Usually in the realms of literature and the arts each major movement can be seen as a rebellion against whatever came before it, so Romanticism upstages Classicism, only to be done in in turn by Realism as people weary of the excesses of one style only to rush headlong into the excesses of its opposite. But sometimes it happens that one style is replaced by an even more extreme version of itself, as was the case when Realism in literature and the visual arts was replaced in the late 19th- and early 20th-centuries by Naturalism, a movement that was inspired by adaptation of the principles and methods of natural science, especially the Darwinian view of nature. One of the most perfect examples of this movement is Jack London's short story "To Build A Fire", published in The Century Magazine in 1908 with its themes of the fragility of human survival and the ways in which we as humans are defined by the ways in which we are at odds with the rest of nature. (A more "juvenalized" version had been published previously, but it is the 1908 version that is now considered to be the definitive one.) (http://sunside.berkeley.edu).
In literature, Naturalism extended the tradition of realism, aiming at an even more faithful, unselective representation of reality. It is not coincidental that the rise of Naturalism should follow the rise of photography as an artform (and as a technological possibility), for both photography and naturalism (whether in literature or in the visual arts) attempted to give to the audience or reader a sense of looking at unmediated, uncreated life. Jack London does not want us to remember that we are reading a story that he has made up, but rather he wishes to give us the sense that we ourselves are there. His writing is meant to be invisible, presented to us like a documentary photograph without moral judgment.
Naturalism as practiced by London (as well as other writers like Stephen Crane) differed from Realism in its...