'Belief', 'opinion', and 'knowledge': the idiot in law in the the long eighteenth century

From the early eighteenth century the legal characterisation of idiocy became an increasingly significant public issue, as questions of capacity and self-management assumed growing importance in the burgeoning mercantile economy. As well as the idea of the ‘born idiot’, a new concept of imbecility began to form, based on the idea of lifelong ‘weakness of understanding’. Eighteenth-century capacity trials in England reveal an ongoing conflict between libertarian resistance to state intervention in the lives of citizens, however mentally incapacitated they might be, and a belief that the state should be responsible for protecting individuals against exploitation and the corruption of bloodlines. From the late eighteenth century French medico-legal theorists, supported by the ‘scientific’ enlightenment ideals of the French revolution, proposed a medicalised appropriation of legal decision-making over capacity. While these ideas gained some currency among a small group of British medical men working in the field of idiocy, they faced strong public and legal resistance throughout the nineteenth century on the grounds of liberty of the subject. Both legal and medical formulations of idiocy in the eighteenth and nineteenth centuries borrowed heavily from popular, ‘common-sense’ public notions about what constituted an idiot