The success of the recent movie “The King’s Speech” has brought public awareness to what the British call stammering and Americans call stuttering. In the movie stuttering is a speech disorder in need of therapy, but stammering is actually part of a whole range of non-pathological phenomena now called disfluencies, including all sorts of interruptions of speech flow. These are typically inserted vocables like “you know,” “I mean,” and various combinations of vowels and consonants (“eh,” ”uh,” “uhm,” etc.), not to mention the currently near-ubiquitous (in North American English, at least) filler “like,” to be heard emanating from the mouths of female speakers below a certain age (45?) in particular.
This last-mentioned word is sometimes dignified by being labeled a “discourse marker” with an approximative or quotative function (among others). A more encompassing characterization would accurately ascribe its pervasive use to a discourse strategy resting on a cultural set toward the message by speakers who use it, viz. that no content is in need of direct ASSERTION: in fact every message, in this strategy, needs to be hedged. The word like is a compact means of implementing such a cultural set because it immediately weakens the assertory value of anything to which it pertains in the utterance.
Nothing could be a surer symptom of a shift in cultural values than the ubiquitous insertion of a word that immediately undercuts the directness of what is being stated. In the last analysis, it is a sign (an index, to be precise) of the speaker’s inability to be responsible for the VALIDITY of ANYTHING that can be asserted.