This article deals with the social-philosophical meaning of degeneration. For other meanings associated with degeneration, please see degeneracy.

The idea of degeneration had a huge influence on science, art and politics from the 1850s to the 1950s. The social theory developed consequently from Charles Darwins Theory of Evolution. Evolution meant that human being development was no longer fixed and certain, but could change and evolve or degenerate into an unknown future, possibly a bleak future that clashes with the analogy between evolution and civilisation as a progressive positive direction. As a consequence theorist assumed the human species might be overtaken by a more adaptable species or circumstances might change and suit a more adapted species. Degeneration theory presented a pessamistic outlook for the future of western civilisation as it believed the progress of the 19th century had begun to work against itself. In 1890 those most concerned by degeneration were progressives unlike the conservatives defenders of the status quo.

Georges-Louis Leclerc, Comte de Buffon (1707-1788) was the first to define "degeneration" as a theory of nature. Buffon incorrectly argued that entire species "degenerated," becoming sterile, weaker, or smaller due to a harsh climates. By 1890 there was a growing fear of degeneration sweeping across Europe creating disorders that led to poverty, crime, alcoholism, moral perversion and political violence. Degeneration raised the possibility that Europe may be creating a class of degenerate people who may attack the social norms, this led to the solution of a strong state to police degenerates out of existence with the assistance of scientific identification.