to Comparison of the 12-hour and 24-hour clocks, which was deleted in October. JackOL31 (talk) 01:52, 19 December 2009 (UTC)[reply]
In the "Use by country" subsection, I revised the wording to present a more NPoV. The use of the term "unambiguously" is not necessary. It is sufficent to indicate the alternative terms to a.m./p.m. where it is not used or known. JackOL31 (talk) 03:47, 5 January 2010 (UTC)[reply]
The above seemed like a small change, changing wording slightly for NPoV. Otherwise, I would have posted chg in discussion and asked for comment. Once change is made, please discuss if differing view. I don't expect my good faith edits to be backed out. Please discuss why a more neutral PoV is not the proper wording. 173.88.207.233 (talk) 05:24, 5 January 2010 (UTC)[reply]
Your anonymous modification made a correct reflection of reality rather inaccurate. Therefore I had no doubt reverting it on sight. Here the explanation:
In many ... countries the 12-hour clock is commonly used ...
sets the reader on the wrong footing; it may be used, but mostly in informal statements only
In some instances, the terms a.m. and p.m. are not used or known.
outside the English speaking countries they are almost never used and often unknown; circumlocution is the only way of disambiguation.
These points were very clearly stated before your change. I do not see any POV in all this. They are statements of fact, not opinion. −Woodstone (talk) 14:15, 5 January 2010 (UTC)[reply]
I always try to bear in mind that even anonymous contributors are allowed full privileges when updating. Unless there is vandalism or gross misinformation, there is nothing to lose by starting a discussion and reaching an understanding prior to reversing out someone else's time and effort.
On another note, I can agree with your revisions. I propose the following:
In many European countries and Western countries, the 12-hour clock is commonly used in informal speech with descriptive phrases such as in the morning, in the afternoon, in the evening, and at night.[citation needed] Outside of English speaking countries, the terms a.m. and p.m. are rarely used and often unknown.
Non-neutral wording does not necessarily imply opinion, statement tone and innuendo also play a part. Wikipedia calls it a disinterested tone, I think of it more as a matter-of-fact tone. The earlier changes move toward that tone and also improve the concept flow.
I don't believe I can agree with your circumlocution assertion. I lean more towards - say it once, say it precisely, and say it concisely. JackOL31 (talk) 04:11, 6 January 2010 (UTC)[reply]
Can accept proposed new wording. Circumlocution was meant to apply to expressing the abbreviation a.m. by a phrase like "in the morning". In non-English Europe that is practically the only way the 12 hour clock is disambiguated every time it is required. −Woodstone (talk) 04:34, 6 January 2010 (UTC)[reply]
Changes made with one small exception, used "seldom" in place of "rarely". Seldom seemed more appropriate. This info still needs a citation though. Regarding your last statement, I perceive things differently than you. One can say 6:30 p.m., 18:30, or 6:30 in the evening. There is no aspect of ambiguity requiring disambiguation. It is flat out unambiguous. The interesting aspect of the 12-hour system is that one could say, for example, "I look forward to seeing you tomorrow at 6:30" and 99 44/100% of the time the correct meaning is still understood. For the other 56/100% of the time, you simply don't abbreviate. I've been saying that since '93. (Eh, that would be 1993 - not 1893, but you already knew that!) JackOL31 (talk) 01:51, 7 January 2010 (UTC)[reply]
Features of the 12-hour clock
Made a couple of small improvements/corrections. Changed "which almost all have just 12 hours" to "most of which display only 12 hours". Also, modified the reference to chiming the hour to striking the hour. A clock may chime on the hour, typically 4 times, but it strikes the count of the hour. They are two separate concepts. A few Wiki articles have this wrong, but I will take that up on their respective discussion pages. Removed the overstatement "requiring an understanding of it". First, there is no need for anyone to understand it (other than the clock manufacturer) for a clock to strike three times at 3 o'clock. Secondly, these are the same people who use "in the morning", "in the afternoon", and "in the evening". If you're around a 12-hour striking clock, you're know enough to get by. There needs to be some evidence of people hearing striking clocks and having difficulty understanding them to suggest "a required understanding". Everything requires an understanding in one way or another. JackOL31 (talk) 04:18, 7 January 2010 (UTC)[reply]
Section: Criticism and practical problems
This article states that one of the problems with this convention is that "It is not immediately clear on an analogue clock whether a time is a.m. or p.m." Calling 6:00 p.m. "1800" won't solve this problem, either. (The only reason I noticed this is that I've been working on a 24-hour analogue clock. Everybody seems to like it so far except for little kids).
And one more thing: Is it really more complicated to implement in software and digital electronics? How much code does it take to convert 1300 to 0000 to pm? That's like saying it's more difficult to eat a 45 oz steak as opposed to a 40 oz steak. Technically, yea. But no one's gonna notice. —Preceding unsigned comment added by Antigrandiose (talk • contribs) 19:41, 31 March 2010 (UTC)[reply]
The use of twelve instead of zero
I recall that the use of 12 instead of 0 in clocks was attributed to the non-existence of the number 0 until the 10th century, though I can't seem to find a source to evidence this, does anyone here know more about this? —Preceding unsigned comment added by 115.64.132.151 (talk) 14:03, 10 August 2010 (UTC)[reply]
Is it exactly 24 hrs between midnight to midnight, every day of the year or does it vary and averages to 24 hrs ?
It just came to my mind. This may be vague, and may not be a question though, in the universal context is our 24 hrs a 24 hrs exactly the same everyday from midnight to midnight. or does it vary each day and averages to 24 hrs every year i.e on full revolution. Chandrakantpushkar (talk) 09:22, 21 September 2010 (UTC)[reply]
It depends on what you mean. In the sense of 12-hour clock every day is precisely 86400 seconds, except once in many months, when a leap second is added, and that day is 86401 seconds. However if you mean the time between the Sun being at its highest point on successive days, it varies quite a bit, somewhere in the order of plus or minus 20 seconds. Over months it adds up to plus or minus 15 minutes. See for a detailed explanation Equation of time. −Woodstone (talk) 16:15, 21 September 2010 (UTC)[reply]
POV
Original edit summary [1]
"It's been my experience traveling the globe that everyone uses the 24 hour system with the exception of the U.S. Look at the website for airlines in any country to see what time system is used."
As you can see "My experience" is POV (where's the citation?), and airlines typically ALWAYS use the 24 hour clock around the world, just as trains do, and other forms of public transport! That doesn't say anything about what people use on a day to day basis, or even other businesses apart from transportation. Strange how the edit was by "MetricMike" who "wish[es] the US would get on with the conversion to the much simpler and more rational System International". Obviously biased editing. 91.85.177.45 (talk) 07:01, 26 September 2010 (UTC)[reply]
Let me Enlighten You
It appears from this article as well as the 24 hour clock article, which I will cc this comment to, that most if not all editors on this subject have missed the concept of a clock completely. Though, it is understandable to me because I myself did not make this realization until recently.
It is quite amazing to see that the creators of this ancient time measurement system seemed to understand this deep fundamental concept and was never questioned. While now all these smart anonymous editors don't even sense the concept rushing past them due to their weak reasoning.
Now that I am done being rude caused by the confident yet wrong content of this article let me prove my worth, though I will warn you I am not good at transcribing my thoughts to natural language but I will try my best so please bare with me.
The first thing to understand is that there is no such thing as Time = zero. When Time = zero it means you are dead. It does not exist because time only exists to you because you are alive to perceive it. In other words, the moment in time is a function of your unitary perception of all the preceding time before that moment such that your unit of perception is to the power of e.
Heh, let me try and explain that again. T = f(x):=e^x
So when you born, that absolute infinitesimally tiny moment when you perceive life. That is one unit of time, as soon as you continue to live for another one of those units of time, that is now the second unit of time. http://en.wikipedia.org/wiki/E_(mathematical_constant)
see this article for help understanding what I mean. Time would be the Y in the graph. As soon as you first perceive life, when x=0 time is 1. This is why there is no year zero. This is why there is not time 0:00 on a 12 hour clock. This is why I think a 24 hour clock is strange. Having time go from 23:59 to 24:00 then to 0:00 then to 0:01 makes no sense unless you share 1 second between 24:00 and 0:00.
There is a comment somewhere that says it is ambiguous as to whether midnight is the start or end of the day, yeah, no shit. You tell me what it is! A day is not an isolated universe of time, it is part of a continuous fabric of time that has not start or end. The end of the day is the start of the next day, there is never a moment when Time = zero as soon as the big bang happened. Time was 1 if you think that there must be a fraction of a moment before that first 1 then whatever fraction you are imagining would be the unit of time so that would be 1. As soon as there is existence time has already been created and it increasing.
