Chance Causal Setting
In fictional universes governed by chance, the logical sequence of the narrative events is interrupted, often suddenly, by statistically improbable occurrences. Unlikely encounters, extraordianry coincidences, convenient accidents, and other surprising narrative turns may at any moment be introduced into the text. In employing a chance causal setting, an author often renders clearer his or her own presence in the narrative as the creator of a turn of events that is unlikely to occur in the real world.
The fictional universe of Henry Fielding's Joseph Andrews is, for example, one governed largely by chance. Near the end of the novel, as the eponymous hero and his beloved Fanny approach marriage, they meet a pedlar who claims that Fanny was, as a very young child, kidnapped from her family and brought to the home of Sir Thomas Booby, where she later met her betrothed. The pedlar then goes on to reveal a shocking coincidence: the family from whom Fanny was kidnapped is none other than that of Joseph. This revelation, indicating that they are brother and sister, of course intrudes upon Fanny and Joseph's plans to marry. Soon, however, a second surprising revelation rectifies matters, as Mrs. Andrews reveals that the Gypsies who stole Fanny from her crib effectively replaced her with the young Joseph. The narrative reverses, then, the improbable notion of Fanny and Joseph's blood relation with an equally dubious changeling plot (284-297).