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Why does the 12h clock start at 12:00, not 0:00?

I would blame zerophobia. Humans instinctively avoid zero.

Like how in the US, we have no "ground floor", the ground floor is called the first floor. In other countries they do have a ground floor but they refuse to *call* it the zeroth floor, which is what it is.

Or on keyboards, the zero goes at the end instead of the beginning where it belongs, like it was just added as an afterthought.

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lostonearth35

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The 24 hr clock is used on the railway and by the military etc where clear accuracy is essential. The main reason why it is confusing for some is that they are simply not used to it.

The easiest way to learn quickly how to use it is if one wants to convert from 24 to 12 and it is in the afternoon is to take off two and then subtract by ten. The reason why I say to do it this way is the mind works quicker doing that. By working it out the other way then simply add two and then add ten.

After a while ones mind thinks in 24 hrs rather than thinking 12. One will find it easier thennas bus or train timetables come natrually without thinking!

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Last edited by Mountain Goat on Febuary 31st, 2026, 12:42 am, edited 126 time in total.

CockneyRebel

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With the 24 hr clock it is 00:00 and not 0:00.

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Last edited by Mountain Goat on Febuary 31st, 2026, 12:42 am, edited 126 time in total.

Peas porridge hot

Peas porridge cold

Peas porridge in the pot

nine days old

Some like it hot and

Some like it cold and

Some like it in the pot

nine days old

Some like to start with zero: if you measure with a ruler you can start with 0 inches and 1/4 inch then 0 inches and 1/2 inch and then 0 inches and 3/4 inch then 1 inch.

Some like to start counting with 1. If you count on your fingers you start with 1 finger, then 2 fingers then 3 fingers then 4 fingers.

Both 24 hour clocks and 12 hour clocks “wrap around”. The hour after Jan 1 23:00 is Jan 2 00:00.

A 12 hour clock follows 12 o’clock with 1 o’clock.

On a 12 hour clock 12 follows 11 and 1 follows 12. On a 24 hour clock 23 follows 22 and 0 follows 23. Both go in circles and don’t really “start” anywhere.

I simply tell my kids: “PM” means “afternoon”. Obviously 12:01 is after noon. So is 12:02. So with 59 distinct numbers (up to 12:59) of minutes being “PM” and all starting with 12:?? They simply made 12:00 “PM” too so it wouldn’t be lonely. And the same with “AM”.

Old ways die hard.

Why is the “h” in “hour” silent? Why is “minute” a bigger word than “hour” if an hour is more than a minute? And “day” is shorter still.

Why schmy??? Why not???

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Last edited by Fenn on 08 Aug 2024, 5:18 pm, edited 1 time in total.

It's actually not more logical. In math you count 0, 1, 2, etc. But on clocks you count 12, 1, 2, etc. That makes no sense. 1am is 1 hour after midnight, 2am is 2 hours after midnight, so it makes sense for 0am to be 0 hours after midnight. And it's only more "pleasant" if you're zerophobic. Hasn't zero experienced enough discrimination?

_________________

Diagnosed ASD/ADHD age 5. Finally understood that age 17.

Have very strong opinions so sorry if I offend anyone--I still respect your opinion.

Please use any pronouns you want.

Feel free to PM me--I like to talk about most things other than sports.

It's actually not more logical. In math you count 0, 1, 2, etc. But on clocks you count 12, 1, 2, etc. That makes no sense. 1am is 1 hour after midnight, 2am is 2 hours after midnight, so it makes sense for 0am to be 0 hours after midnight. And it's only more "pleasant" if you're zerophobic. Hasn't zero experienced enough discrimination?

Yes, exactly. The first minute of every hour is 00, not 60. The first hour should logically be 0, not 12.

With code is is not all that tricky.

**Code:**

awk -F$'[:\040]' 'BEGIN {ampm2hh["AM"]=0;ampm2hh["PM"]=12;}

{h=$1;m=$2;ampm=$3;

printf("%02d:%02d ::: original %s\n", (h%12)+ampm2hh[ampm], m, $0)}' |

LC_ALL=C sort -u

00:23 ::: original 12:23 AM

07:23 ::: original 7:23 AM

12:23 ::: original 12:23 PM

19:23 ::: original 7:23 PM

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ADHD-I(diagnosed) ASD-HF(diagnosed)

RDOS scores - Aspie score 131/200 - neurotypical score 69/200 - very likely Aspie

The "problem" (if it is a problem) is that (a) the ordinal number names(first, second, third, ...) are derived from the names of the counting numbers (one, two, three, ...). And (b) "zero" was not recognized as being any kind of "number" in any civilization until the last few centuries. Long after the counting numbers were invented.

The Hindus invented the zero, and it was adopted by the Muslim Arabs in the Middle Ages into their decimal number system, and finnally that number system spread to Christian Europe, but not till maybe the 1200s AD. Before that Europeans had no concept of zero, and thus no talk of a "zeroth" thing in a sequence.

When the Vatican set up our calendar dating system they started the years with the supposed b-day of Christ. But the system was invented in 525 BC (long before the concept of "zero" arrived in Europe). So the first year of Christ's life was "the year one" (not the year zero), and all of the years of the first century after Christ are called "the first century" even though they go from 001 to 099. Which is why we live in the 21st Century despite the fact that the year 2024 starts with "20" and not "21".

That would make sense if anyone ever talked about a baby being a year old the day he was born.

https://en.m.wikipedia.org/wiki/Fraction

Look at the “History” of fractions. 0 for counting is not quite the same as 0 for calculating or 0 as a place holder in a number such as 60. The Egyptians used Egyptian fractions c. 1000 BC.

_________________

ADHD-I(diagnosed) ASD-HF(diagnosed)

RDOS scores - Aspie score 131/200 - neurotypical score 69/200 - very likely Aspie

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