Why are There 60 Minutes in an Hour? | Hacker News Reader

Why are There 60 Minutes in an Hour?

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There is a book called "Civilization One" which talks about possible influences ancient cultures had on modern measurement systems. It's conclusions will probably be taken as a conspiracy theory by most but I found the book interesting nonetheless.

It actually goes into a theory of why the mathematics was the way it was (based on astrological observations rather than purely number of factors) which offers an interesting perspective on it all. The conclusion is largely that our measurement systems are deduced from our environment and that there is commonality between imperial and metric systems, both being derived well in the past.

I've been thinking about this for years now. I could never understand why no one had ever set 100 "minutes" to an hour.

I've thought about this too. Basically, once you switched, you'd obsolete a hell of a lot of stuff. For it to make sense, a large portion of the developed world would have to switch at the same time as you too. So unlikely to happen.

At the same time, I'm still trying to figure out why the USA doesn't strike imperial measurement from the books.

The US is a dual system-- people are free to use whatever system they want, but business is encouraged to use metric, especially for trade.

There was a big push in the 1970s to teach and adopt the metric system on a broad basis-- I remember there were even km speed limit signs-- but it failed. Americans think in feet, inches, miles, gallons, and pounds....imperial still has the first-mover advantage 400 years later!

Note that some things don't scale well. Cooking recipes are one example - all of the ratios matter and the mass/length ratios are different for metric than imperial. (Inches, for pans, and cups, for ingredients, have different relationships than centimeters and liters.)

Screw threads are another example. Metric threads have different characteristics than imperial ones.

Machinists also don't like the metric system much. There's no metric unit that's anywhere close to the mil (thousandth of an inch). So in fabrication work, you're forced to either use large, oddball numbers of micrometers, compromise your design by moving to 1/10 mm precision, or hose your budget by using micrometer-level precision.

64 would be more useful, and not too big a change.

Any tiny change when it comes to systems is huge. U.S. teaches but does not rely on the metric system for that reason.

What? 64 is only divisible by 2, 4, 8, 16, and 32. By contrast, 100 is divisible by 2, 4, 5, 10, 20, 25, and 50, while 60 is divisible by 2, 3, 4, 5, 6, 10, 12, 15, 20, and 30.

64 is only useful if you're writing numbers with binary digits. Since humans don't do that very often, day-to-day, I disagree with you that 64 is a good choice.

You're correct that 60 is more useful when dividing,

BUT:

Say we had 32 hours in a day, 64 minutes in an hour, 64 seconds in a minute... You could do date arithmetic simply. You could work out the number of seconds by simple bitshifts, rather than having to multiply and divide by 60/24.

My guess is that it's because you can divide sexagesimal time units into more useful fractions. That, in turn, might have simplified geartrain design in early timepieces.

100 = 2x2x5x5, while 60 = 2x2x5x3. A 100-minute hour would be divisible into twentieths, tenths, fifths, quarters, and halves, while a 60-minute hour would additionally be divisible by thirds, twelfths, and fifteenths.

Other than that, I got nothing. Somebody on time-nuts would likely know.

The sexagesimal system for times and angles was already in use in Mesopotamia circa 2000 BC. It's probably even older than that because it's so widespread and well-established in Eurasian cultures.

The "useful fraction" reason is the same reason that all the units for every kind of measurement used to be based on 12s, 24s, 60s, and 360s: angle, length, volume, weight, time, etc.

And not just in ancient times. It's much nicer to do graphic design on paper broken into whole numbers of inches, with those inches broken up in to 6 picas of 12 points each, than it is to design for A4 (or A3 etc.) paper, made of √2-multiples of base-10 metric units. It's much nicer (day-to-day) to describe triangles in terms of easy whole-number angles, instead of radians (now that we have more sophisticated math radians are great), and base-10 angles would be awful. It's much nicer to count off days of 12 hours, 60 minutes, 60 seconds than any base-10 alternative. Etc.

I think this article posted is completely missing the point. 12 wasn’t chosen because it could be made with a human hand; the particular way of counting on one hand was chosen because it matched the base-12/60 number system.

After the French Revolution, the Republic adopted a base-10 calendar. The number of months remained at 12, but a month's length was made uniform: each was divided into three weeks of 10 days.

The clock was modified accordingly: each day was divided into ten hours, each hour into 100 decimal minutes and each decimal minute had 100 decimal seconds.

The decimal clock was officially used in France in 1793-95. (I'd imagine that any remaining clocks from that era are highly valuable antiques nowadays.)