The present is an infinitely small moment of time that is imperceivable, as soon as you notice it, it has already passed. You exist physically in the present but your mind exists by watching time fly towards you and then past you into the past as it gets locked into the memory of the universe and irrevocably stamps it's impact on all future events.
This can be intuitively seen and understood by every person. We all know that each year of our childhood felt very long. And as you get older every year seems to go by so much faster! This concept shows up in pop culture with sayings from kids like, "Are we there yet?" and old people such as, "It was just like yesterday."
The reason this is is because say you live for 1 year. Then you live 1 more year. You just doubled your life! As far as you are concerned you just lived for forever! Twice! Which becomes the new forever. And as you become 50 once you live one more year that is no longer as large an amount of time. It is only 1/50th what it used to be.
So the reason 12:00 the one that happens during the daylight where you are. Is called 12:00 pm is because as soon as 11:59 ticks one unit to 12:00 there is units less than a second we cannot comprehend that have already begun counting up. Once they reach 1 second it becomes 12:01 pm which is clearly the afternoon. So since some people like to clarify 12:00 when it is sunny with 12:01pm and not just 12:00pm, just think it is really 12:00:00:00:00:00:00:01 the moment it flips from 11:59 am.
That is why there is no 0:00. And I would love to hear from some electronics engineer explain how a 24 hour clock can display both 24:00 and 0:00. I did not realize time did not exist for 1 second everyday. I just am not sure if that second is at the 24th hour or the zeroth hour. Heh, zeroth hour, funny people and their made up symbolic lies.
I like how people think that when zero was realized to be a number they think that means it can exist. I'm sorry, zero does not exist. That is what zero is, none existence. It is what is inside that little circle we use to show it's concept. If you have 4 apples, and you give away 4 apples you don't walk around with a special magical apple known as your zeroth apple. You walk around empty handed saying, "I have zero apples!"
That is why the month does not start on day zero and then move to day 1. The month starts on 12:00am actually. Which is also the end of last month in our macro world. Maybe some electrons get to tunnel into that zeroth second and freeze in time for who knows how long then popup somewhere else randomly. But that's the great thing about the universe! It's made up of real existence held together by irrational imaginary chaos.
Maybe that's where my mind lives, I hope you can join me there too and not just try to argue unsuccessfully against me. Because I would love to hear a justification on how, "The rollover from 12 to 1 happens an hour later than the change between a.m. and p.m." this sentence is even remotely disadvantageous.
I've noticed that in Judaism and Seventh Day-Adventist faiths they celebrate the next day at sunset (as opposed to arbitrary time of 12:00am or 00:00). Is there any specific term for their start of the next day at Sundown? CaribDigita (talk)
Informal speech and rounding off
First, let me state my background, I am an Englishman living in America. I agree with the observation that the phrase "half five" (meaning 5:30) is not understood in America (and is often met with the question "is that 4:30 or 5:30?"). I live in the midwest (Chicago) and I've never heard "half five" used to actually mean 4:30 as this section goes on to suggest, though if it's use is limited to the German communities, I could have missed it.
I didn't hear 5:45 referred to as "a quarter of six" until I moved to America (and to this day, I never remember if it means "a quarter TO six" or "a quarter PAST six"), so I'm guessing that is just a US phrase and not a UK phrase.
[Since the Latin word meridies means noon or midday, it is illogical to refer to noon as either "12 a.m." ("12 ante meridiem", or "12 o'clock before noon") or as "12 p.m." ("12 post meridiem", or "12 o'clock after noon"). On the other hand, midnight could logically be called either "12 p.m." (12 post meridiem, 12 hours after the previous noon) or "12 a.m." (12 ante meridiem, 12 hours before the following noon); "x a.m." no longer means "x hours before noon", but "x hours into the day but before noon" or "x th hour before noon".]
really this whole beginning is nonsensical and without any citation -- it appears to be an invention from someone who looked up the latin terms for AM & PM and then used some sort of convoluted "logic" to create an issue. Yes, there is confusion and there are people who do not know whether 12 pm refers to noon or midnight -- but that's only because they don't know which designation means noon & which one means midnight, they aren't confused by the latin.
In common parlance in the USA, which predominantly uses a 24 hour clock, the answer is far simpler than this invented, uncited rationale:
12 pm has always meant noon. Period. End of story.
& that's the main thing people want to know who are confused about whether 12 pm means noon or midnight, not the invented rationales for why there's no answer, when there is a correct answer.
If another culture or nation that uses a 24 hour clock uses 12 am to mean noon & the reverse, please go ahead and cite a legitimate source.
This passage:
[The American Heritage Dictionary of the English Language (Fourth Edition, 2000) has a similar usage note on this topic: "Strictly speaking, 12 a.m. denotes midnight, and 12 p.m. denotes noon, but there is sufficient confusion over these uses to make it advisable to use 12 noon and 12 midnight where clarity is required."]
& the subsequent attempts to support the invented rationale of the opening paragraph of this section do NOT speak or give support to the above invented issue -- it simply notes that there's "confusion" over which denotes which, but not because of any reference to the latin terms or when the sun is straight overhead. People just don't know because they usually use "noon" or "midnight" whenever there's any chance of confusion. & each subsequent citation example that speaks to this issue simply ends w/ the same -- 12 pm means noon, 12 am means midnight, & they acknowledge there are people who don't know this.
IMHO, invented controversies in passages such as the above hold wikipedia up to the ridicule & disdain it sometimes rightly deserves. Might as well give some space to the flat earthers on the "Earth" entry.
This statement appears incorrect to me - On the other hand, midnight could logically be called either "12 p.m." (12 post meridiem, 12 hours after the previous noon) or "12 a.m." (12 ante meridiem, 12 hours before the following noon);. I see no indication in this article nor anywhere else that the designations of am/pm refer to anything other than that specific day, i.e. they are relative terms - relative to the day in which the specified noon occurs. However, 12 hours after the previous noon is 12:00 a.m. the next day. Once again I believe we are falling in the trap of describing the 12-hour clock within the context of the 24-hour clock instead of the other way around. It do not see how it can be logically called 12:00 p.m. of the same day. I would say this entry needs to be removed or reworded. JackOL31 (talk) 20:21, 8 September 2011 (UTC)[reply]
I think the sentence is just pointing out the logic of "12 hours after noon gives midnight" (not necessarily the next day). I agree that the article would benefit from a re-write in a more factual and less opinionated style. Dbfirs21:48, 8 September 2011 (UTC)[reply]
If we're going to re-write the article (and possible even if not), I suggest we should consider renaming it, eg to "12-hour clock system" or similar, because it's about the "time conversion convention", ie how we denote time - not just about physical clocks. (Many 12 hour clocks do not include an am/pm indicator at all.) Actually, there is quite a bit that's common between this and the 24-hour clock article, and it is almost impossible to talk about the 12-hour system without defining it by reference to the 24-hour system. Perhaps we should seriously consider merging the two articles. Mitch Ames (talk) 12:06, 9 September 2011 (UTC)[reply]
This article is about "the" 12-hour clock, not about "a" 12-hour clock. Adding "system" is wholly unnecessary and would be a change to a less common name. I agree about the relative nature of the clock times. There is no logic in using 12:00 p.m. for midnight at the beginning of the day. −Woodstone (talk) 15:49, 9 September 2011 (UTC)[reply]
I would like to see the entire first paragraph under Confusion at noon and midnight replaced. I suggest something along the lines of: Although the Latin word meridies means noon or midday, the de facto convention is to use the designation of post meridiem for 12 o'clock noon.
