Abstract The following article investigates the unique epistemic changes in conceptions and representations of chance and causality that begin with the poetry and thought of Samuel Taylor Coleridge and William Wordsworth (and first‐generation British Romanticism) and that are elaborated and expressed ultimately in Charles Darwin's theories of organic variation and evolution through natural selection. I argue that both Coleridge's The Rime of the Ancyent Marinere (1798) and Wordsworth's The Prelude (1805) rely on a shift from describing chance as an ontological concern to chance as a discursive matter. Drawing on Darwin's statistical projects from the 1850s and selections from his correspondence in which he begins to articulate his developmental theory of organic variability, I then reveal that Darwin too makes a similar intellectual leap from characterizing chance as event to theorizing chance as idea. As I propose, chance – as an epistemological or discursive matter – radically reconfigures both literary and scientific representations of causality produced during this period. The essay thus concludes by suggesting that the idea of chance infiltrates Romantic and Victorian depictions of the natural world so thoroughly that these representations are impossible without a reorganization of the clauses and stipulations of causality.