The prospect of what Wells called “downward modification” would haunt the European imagination in the last decades of the nineteenth century. Every direction one turned, scientists pointed toward the possibility, even inevitability, of changes within the physical or social environment that would irrevocably reshape the human form and human culture. As nineteenth-century physics, evolutionism, and social medicine generated the highly compatible models of entropy, species “reversion,” and human pathology, it became clear that such alterations would be disastrous ones, transforming the human species into something unrecognizable, perhaps even ensuring its extinction. The conflation of these models is best exemplified in degeneration theory, discussed below, prominent throughout Europe at the fin de siècle.

Degenerationism is a highly narrative discourse, concerned, as Daniel Pick writes, with “the dynamic patterns which underpinned a chain of changing pathologies across generations.” Like that of entropy, degenerationism's is a minus narrative, reversing the direction of ameliorist versions of evolutionism, which proposed natural history as an inevitable progression towards “higher” and more complex forms, and human history as an inevitable progression towards a higher and more rarefied state of civilization. The telos of the narrative in the first case was the human form; in the second, European culture. Degeneration theory, however, not only reversed the narrative of progress, proposing a negative telos of abhumanness and cultural disarray. It also accelerated the pace of the narrative, emphasizing the mutability and flux of human bodies and societies. Degenerationism, in other words, is a “gothic” discourse, and as such is a crucial imaginative and narrative source for the fin-de-siècle Gothic.