Introduction: idiocy, culture and human relations -- 'Stripping our own hearts naked': William Wordsworth and John Wilson read 'The idiot boy' -- A 'pupil of innocent nature!' The wild boy of Aveyron goes to Paris -- Diminished men: masculinity and idiocy -- Essential women: feminity and idiocy -- Holy fools, witty fools, depraved fools: folly, innocence and sin -- History, society, economy: holy fools and idiots come home in nineteenth-century literature -- Barnaby Rudge, idiocy and paternalism: assisting the 'poor idiot' -- Innocence, philanthropy and economics: the new 'asylum' idiot -- Sensational idiocy -- 'The sins of the fathers': idiocy, evolution and degeneration -- Danger and degeneracy: the threat of the urban idiot -- The problem of the feeble-minded: the Royal Commission, eugenics and eternal chaos -- Epilogue.