Question. Why does the word "any" in negative sentences changes its meaning from "for all" to "there exists"?
Origin of the question. I have a question about translating English to predicate logic. I don't understand well enough how the word "any" should be translated in predicate logic in general. I know that this word has principal meaning "for all", but I have found one example where it, in my opinion, means "there is at least one".
None of Occam's followers likes any realists. This example is from Suppss's "introduction to logic"
(x)(Ox->(y)(Ry->Lxy))
In my opinion this is equivalent to: "There is not at least one follower of Occam who likes at least one realist".
My attempt to solve this issue. So let us consider simpler example. Say, the sentence: No dogs likes any cat. (x)(Dx->(y)(Cy->Lxy)) In my opinion it is equivalent to: "There is no single dog who likes at least one cat" and not equivalent to: "There is no single dog who likes all the cats".
First one. There is a set of all the dogs. There is a set of things that like at least one of the cats. So intersection of these sets is empty.
Second one. There is a set of all the dogs. There is a set of all the things that like all of the cats (even mad and ill ones). So intersection of these sets is empty.
From second one we can infer that there might be a dog who likes some cats, but not all of them (It might like only fluffy ones). From first one it follows that there can't be any cat that is liked by any dog.
So I concluded that "any" changes it's meaning from "for all" to "there exists" in some sentences, possibly in all negative sentences.
My research. There is a similar question: Reference request for the logical analysis of the word "any" In my opinion it doesn't fully answer the question, they say that it is some artifact of English language. So there is grammar book, that tells that in these cases we use "any" as existential and in other cases as universal quantifier.
I think that it deeper phenomenon than just some grammatical artifact of English. I know that there is similar issue with translation of "any" in other different languages. So in these languages there is the same issue.
P.S.: I have read 6 books in logic, I know what a square of opposition is. I am a chemist who has logic as a hobby.