I don't know if I've wrote about it here on this blog (some time ago) or perhaps it was in my old email distribution list where I talked about my suspicions that there might be more than one form of nouns, as in that syllogistic argument:
all men are mortal;
Socrates is a man;
therefore, Socrates is mortal.
All things being equal one would assume that a purely nominal construct like "(the) man is Socrates" would have the same kind of value as "Socrates is (a) man" - but they don't, at least not in the English Subject Verb Object structure. And, I kind have doubts that it may have to do with the definite and indefinite articles "a" and "the" (though these are good clues). There seems to be an unmarked (and unspecified) grammatical mood/case/tense lurking there somewhere because - leaving aside the abstract and technical considerations for the moment - both are declarative phrases in effect specifying that Socrates is a man (or, that the man is (indeed) Socrates) which amount to pretty much the same thing - a plain declarative.
We may try and explain that perhaps it has something to do with "subject" and "object" grammatical functions (both are nouns after all), but interchanging "Socrates" for "man" and vice versa doesn't change the fact that we're talking about the same thing because both phrases are intransitive constructs (ie, complete in and of themselves and do not require an adjunct phrase to complete their grammaticalities) and we're actually not talking about two things but one (Socrates = man).
The only way to distinguish the differences is to construct a convoluted and contrived argument like, "the man is Socrates (because Socrates is a man), and it is he that we're talking about". The problem actually has to do with "passive" and "active" tense, as in "the man is Socrates...and it is he we're talking about" - which is inherently a "passive" construct in direct contrast to "Socrates is a man" - which is clearly in the active tense.
In Inuktut the two would be:
"(taanna) angut Socrates-ngujuq" = lit. "(this) man, Socrates is he (called)" = "(the) man is Socrates"
"Socrates angutiujuq" = "Socrates is a man"
which also suggest that the differences have to do with "passive" and "active" tenses.
There are other similiar subtle problems of linguistics - as in "that that" and "had had" constructs - that also point to tense (in this case "perfectivity" rather than "passive vs active") as the determining factor of differentiation.
I know that verbal and nominal forms are stumbling blocks for many interpreter/translators here in the Inuit world, but the problem of tense is something many times more subtle than these questions of verb and noun constructs - that is, "snacks" translated as "tamulugaksaliuqtut" (they are making snacks) rather than "tamulugaksat".
When we, here in Nunavut, first started talking about Inuit Qaujimajatuqangit (that which is long known by Inuit = Inuit traditional knowledge = IQ) I had a hard time trying to explain the difference between "active" and "passive" constructs in proposing that we call IQ Inuit Qaujimaningit (purely, Inuit Knowledge) rather than the one that was first coined as IQ.
I have heard many an Inuit elder asking (in whispering tones) "what is 'it' that is long-known?" because there is an expectation caused by passive tense that what "it" is will be specified (the "that which" is long-known); whereas, the "Inuit Qaujimaningit" appeals to the body of knowledge as a concept rather than a hanging passive construct implied by "Inuit Qaujimajatuqangit...(are theses...)". Compare the ja construct of IQ with "(the) man is Socrates" and you'll see that without "Socrates" the phrase would be incomplete.
As a terminologist I'm asked to review translations, and often the problem is not perceived to be a "problem" by people who are otherwise very competent speakers of Inuktitut (many of them are better speakers of Inuktitut than I am) but who happen to think that word-level translation (ie, literal translations rather than meaning-based translations) is a good form (sort of like speaking English with a French grammar sort of makes English somehow sound nobler or more poetic when plain-speech has a better impact when it's not contrived thus).
My nuliakuluk and I had an on-going discussion about a line in a song that went "I kiss your heart while you sleep" which she said that, in French, the poetics is completely allowed. I suppose it is also completely acceptable in English (at least, I can't make a convincing argument that it isn't). But there is something that doesn't quite sound "right" about the line...