I've thought about a system like this... but the problem is, you can never get entirely base-10 because the Earth isn't so kind to us. It inconveniently revolves ~365 times for every time it circles the sun, so if you went entirely base-10 your 'days' wouldn't line up with actual daylight.

If you can't go entirely base-10, and only go halfway like the French... then it doesn't really buy you any convenience.

We could entirely ditch the notion that things have to line up and just go to stardates (or, well, something like that that actually makes sense).

Why would you prefer to keep Earth's revolution around the Sun as the base unit, instead of Earth's revolution around its axis? I would argue that the latter is more relevant for ordinary people. (Consider that Imperial Russia was using the fixed-365-day Julian calendar up to 1918, and they didn't seem to be acutely concerned that calendar months were drifting increasingly out of sync with actual seasons.)

I'd suggest adopting a 1000-day year instead. To make the transition easier, the word "year" could be deprecated entirely, and the unit of time would simply be called "kiloday" or "k-day". This proposal would significantly improve everyone's life by eliminating brainless smalltalk about whether it's particularly hot or cold this June compared to last year.

> I'd suggest adopting a 1000-day year instead. To make the transition easier, the word "year" could be deprecated entirely, and the unit of time would simply be called "kiloday" or "k-day". This proposal would significantly improve everyone's life by eliminating brainless smalltalk about whether it's particularly hot or cold this June compared to last year.

I bet you're fun at parties.

Whenever I'm at a party facing the choice of reorienting the conversation towards either the weather or calendar reform, I inevitably go for the latter. Chicks love it.

simply said, the Babylonian, first inventer has a base-60 and then will work with multiple of 60. In our era we have base 10, so we find it more easier to work with multiple of 10.

Interesting, I had no idea that Sumerians counted with there hands in this way. I've always counted like this because my parents and almost every Indian I know does as well.

I don't buy the cause and effect with regards to 360 degrees in a circle. If anything, 360 comes from the close approximation to 365, since pre-civilized humans would care more about the length of a year than divisibility. It's possible that the base-60 system was in fact back-ported from this more important and naturalistic number.

I do sometimes wonder if the people from ancient civilizations could see what we think about their writing and tools and culture, whether they would just laugh out loud. "No, no, that's just a spoon! And that little squiggle? That's a curse word, you idiots!"

Once when I visited a museum on a field trip, the curator explained that it was because the gene for 6 fingers was actually very common among Ancient egyptians, and so the use of base-6 and base-12 number systems became popular in astronomy and architecture. I haven't heard that since, however, and I'm not sure how true it is.

This museum wasn't in Kansas, was it?

Wouldn't you be able to count up to 72, not 60 with two hands?

12 from hand one + 12 * 5 from hand two = 72

maybe that's why a gross (144) was used. Or is it more like 12 x 12?

With 12 phalanges on each hand that can be marked by the thumb of the same hand, there are 12 possibilities on each hand, or 12 * 12 = 144 possible combinations of marked phalanges with two hands.

The article made it clear, both through the text and the picture, that only one hand used the phalanx counting method, while the other hand simply used digits as we do today. Thus, with 12 phalanges to choose from on one hand and 5 digits to choose from on the other, we have 12 * 5 = 60 combinations.

The very image and text used in the article implies that the original poster is correct.

Look at the example for 32 - it is given as 8 + 2x12. The hand on the right has two fingers extended. Clearly all fingers can be extended in this image, and then the number would be 8 + 5x12 = 68. If the left hand is used to count to 12, the number is 12 + 5x12, or 12+60=72.

Either the limit is 60, or the images/text in the article are wrong.

You're right! I didn't look closely enough. You can indeed symbolize 72 with the method shown in the picture.

Now that I finally get what viggity was saying however, I think that what you can count to with two hands wasn't what was significant -- it was that a full, open hand was worth 60.

You can't multiply the numbers because you couldn't depict prime numbers. For instance, what would you point at if you wanted to represent 13?

I wonder one thing: How Babylonian and Egyptian exchanged those informations and they use different languages and have different culture... This is more powerful than the Internet :D

Actually, I didn't read all that far because I was wondering why they would popup a facebook bar on the bottom.

Any reason for that? Do they get paid for it?

There is a great explanation of why Sumerians use 60 but I can't find the link.

In a nutshell the theory is: Sumerians counted each segment of their fingers using their thumb as a pointer (thumb segments were not counted) three segments per finger. They could do that five times using each finger as a holding place, so 3 * 4 = 12 * 5 = 60

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