“Knowledge-hiding children” and the history of autism in Denmark: the origins and influence of a key concept, ca. 1963–1990

This article traces the history of special educational approaches to autism in Denmark, focusing on the notion of “hidden knowledge” (skjult viden) and the associated hand guidance and skill-testing practices that took shape at Sofieskolen in the 1960s. Founded in 1964, Sofieskolen was among the first special schools in the world for children then classified as “psychotic” or “borderline psychotic”. While the idea that such children might possess unrecognised abilities was not unique, it developed a distinctive form and influence in Denmark. The article analyses the social, political, and conceptual dynamics that supported the emergence and uptake of the hidden knowledge framework. It begins by examining the background of the school’s establishment and founder Else Hansen’s understanding of child psychosis as a condition characterised by an anxiety-driven “blocking” of expressive functions. Hansen’s ideas are then situated in relation to international developments in special education and autism research, with particular attention to debates over testability and the relationship between autism and intellectual disability. The concluding sections address the decline of the hidden knowledge concept in the 1980s and the specific features of the Danish field during the period.