How does Mikhail Bakhtin's idea of 'polyphonic' differ and or relate to Julia Kristeva's concept of 'intertextuality'?
Kristeva was influenced by Bakhtin's ideas in her own definition of intertextuality. Kristeva's starting point was Bakhtin's concept of heteroglossia, defined in one of the Enotes pages on Bahktin's The Dialogic Imagination, as "the dialogue of languages as it exists in a given era":
In any given work or utterance it is possible to distinguish words which belong to, or derive from, the work or utterance of another, or, more accurately, several, or even many, others.
A text is thus defined as a "polyphonic" construction where multiple meanings and points of view coexisted and struggled for preminence. Kristeva used this insight to elaborate her notion of "intertextuality", the process through which we define the meaning of a text in relation to other texts. The ultimate meaning of a text for a reader, Kristeva argued in Desire in Language, is not directly passed on from the author, but is negotiated by the reader who puts it in conversation with other texts.