Because you can patent a machine. The argument is that software is "just math" (because it literally is just doing binary arithmetic) and mathematics cannot be patented.
Math should be patentable, too. I see no reason for why not.
The old argument that it's discovered rather than invented is bullshit. Multiple people can always have the same idea for an invention because we think alike and live in the same environment.
Or just ban patents altogether. Of course, this may discourage companies from investing in R&D and that's the real problem: how expensive is it to invent something, and does it justify a 20-year monopoly? But there are no good answers here, and trying to draw a line between math and non-math is bollocks.
There’s just something obscene about patenting mathematics. The universe gifts us these truths and our first instinct is that it should be the property of a human.
Patents exist to incentivize invention. As long as mathematicians are content to do mathematics for the love of it, and they certainly are, there’s no need for mathematical patents.
Practically speaking, mathematical ideas are building blocks not products. Patents on mathematical ideas discourage invention rather than encouraging it because they prevent use of that idea in new products - an idea that would have been discovered anyway. For example the parents of elliptic curve cryptography and arithmetic coding were hugely damaging to invention overall. Patenting a new kind of cork screw doesn’t have this problem, it’s a destination, not an intermediate.
Math can be viewed as a product of how our minds work. We use abstractions to understand and predict the universe, but it's always imperfect, and the theories always incomplete.
E g., you'd think 1+1=2 is some universal truth, except integers don't exist in nature, being just another abstraction that we came up with. And of course, people can rediscover integers repeatedly, but that just says more about how our mind works.
And yes, math is a building block, but so is software. If math theories aren't patentable, that should happen based on them being trivial or perhaps being too useful to society, and not due to some romantic notions of discovery and the universe. Software, too.
But a machine can also be mathematically described. Should that render it unpatentable, or will that have to wait until the grand unified theory of everything is sorted out?
Why does that only hold when the result in question is in software? Machines are just tools for achieving results.