Bahktin argues that language is heteroglot and in fact "cohabit with one another" (291). There exist boundaries in every circumstance which give birth to new languages and new conventions. Bahktin even states that the specificity of family jargon can be considered a new language of its own. Shakespeare's language is unique because it is considered not only an art form, but a source of cultural and political discourse. This creates in much of his script a double voiced nature which expresses the intent of the character as well as the playwright's authorial intentions. Where Bahktin describes Heteroglossia as expressing these authorial intentions in a "refracted way", Shakespeare's "refraction" is through whatever character and theme he has chosen to concentrate his play on.
In his passage on heteroglossia, Bahktin describes double-voiced discourse as two voices, two meanings, and two expressions. Our most recent play, Othello, is a tragic play about a black general falling in love with a Venetian nobleman's daughter, and facing the challenges of race and fate. Using an example from the script of Othello, he says (while he is alone),
"O curse of marriage, that we can call these delicate creatures ours, and not their appetites! Yet 'tis the plague of great ones; Perogatived are they less than the base. 'Tis destiny unshunnable, like death. Even then this forked plauge is fated to us when we do quicken." (272-277)
When reading this passage in context of the play, Othello is battered with frustration because he believes his newlywed wife is having an affair against him. His "destiny unshunnable" is his inability to escape the social expectations of marriage and the emotional pressure it puts upon those who marry one another. If, on the other hand you step back and think as to why Shakespeare had him say this specific line, you can read into the commentary on Othello's unshunnable destiny of being black. Although Shakespeare is white, middle class, and a playwright, he's utilizing the voice of a black general to comment on race and politics. At the end of the play, you're left wondering whether this tragedy would have happened if Othello had not been a black role. Shakespeare wrote these plays being fully aware that audiences would perceive and digest this material as they were seeing it on stage He used the notion of double voicing as a method to express cultural beliefs and engender some understanding of the power of the script. In this you can see how the refraction of discourse of character and narrator is yet another tool an author may use to manifest his intentions.