A group of key essays written by Zola between the late 1860s and the early 1880s—the preface to Thérèse Raquin, for example, along with the pieces collected as The Experimental Novel —provides a first foundation for core conceptions of politicized literature that together form an aesthetic of clarity. Close readings of Zola's initial attempts to articulate his political aesthetics, and of metafictional or metatheatrical moments in fiction and drama by him and others, reveal the priority of representational clarity and certainty, content that can be clearly represented, and an epistemology derived from scientific paradigms like those which were being popularized through the work of Charles Darwin and Karl Marx.