zompist wrote: ↑Fri Aug 16, 2019 11:54 pm
TomHChappell wrote: ↑Fri Aug 16, 2019 10:04 pm
I never heard of a natlang with base two,
Well, there's quite a few languages which we can call, neutrally, 2-centric. The pattern tends to be
[1]
[2]
[2] [1]
[2] [2]
[2][2][1]
[2][2][2]
...
Now, this isn't how we expect a binary system to work based on computer notation. But it is if we accept that [2][2] is the word for four!
After all, we don't insist that English isn't decimal because the PIE word 'hundred' is etymologically 'ten-(something)'. (Where the 'something' is unknown.)
I think that's cheating a little - there's a difference between the etymology of a word and its synchronic meaning. So intuitively there's a difference between a phrase synchronically meaning 'two plus two' and a word that merely etymologically meant 'two plus two' once upon a time. Also, 'hundred', even diachronically, is still multiplicative, unless the 'something' meant 'ninety'...
I think there is a valid distinction to draw between what Tom calls additive, multiplicative and exponential bases, although I've no idea if, or with what terminology, it's drawn in the literature.
Here's a rough attempt at a formula for counting: numbers within the range
k are expressed with the formula
awf + bxg + cyh ...
The 'standard' decimal is produced when, for all k, w=10, x=10, y=10, etc, and f,g,h etc equal 1, 2, 3 etc, and a,b,c etc are all <10.
If you make a, b, c etc all equal either 1 or 0, and f,g,h etc all equal 1 or 0, then you have an 'additive' system.
If you allow a,b,c etc to not always equal either 1 or 0, but f,g,h etc all equal 1 or 0, then you have a 'multiplicative' system.
If you allow not only a,b,c but also f,g,h to not equal 1 or 0, then you have an 'exponential' system.
So if we take the numbers 4, 44 and 214, and assume that w=x=y=10, and a,b,c etc are all <10:
- in a pure additive system these are [4], [10+10+10+10+4], and [10+10+10+10+10+10+10+10+10+10+10+10+10+10+10+10+10+10+10+10+10+4]
- in a pure multiplicative system these are [4], [10x4 + 4] and [10x10 + 10x10 + (1x)10 + 4]
- in a pure exponential system these are [4], [10x4 +4] and [2x10^2 + (1x)10^1 + 4]
All of these systems can in some sense be called 'decimal', 'base ten' or 'ten-centred' or the like, but are very different. Only the exponential system is what we might more properly call 'radix 10', or decimal in the narrow sense.
Normally, w=x=y (etc); otherwise, you have a mixed base system. For instance, in a 10:60 multiplicative system, 214 would be [3x60 + 3x10 + 4].
Mixed base systems also enable systems in which a,b,c etc are all =< 1, but f,g,h aren't. For instance, 214 could be expressed as [5^3 + 2^3 + 7^2 + 5^2 + 7^1] (where x,y,z are primes under 10). I doubt any human language uses such a system, though.
It's also notably possible to have what we might call a 'mixed regime' system, in which the parameters of the formula change depending on
k. For instance, a system might be additive base 10 up to 20, but then multiplicative base 5 above 20. So 18 would be [10 + 8], but 28 would be [5x5 + 3].
Interesting thigns can then also happen with a, b, c etc. In standard exponential decimal, each of these must be < 10, which is convenently =x. But you could also have systems where a,b,c can be greater than x. Tolkien's hobbits have such a system, in which 110 is [11x10] (eleventy-ten) - that is, their a,b,c are <12, even though their x,y,z are 10.
In such a system, there are multiple ways to express a number, and there may or may not be rules to say which is preferred - larger 'big end' (higher powers) or large 'small end' (lower powers) numbers. So 111 could be in one system [11x10 + 1] (maximising the big end) or in another [10x10 + 11] (maximising the small end). Or in some systems there may be a choice.
Similarly, when a,b,c < x,y,z, you likewise get a choice. So 28 could be [5x5 + 3], or [4x5 + 8] (big end vs small end).
We could even imagine some insane language in which:
- for k < 13, there is no base (each number is non-decomposable)
- for 12 < k < 80, there is multiplicative base 10
- for 79 < k 100, there is a multiplicative mixed base where x=10 and y=20, with priority to the highest multiple of y
- for 99 < k < 180, there is multiplicative base 10
- for 179 < k < 200, there is a mixed base again, and so on.
But surely such a system would never catch on...
Finally, there can also be cases where a,b,c etc may themselves be products. This is only really an etymological quirk with exponential system, but it provides an interesting variation to multiplicative systems. So, while a normal multiplicative system may have 210 as [10x10 + 10x10 + 10] or (if a < 21 even though x=10) [20x10 + 10], a product system could have [3x7x10].
So far as I know, all such systems are used only for small numbers by our standards. On the other hand, such systems are what make me dubious about claims that certain people "can't count above two". The commonness of the above system makes me think that many "one, two" systems are really extensible the same way, only the original researchers didn't realize it because they were only expecting to find a word "three".
Pratchett's trolls are derided for being unable to count to three - they just count 'one, two, many'.
This is because humans don't bother listening beyond that point. How the trolls actually count is "one, two, many, many-one, many-two, many-many, many-many-one, many-many-two, many-many-many, lots!" [that is, they have an additive system where x is 1, 2, 3 or 10. This is notably different from a mixed radix multiplicative or exponential system with bases of 3 and 10, because the former would give 'two-many' (for 4) and 'many-many' (for 9), while the latter would give 'two-many' and 'many-cubed'...]