Thought of this in the shower this morning, if anyone has an answer I’d be very interested!

I think it’s because there are important, naturally occuring units of time that simply don’t divide well - that is, the day and the year. Having it standardized to metric would still leave us with 1:365.24 conversion. Using metric time would require us to stop being metric beyond the day, or just have a cumbersome conversion number to talk about years.

On the other hand, things like weight, length, and temperature are completely arbitrary and there’s no natural standard unit, so changing those to another completely arbitrary unit is easy.

While it would he handy to have everything integrated, it’s not always vital. We don’t need to convert kilograms to seconds very often. Artificially enforced systems have always had trouble replacing older anachronistic ones that are otherwise still useful. Ask people in the UK about their cars’ efficiency and you’ll often get an answer in miles per gallon.

There’s nothing magical about 10, either, other than the accidents of evolution that left us with ten fingers. Base 12 is also extremely convenient, and comes from Sumerians counting with their thumb against each of the three joints on 4 fingers. Go through that process once for each finger on the other hand, and you get 60. And of course, in any industry where things are packed into packages, like nearly everything we buy, dozens fit better than tens. 60 divides very neatly into many convenient and geometrically simple fractions, and a lot of what we do with circles benefits from this.

We probably would have been better standardizing on a base unit that’s a power of two, which has more mathematical weight than ten does.

12 and 60 divide nicely. A quarter of a 12-hour clock is 3 hours, but in decimal time it’d be 2.5 hours. A third is 4 hours in base 12, but some gross 3.33 repeating in decimal.

I just don’t like it.

That’s the same argument for (some) Imperial measurements, but people converted to metric anyways.

Metric isn’t better because it uses 10, it’s better because it uses the same base for everything. A measurement system (and number system) that uses 12 for everything would be better than both imperial and metric.

The short answer to why we use it is that we inherited it - base 12 of hours/months from the Egyptians and base 60 of second and minutes from Mesopotamians (who got it from the Sumerians).

Egyptians used base 12 a lot for a similar reason that we use base 10 a lot. We use 10 because we have ten fingers, and they used 12 because one hand has 12 knuckles (they’d count on one hand). But it was handy because there are 12 lunar cycles, so it helped keep things more consistent.

Base 60 is also handy because 60 is first number divisible by the first six counting numbers and by 10, 12, 15, 20 and 30. If you use 60, you have options! Note that we also use 60 for angles and dividing up the globe.

Yep. Your four fingers have three knuckles each. You count along them with your thumb. Then each count of 12 is counted with an extended finger on your other hand. Extend all five fingers and you have 60.

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