Understanding Insanity: Pellagrous Insanity in Italy and General Paralysis of the Insane in the United Kingdom

Abstract

AbstractIn this chapter we examine the contemporary medical understanding of pellagrous insanity, and the conceptual and diagnostic challenges this posed. We do this by comparing debates surrounding pellagrous insanity in Italy with those waged around the same time in the United Kingdom vis-à-vis general paralysis of the insane (GPI). The latter disease was eventually linked to syphilis, even if the exact relationship between syphilis and insanity remained ambiguous—much like the body-mind link in pellagra and pellagrous insanity. We compare the two illnesses by examining how doctors classified them, sought to identify their causation and pathogenesis, and how this influenced diagnosis and treatment during the second half of the nineteenth century. Although pellagra and general paralysis were acknowledged as specific and distinct clinical entities, they nevertheless both lacked a recognised and precise aetiology and pathogenesis. As a result, the diagnostic process gave room to doubts, uncertainties and questions. Together, they provide us with historical and conceptual evidence of the need to subject ‘diagnostic reason’ to constant criticism.