Asked ''Who ate the cake?'', many people might answer ''Me and him.'', and look upon ''He and I.'' as pretentious.
These same people, however, would ridicule you for saying ''Me ate the cake.''.
Thus we have some evidence of a ''folk grammar'', if you will, with no small intolerance of infractions.
My question is, to what extent are such grammars similar across languages, geographical regions, and historical times? Has anyone ever described systematics in them? Has anyone ever theorized about their origin?
I'm going to leave the forest of your actual query largely to my colleagues, but focus on the particular tree you examine and the notion of "folk grammar".
Note that with the data you have given, your use of the term "grammar" is clearly justified. Since in this dialect -- I'll label it as CR1, some forms are clearly rejected by native speakers, we must infer, correctly of course, that they do have a grammar.
Soo, we find sentences like
1. ''Who ate the cake?'' ''Me and him.'' or "Me". but
2. *Me ate the cake. is ungrammatical and people say
2'. I ate the cake. as they do in Standard English (SE).
What is the difference in the grammar of SE v. CR1? In literary and superstandard spoken SE, conjunction is not relevant to case assignment. Pronouns are assigned nominative or objective case strictly on whether they are the subject of a verb or the direct object, indirect object, or object of a preposition. In a less formal SE, the answer to "Who ate the cake?" is apt to be "me" or "him", and predicate nominative position also gets objective case.
But in CR1, any conjoined pronoun is going to be in the objective case. Me and her went shopping. but I / She went shopping. and the like.
Now, what we have here are two different English dialects, one in which conjunction is completely irrelevant to case assignment and the other in which conjunction is quite relevant. That's all. The only basis for characterizing one as "folk" and the other as "nonfolk??" is that English speaking societies usually associate with SE form with upper class, education, formal situations while the CR1 dialect is associated with informallity, less education, lower class, and -- regional location -- the CR1 dialect is heavily characteristic of the Southern Highlands and the MidSouth generally.
Now, let's look at another language in which conjunction is relevant to case assignment -- Modern spoken and literary French.
French has a series of personal pronouns closely association with verbs: the nominative forms are je 'I', tu 'you sg' il ' he', and so on -- these are subjects of sentences in phonological attachment to the verb. The forms me, te, le, .... are direct objects in close attachment to the verb, The forms moi, toi, lui...
are called "disjunctive" pronouns and these are used as
a. citation forms,
Qui a ecrit c,a? Who wrote that? Moi. 'Me'.
b. objects of prepositions
avec moi, 'with me', pour toi 'for you' avec lui 'with him'
c. when conjoined with another pronoun or a noun,
Marie et toi 'Mary and you', Lui et moi 'him and me'.
NEVER NEVER EVER **** je et il, tu et me... &c.
Soo now -- Standard French is like the English dialect I have labelled CR-1 Conjunction Relevant-1. That is the dialect whose grammar you have called a "folk grammar". But in French it is standard literary French. So, as you see, the "folkiness" is not a function of the actual difference in the rules of the grammar
but is rather a function of social class and which class speaks which grammar.
Oh BTW, the label CR1 implies there may be at least a CR2. There is. It is the English overcorrected dialect in which people use the nominative case for conjoined pronouns instead of the objective case:
She went with he and I.
How came this about? By teachers asking the wrong question because they couldnt imagine a language in which conjunction might be relevant for case assignment:
--Now, Johnnie, you wouldnt say "Him went" or "me went" would you?
--So why would you say "Him and me went?"
This is a rhetorical question so far as Miss Schluckheimer is concerned -- she assumes there is no rational answer to it. Johnny thinks he is stupid but since nobody explains to him that the difficulty is that in SE conjunction is simply disregarded in case assignment, he assumes that what's wrong is that in SE, it is nominative case that is supposed to be used with conjunctions and not objective case. So he overcorrects. And Johnny and teacher are both victims of the assumption that nonstandard dialects dont have grammars.
You are to be commended for not having made that assumption and seen the grammatical pattern in the examples you gave. But as you now also see, what is one language's "folk", i.e. nonstandard grammatical system may well be another people's standard literary language.
Which means that the answer to the first question in your last paragraph is, no, not necessarily.
U of Cincinnati
Dept of Anthropology