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Ask HN: What does 12:00 AM mean?

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Re: Ask HN: What does 12:00 AM mean?

#211

Years ago I missed a night international flight because of this. It left at 12:00 am (midnight) Nov.10, but to me that meant at the end of the day so I show up 3 hours early at 9pm on Nov.10, only to find out the flight left 21 hours ago. I should have arrived 9pm Nov.9 to catch the plane at 12:00am which technically was the very start of Nov.10. I've noticed that they no longer post 12:00am as a flight time. Instead…

Sorry to hear that. It’s much worse than my missed exam.

Re: Ask HN: What does 12:00 AM mean?

#212

Earlier quoted context omitted.

> We know when the new _day_ starts because the date rolls over at that time. That's an additional reasoning you have to do in order to explain the non-intuitive fact that the new day starts when transitioning between hour 11 and 12. You can't come up with that conclusion based on clock system alone, you need to reach for the calendar. It makes you jump additional mental hoops, making it error prone (as evidenced by…

Well, some of them sound more convincing than the others. Intuitively, "12:30 AM" (whose meaning is unambiguous) seems to have more affinity to 12:00 than 11:30 PM does. But since the midnight is the same distance from the noon, before (AM) or after (PM), in theory both should be reserved for midnights (the past one and the future one), and noon, too, should be both AM and PM - at 0 hours. The only real solution for…

There's a much better solution used by a huge chunk of the world already - the 24 hour system, which avoids these pitfalls completely. "Burning the meaning into your brain" is just destined to fail when you use the 12 hour system rarely enough, like a lot of people do.

Re: Ask HN: What does 12:00 AM mean?

#213
post #205

A classic problem similar to this would be a flight. If you got a flight departing at 12:40am, make sure you really know what it means. There’s too many people making this mistakes and sometimes the airline might help you out but not always.

That's a good point, but 12:40am is a very unusual flight time? That's almost 1am. I would guess most flights are in the ballpark of 7am - 9pm. Please correct me if I'm wrong.

I personally have taken flights with weird departure time like this. A lot of flights from San Francisco to Hong Kong has departure time like this, arriving Hong Kong at around 7am.

I think in general it is just depends on the origin+destination time zone & fight duration, these 2 factors determines the sweet spots of departing, and while there can be a few combinations that works, those few combinations can likely be realized due to various factors.

Other examples involved going from Hong Kong to London (which has similar relation comparing to going from SFO to HKG). I personally didn’t try that but first heard people made mistake like this (getting to the flight one day late) in this combination.

Re: Ask HN: What does 12:00 AM mean?

#214

It reminds me of a similar problem I face in Dutch (and still trip up if I'm not conscious): In Dutch (my 4th language), "half nine" ("half negen") means 8:30 . Whereas in English[1] "half nine" means 9:30 . So there were times when I missed appointments by an hour! After 7 years of being immersed in the language, I still have to deliberately engage my brain whenever someone says "half nine" (or whatever the hour) in…

there is same issue in Slovak/Czech vs English, which is very confusing with my kid which was raised at first in English and later we added Czech

English is quite logical - half PAST nine = 9:30, but in Czech/Slovak you say literally "at quarter on ten" (9:15), "at half of ten" (9:30), "at three quarters on ten" (9:45) and that "on" ain't really obvious for someone who is not familiar with this terminology, personally I completely stopped using this terminology because I always found it archaic and extremely confusing and just use digits "nine fifteen", "nine thirty" etc.

same goes for fractions vs percentages, I don't understand media love for fractions, instead simply writing 60% they write three fifts, so I have to calculate it in my mind back to 60 to know what they are talking about instead if they used one simple digit

Re: Ask HN: What does 12:00 AM mean?

