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A slight tangent, but I recently ran across a fascinating theory on the origin of base-12 systems. If you use your thumb as a marker, you can touch four finger

A slight tangent, but I recently ran across a fascinating theory on the origin of base-12 systems. If you use your thumb as a marker, you can touch four finger joints on each hand for a total of 12 positions. I tried it and it's a surprisingly natural way of keeping count. Here's the source paper: http://www-groups.dcs.st-and.ac.uk/~history/HistTopics/Babylonian_numerals.html http://www-groups.dcs.st-and.ac.uk/~history/HistTopics/Babyl...

Dove 16y ago
Hmm. That is a very natural way to count quite high on your fingers. But it seems unlikely as the origin of the Babylonian system cited. The 60 symbols are written in base 10; if it grew out of a culture that counted to twelve on their fingers, I'd expect to see five groups of twelve, not six groups of ten. I can think of a more natural explanation. When I am counting something on my fingers (in the conventional way), I often want a way to store the tens digit. Perhaps the Babylonians did, too. That the tens digit is drawn as two groups of three is suggestive that whatever method they used stored a trinary and a binary state. So, when I count off (palms up), I get to ten on the thumb of my right hand. It has a little more dexterity than my other fingers and can store more states. It's pretty straightforward to get to six by leaving it bent/straight and pointing out/up/in. It's natural to do while counting, too. (Bent and pointing in is a little uncomfortable if I want to use the other fingers, but then . . . you don't ever need to actually store 'six').
caf 16y ago
If you use the tip of each finger as well, you can count in hex to 0xff with two hands ;)
- what 16y ago
  You can count to 1023 in binary using both hands.
eitally 16y ago
Anecdotal evidence of real life application: my mother (Indian/Pakistani, born in the '40s) counts this way. I never asked, but presumably she was either taught by her parents or in school.

Dove 16y ago

Hmm. That is a very natural way to count quite high on your fingers. But it seems unlikely as the origin of the Babylonian system cited. The 60 symbols are written in base 10; if it grew out of a culture that counted to twelve on their fingers, I'd expect to see five groups of twelve, not six groups of ten. I can think of a more natural explanation. When I am counting something on my fingers (in the conventional way), I often want a way to store the tens digit. Perhaps the Babylonians did, too. That the tens digit is drawn as two groups of three is suggestive that whatever method they used stored a trinary and a binary state. So, when I count off (palms up), I get to ten on the thumb of my right hand. It has a little more dexterity than my other fingers and can store more states. It's pretty straightforward to get to six by leaving it bent/straight and pointing out/up/in. It's natural to do while counting, too. (Bent and pointing in is a little uncomfortable if I want to use the other fingers, but then . . . you don't ever need to actually store 'six').

caf 16y ago

If you use the tip of each finger as well, you can count in hex to 0xff with two hands ;)

what 16y ago
You can count to 1023 in binary using both hands.

eitally 16y ago

Anecdotal evidence of real life application: my mother (Indian/Pakistani, born in the '40s) counts this way. I never asked, but presumably she was either taught by her parents or in school.