Degeneration theory is, at its heart, a way of thinking, and something that is taught, not innate. A major influence on the theory was Emil Kraepelin, lining up degeneration theory with his psychiatry practice. The central idea of this concept was that in “degenerative” illness, there is a steady decline in mental functioning and social adaptation from one generation to the other. For example, there might be an intergenerational development from nervous character to major depressive disorder, to overt psychotic illness and, finally, to severe and chronic cognitive impairment, something akin to dementia. This theory was advanced decades before the rediscovery of Mendelian genetics and their application to medicine in general and to psychiatry in particular. Kraepelin and his colleagues mostly derived from degeneration theory broadly. He rarely made a specific references to the theory of degeneration, and his attitude towards degeneration theory was not straightforward. Positive, but more ambivalent. The concept of disease, especially chronic mental disease fit very well into this framework insofar these phenomena were regarded as signs of an evolution in the wrong direction, as a degenerative process which diverts from the usual path of nature.
However, he remained skeptical of over-simplistic versions of this concept: While commenting approvingly on the basic ideas of Cesare Lombroso’s “criminal anthropology,” he did not accept the popular idea of overt “stigmata degenerations”, by which individual persons could be identified as being “degenerated” simply by their physical appearance. While Kraepelin and his colleagues may not have focused on this, it did not stop others from advancing the converse idea.
An early application of this theory was the Mental Deficiency Act Winston Churchill helped pass in 1913. This entailed placing those deemed “idiots” into separate colonies, or anyone who showed sign of a “degeneration”. While this did apply to those with mental disorders of a psychiatric nature, the execution was not always in the same vein, as some of the language was used to the those “morally weak”, or deemed “idiots”. The belief in the existence of degeneration helped foster a sense that a sense of negative energy was inexplicable and was there to find sources of “rot” in society. This forwarded the notion the idea that society was structured in a way that produced regression, an outcome of the “darker side of progress”.
Those who had developed the label of “degenerate” as a means of qualifying difference in a negative manner could use the idea that this “darker side of progress” was inevitable by having the idea society could “rot”. Considerations to the pervasiveness an allegedly superior condition were, during the nineteenth century, frighteningly reinforced the language and habits of destructive thinking.