[FOM] expressive power of natural languages

[Richard Heck]

On 11/30/2011 06:59 PM, Monroe Eskew wrote:
> It seems to me that English cannot be classified as any type of formal language.
>
> First, how would many-sorted first order logic be enough to capture things like tenses, subjunctive moods, commands and exclamations, gerunds, prepositions, adverbs, reference to English itself, etc. in a way that at all resembles the actual structure of spoken English?
>
Semanticists are working on these very problems, and have been doing so
for quite a long time.

> Second, the rules of English grammar are somewhat fluid and the language changes over time.  Without well-defined syntax, how could it be formal?
>
Linguists generally don't care about "languages" in this sense---what
Chomsky called "E-languages"---but instead in "I-languages", which is
(roughly) the language spoken by an individual at a time, intensionally
conceived.

> Third, unique readability fails.  Bob said Joe saw his friend.
>
This is one of the reasons linguists don't care about E-languages.

> Fourth it is often vague.
>
Vagueness too is the subject of much research.

> Fifth, what rules of grammar or semantics prevent the Berry paradox in English?  Nothing; the paradox makes us realize that the intuitive semantics don't work.
>
Why think anything needs to prevent the Berry paradox? or the liar? or
any other such paradox? I don't see what this has to do with the
question asked.

Richard