Woodstone, I disagree that "This article is about 'the' 12-hour clock ... adding 'system' is unnecessary". Using a definite article instead of an indefinite article doesn't change the meaning of the noun-phrase "12-hour clock". If it does make a significant difference, should the article be renamed to "The 12-hour clock"? I don't think so - and WP:DEFINITE also says we should not. But if "the 12-hour clock" is so different to "a 12-hour clock", we have a problem, because we need an unambiguous title. As the first sentence says, this article is about "a time conversion convention", not "an instrument used to indicate, keep, and co-ordinate time". I think that the article title should clearly reflect the contents, which are not limited to the physical clock. Mitch Ames (talk) 06:25, 10 September 2011 (UTC)[reply]
"clock system" table - midnight and noon
I've changed the "clock system" table again, to show the numeric time first, then midnight/noon in brackets. The number is first because that's what the clock actually shows. Midnight/noon is a clarification for the reader so in brackets. I've removed "start/end of day" because it's self-evident, and covered by 12-hour_clock#Confusion at noon and midnight. Mitch Ames (talk) 02:16, 4 February 2011 (UTC)[reply]
The article is about the system of the 12-hour clock, as header of the table indicates. That is not just what a (digital) clock shows, but the full denotation of time. The last row is about midnight at the end of the day. At midnight the date changes. Which date prevails is an issue. In the 24-hour clock midnight at the end of 31 Januari can denoted as 24:00 (this is not uncommon in contracts). In the 12-hour clock you would never denote the same instant of time as 0:00 a.m. on 31 Januari. Therefore it does not make sense to put 0:00 in the last row. −Woodstone (talk) 04:47, 4 February 2011 (UTC)[reply]
I concede your point about the system being more than just the display in a clock, and I'm not going to quibble over the order of (for example) 12:00pm vs noon. However I still think that the table needs changing, because:
The 12-hour clock system must surely include actual physical clocks, both digital and analogue - it's a clock system, not a time system - so we should include in the table the time as shown on most clocks at midnight. I've yet to find one that actually says "midnight" on the analogue face or digital display. Note also that the article's lead paragraph says "Each period consists of 12 hours numbered: 12 (acting as zero) ..." No mention there of midnight.
Similarly the 24-hour clock system must surely include physical 24-hour clocks - a good many of which display 00:00, not 24:00.
Thus I suggest that the "midnight" row should show "midnight (end of day) 12:00 am *" and "24:00 (end of day) 00:00 (start of next day). Mitch Ames (talk) 08:58, 4 February 2011 (UTC)[reply]
In the 12-hour clock the time midnight at end of day cannot be denoted meaningfully by 12:00 a.m. That notation is only meaningful for begin of day (although not totally unambiguous, since it sometimes might mean noon as well). :Since midnight at end of day is the same instant as midnight at begin of the next day, a physical digital clock cannot display both. It has to make a choice. In the 12-hour clock the only available choice is never to display end of day, but skip right to 0:00 a.m. the next day. So the last line should be blank. In practice almost all digital physical 24-hour clocks do the same, going right to 00:00. This is especially clear on clocks that have a date display as well. There are some very exceptional cases of a clock (without date) actually showing the end of day as 24:00 for a full minute. IMHO not worth summarising in the table.
In written notation, the 12-hr clock still has no notation for end of day. So work-arounds like 11:59 p.m. are used. In the 24-hour clock the notation 24:00 is clearly at the end of the implied or written date, and is regularly used in time schedules and especially in contracts (validity form begin of first day till end of last day).
I understand and agree with most of what you're saying - but I still think the table needs entries in those cells. Our disagreement appears to be about the purpose of the table, rather than how a particular time should be denoted. The purpose of the table is not stated in the article, but perhaps it should be. It might help if you answer these questions:
What is the purpose of the table? Ie what exactly is it intended to show?
Does a "clock system" include actual physical clocks? (If not, perhaps the table and the article need renaming.)
As a reader of the article, I assume that the table shows me what a digital clock would show at a given time. Is this assumption correct and/or reasonable? (If not, the article needs to address Q1 above.)
Is "midnight end of day" a meaningful time? (eg I went out at 7pm on Saturday for dinner and a movie, and returned home at midnight the same day.)
If yes, what would I see on my digital clock at that time?
Why isn't the answer to Q5 in the table? (See Q1, Q2, Q3.)
Perhaps (depending on the answers to Q1, Q2, Q3) the table should be expanded to have three columns: Notation when writing the 12-hour time (existing "12-hour" column), Time displayed on 12-hour digital clock, 24-hour notation. For 24:00 in the "12-hour digital clock" column we would put "12:00a (of the next day)". Mitch Ames (talk) 03:09, 5 February 2011 (UTC)[reply]
I'm assuming for now that the results of this discussion will be similar to that of #Confusion at noon and midnight - Table - Digital 24-hour clock displays below, so there's probably not much point in trying to have both discussions at once. Once the matter below is resolved, the answer here should become more clear. Woodstone, can I suggest that you add the asterisk back to the "midnight (end of day)" row of the table. Regardless of our differing opinions as to the 1st column should show a number, presumably the asterisk still belongs. Mitch Ames (talk) 12:55, 11 February 2011 (UTC)[reply]
(moved from below and edited to fit) I have put (shown as start of next day) in the table. That recognises the validity of the demarcation, without suggesting that there might be 3 different times 12:00 in the 12-hour clock. For me it's a good compromise. −Woodstone (talk) 12:16, 12 February 2011 (UTC)[reply]
:Are you referring to the table in the lead section or the table in the "Confusion at noon and midnight" section. If the former, could you please move (or copy and strikethrough here) your comment up to #"clock_system" table - midnight and noon. There are two tables in the article, with different formats and potentially different requirements (although the discussions are clearly related), and it might be easier if we keep the discussions separate. Mitch Ames (talk) 12:50, 12 February 2011 (UTC)[reply]
Looking at the Clock Systems table, I do not understand the issue with 12-hour notation entry for start of day listed as 12:00 a.m. and the entry for noon listed as 12:00 p.m.. That is what it is actually denoted by on 12-hour timepieces which carry an am/pm indicator. Regardless of whether we consider timepieces or not, that is the 'de facto' notation for those points in time in the 12-hour system. To simply put an 'asterisk' or the term 'noon' does not reflect the 12-hour time system as it is used. The point regarding possible confusion is still made numerous times elsewhere in the article and we don't have to overdo it in this table. The value of 12 a.m. for beginning of day, despite the claim in the article, is a consistent notation since am/pm is relative to noon for that day and the notation does not span days. Therefore, 12:00 a.m. (beginning of day) is most certainly in the same day and is most definitely ante meridiem. Now 12:00 p.m. is a misnomer since noon is not post meridiem, however it IS the de facto usage for that time occurrence. I believe we are over thinking this. Lastly, midnight end of day does not exist (i.e. not accommodated) in the 12-hour system but I can go along with the entry used. JackOL31 (talk) 21:55, 23 January 2012 (UTC)[reply]
I have made the change I described at the beginning of the previous comment. Clocks with an am/pm complication actually indicate a.m. at beginning of day and p.m. at noon, so the table should reflect that. Regardless of new recommended usage suggestions, the a.m./p.m. system still operates in that manner. The footnote asterisk was retained to directs the reader for more detail. JackOL31 (talk) 20:34, 17 March 2012 (UTC)[reply]
.Exactly! Specifically in the am/pm system, the time is 12:00 a.m. when it is 00:00 in the 24-hour system and similarly it is 12:00 p.m. when it is 12:00 in the 24-hour system, regardless of whether a physical clock displays the the complication or not. That is how it is denoted in the am/pm system and the table should reflect that information. A recommendation regarding how one should avoid confusion does not change that fact nor did the edit I made change the reference to the addl informational section. BTW - I offered that change 2 months ago without objection. JackOL31 (talk) 23:14, 17 March 2012 (UTC)[reply]
But the article is about the 12-hour clock system, not the majority convention on use of a.m. and p.m. I've no doubt that we can find many sources to support your claim that the time is 12:00 p.m. at noon, but also many other sources that advise against using this convention. Dbfirs23:56, 17 March 2012 (UTC)[reply]
Do you have any evidence that the de facto notation for the 12-hour system was somehow changed to eliminate the am or pm designator for the 12:00s? Is the recommendation regarding how to avoid confusion in common usage evidence that it has been removed from the 12-hour system? Are you suggesting clocks with the am/pm designator are not implementing the 12-hour system, i.e. they are implementing some other time system notation? If so, where is the wiki for that time system? Why wouldn't the actual implementation of the 12-hour system on timepieces be evidence that beginning of day is represented by 12:00am and noon is represented by 12pm in the 12-hour system?
If any one of the millions of people worldwide looks down at their 12-hr clock on a MS Windows PC and sees the value '12:00 AM' or '12:00 PM' displayed, why can't they go to the wiki on the 12-hour system and find that entry in the 12-hour table?JackOL31 (talk) 14:42, 18 March 2012 (UTC)[reply]
Well I agree that the article should show the common convention, but I'm not convinced that it is an essential part of the 12-hour clock system, nor that it is logical. I'll accept your addition for the sake of helping people who want to know what 12 a.m. usually means. Dbfirs20:56, 18 March 2012 (UTC)[reply]
Respectfully, I beg to differ. It is not just a common convention, it is the actual de facto standard and the actual implementation of the 12-hour system for timepieces. It is an integral part of the 12-hour system to have a continuum of time values each having the necessary am/pm designation. Without that designation at each point, the system no longer has a consistent structure. For what it is worth, the 12-hour system does not accommodate dual naming conventions for a single point in time and the naming is relative to the current day. Therefore, 12am is most decidedly ante meridiem and a logical and consistent name for that point in time. On the other hand, 12pm is most decidedly a misnomer for that point in time. However, for good or for bad, the common person does not pay attention to the Latin meanings or the scientific implications of the designations. The designation a.m. simply indicates the first half of the day while the p.m. designation simply indicates the second half of the day (the repeat of the numerical times). In that respect, it is logical and consistent.
