Goodbye RISC, hello OIC: One Instruction Computer.
Mathematics
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Those already exist: https://en.wikipedia.org/wiki/One-instruction_set_computer
Yeah, I at first misunderstood that Not-AND was being used as an analogy for Exp-Minus-Log.
this one weird trick :)
I can kinda see how to get pi (and most of trig in general), the imaginary unit, and even some calculus, but (weirdly) basic arithmetic seems to be more difficult. I'll check out the paper, seems cool!
Logarithms were introduced to reduce multiplication to addition. The exp-log pair allows them to be expressed in terms of one another:
x × y = e^ln\ x\ +\ ln\ y^, x + y = ln(e^x^ × e^y^).
Not a complete answer, since they rely on the same basic arithmetic operators in question, but still neat.
Edit to add: Apparently this is multiplication…

Yep, the ln/exp immediately made me think about the multiplication/addition thing. I could also get 0 easily: eml(1, eml(eml(1, 1), 1)) (basically e - ln(e^e)), and it's trivial to just get the exponential: exp(x) = eml(x, 1)
What I didn't think about is that we could do some tricks with infinities :)
- negative infinity
-∞ = eml(1, 0) - allows us to get the negative logarithm:
neg_ln(x) = eml(-∞, x) - from which it's easy to get negation
neg(x) = neg_ln(exp(x)) - regular logarithm
ln(x) = neg(neg_ln(x)) - then trivial subtraction
x - y = eml(ln(x), exp(y)) - and finally addition
x + y = x - neg(y)
That's so cool!
Edit to add: Apparently this is multiplication…
Yep, multiplication is easy when you have the above, it's basically
x × y = exp(ln(x) + ln(y))
~~As far as I can tell just following through with substitutions leads to exactly the same expression as the one in the image~~
Actually their expression is different, I'm not sure exactly how they got to it...
i believe eml(1,0) is positive infinity.
Oh, you are correct!
In that case we just need one more step of -∞ = eml(1, ∞). Let me fix the original comment