the biology of parasitism were hugely influential; the poor physical condition of many British Army recruits for the Second Boer War (1899–1902) led to alarm in government circles. Psychiatrist Henry Maudsley initially argued that degenerate family lines would die out with little social consequence, but later became more pessimistic about the effects of degeneration on the general population; Maudsley also warned against the use of the term "degeneration" in a vague and indiscriminate way. Anxieties in Britain about the perils of degeneration found legislative expression in the Mental Deficiency Act 1913 which gained strong support from Winston Churchill, then a senior member of the Liberal government. In the fin-de-siècle period, Max Nordau scored an unexpected success with his bestselling Degeneration (1892). Sigmund Freud met Nordau in 1885 while he was studying in Paris and was notably unimpressed by him and hostile to the degeneration concept. Degeneration fell from popular and fashionable favor around the time of the First World War, although some of its preoccupations persisted in the writings of the eugenicists and social Darwinists (for example, R. Austin Freeman; Anthony Ludovici; Rolf Gardiner; and see also Dennis Wheatley's Letter to posterity). Oswald Spengler's The Decline of the West (1919) captured something of the degenerationist spirit in the aftermath of the war. Psychology and Emil Kraepelin 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