Gregory's Server@nikitonsky Ancient Near Eastern cultures counted to 12 on one hand by moving the thumb along the pattern of red numbers I’ve added to this image. To count higher, they’d add 12/finger on the other hand, which got them to 60 using both hands. Mesopotamian mathematicians codified this into a base-60 number system, which is why we have 60 minutes/60 seconds/360º (6 x 60), &c. (The one-handed 12 is also why the first Egyptian sundials had twelve divisions, so we have 12 hours/day.)
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 @nikitonsky They *could* have counted many ways — to 9999 on two hands like this image from the 1400s, for example — but this is how they did it. 360: they did maths differently (all fractions, division via multiplication by reciprocal, &c) using pre-computed tables and a “squared circle” approach for trig-ish things (no angles!). 360 was both precise enough for surveying and easy to use with their system. There’s also an Egyptian astronomy tie-in, but that’s another story… |
@jack Could’ve counted up to 144 though
But wait, where does 6 from 60*6 comes from?