Perhaps the most obvious theory that hypertext embodies and makes explicit is Julia Kristeva's (1986) notions of intertextuality: Kristeva, influenced by the work of Bakhtin, charts a three-dimensional textual space whose three "coordinates of dialogue" are the writing subject, the addressee (or ideal reader), and exterior texts; she describes this textual space as intersecting planes which have horizontal and vertical axes:
The word's status is thus defined horizontally (the word in the text belongs to both writing subject and addressee) as well as vertically (the word in the text is oriented towards an anterior or synchronic literary corpus) . . . each word (text) is an intersection of words (texts) where at least one other word (text) can be read . . . any text is constructed as a mosaic of quotations; any text is the absorption and transformation of another. (p. 37)
Essentially, every text is informed by other texts which the reader has read, and the reader's own cultural context. The simplest articulation of intertextuality can be seen in the footnotes that indicate source materials to which a given text is alluding, or which are known to have influenced the author. A constructive hypertext can make this notion of intertextuality an externally accessible "mosaic" of multiple texts, placing the internal connections about which Kristeva theorizes into a visible forum which can be expanded by each subsequent reader.