Well, going by formal language theory, FOL is equivalent to a universal Turing machine, which is probably also the full expressive power of human language. Therefore, everything that can be said in human language should in principle be possible to say in FOL. I don't think this is controversial.
Notice again that I don't think this is feasible in practice. At least not with hand-crafted FOL expressions and certainly not with existing technology.
I'm not sure what "non-leaky abstraction" means. Would formal language theory fit the bill?
Yeah but humans don't have a single consistent logical model for all reasoning - i believe that all my models can be in fol, but i don't believe that they can be unified in fol
Oh, I'm not saying anything about how humans think, or model the world. FOL is a formal language. It can express the same things that natural language can express and you can do reasoning in it (actually- let's say "inference" because reasoning is a bit of a loaded term), but I make no claim that it's how humans really think.
I mean, I don't believe that is true any more that I believe calculus, or linear algebra are the way we think. Those are just formal systems that we can use to get various results about the world- but is that how we really think inside our heads? I kind of doubt it.
I'm just talking about the expressive power of first-order predicate calculus here, not about whether it's a good model for human intelligence.
Notice again that I don't think this is feasible in practice. At least not with hand-crafted FOL expressions and certainly not with existing technology.
I'm not sure what "non-leaky abstraction" means. Would formal language theory fit the bill?