I would also add that 12:00 am (SOD) & 12:00 pm (noon) designations are not what they usually mean, but what they do mean. I'll address that in a different talk section. JackOL31 (talk) 18:06, 20 March 2012 (UTC)[reply]
Confusion at noon and midnight - table - midnight, end of day, for clocks
Should each "digital clock display" row in the table in the "Confusion at noon and midnight" section show an entry for both midnight start of day and end of day? Mitch Ames (talk) 01:11, 12 February 2011 (UTC)[reply]
Woodstone, you've removed the entries for "midnight, end of day" for "Digital 24-hour clock displays" and "12-hour digital clocks". I disagree with this. At midnight at the end of the day, none of my digital clocks go blank - they all display something. Just because midnight at the end of Monday is the same as midnight at the beginning of Tuesday doesn't make the former an invalid time. Just because my clocks don't know what day it is doesn't make "midnight end of day" just not happen. I suggest that it is appropriate to put the relevant values in these cells. Mitch Ames (talk) 10:07, 4 February 2011 (UTC)[reply]
As explained above, a physical digital 12-hour clock never shows midnight at end of day. It passes right through to begin of the next day. So the lines are rightfully empty. −Woodstone (talk) 14:01, 4 February 2011 (UTC)[reply]
As with the "clock system" table, our disagreement here appears also to be the purpose of the table. Again, the purpose of the table is not stated in the article, but perhaps it should be. Again, it might help if you answer these questions:
What is the purpose of the table? Ie what exactly is it intended to show?
As a reader of the article, I assume that those rows of the table tell me what 12- and 24-hour digital clocks show for the time indicated by each column. Is this assumption correct and/or reasonable? (If not, the article needs to address Q1 above.)
Is "midnight end of day" a meaningful time? (eg I went out at 7pm on Saturday for dinner and a movie, and returned home at midnight the same day.) Presumably it is, because there's a column in the table for it.
If yes, what would I see on most 12- and 24-hour digital clocks at that time?
Why isn't the answer to Q4 in the table? (See Q1, Q2.)
The table should show how times within the day are stated (in a document) or shown (on a clock). For convenience comparison is made to the internationally defined standard 24-hour clock system.
The table should not only reflect clocks, also document usage.
Many time periods have a natural extent, like a day, week, month or year. There is a case for using the end of such a period as demarcation (not the beginning of the next period).
Clocks do not show periods, but are real time. They will have to choose. Normally clocks show the time truncated, changing at the beginning of their shortest display interval. It is not logical to show 24:00 (and exceedingly rare, certainly never on clocks that also show a date). In my view we can omit this rarity from the overview table.
I still think it is better to leave the end of day blank for tyhe 12-hour clock, since it duplicates the first entry.
The table should show how times ... are ... shown on a clock
The table should reflect clocks (as well as other things)
There is a case for using the end of [a day] as demarcation – ie "midnight end of day" is a meaningful time.
Then we get stuck:
4. I ask: "What would I see on a clock at midnight end of day?" You neglected to answer the question explicitly - so I'll answer it for you: 00:00 (usually) or 24:00 (rarely). Note that all clocks show something - a display of some description is not a "rarity".
5. I ask: "Given 1, 2, 3 (which we agree on), why isn't the answer to 4 in the table?" Your answer: "it duplicates the first entry". Assuming that you mean the first column, other rows also have the same value in both midnight columns, so I don't think that is sufficient grounds. Given 1, 2, 3, surely one must logically include the answer to 4 in the table.
Does anyone else have an opinion on this? Can someone point out any flaw in the logical progression that given 1, 2, 3, the answer to Q4 should be in the table? Mitch Ames (talk) 13:16, 9 February 2011 (UTC)[reply]
Clarification on Q4. A physical digital clock can show either the start or the end of the day, not both. So logically one of the lines should be empty. Clocks showing 24:00 are so rare that we don't need to mention them in the overview table. A passing remark in the section is enough. −Woodstone (talk) 17:18, 9 February 2011 (UTC)[reply]
You keep saying that the digital clock can show one or the other but not both - which is true, but not the point. In simple terms: I go out 7pm on Saturday for dinner and a movie, and return home at midnight the same day ("midnight end of day"). As I arrive home, I look at my 24-hour clock. What does it show? Answer: 00:00 (midnight start of next day). I still don't see why this answer can't be put into the "display at midnight end of day" column of the "what does the digital clock show?" row of the table. We agree (Q1) that the table's purpose is to tell the reader what is displayed, we agree that I can refer to "midnight end of day" as a time, and presumably we agree that (most) clocks will show 00:00 (indicating the start of the next day) at that time - so what's the problem with putting that in the table?
If the table's purpose were to tell me what the time was when a clock was displaying 00:00, then you might have a point that there should only be one entry for that value (although one might argue that the "time" could be either midnight start of day next day or midnight end of day previous day) - but that is not what the table is apparently for.
I repeat my request for others' opinions, and/or explicit answers to my original Q4 (if anyone disagrees with my claim that the answer is 00:00 usually, 24:00 on some clocks), and or someone to point out the flaw in my argument. Mitch Ames (talk) 11:57, 10 February 2011 (UTC)[reply]
The point is that the 12-hour clock simply cannot denote or display the end of a day (but skips to the start of the next day instead). The p.m. is reserved for noon and a.m. is by definition before noon (not at the end of a day). So entering that 12 a.m. at end of day is misleading and contradictory. The same is true for almost all 24-hour digital clocks. The only use for 24:00 is in writing, typically only as the end of an interval. −Woodstone (talk) 16:47, 10 February 2011 (UTC)[reply]
Yes, and my point is that the table should show what a physical clock will display when I look at it at midnight end of day. Clearly we are going around in circles here. Does someone else have an opinion on the matter? And/or do you want to add some text to the article explaining what the purpose of the table is. Mitch Ames (talk) 11:41, 11 February 2011 (UTC)[reply]
As an aside, I notice that the "Written 24-hour clock, ISO 8601" row has entries for both midnight start and end of day. I suggest that this row should just be "ISO 8601" (which is well-defined "style"), to avoid confusion with an actual physical clock - which we both agree cannot show both 00:00 and 24:00. 8601:2004 does not use the term "clock" at all" except to mention in its definition of standard time of day that "Standard time of day is called “clock time” in IEC 60050-111." Mitch Ames (talk) 11:52, 11 February 2011 (UTC)[reply]
All automatically set digital clocks I know of display a truncated time; a clock that displays minutes would begin to display 11:30 at 11:30:00.00... and continue to display 11:30 for a period of 1 minute. The time displayed by a manually set clock depends on the person who set it. If, for example, the clock-setter was listening to CHU (callsign) and started the clock at the moment the minute tone sounded, then as far as humanly possible the clock would display truncated time. I think that's how everyone sets a clock, but I suppose someone could set the clock at the end of the minute.
If a correct digital clock with a truncated display, as described, were to display 24:00, it would only do so for an infinitesimal time, so short that no human could ever observe it, because at 00:00:00 + ε the correct display becomes 00:00 (where ε is a very small positive number such that 0 < ε << 1 s). In as much as a digital clock that displayed 24:00 would be incorrect according to the way nearly all people set clocks, I think we should not include a description of such a clock unless someone can provide a citation to a specific clock model that behaves in this way and was sold in reasonable numbers (following the WP:NPOV policy that the viewpoints of tiny minorities need not be presented in Wikipedia). Jc3s5h (talk) 16:46, 11 February 2011 (UTC)[reply]
If by "this" you mean the claim that some digital clocks show 24:00 at midnight... I copied it from the last paragraph of 24-hour clock#Midnight 00:00 and 24:00 and added {{Citation needed}} to both. However in the absence of any reliable source I am happy to delete that row from the table. It doesn't affect the main dispute of this section, which is whether each "digital" clock row(s) in the table should show an entry in both the midnight start of day and midnight end of day columns. Mitch Ames (talk) 06:03, 12 February 2011 (UTC)[reply]
There used to be a picture of a clock on a kitchen appliance showing 24:00. A rare example of a digital clock showing midnight as 24:00 instead of the standard 00:00. This variant notation has been used by at least one European supplier of kitchen appliances. The owner posted this in talk:
I got a bit curious about why some ovens display 24:00 instead of 0:00 and which ones do it. So I emailed the BSH (Bosch-Siemens, who make Neff ovens too). Surprisingly I got a quick reply. Kudos to them for taking an interest! Here is what they had to say:
I had never noticed this and was not aware convention dictates that the clock is expected to show 00:00 as opposed to 24:00.
