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Comment by spiffytech | Hacker News Reader

> a bit like using the number of fingers we have to argue that decimal is the best number system to work in.

Fun fact unrelated to your main point: some ancient peoples counted on their knuckles, using their thumb to point to each one. This let them count in multiples of 12 (3 knuckles on each of 4 fingers), then use their other hand to count out multiples! You can count as high as 72 this way, which was great for ancient cultures oriented around highly composite numbers like 12, 24, and 60.

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I like to believe this is true because it makes sense, but it was a theory invented in the 20th century to try to explain how they did math in everyday settings. We don’t actually know if it is true. We just know that they used base-60 systems.

Yeah, 60 was likely used because it divides by 2,3,4,5,6 and 10, 12 and 15. I imagine it makes dealing with fractions much easier.

Oh, good to know!

> some ancient peoples counted on their knuckles, using their thumb to point to each one.

I don’t know how “ancient” you’re talking about: my mother (b. 1937) used such a system and taught it to us as kids. FWIW she grew up in south east Asia.

Can’t you count as high as 156?

12 knuckles/finger segments, incrementing by 1 on the left hand for each completed counting of 12 on the right = 12 * 12 + 12 = 144 + 12

I may have misunderstood the proposed counting method however.

I was wondering, can't you count to 144 (12 x 12) using two hands using this knuckle counting approach?

Or 169 (13 x 13).

I mean, even without knuckles you have 10 bits to play with. If you also curl your toes, that's 12 bits. So an average person could count to 4095.

I actually figured out how to count up in binary on my fingers and you can get way higher if you use your thumbs for the lowest two bits, and bent fingers as bits differentiated from a fully extended finger. All the way to 262,143.

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