OK, yes, you can break any grammatical rule if you invent new rules to replace it; you can also modify a C compiler to accept some Lispy constructs. My point is, style is fashion, but grammar is something deeper.
Except that you don't really need any formalized grammar for communication and language to occur. Do you know the grammar of your native language well? I don't really known mine, and I'm certain I don't have to know it to use the language. Ditto for all the people I know. Grammar is a nice afterthought, but it's not a primary part of a language. It's just a snapshot of ever-evolving fuzziness that is language.
> Grammar is a nice afterthought, but it's not a primary part of a language.
This is wrong, and it points up a fundamental problem with how we teach language. Grammar is language; it defines language. You know it at a deep level that is practically instinct for you; you don't know it in the same way you know how to type, but you still know it. If you didn't, you couldn't use language.
Two different kinds of learning are both equally vital to how humans get along: By osmosis and by explicit instruction. Your mother tongue is learned via osmosis, tying your shoe is learned through explicit instruction. Both are vital methods, but only the second (explicit instruction) leaves you able to fully verbalize what you know in a cogent manner.
The rules of grammar that we "learn" are an attempt to model a process that we don't understand very well. It's hard to say that grammar defines a language when a speaker/writer can at will break any rule and enhance their communication by creating new constructions and vocabulary on the fly. Rules are at best a simple description of some expectations. Context, observation, and additional communication can completely override any rule.
Grammers are useful in communication, but they certainly don't define and constrain it; they are like standardization in tool making and manufacturing. But words combined together, in a context, can behave in ways that no grammar can describe.
In fact I'd say that grammars are more conscriptive than they are descriptive. Literacy and education teach us to speak and write in grammars for formal, ritual use. But when we need to get work done or communicate important ideas, anything goes...
Yet somehow if me says grammatically not correct sentence understand you me quite well. Language evolves by people constantly bending, breaking and rethinking rules of grammar. And language evolves constantly, it's not a static thing. Even contemporary English is very different from what was used 300 years ago.
Maybe we have different understanding of the word "to know"? I "know" my language by having something I could describe by a mental bayesian probability model of the fuzzy structure that is "the language people use". Without any explicit grammar inside. I use both Polish (native) and English via "sounds OK to me = it's correct" heuristic, trained mostly on talking, reading and listening, and to the lesser extent on grammar exercises.