I believe that ISO 8601 is the relevant standard, but understand that this does not define whether 00:00 or 24:00 should be used and appears to actually recognise both as valid times. 00:00 however, appears to tbe the prefered display for midnight, and although some argue 24:00 is not a vlid time, there seems no reason (other than "convention" why we cannot use 24:00.
Frankly, I suspect that this is nothing more sinister than the fact that this is simply the way the clock was configured originally. I would be surprised if there was any attempt to differentiate the clock and the timer functions (why would there, as for every other minute of the 24 hour day, the settings are identical). Put simply, I think this is just the way it is.
As for Siemens and Bosch, [Borb] will no doubt be pleased to learn we stick with his prefered 00:00 display at midnight.
Agreed. I have deleted that row from the table. Now can we please get back to the original dispute, which is whether the digital clocks rows in the table should show "00:00 (start of next day) in the "Midnight (end of day)" column.
The "midnight confusion table" shows the meaning of the various notations in the selected styles. Again here, we should recognise that physical digital clocks simply never display end-of-day. They always show (now the exception is gone) the start of the next day. So in my view a dash is the best value. If you prefer we can also put a text like (shown as start of next day).−Woodstone (talk) 15:13, 12 February 2011 (UTC)[reply]
There appears to be some confusion about the purpose of the table. (Remember that the purpose of the table is not stated in the article.) In my original question 1, I asked (03:28, 5 February 2011) "What is the purpose of the table? Ie what exactly is it intended to show?". Your original answer (13:27, 8 February 2011) was "The table should show how times within the day are stated (in a document) or shown (on a clock).", which is much the same as what I had assumed all along. However now you are saying that the table "shows the meaning of the various notations in the selected styles". This is not the same purpose.
For the first purpose (P1), a reader of the article should be able to take an existing clock/document/style S (eg a 12-hour digital clock) and a valid expression of time T (midnight end of day), look at the intersection of the corresponding row and column, and read off what value V the clock/document would show for that combination. As I have previously stated my digital clock will show V as "12:00 a.m." so that is what I expect to see in the table. For P1, there should generally be exactly one applicable row (S = 12-hour digital clocks), one column (T = midnight end of day) and thus once intersection cell with one value (V = 12:00 a.m).
For the second purpose (P2), however, a reader should be able to look up (ideally find in a row and/or column) a style S (specific clock or document, eg 12-hour digital clock) and a specific "notation/value" V that appeared on a clock or in a document (eg 12:00 a.m.) and find in the table (ideally at the intersection of row/column - but not in this case) what that value means, ie find T expressed in "plain unambiguous English". For P2, there may be multiple values that satisfy some input criteria (S, V), because we know that some notations (eg V = "midnight" with no qualification) are ambiguous. For my case of S = 12-hour clock, V = 12:00 a.m, there is currently only one column with V = 12:00 a.m. and that is T = start of day. This is because (as you rightly point out) the clock's time does not ever reach end of day, it rolls over from 11:59 to start of day. So from the clock's point of view, it is start of day - regardless of my perception that it is end of day (eg as I'm going to bed).
Both P1 and P2 are useful purposes. The table appears to be currently structured for P1, in that row = S, column = T, and V = intersection of row/column. However it works for P2, because of a limited number of columns (3). I find row = S, then I check all columns for the value V and my output T is the title of the columns(s) in which I found V. In ambiguous cases, I find V in multiple columns, so I have multiple outputs T.
Now we could add some text to the article explaining that the purpose of the table is P2 (and not P1, despite being structured that way), and thus why the clock rows only have one midnight entry. Or we could change the structure of the table somehow so that the inputs S and V are row and column, or combinations of S, V per row with a single output column for T, to better suit purpose P2 - but this would probably be impractical. But the existing table can easily serve both P1 and P2 with little modification - all we have to do is add V = 12:00a.m/00:00 (start of next day) to the intersection of the "clock" row and the midnight end of day column.
Does this make the table any more confusing for readers using the table as P2? I think not. In fact, I think it adds value. It more clearly indicates the fact that when someone asks the question "what is the meaning of the display 12:00 a.m. on my digital clock?" (in your words "the meaning of the ... notation on the selected [clock]"), the answer is both midnight at the end of one day and simultaneously at the start of the next day. Surely it is more useful to give the "meaning" in human terms (midnight is both end of one day and start of the next), rather than clock terms. When I ask "what does this value mean", I don't care that it means for the clock, or that the clock can only go up to 11:59 p.m. - I want to know what it means to me.
To avoid going once more in the same circle, consider a digital clock that displays both date and time. On 13 February at midnight at the end of day it would not show 13 February 0:00 a.m.", but 14 February 0:00 a.m.". The clock does not show end and start simultaneously, it only shows the start. The end of day is never shown on such a clock and the table entry should be empty. In other words, the table takes on its meaning in the context of a specific date. Relative to that date 0:00 a.m. can only be shown at the beginning. −Woodstone (talk) 14:24, 13 February 2011 (UTC)[reply]
This is a valid point - for a digital clock that shows the date as well as the time (eg videocassette recorder, digital video recorder, wristwatch with date). However it does not apply to a digital clock that does not have the date (eg the alarm clock in my bedroom, the typical alarm clock pictured in this article, the digital clocks in my ovens, air-conditioners, car). And even for clocks that include date, I would still maintain that for purpose P1 a reader could legitimately ask "what will this clock display at midnight end of day". I would answer that question - and expect the table to answer the question - "12:00am / 00:00 (start of next day)". How would you answer the question - surely not "the clock will not display anything" (which is what the current table says) or "your clock only counts up to 11:59pm, so don't look at it when you're going to bed at the end of your day". Possibly we need separate rows for clocks with/without a date - but I think that will just complicate matters unnecessarily.
It would help convince me of your case if you could point out what's actually wrong with my reasoning. To do this, could you please:
State explicitly what the purpose of the table is, ie my original question 1. You originally answered this as purpose P1 described in detail above, but then changed it to a different purpose P2. Do you think that table exists for purpose P1, or P2 or both? Or something else? Specific examples may help, just as I did in my description of P1 and P2. If there is some flaw in my description of the purposes P1, P2 tell me exactly what is wrong. (How can we agree on what should be in the table if we don't know what the purpose of the table is, or how we expect a reader to use it?)
Explicitly answer question 3, is "midnight end of day" a meaningful time for me refer to? (If the answer is "no", life will be much easier because we can delete that whole column from the table!)
Explicitly answer question 4 (for a clock without a date). Imagine a reader asks the question - as I have done several times now - "when I look at my 12h clock at midnight end of day, what does it display". In plain english, how would you answer? If it's not a sensible question, tell me why? There's no point telling me it's not a meaningful question because of how the clock works - I assure you I can look at my clock at midnight at the end of day and it does display something! If you don't believe me, try it yourself.
You keep explaining how the clocks keep time, but the problem is now about how clocks keep time, it's about what's in the table. Obviously the two are related, but I can't see (in your statements) any logical progression from the former to the latter. I've presented some specific scenarios and linked them directly to specific usage of the table, with (what appears to me to be) a clear logical progression from scenarios to table contents. If you think my reasoning is incorrect, please point out where I'm going wrong. Mitch Ames (talk) 13:45, 14 February 2011 (UTC)[reply]
Can we please have some input from other editors on this. Surely someone else out there must be able to confirm my view, or point out what's wrong with my reasoning! Mitch Ames (talk) 13:47, 14 February 2011 (UTC)[reply]
I still think the fundamental disagreement is rooted in the unspecified purpose of the table. Perhaps the solution is to add a title to the table stating what the table contents are actually intended to be (rather then what the purpose of the table per se, ie how we expect the reader to use it). Then for the the missing entries, a note explaining why they are missing (since it is not necessarily obvious). For example:
* Digital clocks never reach midnight at the end of the day. Instead they wrap from 11:59 p.m. or 23:59 to midnight at the start of the next day.
