It's only a coincidence if you ignore the fact that "digit" first and foremost refers to the things sticking out of your hands, and so was repurposed to talk about numbers because we have 10 digits on our hands.

That's the word's origin, not its current mathematical meaning. Also, number systems that are not base IIIIIIIIII have been used historically. That humans can only compute in a base that matches the number of fingers we have is a relatively recent myth.

Base-10 isn’t inelegant, is it? I mean there are good arguments for 12 being better but it isn’t like 10 is prime or anything.

Happened across a neat comment yesterday that presents a defense of ten. Not 100% convinced but it is interesting to see pushback.

https://news.ycombinator.com/item?id=39000882

Rational fractions will terminate only if the denominator’s prime factors are the base’s factors.

So for example, 1/2 = 0.5 and 1/5 = 0.2, but 1/3 = 0.333… and 1/7 = 0.142857….

1/4 = 0.25 works because the prime factors of 4 are 2 and 2… but 1/6 fails because 6 is infected by 3.

Now, base 12 has 2 prime factors (2 and 3) so it much any better than 10 really. But may I introduce base 30 (235)? Or perhaps base 210 will strike your fancy?

1+2+3+4=10

And you can swear by that, if you know what I mean.

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