The beast in man: degenerationism and mental retardation, 1900-1920.

It is widely believed that the eugenics movements was largely responsible for the turn of the century perception that individuals with mental retardation were a social menace. However, that explanation fails to account for the vast corpus of 19th century degeneration theory, which, in the Progressive era, became the lens through which mental retardation was viewed. In this paper I have described the chain of theological and scientific reasoning that led to the linkage of mental retardation with the evolutionary "mark of the beast," a development that not only helped fuel the notorious myth of the "menace of the feeble-minded" but also cast a long shadow into this century.