Quaternary is a power of 2 base, and so is pretty closely related to binary. Each quaternary digit corresponds to a group of 2 binary bits, so you can easily convert. For example 100011 -> 10,00,11 -> 2,0,3 -> 203. Computer science uses hexadecimal for essentially the same reason (just grouping bits by 4 rather than 2), so people from this culture might be better with computers.
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Hmm. Maybe they were experts at some precursor to quantum physics, and viewed nature itself as 0s and 1s?
That binary conversion made absolutely no sense at all to me, so I'll research it now!
Edit: OK, it's pretty easy once you know how binary progresses. I think this micro-science binary theory might have legs. Thanks for the suggestion!
Why did you choose quaternary in the first place? Do they have four fingers on each hand or something? Dozenal is good for times tables, binary is useful for simplicity, hexadecimal is useful for compactly dealing with binary. Decimal doesn't have much going for it except that we can count on our fingers, so I could image quaternary being a similar concept.
I chose quaternary because you have to use decimal for time, weeks, months etc, because it would be a pain in the ass to have to convert everything all the time. So the quaternary system is the "ancient" system they used long ago. But in truth, it's so I don't have to come up with so many names for different numbers haha. I only needed a system that goes to 16 (decimal) so quaternary is a perfect fit in that regard. An example of it in use: the word for rainbow is d'ci'ka. It's a contraction of denci' ("ten-three", or 7) + kaza (color) Thirteen colors. Same process for the word weekend, which is d'ci'mw. Denci' + mw ("one"). 7/1. The 7th and 1st days of the week.