Genre Theory

The utterance, which is defined by the changes in speaker (or writer) at either end, and dependent for meaning on the previous utterances uttered or received by the utterer and those of the audience, is the smallest meaningful unit of language. There—done.
To a practicing rhetorician (or technical communicator) this is obvious, and an example of the importance of addressivity. In a field less concerned with the actions of the receivers of the utterance—such as linguistics, where the actions beyond the conversation are secondary to the structure of the utterances themselves—smaller units of meaning are essential. The sentence (which Bakhtin decries as being arbitrarily defined) depend on the word for meaning, and it seems the smallest for its constituents, letters, have no meaning other the sound they represent. Even then, Bakhtin’s argument could be applied by arguing for the syllable, which frequently carries meaning from the etymological roots—similar to the influence of previous utterances described by Bakhtin.
However, Bakhtin reverses the direction of meaning mandated by common sense (and as Mark Twain said, common sense is the most abundant resource in the world, for when asked if one has common sense, everyone will say “yes�). Meaning, we learn as children, comes from within the unit of speech. The meaning of words depends on the phonics that they comprise, and the meaning of a sentence depends on that of its constituent words.
Other theorists of language look inward. For example, Burke considers the tropes and contrasts the semantic and poetic meanings of words—the latter of which parallel’s Bakhtin, though still centers on the word. Aristotle, and centuries later, Perelman, thoroughly examine the components of arguments, another inward concept. Literary critics place the works in the context of the time, for example the Transcendentalists of the 19th century, but then return to the details, to the words and sentences.
To a modern rhetorician, however, the power of the word lies not in its durability, but in its mutability. Words move from field to field and language to language, continually acquiring new connotations and denotations. At a more basic level, two words might be spelled the same in two different languages, yet have completely unrelated meanings because of their independent evolution. The meaning depends not on the letters within them, but on the utterances that they themselves are within.
The utterances, here accepting Bakhtin’s definition as the content within the utterer’s turn, themselves still lack meaning. A post-structuralist (or would it be structuralist) argument might extend the meaninglessness of a word to imply the meaninglessness of a chain of words, and it would agree with Bakhtin. The meaning of the utterance cannot be understood without reference to those surrounding it.
As we move outward, especially in technical communication, we find the manuals serving purposes in organizations, and as such, need to meet the needs of those organizations. When I described the origin of the memo metaphor seen in emails, my students accepted it as obvious why you’d want to know the date, sender, recipient, and subject, and were delighted (ok, I’m exaggerating) to learn of its origin with the typewriter and the vertical file. Looking at language from this perspective moves us outward from the text to the reason why it exists. Our lives.