The problem I was addressing via this metaphor isn't new in oral tradition studies. Albert Lord, in his seminal 1960 work, The Singer of Tales, entitled his fifth chapter, "Songs and the Song" (99–123). According to this distinction, the plural "songs" refers to any specific performance of the tradition (or parole), and the definite singular "the song" refers to the tradition itself, the langue that precedes and envelops "songs" but is itself unsingable, unutterable, only ever potential. Lord refers to "the song" as "a flexible plan of themes, some of which are essential and some of which are not" (99). And, consequentially, the transmission and preservation of "the song" in these terms differs dramatically from from the transmission and preservation of any given parole. Lord says of the singer of "the song":
His idea of stability, to which he is deeply devoted, does not include the wording, which to him has never been fixed, nor the unessential parts of the story. He builds his performance, or song in our sense [i.e., parole], on the stable skeleton of narrative, which is the song in his sense [i.e., langue]. (99)
If all of this seems a bit confusing, think about any of the seemingly endless versions of any classic Christmas song we've been listening to for the last five weeks. I heard at least three different versions of "Santa Baby" this month, one each by Eartha Kitt, Madonna, and Taylor Swift. These songs are all very different in terms of their style and their affect, and they each evoke a different response from me (e.g., I viscerally hate Madonna's version). Their words may be exactly the same across all three versions (though I haven't checked whether or not they are), but the variation between them is important. So what makes them the same song? And what enables their variations without any of these versions becoming "a different song"? These are the questions I'd like to see us raise, mutatis mutandis, of the four gospels.
In order to raise a similar issue, John Miles Foley refers to the "tale within a tale" in his 1995 book, The Singer of Tales in Performance, which in its very title evokes Lord's earlier work:
[W]e could observe that any performance/version is fundamentally a "tale within a tale," with the avenues of implication necessarily running both ways. The present tale [parole] both enriches and is enriched by the larger, implied tale [langue]—itself unperformed (and unperformable) but metonymically present to the performer and audience" (48, n. 44)
In fact, I first read Foley's book in the summer of 2005, so my landing on the langue/parole metaphor to express these issues was in direct response to Foley's discussion.
All of this comes back to my mind because I'm reviewing The Interface of Orality and Writing: Speaking, Seeing, Writing in the Shaping of New Genres (A. Weissenrieder and R. Coote, eds.; WUNT 260; Tübingen: Mohr Siebeck, 2010). Today I started John Miles Foley's essay, "Plentitude and Diversity: Interactions between Orality and Writing" (103–18). In the overview to his article, Foley refers to "rule-governed variation" and the navigation of "webs of potentials" (103), both of which get at precisely the issue of how any "oral-derived text" relates to the living tradition it expresses. These phrases, I think, provide a more helpful way for thinking about how the gospels, for example, relate to each other and to the larger "Jesus tradition" of which they are but individual instances or expresses (paroles). Indeed, the phrase "rule-govered variation" nearly depends on the langue/parole metaphor for its explanatory power: the set of rules that governs variation in the expression of any tradition is the system of potentials (langue) that enables the expression (parole) in the first place.