Why is midnight and afternoon reversed?

The morning begins at midnite and ends at noon. There has to be a standard, since our individual points of reference vary considerably. Even nature conspires to confuse us through constantly varying the durations of light and dark.

12 a.m, and 12 p.m. are both wrong!

The proper time designations are 12 midnight and 12 noon.

The m in a.m. and p.m. refers to the +meridian,_ and is a reference to the time that the sun crosses the meridian, which is astronomical Noon.

People screw it up all of the time. It’s by convention/tradition that AM designates midnight and PM is noon. @zenvelo is right that AM denotes antemeridian/ante meridiem, and PM is post meridien, etc. Some picky people don’t like the use of antemeridianand insist on ante meridiem.

My guess is that when filling out a form it all has to be standardized and there wasn’t space for noon and midnight. Kind of like D.C. isn’t a state, but on some forms for Washington DC you enter the DC in the state section.

I use noon and midnight a lot of the time so there isn’t any confusion.

It’s easy for me to remember 12: midnight is 00 on the 24 hour clock, and so that’s how I remember 12 midnight is AM.

An alternative way to keep it straight if you really need to use a.m. and p.m. is that 12:01 a.m. is one minute after midnight, so midnight must be 12:00 a.m.

Because in the first second after noon it’s already afternoon. True, noon is technically not afternoon, nor is midnight morning, but 1200:00.00000001 (by the 24— hour designation) is definitely past 1200 hours.

Another trick is you only have to remember one, you don’t have to keep both straight. I use this whenever there is two things to remember that I confuse.

For the same reason that the year 2000 was the beginning of this century rather than the end of the last. Any year of the form 2——is considered as belonging to the current century, including the year 2000. Since 12:01 am is in the morning, we include 12:00 am as part of the morning.

@LostinParadise The year 2000 was technically the last year of the 20th century (as well as the last year of the second millennium). 2001 was the first year of the present century. A century is 100 years, starting with the year ending in 01.

You are technically correct, but nearly everyone considers the year 2000 as the first year of the 21st century.

It’s 12.00 and 00.00 so you are all wrong. ;)

Um, I think I said 00.

That is why intelligent people use the 24 hour scale.

^^^^ Intelligent people don’t need a prop like a 24 hour scale. We can handle an analog clock just fine!

The AM and PM things are props. We also use week numbers.

A 24 hour clock still has the same problem for 12:00. Is 12:00 am or pm? I assume that 00:00 would be am and maybe that would help people to use 12:00 pm.

@cazzie We also use week numbers.

Please explain. What is a “week number”? I don’t believe I have ever used one in the context of telling time or dates, only in the context of marking the x number of a sequence of y weeks.

@zenvelo
Intelligent people know how to simplify things for themselves.

week number (ukenummer) http://ukenummer.no/

@LostInParadise yes, 00.00 is am. Up to 23.59 is pm, then 00.00 is am, but we don’t write am or pm. There is no need, of course, when you use the actual hour and minute of the day.

The terms, ‘Mid-night’ and ‘Mid-day’ do seem rather self explanatory.

Thanks for the correction. That does make sense. It would also work for hours 1 to 24 instead of 0 to 23, but I think 0 to 23 makes more sense.

There is only one 12 in a 24 hour clock and it’s noon. The 24 hour clock has no confusion for any hour of the day. 6:00 is always in the morning and 18:00 is always in the evening.

But there’s no 24.

There is 00.