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by elbows 2601 days ago
I use am/pm because that's how I was taught to tell time growing up, and in my corner of the world (northeast US) nearly everyone uses it. "2 pm" is immediately meaningful to me, but to parse "14:00" I have to subtract 12 in my head. Even when the am/pm is left off, it's usually clear from context.

I'm not arguing for the inherent superiority of am/pm notation, but I do get frustrated with people who use 24-hour time because "it's more logical", without seeming to realize that it's more difficult for the majority of people to understand.

4 comments

> majority of people to understand.

Depends where / with who you work? Most of my colleagues have to think the same way about am / pm and often get it wrong when it's 12:00 am/pm.

The 'it's more logical' for me does apply there; in the 24:00 you cannot get 12:00 or 00:00 wrong no matter how you think about it. It feels intuitive in every way.

12 hour clocks made sense when clocks had 12 hours on them; then you had to somehow indicate which block of 12 hours; that problem was fixed before I (and probably you) were born though.

I grew up with 24-hour clocks, and I always get confused by the 12h version of midday and midnight.

Literally, the mnemonic I use to remember which is which is "it's the one that doesn't make sense".

So 11am then 12pm

And 11pm then 12am

(Whereas I would expect the 12th hour of the morning to follow the 11th of the morning, but it's actually the other way around)

You don't subtract it though. Once you are used to it your brain just correlates 14 with 2 and 17 with 5 and 23 with 11 without thinking. In Norway, and I think in most of the 24-hour world, we still use the 12hr clock in speech. I don't go around saying that "the clock is quarter past fifteen", I say "quarter past three" and the context usually makes it clear when I'm talking about.
Indeed. It is written 15:15, but pronounced three-fifteen (or quarter past three etc.).
Same in Germany
This is exactly the same defence people have about the imperial system. (I'm british so have the 'benefit' of having both systems existing in my head as a weird mish-mash).

I can take it as a "con" against any new system, but it doesn't outweigh all other benefits- if it did then there'd be no progression in society -ever-

do people actually say "fourteen oh-oh"?

I've used 24 hour clocks all my life and everyone uses 1-12 when talking. If someone is coming to see you at 14:00 they will say: "see you at two". We only use the proper format when writing.

No, in speech/direct chat you would say 2 indeed, but not when it can be confusing. When there is any doubt, even on the phone when making an appointment I always repeat the time in 24 hour format if the appointment is more than 12 hours away. Just to make sure.
I wouldn't say "fourteen oh-oh", but "fourteen hundred", and I've rarely heard just "fourteen".

Extends obviously to "fourteen thirty".

(Northern England)

Interesting, I thought that -hundred or even -oh-oh was an American thing, originating in their military. (Non-native speaker from the continent.)