The wording might need a bit of tweaking, the asterisk should perhaps be a numbered note using proper wiki syntax, but this illustrates the general intent. The important parts are that:
The table has a title indicating that it shows the time as denoted by various devices/style (eg it's from the clock's perspective, not the person looking at the clock at midnight end of day)
I was tempted to write a nearly essay-length response to this about how digital clocks work and why 24:00 is never a valid displayed representation of time on a clock (even though it's valid as a representation of an exact instantaneous moment) but in the end it didn't have much to do with my conclusion as it relates to this topic - consider yourselves to have dodged a bullet =)
It's clear that while it's possible to define 'midnight end of day' and 'midnight start of day' as different conceptual representations of the same thing, and while some systems allow this when referring to zero-length instants, in practice it is almost never seen. Do the few exceptions then justify an entire extra column in the table? My feeling is no. This table can be more cleanly represented with 'midnight' and 'midday' columns, where the 'midnight' column contains multiple values where appropriate (e.g. '00:00/24:00') and attach a table footnote if explanation is needed (e.g. '00:00 refers to midnight at the start of the day and 24:00 refers to midnight at the end of the day, though in practice 24:00 of one day is the same moment in time as 00:00 of the next day' though this could use better wording, obviously). This essentially makes the table built around the rule rather than the exception, but still allows you to make mention of the unusual cases as necessary.
On a related note, I don't agree that the 'de facto US legal standard' should appear in the table. The legal standard uses 00:01 and 23:59 explicitly to avoid making reference to midnight, it doesn't define midnight as one of those two values. TechnoSymbiosis (talk) 05:33, 16 February 2011 (UTC)[reply]
Avoid or define? Are there any legal precedents where a car accident took place at 12:59:30 p.m. on the last day of validity? If the insurance has to pay, the notation "defines" (for legal purposes) midnight. If they don't have to pay, they "avoided" midnight. My guess would be that any time on the last date is included in the contract in such cases. −Woodstone (talk) 08:45, 16 February 2011 (UTC)[reply]
I disagree that midnight is defined as 23:59 (or 11:59pm), but I don't have any US contracts on hand to serve as demonstration. My understanding is the reason 23:59 or 11:59pm is used is expressly to avoid using the term midnight, which is understandable ambiguous. Ambiguity is a Bad Thing in legal contracts, since it tends to rule in favour of the interpreter (if I said a bill was due by Wednesday, I may have intended to mean the beginning of the day but the other party could reasonably interpret it to mean the end of the day) so they try to avoid it where possible. In this sense I believe the common usage in legal contracts is to avoid midnight and use an unambiguous nearby figure than to define the term midnight itself as something it's not. TechnoSymbiosis (talk) 20:29, 17 February 2011 (UTC)[reply]
It's a fact that contracts in the U.S.A. sometimes state validity till 12:59 p.m. on the last day. Question remains what would happen if you have a car accident at 12:59:30 that day. Will your insurance have to pay up? Literally no, according to intent yes. −Woodstone (talk) 05:23, 18 February 2011 (UTC)[reply]
I'd like to improve the article, because I still think it is wrong as it stands, but I can't seem to get any specific responses to my specific reasoning or suggestions. Does anybody object to my changing the table to be something like this?
Yes, I know the feeling, WP editing and "Talk"ing can be quite unnerving. I mostly agree with your proposal above, but would like to combine with proposals in the section on ISO below as in:
* Digital clocks never reach midnight at the end of the day. Instead they wrap from 11:59 p.m. or 23:59 to midnight at the start of the next day. ** Likewise the written 12-hour clock wraps immediately to the start of the next day
OK, I've updated the table, mostly from your version above, but with some variations. I've put "written ... time" (or "...style" in the ** note at the bottom) instead of "written ... clock". I think it is important to clearly distinguish between an actual clock and the time when written down on a bit of paper - ie by not using the word clock unless referring to an actual clock. Also ISO 8601 doesn't use the word "clock". Mitch Ames (talk) 05:58, 19 February 2011 (UTC)[reply]
Hi. I just read this article and saw "Digital clocks never reach midnight at the end of the day." which is simply not true. I've used several cookers over the years that have displayed 24:00 for a minute at midnight. I would be the first to say it shouldn't happen, that it's wrong, etc. but this statement should not be as bold as saying digital clocks "never" reach midnight. Perhaps "typically" or "usually" but the word never is just not correct. I was going to correct it but having seen all the talk here I'm just going to suggest that the word "never" be replaced with "usually". squish (talk) 14:06, 12 February 2012 (UTC)[reply]
Does anyone else have a concern regarding the Japanese entry in the table? I have a concern given the fact that it cites a blog page written by chiyon? I am also concerned regarding statements such as, At the moment, {Japanese characters} seems to be the correct way to indicate noon in Japanese law. Besides the word seems, the author links no authoritative site of Japanese law. Without the meanings of the Japanese characters with their historical context explained, I don't see how this blog page can be accepted by Wikipedia as a valid source reference (not to mention the fact that it appears to be original research with no cites). I recommend this table entry be deleted unless this information can be validated by a reasonable source reference. JackOL31 (talk) 18:09, 20 March 2012 (UTC)[reply]
Confusion at noon and midnight - Table - Digital 24-hour clock displays
Although most 24-hour digital show midnight as 00:00, according to the last paragraph of 24-hour_clock#Midnight_00:00_and_24:00, "the digital clocks of at least one European manufacturer of kitchen appliances show 24:00 for midnight ... an example being Bosch Siemens microwaves". I propose that the table in the "Confusion at noon and midnight" section should include a row for this, eg:
Forget second para and table in this section. Better to keep the two issues separate. See Talk:12-hour_clock#Clarification_of_what_this_section_is_about below. Mitch Ames (talk) 12:14, 7 February 2011 (UTC)[reply]
The midnight at the end of a day cannot be referred to as the start of the next day. It must be either defined as a separate different notation or it must be undefined. A digital clock can only practically use one notation for any particular smallest precision unit (SPU), such as hour, minute, second. By their nature a digital clock has a SPU (as it is a count of periodic events). The most commonly used convention for time at least in the western world has two interpretations. Interpretation 1 is to display the last SPU completed. This convention is also used long intervals of time; e.g. something that is one year and 364 days old is said to be "one year old" it is not said to be "two years old". The second interpretation is that if your determine or display a smaller SPU the previously known digits do not change. In other world, time is always rounded down. This is used for dates. Stating what year it is does not change if your also state the month. Now a decision has to be made when these two interpretations of the convention disagree. The first SPU after midnight is interpreted by interpretation 1 as the completed day; e.g., 24, 24:00, and 24:00:00 in ISO 8601 and as 12:00 p.m. in some conventions of the 12-hour clock. By the second interpretation, which most people seem to use, the time is displayed as zero completed SPUs in the new day. By this convention, midnight is displayed as 0, 00, 00:00, 00:00:00 in the 24 hour clock or as 12:00 a.m. in some conventions of the 12-hour clock. Therefore, your suggested edits are not profitable for the edification of our readers in my opinion, as only one interpretation is used at a time. Zginder 2011-02-06T06:27Z (UTC)
Could you clarify please: are you opposing:
the addition of the row "Some digital 24-hour clock displays" (ie the changes in my first table above)
the replacement of a dash with a numeric value for end of day (most clocks) or start of day (some clocks)
Whatever you write, please consider that while the instant 24:00 may well be described as the end of the previous day, a time interval after midnight in which the display shows 24:... cannot. How long does it show 24:... anyway? If it displays the seconds, I suppose most people would expect e.g. 3:12:47 to be displayed for a second beginning 3:12:47.00 and ending shortly after 3:12:47.99, i.e., we'd NOT expect common 4/5 rounding. Then, does it go from 24:00:00 to 0:00:01, from 24:00:59 to 0:01:00, or does it go all the way to 24:59:59 before changing to 1:00:00?--Nø (talk) 15:01, 6 February 2011 (UTC)[reply]
In the absence of any feedback on the matter, I've added the row "Some digital 24-hour clock displays" showing 24:00 at midnight end of day. Mitch Ames (talk) 12:23, 8 February 2011 (UTC)[reply]
It's Either Or in either case
An actual 24 hour clock is going to display either 00:00:00 at midnight or 24:00:00 at midnight but NOT both simultaneously. It is in this respect subject to the same limitation as a 12 hour clock, which could not display both 12:00:00 and 00:00:00 at the same time, were the zero hundred hours time conventional with 12 hour clocks.
Going on about the fact that one can, in speech or writing, designate the end of a twenty four hour period as 24:00:00 or its beginning as 00:00:00 is a matter of 24 hour notation, not of 12 hour clocks. The discussion is outside the scope of this article, and exists only because of the implicit assumption that 24 hour notation is superior. Having this here is like having a chart on the superior genetic health of interracial children in an article on arranged marriages. The notion, however compelling, is a POV, and not an appropriate reason for having this implied debate here.