#215

It reminds me of a similar problem I face in Dutch (and still trip up if I'm not conscious): In Dutch (my 4th language), "half nine" ("half negen") means 8:30 . Whereas in English[1] "half nine" means 9:30 . So there were times when I missed appointments by an hour! After 7 years of being immersed in the language, I still have to deliberately engage my brain whenever someone says "half nine" (or whatever the hour) in…

there is same issue in Slovak/Czech vs English, which is very confusing with my kid which was raised at first in English and later we added Czech English is quite logical - half PAST nine = 9:30, but in Czech/Slovak you say literally "at quarter on ten" (9:15), "at half of ten" (9:30), "at three quarters on ten" (9:45) and that "on" ain't really obvious for someone who is not familiar with this terminology, personall…

Wow, "at quarter on ten" / "at half of ten" takes even more brain cycles for me to parse. Thanks for the Slovak/Czech examples. (Incidentally, I work with a lot of Czech colleagues.)

Re: Ask HN: What does 12:00 AM mean?

#216

It reminds me of a similar problem I face in Dutch (and still trip up if I'm not conscious): In Dutch (my 4th language), "half nine" ("half negen") means 8:30 . Whereas in English[1] "half nine" means 9:30 . So there were times when I missed appointments by an hour! After 7 years of being immersed in the language, I still have to deliberately engage my brain whenever someone says "half nine" (or whatever the hour) in…

there is same issue in Slovak/Czech vs English, which is very confusing with my kid which was raised at first in English and later we added Czech English is quite logical - half PAST nine = 9:30, but in Czech/Slovak you say literally "at quarter on ten" (9:15), "at half of ten" (9:30), "at three quarters on ten" (9:45) and that "on" ain't really obvious for someone who is not familiar with this terminology, personall…

> "at three quarters on ten"

What a mouthful. Can I ask you to write how it is written and spelled out?

Re: Ask HN: What does 12:00 AM mean?

#217

Earlier quoted context omitted.

there is same issue in Slovak/Czech vs English, which is very confusing with my kid which was raised at first in English and later we added Czech English is quite logical - half PAST nine = 9:30, but in Czech/Slovak you say literally "at quarter on ten" (9:15), "at half of ten" (9:30), "at three quarters on ten" (9:45) and that "on" ain't really obvious for someone who is not familiar with this terminology, personall…

> "at three quarters on ten" What a mouthful. Can I ask you to write how it is written and spelled out?

https://slideplayer.cz/slide/12864735/78/images/5/Pozn%C3%A1...

Here in Czech, learning materials for 2nd grade, though my kid is learning it already in 1st grade.

Re: Ask HN: What does 12:00 AM mean?

#218

Earlier quoted context omitted.

there is same issue in Slovak/Czech vs English, which is very confusing with my kid which was raised at first in English and later we added Czech English is quite logical - half PAST nine = 9:30, but in Czech/Slovak you say literally "at quarter on ten" (9:15), "at half of ten" (9:30), "at three quarters on ten" (9:45) and that "on" ain't really obvious for someone who is not familiar with this terminology, personall…

Wow, "at quarter on ten" / "at half of ten" takes even more brain cycles for me to parse. Thanks for the Slovak/Czech examples. (Incidentally, I work with a lot of Czech colleagues.)

Yeah, it makes really no sense even for native speaker when you think about it, people just accept this nonsense, in English it's either how many minutes past some time, or how many minutes to next hour, but in Czech/Slovak you talk "on hour", not sure what's origin of this nonsense, but I doubt majority of people could explain the meaning.

We also commonly use double negative:

English - I did nothing

Slovak/Czech - I didn't do nothing (reverse I did everything)

People don't think about it, just accept this nonsense and go on with it.

Czech language has even way more illogical things than Slovak, since it is older, for instance they have special letter ů which sounds exactly same as ú (as oo in Doom), but ů can't be used as first letter of word, where you must use ú and vice versa, if it's not first letter must use ů and can't use ú, despite both of them having exactly same meaning/sound.

Re: Ask HN: What does 12:00 AM mean?

#219

Earlier quoted context omitted.

> "at three quarters on ten" What a mouthful. Can I ask you to write how it is written and spelled out?

https://slideplayer.cz/slide/12864735/78/images/5/Pozn%C3%A1... Here in Czech, learning materials for 2nd grade, though my kid is learning it already in 1st grade.

Ah, as I though it's just rolls fine in the spoken language. "Tr/ee/chetvert" should be a good enough approximation, I suppose?
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