I’ve never understood the 12 hour clock. Like, you just decide to reset the time at lunchtime or something? Why not have an 8 hour clock and reset the time after breakfast and just before teatime, it makes just as much sense
In ancient times, people did not have the concept of a “civil day”; they viewed day and night as separate things which alternated.
The Assyrians divided the day into six equal parts, and the night into six equal parts, called ush. But because sunrise and sunset move around over the course of the year, the lengths of day and night vary, and thus one ush during the day would not be the same length as an ush at night except around the equinoxes.
The Babylonians divided ushes in two to make hours, because it was easier to do astronomy in 12s than 6es. This resulted in 12 hours in a day and 12 hours at night, but daytime hours were still different lengths to nighttime hours, and the lengths of hours still varied over the course of the year.
The Greeks partially adopted the Babylonian system; they divided the day into 12 hours but the night was divided into four watches. The Romans copied the Greek system, but later went full Babylonian with 12 hours at night as well. (I feel like this coïncided with the rise of Christianity, but I have no evidence). The Romans introduced the concept of the civil day beginning at midnight (which the Chinese independently came up with), and over time, this led to the idea of 12 hours from midnight to noon, and 12 hours from noon to midnight. That idea postdates Rome, however; Roman hours were reckoned from sunrise to sunset and sunset to sunrise.
Assyrian astronomical knowledge seems to have reached China via India, as traditional Chinese timekeeping divides the civil day into 12 shi. Ancient shi were like Assyrian ushes; they were either 1/6 of a day or 1/6 of a night. Originally, midnight and noon fell in the middle of a shi, but this was changed to shi starting at midnight to make administration and astronomy easier. This system of variable-length shi continued to be used in Japan until about the Meiji Restoration.
Fixed-length hours are the result of analogue clocks, which are impractical to design to change the lengths of hours with the seasons (but not impossible; the wskusei clock is an ingenious Japanese clock from the 17th century that does exactly that). China had reliable, accurate water clocks by the Tang dynasty, while Europeans developed circular mechsnical clocks in the late Middle Ages. In neither case was it practical to make something as clever as the wakusei clock, so analogue clocks were marked the mean length of a shi or an hour as a reasonable approximation. Since there are 12 hours from midnight to noon and 12 from noon to midnight, that led to the 12-hour time system we know today.
Well, time measurement and the division of the day into 12/24 hours is of course entirely a human concept and thus a bit arbitrary and made up, so yes, you could divise a system with 8 hour splits, sure.
But the 12-hour system makes sense as soon as you buy into the 1 hour = 60 minutes convention and split that up into 5-minute blocks. There are 12*5minutes in an hour, so after 12 hours your hour and minute hand reach the same position again, thus the reset.
That doesn’t work so well with 8 hours, because you’d have to divide the hour into 60/8=7.5 minute blocks, which is pretty awkward.
Or you’d have to define the hour as having 64 minutes and divide it into 8*8 minutes blocks. And theres a dualist religion in my favorite fantasy RPG world, that would award you sainthood if you did that, but that’s not the world we live in.
I’ve never understood the 12 hour clock. Like, you just decide to reset the time at lunchtime or something? Why not have an 8 hour clock and reset the time after breakfast and just before teatime, it makes just as much sense
In ancient times, people did not have the concept of a “civil day”; they viewed day and night as separate things which alternated.
The Assyrians divided the day into six equal parts, and the night into six equal parts, called ush. But because sunrise and sunset move around over the course of the year, the lengths of day and night vary, and thus one ush during the day would not be the same length as an ush at night except around the equinoxes.
The Babylonians divided ushes in two to make hours, because it was easier to do astronomy in 12s than 6es. This resulted in 12 hours in a day and 12 hours at night, but daytime hours were still different lengths to nighttime hours, and the lengths of hours still varied over the course of the year.
The Greeks partially adopted the Babylonian system; they divided the day into 12 hours but the night was divided into four watches. The Romans copied the Greek system, but later went full Babylonian with 12 hours at night as well. (I feel like this coïncided with the rise of Christianity, but I have no evidence). The Romans introduced the concept of the civil day beginning at midnight (which the Chinese independently came up with), and over time, this led to the idea of 12 hours from midnight to noon, and 12 hours from noon to midnight. That idea postdates Rome, however; Roman hours were reckoned from sunrise to sunset and sunset to sunrise.
Assyrian astronomical knowledge seems to have reached China via India, as traditional Chinese timekeeping divides the civil day into 12 shi. Ancient shi were like Assyrian ushes; they were either 1/6 of a day or 1/6 of a night. Originally, midnight and noon fell in the middle of a shi, but this was changed to shi starting at midnight to make administration and astronomy easier. This system of variable-length shi continued to be used in Japan until about the Meiji Restoration.
Fixed-length hours are the result of analogue clocks, which are impractical to design to change the lengths of hours with the seasons (but not impossible; the wskusei clock is an ingenious Japanese clock from the 17th century that does exactly that). China had reliable, accurate water clocks by the Tang dynasty, while Europeans developed circular mechsnical clocks in the late Middle Ages. In neither case was it practical to make something as clever as the wakusei clock, so analogue clocks were marked the mean length of a shi or an hour as a reasonable approximation. Since there are 12 hours from midnight to noon and 12 from noon to midnight, that led to the 12-hour time system we know today.
You’ve never seen an analog clock?
That’s where it comes from, and that’s where it makes perfect sense. (An 8 hour reset wouldn’t) No need to carry that over to digital clocks however.
You have it backwards. Analogue clocks are the way they are because of the 12-hour convention.
Why wouldn’t an 8-hour reset make sense? Just have 8 numbers instead of 12 and spin the hour hand a little faster.
A 12-hour analogue clock barely makes sense anyway. Mine’s 24.
Well, time measurement and the division of the day into 12/24 hours is of course entirely a human concept and thus a bit arbitrary and made up, so yes, you could divise a system with 8 hour splits, sure.
But the 12-hour system makes sense as soon as you buy into the 1 hour = 60 minutes convention and split that up into 5-minute blocks. There are 12*5minutes in an hour, so after 12 hours your hour and minute hand reach the same position again, thus the reset.
That doesn’t work so well with 8 hours, because you’d have to divide the hour into 60/8=7.5 minute blocks, which is pretty awkward.
Or you’d have to define the hour as having 64 minutes and divide it into 8*8 minutes blocks. And theres a dualist religion in my favorite fantasy RPG world, that would award you sainthood if you did that, but that’s not the world we live in.
Damn, this person knows clocks
I understand the thrust of your argument, but I respectfully disagree.
Someone made the call to choose a division of 12 though. They could have also chosen 24.
And have the numbers spaced 2.5 minutes apart?! MADNESS!