"... the implicit assumption that 24 hour notation is superior ..."
Perhaps it's not necessarily that 24-hour notation is superior, but that ISO 8601 - which uses the 24-hour notation - gives us a well-defined standard reference for comparison. Mitch Ames (talk) 10:57, 7 February 2011 (UTC)[reply]
Also, as stated above, this article is about the 12-hour clock, not a 12-hour clock. It is about the 12-hour clock system, not just physical 12-hour clocks. The concept encompasses both what is denoted in writing to convey times, as well as what clocks or other time displays will show. −Woodstone (talk) 15:02, 7 February 2011 (UTC)[reply]
The fact remains that no clock actually displays both 00:00:00 and 24:00:00. It is either or. And if your response is that we are talking notation and not physical clocks then a 12 hour system could just as easily use 00:00:00 to indicate the end of the shift as opposed to the beginning. Again, the issue here is that the matter of the superiority of the 24 hour notation is unsourced POV which falls outside the scope of the article. μηδείς (talk) 17:51, 7 February 2011 (UTC)[reply]
The article is about the system, encompassing both physical clocks and clock time notations. And in agreement with you I quote myself from section 12 above: since midnight at end of day is the same instant as midnight at begin of the next day, a physical digital clock cannot display both. It has to make a choice.
The 12-hour clock also makes that choice for notation. So a contract, say for an insurance, might specify validity from 1 February 2011 at 0:00 a.m. till 1 March 2011 at 0:00 a.m. The article just compares such a notation without judgement to the international standard that could alternatively specify from 2011-02-01 at 00:00 till 2011-02-28 at 24:00. The former has the same time in a different month, the latter has a different time in the same month.
It might help the discussion if we limit this section "Confusion at noon and midnight - Table - Digital 24-hour clock displays" to whether or not we should add a row for "Some digital 24-hour clock displays" with 24:00 at end of day - ie my first paragraph and table.
In the table in the "Confusion at noon and midnight" section I've changed the row from "Written 24-hour clock, ISO 8601" to just "ISO 8601". The standard does not use the term "clock" at all, except to mention in its definition of standard time of day that "Standard time of day is called 'clock time' in IEC 60050-111". The table has a separate row for "Digital 24-hour clock" (ie a physical clock) and I think it best to avoid conflating the two. Mitch Ames (talk) 09:41, 13 February 2011 (UTC)[reply]
ISO 8601 is only a minority of the use of 24:00. That designation is quite common without adoption of ISO. So "written 24-h time" should stay. −Woodstone (talk) 13:30, 13 February 2011 (UTC)[reply]
I thought it best to not use the word "clock" in the ISO 8601 row, else some readers might think that some actual digital clocks can display both 00:00 and 24:00 - which we know they can't. "24-hour time" is perhaps too ambiguous, because it may imply (to some readers) "24-hour clocks". I suggest we should explicitly list the other (than 8601) uses of 00:00/24:00 - rail timetables, legal contracts etc - eg:
That covers only some of the uses and it omits to specify that it applies to usage in a 24-hour style. Could we make it "written time in 24-hour style". −Woodstone (talk) 14:15, 13 February 2011 (UTC)[reply]
The problem with "24-hour style" is that it is too broad. Not everyone who writes the time in "24-hour" format will use 24:00. Also "24-hour style" is ill-defined and potentially misleading. Trying to define "24-hour style" as something separate to what a 24-hr clock displays is just going to confuse people. Ask a few people if their 24-hour clocks use "24-hour style" - most of them will probably say yes. It is better to list a few examples that are correct, than to make a broad statement that is not always correct. Remember that we only need to give some examples - and add "etc" to the end of the row name - not list every possibility. If we were required to list every possible usage in that row, we'd also be obliged to list every style guide, in every country, that didn't follow 8601 - because the current table only covers some style guides. Mitch Ames (talk) 11:04, 14 February 2011 (UTC)[reply]
(moved up)The only way to denote midnight at the end of the day succinctly is 24:00 (the only alternative being a circumscription). So I do not see an issue of putting 24:00 in a row with header "written 24-hour clock" (written as opposed to displayed real time). −Woodstone (talk) 13:33, 14 February 2011 (UTC)[reply]
I don't understand what you're trying to say here. Which if any specific part of my post of 11:04, 14 February 2011 (UTC) do you agree or disagree with? Do you agree with splitting ISO 8601 into a separate row, or disagree, or don't care? Could you include a table (relevant rows only) showing what you propose, as I have done. Mitch Ames (talk) 13:56, 14 February 2011 (UTC)[reply]
The table should have:
a row for a "digital 24-hour clock" (nothing in end-of-day)
a row for something like "written time in 24-hour clock" (the latter includes ISO 8601), with 24:00 for "end-of-day". No need for examples of usage. Whenever end-of-day is used, it can only be 24:00.
The difference between the rows is not ISO vs time-table/contract/etc, but between real-time vs written. The question is how to name this row precisely. −Woodstone (talk) 14:17, 14 February 2011 (UTC)[reply]
I don't think that a different row/style for "what a digital 24-hr clock shows" vs "written down" is helpful. What if I'm simply writing down the time that I read of my clock? Mitch Ames (talk) 12:14, 15 February 2011 (UTC)[reply]
Given than ISO 8601 is specific and well-defined, whereas "Bus/train timetables, Legal contracts, etc" is incomplete and not so specific, there may be merit in splitting the current row thus:
Some bus/train timetables, some legal contracts, etc
00:00
12:00
24:00
("Reduced accuracy, extended format" is to distinguish from "complete representation, basic format", which would be hhmmss, ie no colons and show the seconds.)
This removes any implication that timetables, contracts etc necessarily follow ISO 8601. It does duplicate the contents of the rightmost columns, but I don't see that as a big problem - certainly it doesn't affect the ability to find information in the table. It also means that we can leave ISO 8601 out of any further discussions of what to call the other row. 8601 is well defined, so there should be little or no disagreement about the contents of that row. Mitch Ames (talk) 11:20, 14 February 2011 (UTC)[reply]
The sentence in the article "midnight could logically be called ..."12 a.m." (12 ante meridiem, 12 hours before the following noon)" is rubbish, because all the other hours are hours after the previous one. So logically, after 11 p.m. the next would be 12 p.m., which would be the same time as 0 a.m. But, of course, logic and usage do not always go well together.--Marschner (talk) 18:44, 27 February 2011 (UTC)[reply]
I loved your point of logic as that drives me crazy. But the Jin of Computer Typing seems to have done its magic. At the above "same time as 0 a.m." could that have read "same time as 00:00." I'm not sure, if wrong sorry for the post
Bio watcher (talk) 14:53, 2 May 2011 (UTC)[reply]
"clock system" table, noon = 12:00 m
Jc3s5h recently changed the noon entry in the "clock system" table from "12:00 p.m" to "12:00 m." because "m stands for meridiem which is noon; noon is neither before or after itself". I don't agree with this because:
The use of "m" by itself is rare or non-existent on clocks, which is the topic of this article. (Although perhaps the article should be renamed to "... clock designation" or similar, because the article covers not just physical clocks.)
The asterisk next to the entry in this table refers the reader to Confusion at noon and midnight which lists several designations, with no indication that "m" is preferable. Perhaps we should list all of them in the "clock system table".
After a previous long and tedious discussion about the table (#"clock system" table - midnight and noon) - which I'm not sure actually achieved anything - I'm not sure I want to go through it all again! However, I still think that any discussion about the contents of the table is meaningless until we agree on the purpose of the table, ie what it is intended to list. A more descriptive table heading and/or some explicit descriptive text would help. Mitch Ames (talk) 04:04, 3 April 2011 (UTC)[reply]
During several automated bot runs the following external link was found to be unavailable. Please check if the link is in fact down and fix or remove it in that case!
During several automated bot runs the following external link was found to be unavailable. Please check if the link is in fact down and fix or remove it in that case!
