The introduction outlines historical and formal links between Bildung, biology, and the narrative strategies used by modernist novelists. The classical Bildungsroman, with its insistent linearity, originated from the same organicist aesthetics and ideology as one of the nineteenth-century’s most pervasive biological narratives: recapitulation, in which individual development (ontogeny) repeats species evolution (phylogeny) in miniature. By the early twentieth century, however, this linear biological paradigm was giving way to a more complex set of nonlinear developmental models, which served as inspiration or even templates for the formal experiments of several prominent novelists seeking to rehabilitate the ideals associated with the Bildungsroman. Linking the various new models is the concept of reversion, a developmental disruption of simple chronology that would seem, from the perspective of recapitulation theory, to be regressive or otherwise pathological. Each of the novels featured in the book incorporates some form of biologically derived reversion into its narrative structure, allowing it to retain Bildung’s spiritual and aesthetic ideals while challenging the reductionism and sinister political implications of recapitulation theory.