What is a question about this article? If the question is unanswerable, say "unanswerable".

Genre fiction also showed it could question reality in its 20th century forms, in spite of its fixed formulas, through the enquiries of the skeptical detective and the alternative realities of science fiction. The separation of "mainstream" and "genre" forms (including journalism) continued to blur during the period up to our own times. William Burroughs, in his early works, and Hunter S. Thompson expanded documentary reporting into strong subjective statements after the second World War, and post-modern critics have disparaged the idea of objective realism in general.

William Burroughs continued to define the lines between literature and what?
unanswerable