All times seem to be expressed with a colon, in other places a dot is more common. In the UK, it's not only more common, it's the rule. No mention of this in the article. Also no mention that minutes past the hour below ten can be expressed as a single digit. Five o'clock can be written 5.00 or 5.0 and five past five can be either 5.05 or 5.5 91.85.176.36 (talk) 17:59, 1 June 2011 (UTC)[reply]
The colon is not necessarily "American" - it's used in Australia also. Likewise, ISO 8601 uses a colon (albeit with a 24-hour clock). MOS:TIME says "... 12- or 24-hour clock ... in both, colons separate hours, minutes and seconds". I've added a sentence to Typography to mention the variations. Mitch Ames (talk) 11:13, 2 June 2011 (UTC)[reply]
I've never understood why the dot is "the rule" in the UK. I've never used it here because it causes confusion with decimal notation. I disagree about 5.5 being a valid time. Dbfirs16:27, 24 June 2011 (UTC)[reply]
I don't know about its use in a 12-hour clock system, but 5.5 is a valid time in ISO 8601. Quoting ISO 8601:2004(E), clause 4.2.2.4 Representations with decimal fraction, with my bold emphasis added:
If necessary for a particular application a decimal fraction of hour, minute or second may be included. If a decimal fraction is included, lower order time elements (if any) shall be omitted and the decimal fraction shall be divided from the integer part by the decimal sign specified in ISO 31-0, i.e. the comma [,] or full stop [.]. Of these, the comma is the preferred sign. ... ... Example: 23,3
Yes, thanks for pointing that out, and I agree that 5.5 would logically mean 5:30, but I was replying to 91.85.176.36 who claimed otherwise (and I'm sure the claim is wrong). Dbfirs21:37, 8 September 2011 (UTC)[reply]
Multiple errors by Woodstone
This edit by User:Woodstone contains two errors. First, the letters "Mi" are inserted at the very beginning of the article. Second the article is altered to say "and p.m. begins just after 12:00 and ends just before 24:00." But in fact, midnight can be regarded as either before noon, or after noon, and to say that midnight belongs exclusively to the day that is beginning, rather than the day that is ending, is wrong. Jc3s5h (talk) 13:09, 24 June 2011 (UTC)[reply]
Sorry for accidentally adding two random letters. I was editing on a phone and overlooked it in preview. The question is not if midnight belongs to a certain day, but if 12:00 a.m. does. Clearly, as it is "before noon" of a certain day, it cannot be at the end of that day. If 12:00 is supposed to be midnight, then 12:00 p.m. must logically be (and practically is) noon. In the 12-hour clock using a.m. and p.m., there is no way of expressing the end of a day. This is consistent in the various discussions of the confusion around 12:00 am/pm in the article. −Woodstone (talk) 15:58, 24 June 2011 (UTC)[reply]
The United States is a major English-speaking country, so while the published position of the United States government is not the final word on English usage, it can't be ignored either. NIST states "Are noon and midnight 12 a.m. or 12 p.m.? This is perhaps the trickiest time question of them all. The best answer is that the terms 12 a.m. and 12 p.m. cause confusion and should not be used." Woodstone's unsupported statements, on the other hand, can be ignored.
Also read the "Confusion at noon and midnight" section which mentions several reliable sources which either agree with NIST about the ambiguity of am and pm, or express contradictory claims. Jc3s5h (talk) 16:16, 24 June 2011 (UTC)[reply]
Context is critical
In interpreting the meaning of "12:00 AM" or "12:00 PM" it is critical to know whether it is displayed by a digital clock, written in a statement that is not part of a clock, or displayed by an analog clock.
In a written statement, one must search for contextual clues to figure out which of 3 times is intended (either of 2 midnights, or (erroneously) the midnightnoon between them.
In the case of an analog clock, the same ambiguity is present, because the analog clock can display an instant of time.
In the case of a digital clock that displays the nearest minute, 12:00 AM means the minute following midnight, because except for the first instant of that minute, it is less than 12 hours before the next midnightnoon and more than 12 hours after the preceding midnightnoon. Similarly, on the digital clock 12:00 PM is the first minute of the afternoon. Jc3s5h (talk) 21:29, 26 June 2011 (UTC)[reply]
Everyone knows that 12:XX AM is morning and 12:XX PM is after noon. This article should address why people mentally for some reason can't fathom what to do when XX is zero, even though its exactly the same as when it isn't zero. If 12:00 AM was noon that would mean the AM to PM change over occurred at an infintesmily small moment *after* noon. So on no clock, digital or otherwise, would you even see 12:00 AM as 1 nano-second later it would be technically be 12:00 PM. People just over think the matter and trick themselves. For example you said some people think there could be 2 midnights given a date. Thats ridiculous. A day starts as 12:00AM. There can be no confusion over any time given for any date. Your example of the digital clock approximating the minute is true of *any* clock. All clocks approximate time down to quanta of a photon. This is why 12:00PM is noon, as it makes no sense to make the change over point the instant after this point. — Preceding unsigned comment added by 114.77.184.227 (talk) 11:00, 19 July 2011 (UTC)[reply]
The United States National Institute of Standards and Technology says you're wrong. Since that is part of the US Department of Commerce, and the Department of Commerce together with the Department of Defense (in effect, the US Naval Observatory and the parts of the US Air Force responsible for the GPS system) are legally responsible for time dissemination in the US, I would say your reasoning is wrong in the US. Jc3s5h (talk) 14:13, 19 July 2011 (UTC)[reply]
If one were to see 12:00 a.m. it is vastly more likely to mean midnight than noon. Somehow this de facto interpretation should be clearly reflected in the article. The theoretical musings of one country's authorities notwithstanding. They could be relegated to a footnote. −Woodstone (talk) 14:33, 19 July 2011 (UTC)[reply]
Woodstone claims "If one were to see 12:00 a.m. it is vastly more likely to mean midnight than noon." If I were to see 12:00 a.m. and could not reach the author to obtain clarification, I would act on the assumption that it means midnight at the beginning of the date in question. But as a Wikipedia editor, I demand proof in a reliable source if the article is to take that position.
Stated another way, if I worked for an insurance company, and through some error, a policy had been issued that expired at "12:00 am August 1st", and the insured house burned down at 10:00 am August 1st, I wouldn't like my chances if the policy holder sued, contending the policy was in force.
Considering that some of our readers might write statements, such as expiration dates of contracts, or closing times and dates for acceptance of bids, that may be interpreted in a contentious atmosphere, we should not over-emphasize the meaning in casual writing. Jc3s5h (talk) 14:53, 19 July 2011 (UTC)[reply]
Table in lead section should be consistent re 12 midnight, noon, am, pm
These changes by Dbfirs removed any reference to m or pm for 12 midday in the table to "avoid controversy". This appears to be a reasonable compromise, but for the sake of consistency we should also change the first and last rows to "12 midnight" (keeping the start/end of day and asterisk). Mitch Ames (talk) 13:52, 16 September 2011 (UTC)[reply]
Blank line in the table
Done
There is now a blank line in the "Time as denoted by various devices or styles" table for the entry "Written 12-hour time", with - and ** marks and the ** footnote has been removed. Either the footnote needs to be restored, or the "Written 12-hour time" line needs to be removed.
I came to this article to try to find an answer, when someone writes 12:00 am what do they mean? I have an assignment that must be performed at 12:00 am. Am I to do this job at 12 noon, or 12 midnight? The article is absolutely no help. What I need to know is "What do most people mean when they write 12 am?" Of course, the answer will be imprecise, because some people mean midnight and some mean noon. But what do MOST people mean? Is it safer to assume noon, or midnight? (Obviously, for my assignment, the best approach is to ask for clarification, which I have done. But I haven't received an answer yet, and I need to do the task today if at all possible. The nature of the assignment is such that either answer is entirely possible, no help in deciding which is meant.)
Most people seem to mean midnight (and I think that was what I was taught many years ago, but I've never used the convention because I considered it to be illogical, having also been taught the meaning of the Latin words). My clocks and watches all read 12 noon a few minutes before the local noon or meridiem. Dbfirs21:46, 5 January 2012 (UTC)[reply]
I have rectified the issue regarding 12:00 a.m. and 12:00 p.m. mentioned earlier. Although we may see recommendations to avoid confusion at midnight (b.o.d.) and noon, the actual nomenclature for those points of time is a.m. and p.m., respectively. Regarding the 1953 Ed. for the GPO, I do not see the point of having it in there. It was simply a style manual with an error. The article misleads readers to think the govt actually used 12am/12pm in that manner. While it is humorous to see the error, I'm confused as to why errata from a 60-year old reference is cited. Errata is not allowed to die, even after it has been corrected (2008 Edition)? JackOL31 (talk) 20:54, 17 March 2012 (UTC)[reply]
Apologies for "unrectifying" the issue, but I'm not sure that the convention is universal, even if the 1953 GPO claim is just an error. Dbfirs23:46, 17 March 2012 (UTC)[reply]
Woodstone seems to think that the "rectification" was correct, so I'll accept the viewpoint since I agree that the article ought to show clearly the usual convention, though I still think that it is neither universal nor logical. Dbfirs20:50, 18 March 2012 (UTC)[reply]
Resolved
Done